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drm/nouveau/fb: add gm20b device
[linux/fpc-iii.git] / drivers / gpu / drm / drm_dp_mst_topology.c
blobaa644487749c9cbab104f2ea77c819baf7d6b250
1 /*
2 * Copyright © 2014 Red Hat
3 *
4 * Permission to use, copy, modify, distribute, and sell this software and its
5 * documentation for any purpose is hereby granted without fee, provided that
6 * the above copyright notice appear in all copies and that both that copyright
7 * notice and this permission notice appear in supporting documentation, and
8 * that the name of the copyright holders not be used in advertising or
9 * publicity pertaining to distribution of the software without specific,
10 * written prior permission. The copyright holders make no representations
11 * about the suitability of this software for any purpose. It is provided "as
12 * is" without express or implied warranty.
13 *
14 * THE COPYRIGHT HOLDERS DISCLAIM ALL WARRANTIES WITH REGARD TO THIS SOFTWARE,
15 * INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS, IN NO
16 * EVENT SHALL THE COPYRIGHT HOLDERS BE LIABLE FOR ANY SPECIAL, INDIRECT OR
17 * CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE,
18 * DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER
19 * TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE
20 * OF THIS SOFTWARE.
21 */
22
23 #include <linux/kernel.h>
24 #include <linux/delay.h>
25 #include <linux/init.h>
26 #include <linux/errno.h>
27 #include <linux/sched.h>
28 #include <linux/seq_file.h>
29 #include <linux/i2c.h>
30 #include <drm/drm_dp_mst_helper.h>
31 #include <drm/drmP.h>
32
33 #include <drm/drm_fixed.h>
34
35 /**
36 * DOC: dp mst helper
37 *
38 * These functions contain parts of the DisplayPort 1.2a MultiStream Transport
39 * protocol. The helpers contain a topology manager and bandwidth manager.
40 * The helpers encapsulate the sending and received of sideband msgs.
41 */
42 static bool dump_dp_payload_table(struct drm_dp_mst_topology_mgr *mgr,
43 char *buf);
44 static int test_calc_pbn_mode(void);
45
46 static void drm_dp_put_port(struct drm_dp_mst_port *port);
47
48 static int drm_dp_dpcd_write_payload(struct drm_dp_mst_topology_mgr *mgr,
49 int id,
50 struct drm_dp_payload *payload);
51
52 static int drm_dp_send_dpcd_write(struct drm_dp_mst_topology_mgr *mgr,
53 struct drm_dp_mst_port *port,
54 int offset, int size, u8 *bytes);
55
56 static void drm_dp_send_link_address(struct drm_dp_mst_topology_mgr *mgr,
57 struct drm_dp_mst_branch *mstb);
58 static int drm_dp_send_enum_path_resources(struct drm_dp_mst_topology_mgr *mgr,
59 struct drm_dp_mst_branch *mstb,
60 struct drm_dp_mst_port *port);
61 static bool drm_dp_validate_guid(struct drm_dp_mst_topology_mgr *mgr,
62 u8 *guid);
63
64 static int drm_dp_mst_register_i2c_bus(struct drm_dp_aux *aux);
65 static void drm_dp_mst_unregister_i2c_bus(struct drm_dp_aux *aux);
66 static void drm_dp_mst_kick_tx(struct drm_dp_mst_topology_mgr *mgr);
67 /* sideband msg handling */
68 static u8 drm_dp_msg_header_crc4(const uint8_t *data, size_t num_nibbles)
69 {
70 u8 bitmask = 0x80;
71 u8 bitshift = 7;
72 u8 array_index = 0;
73 int number_of_bits = num_nibbles * 4;
74 u8 remainder = 0;
75
76 while (number_of_bits != 0) {
77 number_of_bits--;
78 remainder <<= 1;
79 remainder |= (data[array_index] & bitmask) >> bitshift;
80 bitmask >>= 1;
81 bitshift--;
82 if (bitmask == 0) {
83 bitmask = 0x80;
84 bitshift = 7;
85 array_index++;
86 }
87 if ((remainder & 0x10) == 0x10)
88 remainder ^= 0x13;
89 }
90
91 number_of_bits = 4;
92 while (number_of_bits != 0) {
93 number_of_bits--;
94 remainder <<= 1;
95 if ((remainder & 0x10) != 0)
96 remainder ^= 0x13;
97 }
98
99 return remainder;
100 }
101
102 static u8 drm_dp_msg_data_crc4(const uint8_t *data, u8 number_of_bytes)
103 {
104 u8 bitmask = 0x80;
105 u8 bitshift = 7;
106 u8 array_index = 0;
107 int number_of_bits = number_of_bytes * 8;
108 u16 remainder = 0;
109
110 while (number_of_bits != 0) {
111 number_of_bits--;
112 remainder <<= 1;
113 remainder |= (data[array_index] & bitmask) >> bitshift;
114 bitmask >>= 1;
115 bitshift--;
116 if (bitmask == 0) {
117 bitmask = 0x80;
118 bitshift = 7;
119 array_index++;
120 }
121 if ((remainder & 0x100) == 0x100)
122 remainder ^= 0xd5;
123 }
124
125 number_of_bits = 8;
126 while (number_of_bits != 0) {
127 number_of_bits--;
128 remainder <<= 1;
129 if ((remainder & 0x100) != 0)
130 remainder ^= 0xd5;
131 }
132
133 return remainder & 0xff;
134 }
135 static inline u8 drm_dp_calc_sb_hdr_size(struct drm_dp_sideband_msg_hdr *hdr)
136 {
137 u8 size = 3;
138 size += (hdr->lct / 2);
139 return size;
140 }
141
142 static void drm_dp_encode_sideband_msg_hdr(struct drm_dp_sideband_msg_hdr *hdr,
143 u8 *buf, int *len)
144 {
145 int idx = 0;
146 int i;
147 u8 crc4;
148 buf[idx++] = ((hdr->lct & 0xf) << 4) | (hdr->lcr & 0xf);
149 for (i = 0; i < (hdr->lct / 2); i++)
150 buf[idx++] = hdr->rad[i];
151 buf[idx++] = (hdr->broadcast << 7) | (hdr->path_msg << 6) |
152 (hdr->msg_len & 0x3f);
153 buf[idx++] = (hdr->somt << 7) | (hdr->eomt << 6) | (hdr->seqno << 4);
154
155 crc4 = drm_dp_msg_header_crc4(buf, (idx * 2) - 1);
156 buf[idx - 1] |= (crc4 & 0xf);
157
158 *len = idx;
159 }
160
161 static bool drm_dp_decode_sideband_msg_hdr(struct drm_dp_sideband_msg_hdr *hdr,
162 u8 *buf, int buflen, u8 *hdrlen)
163 {
164 u8 crc4;
165 u8 len;
166 int i;
167 u8 idx;
168 if (buf[0] == 0)
169 return false;
170 len = 3;
171 len += ((buf[0] & 0xf0) >> 4) / 2;
172 if (len > buflen)
173 return false;
174 crc4 = drm_dp_msg_header_crc4(buf, (len * 2) - 1);
175
176 if ((crc4 & 0xf) != (buf[len - 1] & 0xf)) {
177 DRM_DEBUG_KMS("crc4 mismatch 0x%x 0x%x\n", crc4, buf[len - 1]);
178 return false;
179 }
180
181 hdr->lct = (buf[0] & 0xf0) >> 4;
182 hdr->lcr = (buf[0] & 0xf);
183 idx = 1;
184 for (i = 0; i < (hdr->lct / 2); i++)
185 hdr->rad[i] = buf[idx++];
186 hdr->broadcast = (buf[idx] >> 7) & 0x1;
187 hdr->path_msg = (buf[idx] >> 6) & 0x1;
188 hdr->msg_len = buf[idx] & 0x3f;
189 idx++;
190 hdr->somt = (buf[idx] >> 7) & 0x1;
191 hdr->eomt = (buf[idx] >> 6) & 0x1;
192 hdr->seqno = (buf[idx] >> 4) & 0x1;
193 idx++;
194 *hdrlen = idx;
195 return true;
196 }
197
198 static void drm_dp_encode_sideband_req(struct drm_dp_sideband_msg_req_body *req,
199 struct drm_dp_sideband_msg_tx *raw)
200 {
201 int idx = 0;
202 int i;
203 u8 *buf = raw->msg;
204 buf[idx++] = req->req_type & 0x7f;
205
206 switch (req->req_type) {
207 case DP_ENUM_PATH_RESOURCES:
208 buf[idx] = (req->u.port_num.port_number & 0xf) << 4;
209 idx++;
210 break;
211 case DP_ALLOCATE_PAYLOAD:
212 buf[idx] = (req->u.allocate_payload.port_number & 0xf) << 4 |
213 (req->u.allocate_payload.number_sdp_streams & 0xf);
214 idx++;
215 buf[idx] = (req->u.allocate_payload.vcpi & 0x7f);
216 idx++;
217 buf[idx] = (req->u.allocate_payload.pbn >> 8);
218 idx++;
219 buf[idx] = (req->u.allocate_payload.pbn & 0xff);
220 idx++;
221 for (i = 0; i < req->u.allocate_payload.number_sdp_streams / 2; i++) {
222 buf[idx] = ((req->u.allocate_payload.sdp_stream_sink[i * 2] & 0xf) << 4) |
223 (req->u.allocate_payload.sdp_stream_sink[i * 2 + 1] & 0xf);
224 idx++;
225 }
226 if (req->u.allocate_payload.number_sdp_streams & 1) {
227 i = req->u.allocate_payload.number_sdp_streams - 1;
228 buf[idx] = (req->u.allocate_payload.sdp_stream_sink[i] & 0xf) << 4;
229 idx++;
230 }
231 break;
232 case DP_QUERY_PAYLOAD:
233 buf[idx] = (req->u.query_payload.port_number & 0xf) << 4;
234 idx++;
235 buf[idx] = (req->u.query_payload.vcpi & 0x7f);
236 idx++;
237 break;
238 case DP_REMOTE_DPCD_READ:
239 buf[idx] = (req->u.dpcd_read.port_number & 0xf) << 4;
240 buf[idx] |= ((req->u.dpcd_read.dpcd_address & 0xf0000) >> 16) & 0xf;
241 idx++;
242 buf[idx] = (req->u.dpcd_read.dpcd_address & 0xff00) >> 8;
243 idx++;
244 buf[idx] = (req->u.dpcd_read.dpcd_address & 0xff);
245 idx++;
246 buf[idx] = (req->u.dpcd_read.num_bytes);
247 idx++;
248 break;
249
250 case DP_REMOTE_DPCD_WRITE:
251 buf[idx] = (req->u.dpcd_write.port_number & 0xf) << 4;
252 buf[idx] |= ((req->u.dpcd_write.dpcd_address & 0xf0000) >> 16) & 0xf;
253 idx++;
254 buf[idx] = (req->u.dpcd_write.dpcd_address & 0xff00) >> 8;
255 idx++;
256 buf[idx] = (req->u.dpcd_write.dpcd_address & 0xff);
257 idx++;
258 buf[idx] = (req->u.dpcd_write.num_bytes);
259 idx++;
260 memcpy(&buf[idx], req->u.dpcd_write.bytes, req->u.dpcd_write.num_bytes);
261 idx += req->u.dpcd_write.num_bytes;
262 break;
263 case DP_REMOTE_I2C_READ:
264 buf[idx] = (req->u.i2c_read.port_number & 0xf) << 4;
265 buf[idx] |= (req->u.i2c_read.num_transactions & 0x3);
266 idx++;
267 for (i = 0; i < (req->u.i2c_read.num_transactions & 0x3); i++) {
268 buf[idx] = req->u.i2c_read.transactions[i].i2c_dev_id & 0x7f;
269 idx++;
270 buf[idx] = req->u.i2c_read.transactions[i].num_bytes;
271 idx++;
272 memcpy(&buf[idx], req->u.i2c_read.transactions[i].bytes, req->u.i2c_read.transactions[i].num_bytes);
273 idx += req->u.i2c_read.transactions[i].num_bytes;
274
275 buf[idx] = (req->u.i2c_read.transactions[i].no_stop_bit & 0x1) << 5;
276 buf[idx] |= (req->u.i2c_read.transactions[i].i2c_transaction_delay & 0xf);
277 idx++;
278 }
279 buf[idx] = (req->u.i2c_read.read_i2c_device_id) & 0x7f;
280 idx++;
281 buf[idx] = (req->u.i2c_read.num_bytes_read);
282 idx++;
283 break;
284
285 case DP_REMOTE_I2C_WRITE:
286 buf[idx] = (req->u.i2c_write.port_number & 0xf) << 4;
287 idx++;
288 buf[idx] = (req->u.i2c_write.write_i2c_device_id) & 0x7f;
289 idx++;
290 buf[idx] = (req->u.i2c_write.num_bytes);
291 idx++;
292 memcpy(&buf[idx], req->u.i2c_write.bytes, req->u.i2c_write.num_bytes);
293 idx += req->u.i2c_write.num_bytes;
294 break;
295 }
296 raw->cur_len = idx;
297 }
298
299 static void drm_dp_crc_sideband_chunk_req(u8 *msg, u8 len)
300 {
301 u8 crc4;
302 crc4 = drm_dp_msg_data_crc4(msg, len);
303 msg[len] = crc4;
304 }
305
306 static void drm_dp_encode_sideband_reply(struct drm_dp_sideband_msg_reply_body *rep,
307 struct drm_dp_sideband_msg_tx *raw)
308 {
309 int idx = 0;
310 u8 *buf = raw->msg;
311
312 buf[idx++] = (rep->reply_type & 0x1) << 7 | (rep->req_type & 0x7f);
313
314 raw->cur_len = idx;
315 }
316
317 /* this adds a chunk of msg to the builder to get the final msg */
318 static bool drm_dp_sideband_msg_build(struct drm_dp_sideband_msg_rx *msg,
319 u8 *replybuf, u8 replybuflen, bool hdr)
320 {
321 int ret;
322 u8 crc4;
323
324 if (hdr) {
325 u8 hdrlen;
326 struct drm_dp_sideband_msg_hdr recv_hdr;
327 ret = drm_dp_decode_sideband_msg_hdr(&recv_hdr, replybuf, replybuflen, &hdrlen);
328 if (ret == false) {
329 print_hex_dump(KERN_DEBUG, "failed hdr", DUMP_PREFIX_NONE, 16, 1, replybuf, replybuflen, false);
330 return false;
331 }
332
333 /* get length contained in this portion */
334 msg->curchunk_len = recv_hdr.msg_len;
335 msg->curchunk_hdrlen = hdrlen;
336
337 /* we have already gotten an somt - don't bother parsing */
338 if (recv_hdr.somt && msg->have_somt)
339 return false;
340
341 if (recv_hdr.somt) {
342 memcpy(&msg->initial_hdr, &recv_hdr, sizeof(struct drm_dp_sideband_msg_hdr));
343 msg->have_somt = true;
344 }
345 if (recv_hdr.eomt)
346 msg->have_eomt = true;
347
348 /* copy the bytes for the remainder of this header chunk */
349 msg->curchunk_idx = min(msg->curchunk_len, (u8)(replybuflen - hdrlen));
350 memcpy(&msg->chunk[0], replybuf + hdrlen, msg->curchunk_idx);
351 } else {
352 memcpy(&msg->chunk[msg->curchunk_idx], replybuf, replybuflen);
353 msg->curchunk_idx += replybuflen;
354 }
355
356 if (msg->curchunk_idx >= msg->curchunk_len) {
357 /* do CRC */
358 crc4 = drm_dp_msg_data_crc4(msg->chunk, msg->curchunk_len - 1);
359 /* copy chunk into bigger msg */
360 memcpy(&msg->msg[msg->curlen], msg->chunk, msg->curchunk_len - 1);
361 msg->curlen += msg->curchunk_len - 1;
362 }
363 return true;
364 }
365
366 static bool drm_dp_sideband_parse_link_address(struct drm_dp_sideband_msg_rx *raw,
367 struct drm_dp_sideband_msg_reply_body *repmsg)
368 {
369 int idx = 1;
370 int i;
371 memcpy(repmsg->u.link_addr.guid, &raw->msg[idx], 16);
372 idx += 16;
373 repmsg->u.link_addr.nports = raw->msg[idx] & 0xf;
374 idx++;
375 if (idx > raw->curlen)
376 goto fail_len;
377 for (i = 0; i < repmsg->u.link_addr.nports; i++) {
378 if (raw->msg[idx] & 0x80)
379 repmsg->u.link_addr.ports[i].input_port = 1;
380
381 repmsg->u.link_addr.ports[i].peer_device_type = (raw->msg[idx] >> 4) & 0x7;
382 repmsg->u.link_addr.ports[i].port_number = (raw->msg[idx] & 0xf);
383
384 idx++;
385 if (idx > raw->curlen)
386 goto fail_len;
387 repmsg->u.link_addr.ports[i].mcs = (raw->msg[idx] >> 7) & 0x1;
388 repmsg->u.link_addr.ports[i].ddps = (raw->msg[idx] >> 6) & 0x1;
389 if (repmsg->u.link_addr.ports[i].input_port == 0)
390 repmsg->u.link_addr.ports[i].legacy_device_plug_status = (raw->msg[idx] >> 5) & 0x1;
391 idx++;
392 if (idx > raw->curlen)
393 goto fail_len;
394 if (repmsg->u.link_addr.ports[i].input_port == 0) {
395 repmsg->u.link_addr.ports[i].dpcd_revision = (raw->msg[idx]);
396 idx++;
397 if (idx > raw->curlen)
398 goto fail_len;
399 memcpy(repmsg->u.link_addr.ports[i].peer_guid, &raw->msg[idx], 16);
400 idx += 16;
401 if (idx > raw->curlen)
402 goto fail_len;
403 repmsg->u.link_addr.ports[i].num_sdp_streams = (raw->msg[idx] >> 4) & 0xf;
404 repmsg->u.link_addr.ports[i].num_sdp_stream_sinks = (raw->msg[idx] & 0xf);
405 idx++;
406
407 }
408 if (idx > raw->curlen)
409 goto fail_len;
410 }
411
412 return true;
413 fail_len:
414 DRM_DEBUG_KMS("link address reply parse length fail %d %d\n", idx, raw->curlen);
415 return false;
416 }
417
418 static bool drm_dp_sideband_parse_remote_dpcd_read(struct drm_dp_sideband_msg_rx *raw,
419 struct drm_dp_sideband_msg_reply_body *repmsg)
420 {
421 int idx = 1;
422 repmsg->u.remote_dpcd_read_ack.port_number = raw->msg[idx] & 0xf;
423 idx++;
424 if (idx > raw->curlen)
425 goto fail_len;
426 repmsg->u.remote_dpcd_read_ack.num_bytes = raw->msg[idx];
427 if (idx > raw->curlen)
428 goto fail_len;
429
430 memcpy(repmsg->u.remote_dpcd_read_ack.bytes, &raw->msg[idx], repmsg->u.remote_dpcd_read_ack.num_bytes);
431 return true;
432 fail_len:
433 DRM_DEBUG_KMS("link address reply parse length fail %d %d\n", idx, raw->curlen);
434 return false;
435 }
436
437 static bool drm_dp_sideband_parse_remote_dpcd_write(struct drm_dp_sideband_msg_rx *raw,
438 struct drm_dp_sideband_msg_reply_body *repmsg)
439 {
440 int idx = 1;
441 repmsg->u.remote_dpcd_write_ack.port_number = raw->msg[idx] & 0xf;
442 idx++;
443 if (idx > raw->curlen)
444 goto fail_len;
445 return true;
446 fail_len:
447 DRM_DEBUG_KMS("parse length fail %d %d\n", idx, raw->curlen);
448 return false;
449 }
450
451 static bool drm_dp_sideband_parse_remote_i2c_read_ack(struct drm_dp_sideband_msg_rx *raw,
452 struct drm_dp_sideband_msg_reply_body *repmsg)
453 {
454 int idx = 1;
455
456 repmsg->u.remote_i2c_read_ack.port_number = (raw->msg[idx] & 0xf);
457 idx++;
458 if (idx > raw->curlen)
459 goto fail_len;
460 repmsg->u.remote_i2c_read_ack.num_bytes = raw->msg[idx];
461 idx++;
462 /* TODO check */
463 memcpy(repmsg->u.remote_i2c_read_ack.bytes, &raw->msg[idx], repmsg->u.remote_i2c_read_ack.num_bytes);
464 return true;
465 fail_len:
466 DRM_DEBUG_KMS("remote i2c reply parse length fail %d %d\n", idx, raw->curlen);
467 return false;
468 }
469
470 static bool drm_dp_sideband_parse_enum_path_resources_ack(struct drm_dp_sideband_msg_rx *raw,
471 struct drm_dp_sideband_msg_reply_body *repmsg)
472 {
473 int idx = 1;
474 repmsg->u.path_resources.port_number = (raw->msg[idx] >> 4) & 0xf;
475 idx++;
476 if (idx > raw->curlen)
477 goto fail_len;
478 repmsg->u.path_resources.full_payload_bw_number = (raw->msg[idx] << 8) | (raw->msg[idx+1]);
479 idx += 2;
480 if (idx > raw->curlen)
481 goto fail_len;
482 repmsg->u.path_resources.avail_payload_bw_number = (raw->msg[idx] << 8) | (raw->msg[idx+1]);
483 idx += 2;
484 if (idx > raw->curlen)
485 goto fail_len;
486 return true;
487 fail_len:
488 DRM_DEBUG_KMS("enum resource parse length fail %d %d\n", idx, raw->curlen);
489 return false;
490 }
491
492 static bool drm_dp_sideband_parse_allocate_payload_ack(struct drm_dp_sideband_msg_rx *raw,
493 struct drm_dp_sideband_msg_reply_body *repmsg)
494 {
495 int idx = 1;
496 repmsg->u.allocate_payload.port_number = (raw->msg[idx] >> 4) & 0xf;
497 idx++;
498 if (idx > raw->curlen)
499 goto fail_len;
500 repmsg->u.allocate_payload.vcpi = raw->msg[idx];
501 idx++;
502 if (idx > raw->curlen)
503 goto fail_len;
504 repmsg->u.allocate_payload.allocated_pbn = (raw->msg[idx] << 8) | (raw->msg[idx+1]);
505 idx += 2;
506 if (idx > raw->curlen)
507 goto fail_len;
508 return true;
509 fail_len:
510 DRM_DEBUG_KMS("allocate payload parse length fail %d %d\n", idx, raw->curlen);
511 return false;
512 }
513
514 static bool drm_dp_sideband_parse_query_payload_ack(struct drm_dp_sideband_msg_rx *raw,
515 struct drm_dp_sideband_msg_reply_body *repmsg)
516 {
517 int idx = 1;
518 repmsg->u.query_payload.port_number = (raw->msg[idx] >> 4) & 0xf;
519 idx++;
520 if (idx > raw->curlen)
521 goto fail_len;
522 repmsg->u.query_payload.allocated_pbn = (raw->msg[idx] << 8) | (raw->msg[idx + 1]);
523 idx += 2;
524 if (idx > raw->curlen)
525 goto fail_len;
526 return true;
527 fail_len:
528 DRM_DEBUG_KMS("query payload parse length fail %d %d\n", idx, raw->curlen);
529 return false;
530 }
531
532 static bool drm_dp_sideband_parse_reply(struct drm_dp_sideband_msg_rx *raw,
533 struct drm_dp_sideband_msg_reply_body *msg)
534 {
535 memset(msg, 0, sizeof(*msg));
536 msg->reply_type = (raw->msg[0] & 0x80) >> 7;
537 msg->req_type = (raw->msg[0] & 0x7f);
538
539 if (msg->reply_type) {
540 memcpy(msg->u.nak.guid, &raw->msg[1], 16);
541 msg->u.nak.reason = raw->msg[17];
542 msg->u.nak.nak_data = raw->msg[18];
543 return false;
544 }
545
546 switch (msg->req_type) {
547 case DP_LINK_ADDRESS:
548 return drm_dp_sideband_parse_link_address(raw, msg);
549 case DP_QUERY_PAYLOAD:
550 return drm_dp_sideband_parse_query_payload_ack(raw, msg);
551 case DP_REMOTE_DPCD_READ:
552 return drm_dp_sideband_parse_remote_dpcd_read(raw, msg);
553 case DP_REMOTE_DPCD_WRITE:
554 return drm_dp_sideband_parse_remote_dpcd_write(raw, msg);
555 case DP_REMOTE_I2C_READ:
556 return drm_dp_sideband_parse_remote_i2c_read_ack(raw, msg);
557 case DP_ENUM_PATH_RESOURCES:
558 return drm_dp_sideband_parse_enum_path_resources_ack(raw, msg);
559 case DP_ALLOCATE_PAYLOAD:
560 return drm_dp_sideband_parse_allocate_payload_ack(raw, msg);
561 default:
562 DRM_ERROR("Got unknown reply 0x%02x\n", msg->req_type);
563 return false;
564 }
565 }
566
567 static bool drm_dp_sideband_parse_connection_status_notify(struct drm_dp_sideband_msg_rx *raw,
568 struct drm_dp_sideband_msg_req_body *msg)
569 {
570 int idx = 1;
571
572 msg->u.conn_stat.port_number = (raw->msg[idx] & 0xf0) >> 4;
573 idx++;
574 if (idx > raw->curlen)
575 goto fail_len;
576
577 memcpy(msg->u.conn_stat.guid, &raw->msg[idx], 16);
578 idx += 16;
579 if (idx > raw->curlen)
580 goto fail_len;
581
582 msg->u.conn_stat.legacy_device_plug_status = (raw->msg[idx] >> 6) & 0x1;
583 msg->u.conn_stat.displayport_device_plug_status = (raw->msg[idx] >> 5) & 0x1;
584 msg->u.conn_stat.message_capability_status = (raw->msg[idx] >> 4) & 0x1;
585 msg->u.conn_stat.input_port = (raw->msg[idx] >> 3) & 0x1;
586 msg->u.conn_stat.peer_device_type = (raw->msg[idx] & 0x7);
587 idx++;
588 return true;
589 fail_len:
590 DRM_DEBUG_KMS("connection status reply parse length fail %d %d\n", idx, raw->curlen);
591 return false;
592 }
593
594 static bool drm_dp_sideband_parse_resource_status_notify(struct drm_dp_sideband_msg_rx *raw,
595 struct drm_dp_sideband_msg_req_body *msg)
596 {
597 int idx = 1;
598
599 msg->u.resource_stat.port_number = (raw->msg[idx] & 0xf0) >> 4;
600 idx++;
601 if (idx > raw->curlen)
602 goto fail_len;
603
604 memcpy(msg->u.resource_stat.guid, &raw->msg[idx], 16);
605 idx += 16;
606 if (idx > raw->curlen)
607 goto fail_len;
608
609 msg->u.resource_stat.available_pbn = (raw->msg[idx] << 8) | (raw->msg[idx + 1]);
610 idx++;
611 return true;
612 fail_len:
613 DRM_DEBUG_KMS("resource status reply parse length fail %d %d\n", idx, raw->curlen);
614 return false;
615 }
616
617 static bool drm_dp_sideband_parse_req(struct drm_dp_sideband_msg_rx *raw,
618 struct drm_dp_sideband_msg_req_body *msg)
619 {
620 memset(msg, 0, sizeof(*msg));
621 msg->req_type = (raw->msg[0] & 0x7f);
622
623 switch (msg->req_type) {
624 case DP_CONNECTION_STATUS_NOTIFY:
625 return drm_dp_sideband_parse_connection_status_notify(raw, msg);
626 case DP_RESOURCE_STATUS_NOTIFY:
627 return drm_dp_sideband_parse_resource_status_notify(raw, msg);
628 default:
629 DRM_ERROR("Got unknown request 0x%02x\n", msg->req_type);
630 return false;
631 }
632 }
633
634 static int build_dpcd_write(struct drm_dp_sideband_msg_tx *msg, u8 port_num, u32 offset, u8 num_bytes, u8 *bytes)
635 {
636 struct drm_dp_sideband_msg_req_body req;
637
638 req.req_type = DP_REMOTE_DPCD_WRITE;
639 req.u.dpcd_write.port_number = port_num;
640 req.u.dpcd_write.dpcd_address = offset;
641 req.u.dpcd_write.num_bytes = num_bytes;
642 req.u.dpcd_write.bytes = bytes;
643 drm_dp_encode_sideband_req(&req, msg);
644
645 return 0;
646 }
647
648 static int build_link_address(struct drm_dp_sideband_msg_tx *msg)
649 {
650 struct drm_dp_sideband_msg_req_body req;
651
652 req.req_type = DP_LINK_ADDRESS;
653 drm_dp_encode_sideband_req(&req, msg);
654 return 0;
655 }
656
657 static int build_enum_path_resources(struct drm_dp_sideband_msg_tx *msg, int port_num)
658 {
659 struct drm_dp_sideband_msg_req_body req;
660
661 req.req_type = DP_ENUM_PATH_RESOURCES;
662 req.u.port_num.port_number = port_num;
663 drm_dp_encode_sideband_req(&req, msg);
664 msg->path_msg = true;
665 return 0;
666 }
667
668 static int build_allocate_payload(struct drm_dp_sideband_msg_tx *msg, int port_num,
669 u8 vcpi, uint16_t pbn,
670 u8 number_sdp_streams,
671 u8 *sdp_stream_sink)
672 {
673 struct drm_dp_sideband_msg_req_body req;
674 memset(&req, 0, sizeof(req));
675 req.req_type = DP_ALLOCATE_PAYLOAD;
676 req.u.allocate_payload.port_number = port_num;
677 req.u.allocate_payload.vcpi = vcpi;
678 req.u.allocate_payload.pbn = pbn;
679 req.u.allocate_payload.number_sdp_streams = number_sdp_streams;
680 memcpy(req.u.allocate_payload.sdp_stream_sink, sdp_stream_sink,
681 number_sdp_streams);
682 drm_dp_encode_sideband_req(&req, msg);
683 msg->path_msg = true;
684 return 0;
685 }
686
687 static int drm_dp_mst_assign_payload_id(struct drm_dp_mst_topology_mgr *mgr,
688 struct drm_dp_vcpi *vcpi)
689 {
690 int ret, vcpi_ret;
691
692 mutex_lock(&mgr->payload_lock);
693 ret = find_first_zero_bit(&mgr->payload_mask, mgr->max_payloads + 1);
694 if (ret > mgr->max_payloads) {
695 ret = -EINVAL;
696 DRM_DEBUG_KMS("out of payload ids %d\n", ret);
697 goto out_unlock;
698 }
699
700 vcpi_ret = find_first_zero_bit(&mgr->vcpi_mask, mgr->max_payloads + 1);
701 if (vcpi_ret > mgr->max_payloads) {
702 ret = -EINVAL;
703 DRM_DEBUG_KMS("out of vcpi ids %d\n", ret);
704 goto out_unlock;
705 }
706
707 set_bit(ret, &mgr->payload_mask);
708 set_bit(vcpi_ret, &mgr->vcpi_mask);
709 vcpi->vcpi = vcpi_ret + 1;
710 mgr->proposed_vcpis[ret - 1] = vcpi;
711 out_unlock:
712 mutex_unlock(&mgr->payload_lock);
713 return ret;
714 }
715
716 static void drm_dp_mst_put_payload_id(struct drm_dp_mst_topology_mgr *mgr,
717 int vcpi)
718 {
719 int i;
720 if (vcpi == 0)
721 return;
722
723 mutex_lock(&mgr->payload_lock);
724 DRM_DEBUG_KMS("putting payload %d\n", vcpi);
725 clear_bit(vcpi - 1, &mgr->vcpi_mask);
726
727 for (i = 0; i < mgr->max_payloads; i++) {
728 if (mgr->proposed_vcpis[i])
729 if (mgr->proposed_vcpis[i]->vcpi == vcpi) {
730 mgr->proposed_vcpis[i] = NULL;
731 clear_bit(i + 1, &mgr->payload_mask);
732 }
733 }
734 mutex_unlock(&mgr->payload_lock);
735 }
736
737 static bool check_txmsg_state(struct drm_dp_mst_topology_mgr *mgr,
738 struct drm_dp_sideband_msg_tx *txmsg)
739 {
740 bool ret;
741
742 /*
743 * All updates to txmsg->state are protected by mgr->qlock, and the two
744 * cases we check here are terminal states. For those the barriers
745 * provided by the wake_up/wait_event pair are enough.
746 */
747 ret = (txmsg->state == DRM_DP_SIDEBAND_TX_RX ||
748 txmsg->state == DRM_DP_SIDEBAND_TX_TIMEOUT);
749 return ret;
750 }
751
752 static int drm_dp_mst_wait_tx_reply(struct drm_dp_mst_branch *mstb,
753 struct drm_dp_sideband_msg_tx *txmsg)
754 {
755 struct drm_dp_mst_topology_mgr *mgr = mstb->mgr;
756 int ret;
757
758 ret = wait_event_timeout(mgr->tx_waitq,
759 check_txmsg_state(mgr, txmsg),
760 (4 * HZ));
761 mutex_lock(&mstb->mgr->qlock);
762 if (ret > 0) {
763 if (txmsg->state == DRM_DP_SIDEBAND_TX_TIMEOUT) {
764 ret = -EIO;
765 goto out;
766 }
767 } else {
768 DRM_DEBUG_KMS("timedout msg send %p %d %d\n", txmsg, txmsg->state, txmsg->seqno);
769
770 /* dump some state */
771 ret = -EIO;
772
773 /* remove from q */
774 if (txmsg->state == DRM_DP_SIDEBAND_TX_QUEUED ||
775 txmsg->state == DRM_DP_SIDEBAND_TX_START_SEND) {
776 list_del(&txmsg->next);
777 }
778
779 if (txmsg->state == DRM_DP_SIDEBAND_TX_START_SEND ||
780 txmsg->state == DRM_DP_SIDEBAND_TX_SENT) {
781 mstb->tx_slots[txmsg->seqno] = NULL;
782 }
783 }
784 out:
785 mutex_unlock(&mgr->qlock);
786
787 return ret;
788 }
789
790 static struct drm_dp_mst_branch *drm_dp_add_mst_branch_device(u8 lct, u8 *rad)
791 {
792 struct drm_dp_mst_branch *mstb;
793
794 mstb = kzalloc(sizeof(*mstb), GFP_KERNEL);
795 if (!mstb)
796 return NULL;
797
798 mstb->lct = lct;
799 if (lct > 1)
800 memcpy(mstb->rad, rad, lct / 2);
801 INIT_LIST_HEAD(&mstb->ports);
802 kref_init(&mstb->kref);
803 return mstb;
804 }
805
806 static void drm_dp_free_mst_port(struct kref *kref);
807
808 static void drm_dp_free_mst_branch_device(struct kref *kref)
809 {
810 struct drm_dp_mst_branch *mstb = container_of(kref, struct drm_dp_mst_branch, kref);
811 if (mstb->port_parent) {
812 if (list_empty(&mstb->port_parent->next))
813 kref_put(&mstb->port_parent->kref, drm_dp_free_mst_port);
814 }
815 kfree(mstb);
816 }
817
818 static void drm_dp_destroy_mst_branch_device(struct kref *kref)
819 {
820 struct drm_dp_mst_branch *mstb = container_of(kref, struct drm_dp_mst_branch, kref);
821 struct drm_dp_mst_port *port, *tmp;
822 bool wake_tx = false;
823
824 /*
825 * init kref again to be used by ports to remove mst branch when it is
826 * not needed anymore
827 */
828 kref_init(kref);
829
830 if (mstb->port_parent && list_empty(&mstb->port_parent->next))
831 kref_get(&mstb->port_parent->kref);
832
833 /*
834 * destroy all ports - don't need lock
835 * as there are no more references to the mst branch
836 * device at this point.
837 */
838 list_for_each_entry_safe(port, tmp, &mstb->ports, next) {
839 list_del(&port->next);
840 drm_dp_put_port(port);
841 }
842
843 /* drop any tx slots msg */
844 mutex_lock(&mstb->mgr->qlock);
845 if (mstb->tx_slots[0]) {
846 mstb->tx_slots[0]->state = DRM_DP_SIDEBAND_TX_TIMEOUT;
847 mstb->tx_slots[0] = NULL;
848 wake_tx = true;
849 }
850 if (mstb->tx_slots[1]) {
851 mstb->tx_slots[1]->state = DRM_DP_SIDEBAND_TX_TIMEOUT;
852 mstb->tx_slots[1] = NULL;
853 wake_tx = true;
854 }
855 mutex_unlock(&mstb->mgr->qlock);
856
857 if (wake_tx)
858 wake_up(&mstb->mgr->tx_waitq);
859
860 kref_put(kref, drm_dp_free_mst_branch_device);
861 }
862
863 static void drm_dp_put_mst_branch_device(struct drm_dp_mst_branch *mstb)
864 {
865 kref_put(&mstb->kref, drm_dp_destroy_mst_branch_device);
866 }
867
868
869 static void drm_dp_port_teardown_pdt(struct drm_dp_mst_port *port, int old_pdt)
870 {
871 struct drm_dp_mst_branch *mstb;
872
873 switch (old_pdt) {
874 case DP_PEER_DEVICE_DP_LEGACY_CONV:
875 case DP_PEER_DEVICE_SST_SINK:
876 /* remove i2c over sideband */
877 drm_dp_mst_unregister_i2c_bus(&port->aux);
878 break;
879 case DP_PEER_DEVICE_MST_BRANCHING:
880 mstb = port->mstb;
881 port->mstb = NULL;
882 drm_dp_put_mst_branch_device(mstb);
883 break;
884 }
885 }
886
887 static void drm_dp_destroy_port(struct kref *kref)
888 {
889 struct drm_dp_mst_port *port = container_of(kref, struct drm_dp_mst_port, kref);
890 struct drm_dp_mst_topology_mgr *mgr = port->mgr;
891
892 if (!port->input) {
893 port->vcpi.num_slots = 0;
894
895 kfree(port->cached_edid);
896
897 /*
898 * The only time we don't have a connector
899 * on an output port is if the connector init
900 * fails.
901 */
902 if (port->connector) {
903 /* we can't destroy the connector here, as
904 * we might be holding the mode_config.mutex
905 * from an EDID retrieval */
906
907 mutex_lock(&mgr->destroy_connector_lock);
908 kref_get(&port->parent->kref);
909 list_add(&port->next, &mgr->destroy_connector_list);
910 mutex_unlock(&mgr->destroy_connector_lock);
911 schedule_work(&mgr->destroy_connector_work);
912 return;
913 }
914 /* no need to clean up vcpi
915 * as if we have no connector we never setup a vcpi */
916 drm_dp_port_teardown_pdt(port, port->pdt);
917 port->pdt = DP_PEER_DEVICE_NONE;
918 }
919 kfree(port);
920 }
921
922 static void drm_dp_put_port(struct drm_dp_mst_port *port)
923 {
924 kref_put(&port->kref, drm_dp_destroy_port);
925 }
926
927 static struct drm_dp_mst_branch *drm_dp_mst_get_validated_mstb_ref_locked(struct drm_dp_mst_branch *mstb, struct drm_dp_mst_branch *to_find)
928 {
929 struct drm_dp_mst_port *port;
930 struct drm_dp_mst_branch *rmstb;
931 if (to_find == mstb) {
932 kref_get(&mstb->kref);
933 return mstb;
934 }
935 list_for_each_entry(port, &mstb->ports, next) {
936 if (port->mstb) {
937 rmstb = drm_dp_mst_get_validated_mstb_ref_locked(port->mstb, to_find);
938 if (rmstb)
939 return rmstb;
940 }
941 }
942 return NULL;
943 }
944
945 static struct drm_dp_mst_branch *drm_dp_get_validated_mstb_ref(struct drm_dp_mst_topology_mgr *mgr, struct drm_dp_mst_branch *mstb)
946 {
947 struct drm_dp_mst_branch *rmstb = NULL;
948 mutex_lock(&mgr->lock);
949 if (mgr->mst_primary)
950 rmstb = drm_dp_mst_get_validated_mstb_ref_locked(mgr->mst_primary, mstb);
951 mutex_unlock(&mgr->lock);
952 return rmstb;
953 }
954
955 static struct drm_dp_mst_port *drm_dp_mst_get_port_ref_locked(struct drm_dp_mst_branch *mstb, struct drm_dp_mst_port *to_find)
956 {
957 struct drm_dp_mst_port *port, *mport;
958
959 list_for_each_entry(port, &mstb->ports, next) {
960 if (port == to_find) {
961 kref_get(&port->kref);
962 return port;
963 }
964 if (port->mstb) {
965 mport = drm_dp_mst_get_port_ref_locked(port->mstb, to_find);
966 if (mport)
967 return mport;
968 }
969 }
970 return NULL;
971 }
972
973 static struct drm_dp_mst_port *drm_dp_get_validated_port_ref(struct drm_dp_mst_topology_mgr *mgr, struct drm_dp_mst_port *port)
974 {
975 struct drm_dp_mst_port *rport = NULL;
976 mutex_lock(&mgr->lock);
977 if (mgr->mst_primary)
978 rport = drm_dp_mst_get_port_ref_locked(mgr->mst_primary, port);
979 mutex_unlock(&mgr->lock);
980 return rport;
981 }
982
983 static struct drm_dp_mst_port *drm_dp_get_port(struct drm_dp_mst_branch *mstb, u8 port_num)
984 {
985 struct drm_dp_mst_port *port;
986
987 list_for_each_entry(port, &mstb->ports, next) {
988 if (port->port_num == port_num) {
989 kref_get(&port->kref);
990 return port;
991 }
992 }
993
994 return NULL;
995 }
996
997 /*
998 * calculate a new RAD for this MST branch device
999 * if parent has an LCT of 2 then it has 1 nibble of RAD,
1000 * if parent has an LCT of 3 then it has 2 nibbles of RAD,
1001 */
1002 static u8 drm_dp_calculate_rad(struct drm_dp_mst_port *port,
1003 u8 *rad)
1004 {
1005 int parent_lct = port->parent->lct;
1006 int shift = 4;
1007 int idx = (parent_lct - 1) / 2;
1008 if (parent_lct > 1) {
1009 memcpy(rad, port->parent->rad, idx + 1);
1010 shift = (parent_lct % 2) ? 4 : 0;
1011 } else
1012 rad[0] = 0;
1013
1014 rad[idx] |= port->port_num << shift;
1015 return parent_lct + 1;
1016 }
1017
1018 /*
1019 * return sends link address for new mstb
1020 */
1021 static bool drm_dp_port_setup_pdt(struct drm_dp_mst_port *port)
1022 {
1023 int ret;
1024 u8 rad[6], lct;
1025 bool send_link = false;
1026 switch (port->pdt) {
1027 case DP_PEER_DEVICE_DP_LEGACY_CONV:
1028 case DP_PEER_DEVICE_SST_SINK:
1029 /* add i2c over sideband */
1030 ret = drm_dp_mst_register_i2c_bus(&port->aux);
1031 break;
1032 case DP_PEER_DEVICE_MST_BRANCHING:
1033 lct = drm_dp_calculate_rad(port, rad);
1034
1035 port->mstb = drm_dp_add_mst_branch_device(lct, rad);
1036 port->mstb->mgr = port->mgr;
1037 port->mstb->port_parent = port;
1038
1039 send_link = true;
1040 break;
1041 }
1042 return send_link;
1043 }
1044
1045 static void drm_dp_check_mstb_guid(struct drm_dp_mst_branch *mstb, u8 *guid)
1046 {
1047 int ret;
1048
1049 memcpy(mstb->guid, guid, 16);
1050
1051 if (!drm_dp_validate_guid(mstb->mgr, mstb->guid)) {
1052 if (mstb->port_parent) {
1053 ret = drm_dp_send_dpcd_write(
1054 mstb->mgr,
1055 mstb->port_parent,
1056 DP_GUID,
1057 16,
1058 mstb->guid);
1059 } else {
1060
1061 ret = drm_dp_dpcd_write(
1062 mstb->mgr->aux,
1063 DP_GUID,
1064 mstb->guid,
1065 16);
1066 }
1067 }
1068 }
1069
1070 static void build_mst_prop_path(const struct drm_dp_mst_branch *mstb,
1071 int pnum,
1072 char *proppath,
1073 size_t proppath_size)
1074 {
1075 int i;
1076 char temp[8];
1077 snprintf(proppath, proppath_size, "mst:%d", mstb->mgr->conn_base_id);
1078 for (i = 0; i < (mstb->lct - 1); i++) {
1079 int shift = (i % 2) ? 0 : 4;
1080 int port_num = (mstb->rad[i / 2] >> shift) & 0xf;
1081 snprintf(temp, sizeof(temp), "-%d", port_num);
1082 strlcat(proppath, temp, proppath_size);
1083 }
1084 snprintf(temp, sizeof(temp), "-%d", pnum);
1085 strlcat(proppath, temp, proppath_size);
1086 }
1087
1088 static void drm_dp_add_port(struct drm_dp_mst_branch *mstb,
1089 struct device *dev,
1090 struct drm_dp_link_addr_reply_port *port_msg)
1091 {
1092 struct drm_dp_mst_port *port;
1093 bool ret;
1094 bool created = false;
1095 int old_pdt = 0;
1096 int old_ddps = 0;
1097 port = drm_dp_get_port(mstb, port_msg->port_number);
1098 if (!port) {
1099 port = kzalloc(sizeof(*port), GFP_KERNEL);
1100 if (!port)
1101 return;
1102 kref_init(&port->kref);
1103 port->parent = mstb;
1104 port->port_num = port_msg->port_number;
1105 port->mgr = mstb->mgr;
1106 port->aux.name = "DPMST";
1107 port->aux.dev = dev;
1108 created = true;
1109 } else {
1110 old_pdt = port->pdt;
1111 old_ddps = port->ddps;
1112 }
1113
1114 port->pdt = port_msg->peer_device_type;
1115 port->input = port_msg->input_port;
1116 port->mcs = port_msg->mcs;
1117 port->ddps = port_msg->ddps;
1118 port->ldps = port_msg->legacy_device_plug_status;
1119 port->dpcd_rev = port_msg->dpcd_revision;
1120 port->num_sdp_streams = port_msg->num_sdp_streams;
1121 port->num_sdp_stream_sinks = port_msg->num_sdp_stream_sinks;
1122
1123 /* manage mstb port lists with mgr lock - take a reference
1124 for this list */
1125 if (created) {
1126 mutex_lock(&mstb->mgr->lock);
1127 kref_get(&port->kref);
1128 list_add(&port->next, &mstb->ports);
1129 mutex_unlock(&mstb->mgr->lock);
1130 }
1131
1132 if (old_ddps != port->ddps) {
1133 if (port->ddps) {
1134 if (!port->input)
1135 drm_dp_send_enum_path_resources(mstb->mgr, mstb, port);
1136 } else {
1137 port->available_pbn = 0;
1138 }
1139 }
1140
1141 if (old_pdt != port->pdt && !port->input) {
1142 drm_dp_port_teardown_pdt(port, old_pdt);
1143
1144 ret = drm_dp_port_setup_pdt(port);
1145 if (ret == true)
1146 drm_dp_send_link_address(mstb->mgr, port->mstb);
1147 }
1148
1149 if (created && !port->input) {
1150 char proppath[255];
1151
1152 build_mst_prop_path(mstb, port->port_num, proppath, sizeof(proppath));
1153 port->connector = (*mstb->mgr->cbs->add_connector)(mstb->mgr, port, proppath);
1154 if (!port->connector) {
1155 /* remove it from the port list */
1156 mutex_lock(&mstb->mgr->lock);
1157 list_del(&port->next);
1158 mutex_unlock(&mstb->mgr->lock);
1159 /* drop port list reference */
1160 drm_dp_put_port(port);
1161 goto out;
1162 }
1163 if ((port->pdt == DP_PEER_DEVICE_DP_LEGACY_CONV ||
1164 port->pdt == DP_PEER_DEVICE_SST_SINK) &&
1165 port->port_num >= DP_MST_LOGICAL_PORT_0) {
1166 port->cached_edid = drm_get_edid(port->connector, &port->aux.ddc);
1167 drm_mode_connector_set_tile_property(port->connector);
1168 }
1169 (*mstb->mgr->cbs->register_connector)(port->connector);
1170 }
1171
1172 out:
1173 /* put reference to this port */
1174 drm_dp_put_port(port);
1175 }
1176
1177 static void drm_dp_update_port(struct drm_dp_mst_branch *mstb,
1178 struct drm_dp_connection_status_notify *conn_stat)
1179 {
1180 struct drm_dp_mst_port *port;
1181 int old_pdt;
1182 int old_ddps;
1183 bool dowork = false;
1184 port = drm_dp_get_port(mstb, conn_stat->port_number);
1185 if (!port)
1186 return;
1187
1188 old_ddps = port->ddps;
1189 old_pdt = port->pdt;
1190 port->pdt = conn_stat->peer_device_type;
1191 port->mcs = conn_stat->message_capability_status;
1192 port->ldps = conn_stat->legacy_device_plug_status;
1193 port->ddps = conn_stat->displayport_device_plug_status;
1194
1195 if (old_ddps != port->ddps) {
1196 if (port->ddps) {
1197 dowork = true;
1198 } else {
1199 port->available_pbn = 0;
1200 }
1201 }
1202 if (old_pdt != port->pdt && !port->input) {
1203 drm_dp_port_teardown_pdt(port, old_pdt);
1204
1205 if (drm_dp_port_setup_pdt(port))
1206 dowork = true;
1207 }
1208
1209 drm_dp_put_port(port);
1210 if (dowork)
1211 queue_work(system_long_wq, &mstb->mgr->work);
1212
1213 }
1214
1215 static struct drm_dp_mst_branch *drm_dp_get_mst_branch_device(struct drm_dp_mst_topology_mgr *mgr,
1216 u8 lct, u8 *rad)
1217 {
1218 struct drm_dp_mst_branch *mstb;
1219 struct drm_dp_mst_port *port;
1220 int i;
1221 /* find the port by iterating down */
1222
1223 mutex_lock(&mgr->lock);
1224 mstb = mgr->mst_primary;
1225
1226 for (i = 0; i < lct - 1; i++) {
1227 int shift = (i % 2) ? 0 : 4;
1228 int port_num = (rad[i / 2] >> shift) & 0xf;
1229
1230 list_for_each_entry(port, &mstb->ports, next) {
1231 if (port->port_num == port_num) {
1232 mstb = port->mstb;
1233 if (!mstb) {
1234 DRM_ERROR("failed to lookup MSTB with lct %d, rad %02x\n", lct, rad[0]);
1235 goto out;
1236 }
1237
1238 break;
1239 }
1240 }
1241 }
1242 kref_get(&mstb->kref);
1243 out:
1244 mutex_unlock(&mgr->lock);
1245 return mstb;
1246 }
1247
1248 static struct drm_dp_mst_branch *get_mst_branch_device_by_guid_helper(
1249 struct drm_dp_mst_branch *mstb,
1250 uint8_t *guid)
1251 {
1252 struct drm_dp_mst_branch *found_mstb;
1253 struct drm_dp_mst_port *port;
1254
1255 if (memcmp(mstb->guid, guid, 16) == 0)
1256 return mstb;
1257
1258
1259 list_for_each_entry(port, &mstb->ports, next) {
1260 if (!port->mstb)
1261 continue;
1262
1263 found_mstb = get_mst_branch_device_by_guid_helper(port->mstb, guid);
1264
1265 if (found_mstb)
1266 return found_mstb;
1267 }
1268
1269 return NULL;
1270 }
1271
1272 static struct drm_dp_mst_branch *drm_dp_get_mst_branch_device_by_guid(
1273 struct drm_dp_mst_topology_mgr *mgr,
1274 uint8_t *guid)
1275 {
1276 struct drm_dp_mst_branch *mstb;
1277
1278 /* find the port by iterating down */
1279 mutex_lock(&mgr->lock);
1280
1281 mstb = get_mst_branch_device_by_guid_helper(mgr->mst_primary, guid);
1282
1283 if (mstb)
1284 kref_get(&mstb->kref);
1285
1286 mutex_unlock(&mgr->lock);
1287 return mstb;
1288 }
1289
1290 static void drm_dp_check_and_send_link_address(struct drm_dp_mst_topology_mgr *mgr,
1291 struct drm_dp_mst_branch *mstb)
1292 {
1293 struct drm_dp_mst_port *port;
1294 struct drm_dp_mst_branch *mstb_child;
1295 if (!mstb->link_address_sent)
1296 drm_dp_send_link_address(mgr, mstb);
1297
1298 list_for_each_entry(port, &mstb->ports, next) {
1299 if (port->input)
1300 continue;
1301
1302 if (!port->ddps)
1303 continue;
1304
1305 if (!port->available_pbn)
1306 drm_dp_send_enum_path_resources(mgr, mstb, port);
1307
1308 if (port->mstb) {
1309 mstb_child = drm_dp_get_validated_mstb_ref(mgr, port->mstb);
1310 if (mstb_child) {
1311 drm_dp_check_and_send_link_address(mgr, mstb_child);
1312 drm_dp_put_mst_branch_device(mstb_child);
1313 }
1314 }
1315 }
1316 }
1317
1318 static void drm_dp_mst_link_probe_work(struct work_struct *work)
1319 {
1320 struct drm_dp_mst_topology_mgr *mgr = container_of(work, struct drm_dp_mst_topology_mgr, work);
1321 struct drm_dp_mst_branch *mstb;
1322
1323 mutex_lock(&mgr->lock);
1324 mstb = mgr->mst_primary;
1325 if (mstb) {
1326 kref_get(&mstb->kref);
1327 }
1328 mutex_unlock(&mgr->lock);
1329 if (mstb) {
1330 drm_dp_check_and_send_link_address(mgr, mstb);
1331 drm_dp_put_mst_branch_device(mstb);
1332 }
1333 }
1334
1335 static bool drm_dp_validate_guid(struct drm_dp_mst_topology_mgr *mgr,
1336 u8 *guid)
1337 {
1338 static u8 zero_guid[16];
1339
1340 if (!memcmp(guid, zero_guid, 16)) {
1341 u64 salt = get_jiffies_64();
1342 memcpy(&guid[0], &salt, sizeof(u64));
1343 memcpy(&guid[8], &salt, sizeof(u64));
1344 return false;
1345 }
1346 return true;
1347 }
1348
1349 #if 0
1350 static int build_dpcd_read(struct drm_dp_sideband_msg_tx *msg, u8 port_num, u32 offset, u8 num_bytes)
1351 {
1352 struct drm_dp_sideband_msg_req_body req;
1353
1354 req.req_type = DP_REMOTE_DPCD_READ;
1355 req.u.dpcd_read.port_number = port_num;
1356 req.u.dpcd_read.dpcd_address = offset;
1357 req.u.dpcd_read.num_bytes = num_bytes;
1358 drm_dp_encode_sideband_req(&req, msg);
1359
1360 return 0;
1361 }
1362 #endif
1363
1364 static int drm_dp_send_sideband_msg(struct drm_dp_mst_topology_mgr *mgr,
1365 bool up, u8 *msg, int len)
1366 {
1367 int ret;
1368 int regbase = up ? DP_SIDEBAND_MSG_UP_REP_BASE : DP_SIDEBAND_MSG_DOWN_REQ_BASE;
1369 int tosend, total, offset;
1370 int retries = 0;
1371
1372 retry:
1373 total = len;
1374 offset = 0;
1375 do {
1376 tosend = min3(mgr->max_dpcd_transaction_bytes, 16, total);
1377
1378 ret = drm_dp_dpcd_write(mgr->aux, regbase + offset,
1379 &msg[offset],
1380 tosend);
1381 if (ret != tosend) {
1382 if (ret == -EIO && retries < 5) {
1383 retries++;
1384 goto retry;
1385 }
1386 DRM_DEBUG_KMS("failed to dpcd write %d %d\n", tosend, ret);
1387
1388 return -EIO;
1389 }
1390 offset += tosend;
1391 total -= tosend;
1392 } while (total > 0);
1393 return 0;
1394 }
1395
1396 static int set_hdr_from_dst_qlock(struct drm_dp_sideband_msg_hdr *hdr,
1397 struct drm_dp_sideband_msg_tx *txmsg)
1398 {
1399 struct drm_dp_mst_branch *mstb = txmsg->dst;
1400 u8 req_type;
1401
1402 /* both msg slots are full */
1403 if (txmsg->seqno == -1) {
1404 if (mstb->tx_slots[0] && mstb->tx_slots[1]) {
1405 DRM_DEBUG_KMS("%s: failed to find slot\n", __func__);
1406 return -EAGAIN;
1407 }
1408 if (mstb->tx_slots[0] == NULL && mstb->tx_slots[1] == NULL) {
1409 txmsg->seqno = mstb->last_seqno;
1410 mstb->last_seqno ^= 1;
1411 } else if (mstb->tx_slots[0] == NULL)
1412 txmsg->seqno = 0;
1413 else
1414 txmsg->seqno = 1;
1415 mstb->tx_slots[txmsg->seqno] = txmsg;
1416 }
1417
1418 req_type = txmsg->msg[0] & 0x7f;
1419 if (req_type == DP_CONNECTION_STATUS_NOTIFY ||
1420 req_type == DP_RESOURCE_STATUS_NOTIFY)
1421 hdr->broadcast = 1;
1422 else
1423 hdr->broadcast = 0;
1424 hdr->path_msg = txmsg->path_msg;
1425 hdr->lct = mstb->lct;
1426 hdr->lcr = mstb->lct - 1;
1427 if (mstb->lct > 1)
1428 memcpy(hdr->rad, mstb->rad, mstb->lct / 2);
1429 hdr->seqno = txmsg->seqno;
1430 return 0;
1431 }
1432 /*
1433 * process a single block of the next message in the sideband queue
1434 */
1435 static int process_single_tx_qlock(struct drm_dp_mst_topology_mgr *mgr,
1436 struct drm_dp_sideband_msg_tx *txmsg,
1437 bool up)
1438 {
1439 u8 chunk[48];
1440 struct drm_dp_sideband_msg_hdr hdr;
1441 int len, space, idx, tosend;
1442 int ret;
1443
1444 memset(&hdr, 0, sizeof(struct drm_dp_sideband_msg_hdr));
1445
1446 if (txmsg->state == DRM_DP_SIDEBAND_TX_QUEUED) {
1447 txmsg->seqno = -1;
1448 txmsg->state = DRM_DP_SIDEBAND_TX_START_SEND;
1449 }
1450
1451 /* make hdr from dst mst - for replies use seqno
1452 otherwise assign one */
1453 ret = set_hdr_from_dst_qlock(&hdr, txmsg);
1454 if (ret < 0)
1455 return ret;
1456
1457 /* amount left to send in this message */
1458 len = txmsg->cur_len - txmsg->cur_offset;
1459
1460 /* 48 - sideband msg size - 1 byte for data CRC, x header bytes */
1461 space = 48 - 1 - drm_dp_calc_sb_hdr_size(&hdr);
1462
1463 tosend = min(len, space);
1464 if (len == txmsg->cur_len)
1465 hdr.somt = 1;
1466 if (space >= len)
1467 hdr.eomt = 1;
1468
1469
1470 hdr.msg_len = tosend + 1;
1471 drm_dp_encode_sideband_msg_hdr(&hdr, chunk, &idx);
1472 memcpy(&chunk[idx], &txmsg->msg[txmsg->cur_offset], tosend);
1473 /* add crc at end */
1474 drm_dp_crc_sideband_chunk_req(&chunk[idx], tosend);
1475 idx += tosend + 1;
1476
1477 ret = drm_dp_send_sideband_msg(mgr, up, chunk, idx);
1478 if (ret) {
1479 DRM_DEBUG_KMS("sideband msg failed to send\n");
1480 return ret;
1481 }
1482
1483 txmsg->cur_offset += tosend;
1484 if (txmsg->cur_offset == txmsg->cur_len) {
1485 txmsg->state = DRM_DP_SIDEBAND_TX_SENT;
1486 return 1;
1487 }
1488 return 0;
1489 }
1490
1491 static void process_single_down_tx_qlock(struct drm_dp_mst_topology_mgr *mgr)
1492 {
1493 struct drm_dp_sideband_msg_tx *txmsg;
1494 int ret;
1495
1496 WARN_ON(!mutex_is_locked(&mgr->qlock));
1497
1498 /* construct a chunk from the first msg in the tx_msg queue */
1499 if (list_empty(&mgr->tx_msg_downq))
1500 return;
1501
1502 txmsg = list_first_entry(&mgr->tx_msg_downq, struct drm_dp_sideband_msg_tx, next);
1503 ret = process_single_tx_qlock(mgr, txmsg, false);
1504 if (ret == 1) {
1505 /* txmsg is sent it should be in the slots now */
1506 list_del(&txmsg->next);
1507 } else if (ret) {
1508 DRM_DEBUG_KMS("failed to send msg in q %d\n", ret);
1509 list_del(&txmsg->next);
1510 if (txmsg->seqno != -1)
1511 txmsg->dst->tx_slots[txmsg->seqno] = NULL;
1512 txmsg->state = DRM_DP_SIDEBAND_TX_TIMEOUT;
1513 wake_up(&mgr->tx_waitq);
1514 }
1515 }
1516
1517 /* called holding qlock */
1518 static void process_single_up_tx_qlock(struct drm_dp_mst_topology_mgr *mgr,
1519 struct drm_dp_sideband_msg_tx *txmsg)
1520 {
1521 int ret;
1522
1523 /* construct a chunk from the first msg in the tx_msg queue */
1524 ret = process_single_tx_qlock(mgr, txmsg, true);
1525
1526 if (ret != 1)
1527 DRM_DEBUG_KMS("failed to send msg in q %d\n", ret);
1528
1529 txmsg->dst->tx_slots[txmsg->seqno] = NULL;
1530 }
1531
1532 static void drm_dp_queue_down_tx(struct drm_dp_mst_topology_mgr *mgr,
1533 struct drm_dp_sideband_msg_tx *txmsg)
1534 {
1535 mutex_lock(&mgr->qlock);
1536 list_add_tail(&txmsg->next, &mgr->tx_msg_downq);
1537 if (list_is_singular(&mgr->tx_msg_downq))
1538 process_single_down_tx_qlock(mgr);
1539 mutex_unlock(&mgr->qlock);
1540 }
1541
1542 static void drm_dp_send_link_address(struct drm_dp_mst_topology_mgr *mgr,
1543 struct drm_dp_mst_branch *mstb)
1544 {
1545 int len;
1546 struct drm_dp_sideband_msg_tx *txmsg;
1547 int ret;
1548
1549 txmsg = kzalloc(sizeof(*txmsg), GFP_KERNEL);
1550 if (!txmsg)
1551 return;
1552
1553 txmsg->dst = mstb;
1554 len = build_link_address(txmsg);
1555
1556 mstb->link_address_sent = true;
1557 drm_dp_queue_down_tx(mgr, txmsg);
1558
1559 ret = drm_dp_mst_wait_tx_reply(mstb, txmsg);
1560 if (ret > 0) {
1561 int i;
1562
1563 if (txmsg->reply.reply_type == 1)
1564 DRM_DEBUG_KMS("link address nak received\n");
1565 else {
1566 DRM_DEBUG_KMS("link address reply: %d\n", txmsg->reply.u.link_addr.nports);
1567 for (i = 0; i < txmsg->reply.u.link_addr.nports; i++) {
1568 DRM_DEBUG_KMS("port %d: input %d, pdt: %d, pn: %d, dpcd_rev: %02x, mcs: %d, ddps: %d, ldps %d, sdp %d/%d\n", i,
1569 txmsg->reply.u.link_addr.ports[i].input_port,
1570 txmsg->reply.u.link_addr.ports[i].peer_device_type,
1571 txmsg->reply.u.link_addr.ports[i].port_number,
1572 txmsg->reply.u.link_addr.ports[i].dpcd_revision,
1573 txmsg->reply.u.link_addr.ports[i].mcs,
1574 txmsg->reply.u.link_addr.ports[i].ddps,
1575 txmsg->reply.u.link_addr.ports[i].legacy_device_plug_status,
1576 txmsg->reply.u.link_addr.ports[i].num_sdp_streams,
1577 txmsg->reply.u.link_addr.ports[i].num_sdp_stream_sinks);
1578 }
1579
1580 drm_dp_check_mstb_guid(mstb, txmsg->reply.u.link_addr.guid);
1581
1582 for (i = 0; i < txmsg->reply.u.link_addr.nports; i++) {
1583 drm_dp_add_port(mstb, mgr->dev, &txmsg->reply.u.link_addr.ports[i]);
1584 }
1585 (*mgr->cbs->hotplug)(mgr);
1586 }
1587 } else {
1588 mstb->link_address_sent = false;
1589 DRM_DEBUG_KMS("link address failed %d\n", ret);
1590 }
1591
1592 kfree(txmsg);
1593 }
1594
1595 static int drm_dp_send_enum_path_resources(struct drm_dp_mst_topology_mgr *mgr,
1596 struct drm_dp_mst_branch *mstb,
1597 struct drm_dp_mst_port *port)
1598 {
1599 int len;
1600 struct drm_dp_sideband_msg_tx *txmsg;
1601 int ret;
1602
1603 txmsg = kzalloc(sizeof(*txmsg), GFP_KERNEL);
1604 if (!txmsg)
1605 return -ENOMEM;
1606
1607 txmsg->dst = mstb;
1608 len = build_enum_path_resources(txmsg, port->port_num);
1609
1610 drm_dp_queue_down_tx(mgr, txmsg);
1611
1612 ret = drm_dp_mst_wait_tx_reply(mstb, txmsg);
1613 if (ret > 0) {
1614 if (txmsg->reply.reply_type == 1)
1615 DRM_DEBUG_KMS("enum path resources nak received\n");
1616 else {
1617 if (port->port_num != txmsg->reply.u.path_resources.port_number)
1618 DRM_ERROR("got incorrect port in response\n");
1619 DRM_DEBUG_KMS("enum path resources %d: %d %d\n", txmsg->reply.u.path_resources.port_number, txmsg->reply.u.path_resources.full_payload_bw_number,
1620 txmsg->reply.u.path_resources.avail_payload_bw_number);
1621 port->available_pbn = txmsg->reply.u.path_resources.avail_payload_bw_number;
1622 }
1623 }
1624
1625 kfree(txmsg);
1626 return 0;
1627 }
1628
1629 static struct drm_dp_mst_port *drm_dp_get_last_connected_port_to_mstb(struct drm_dp_mst_branch *mstb)
1630 {
1631 if (!mstb->port_parent)
1632 return NULL;
1633
1634 if (mstb->port_parent->mstb != mstb)
1635 return mstb->port_parent;
1636
1637 return drm_dp_get_last_connected_port_to_mstb(mstb->port_parent->parent);
1638 }
1639
1640 static struct drm_dp_mst_branch *drm_dp_get_last_connected_port_and_mstb(struct drm_dp_mst_topology_mgr *mgr,
1641 struct drm_dp_mst_branch *mstb,
1642 int *port_num)
1643 {
1644 struct drm_dp_mst_branch *rmstb = NULL;
1645 struct drm_dp_mst_port *found_port;
1646 mutex_lock(&mgr->lock);
1647 if (mgr->mst_primary) {
1648 found_port = drm_dp_get_last_connected_port_to_mstb(mstb);
1649
1650 if (found_port) {
1651 rmstb = found_port->parent;
1652 kref_get(&rmstb->kref);
1653 *port_num = found_port->port_num;
1654 }
1655 }
1656 mutex_unlock(&mgr->lock);
1657 return rmstb;
1658 }
1659
1660 static int drm_dp_payload_send_msg(struct drm_dp_mst_topology_mgr *mgr,
1661 struct drm_dp_mst_port *port,
1662 int id,
1663 int pbn)
1664 {
1665 struct drm_dp_sideband_msg_tx *txmsg;
1666 struct drm_dp_mst_branch *mstb;
1667 int len, ret, port_num;
1668 u8 sinks[DRM_DP_MAX_SDP_STREAMS];
1669 int i;
1670
1671 port = drm_dp_get_validated_port_ref(mgr, port);
1672 if (!port)
1673 return -EINVAL;
1674
1675 port_num = port->port_num;
1676 mstb = drm_dp_get_validated_mstb_ref(mgr, port->parent);
1677 if (!mstb) {
1678 mstb = drm_dp_get_last_connected_port_and_mstb(mgr, port->parent, &port_num);
1679
1680 if (!mstb) {
1681 drm_dp_put_port(port);
1682 return -EINVAL;
1683 }
1684 }
1685
1686 txmsg = kzalloc(sizeof(*txmsg), GFP_KERNEL);
1687 if (!txmsg) {
1688 ret = -ENOMEM;
1689 goto fail_put;
1690 }
1691
1692 for (i = 0; i < port->num_sdp_streams; i++)
1693 sinks[i] = i;
1694
1695 txmsg->dst = mstb;
1696 len = build_allocate_payload(txmsg, port_num,
1697 id,
1698 pbn, port->num_sdp_streams, sinks);
1699
1700 drm_dp_queue_down_tx(mgr, txmsg);
1701
1702 ret = drm_dp_mst_wait_tx_reply(mstb, txmsg);
1703 if (ret > 0) {
1704 if (txmsg->reply.reply_type == 1) {
1705 ret = -EINVAL;
1706 } else
1707 ret = 0;
1708 }
1709 kfree(txmsg);
1710 fail_put:
1711 drm_dp_put_mst_branch_device(mstb);
1712 drm_dp_put_port(port);
1713 return ret;
1714 }
1715
1716 static int drm_dp_create_payload_step1(struct drm_dp_mst_topology_mgr *mgr,
1717 int id,
1718 struct drm_dp_payload *payload)
1719 {
1720 int ret;
1721
1722 ret = drm_dp_dpcd_write_payload(mgr, id, payload);
1723 if (ret < 0) {
1724 payload->payload_state = 0;
1725 return ret;
1726 }
1727 payload->payload_state = DP_PAYLOAD_LOCAL;
1728 return 0;
1729 }
1730
1731 static int drm_dp_create_payload_step2(struct drm_dp_mst_topology_mgr *mgr,
1732 struct drm_dp_mst_port *port,
1733 int id,
1734 struct drm_dp_payload *payload)
1735 {
1736 int ret;
1737 ret = drm_dp_payload_send_msg(mgr, port, id, port->vcpi.pbn);
1738 if (ret < 0)
1739 return ret;
1740 payload->payload_state = DP_PAYLOAD_REMOTE;
1741 return ret;
1742 }
1743
1744 static int drm_dp_destroy_payload_step1(struct drm_dp_mst_topology_mgr *mgr,
1745 struct drm_dp_mst_port *port,
1746 int id,
1747 struct drm_dp_payload *payload)
1748 {
1749 DRM_DEBUG_KMS("\n");
1750 /* its okay for these to fail */
1751 if (port) {
1752 drm_dp_payload_send_msg(mgr, port, id, 0);
1753 }
1754
1755 drm_dp_dpcd_write_payload(mgr, id, payload);
1756 payload->payload_state = DP_PAYLOAD_DELETE_LOCAL;
1757 return 0;
1758 }
1759
1760 static int drm_dp_destroy_payload_step2(struct drm_dp_mst_topology_mgr *mgr,
1761 int id,
1762 struct drm_dp_payload *payload)
1763 {
1764 payload->payload_state = 0;
1765 return 0;
1766 }
1767
1768 /**
1769 * drm_dp_update_payload_part1() - Execute payload update part 1
1770 * @mgr: manager to use.
1771 *
1772 * This iterates over all proposed virtual channels, and tries to
1773 * allocate space in the link for them. For 0->slots transitions,
1774 * this step just writes the VCPI to the MST device. For slots->0
1775 * transitions, this writes the updated VCPIs and removes the
1776 * remote VC payloads.
1777 *
1778 * after calling this the driver should generate ACT and payload
1779 * packets.
1780 */
1781 int drm_dp_update_payload_part1(struct drm_dp_mst_topology_mgr *mgr)
1782 {
1783 int i, j;
1784 int cur_slots = 1;
1785 struct drm_dp_payload req_payload;
1786 struct drm_dp_mst_port *port;
1787
1788 mutex_lock(&mgr->payload_lock);
1789 for (i = 0; i < mgr->max_payloads; i++) {
1790 /* solve the current payloads - compare to the hw ones
1791 - update the hw view */
1792 req_payload.start_slot = cur_slots;
1793 if (mgr->proposed_vcpis[i]) {
1794 port = container_of(mgr->proposed_vcpis[i], struct drm_dp_mst_port, vcpi);
1795 port = drm_dp_get_validated_port_ref(mgr, port);
1796 if (!port) {
1797 mutex_unlock(&mgr->payload_lock);
1798 return -EINVAL;
1799 }
1800 req_payload.num_slots = mgr->proposed_vcpis[i]->num_slots;
1801 req_payload.vcpi = mgr->proposed_vcpis[i]->vcpi;
1802 } else {
1803 port = NULL;
1804 req_payload.num_slots = 0;
1805 }
1806
1807 if (mgr->payloads[i].start_slot != req_payload.start_slot) {
1808 mgr->payloads[i].start_slot = req_payload.start_slot;
1809 }
1810 /* work out what is required to happen with this payload */
1811 if (mgr->payloads[i].num_slots != req_payload.num_slots) {
1812
1813 /* need to push an update for this payload */
1814 if (req_payload.num_slots) {
1815 drm_dp_create_payload_step1(mgr, mgr->proposed_vcpis[i]->vcpi, &req_payload);
1816 mgr->payloads[i].num_slots = req_payload.num_slots;
1817 mgr->payloads[i].vcpi = req_payload.vcpi;
1818 } else if (mgr->payloads[i].num_slots) {
1819 mgr->payloads[i].num_slots = 0;
1820 drm_dp_destroy_payload_step1(mgr, port, port->vcpi.vcpi, &mgr->payloads[i]);
1821 req_payload.payload_state = mgr->payloads[i].payload_state;
1822 mgr->payloads[i].start_slot = 0;
1823 }
1824 mgr->payloads[i].payload_state = req_payload.payload_state;
1825 }
1826 cur_slots += req_payload.num_slots;
1827
1828 if (port)
1829 drm_dp_put_port(port);
1830 }
1831
1832 for (i = 0; i < mgr->max_payloads; i++) {
1833 if (mgr->payloads[i].payload_state == DP_PAYLOAD_DELETE_LOCAL) {
1834 DRM_DEBUG_KMS("removing payload %d\n", i);
1835 for (j = i; j < mgr->max_payloads - 1; j++) {
1836 memcpy(&mgr->payloads[j], &mgr->payloads[j + 1], sizeof(struct drm_dp_payload));
1837 mgr->proposed_vcpis[j] = mgr->proposed_vcpis[j + 1];
1838 if (mgr->proposed_vcpis[j] && mgr->proposed_vcpis[j]->num_slots) {
1839 set_bit(j + 1, &mgr->payload_mask);
1840 } else {
1841 clear_bit(j + 1, &mgr->payload_mask);
1842 }
1843 }
1844 memset(&mgr->payloads[mgr->max_payloads - 1], 0, sizeof(struct drm_dp_payload));
1845 mgr->proposed_vcpis[mgr->max_payloads - 1] = NULL;
1846 clear_bit(mgr->max_payloads, &mgr->payload_mask);
1847
1848 }
1849 }
1850 mutex_unlock(&mgr->payload_lock);
1851
1852 return 0;
1853 }
1854 EXPORT_SYMBOL(drm_dp_update_payload_part1);
1855
1856 /**
1857 * drm_dp_update_payload_part2() - Execute payload update part 2
1858 * @mgr: manager to use.
1859 *
1860 * This iterates over all proposed virtual channels, and tries to
1861 * allocate space in the link for them. For 0->slots transitions,
1862 * this step writes the remote VC payload commands. For slots->0
1863 * this just resets some internal state.
1864 */
1865 int drm_dp_update_payload_part2(struct drm_dp_mst_topology_mgr *mgr)
1866 {
1867 struct drm_dp_mst_port *port;
1868 int i;
1869 int ret = 0;
1870 mutex_lock(&mgr->payload_lock);
1871 for (i = 0; i < mgr->max_payloads; i++) {
1872
1873 if (!mgr->proposed_vcpis[i])
1874 continue;
1875
1876 port = container_of(mgr->proposed_vcpis[i], struct drm_dp_mst_port, vcpi);
1877
1878 DRM_DEBUG_KMS("payload %d %d\n", i, mgr->payloads[i].payload_state);
1879 if (mgr->payloads[i].payload_state == DP_PAYLOAD_LOCAL) {
1880 ret = drm_dp_create_payload_step2(mgr, port, mgr->proposed_vcpis[i]->vcpi, &mgr->payloads[i]);
1881 } else if (mgr->payloads[i].payload_state == DP_PAYLOAD_DELETE_LOCAL) {
1882 ret = drm_dp_destroy_payload_step2(mgr, mgr->proposed_vcpis[i]->vcpi, &mgr->payloads[i]);
1883 }
1884 if (ret) {
1885 mutex_unlock(&mgr->payload_lock);
1886 return ret;
1887 }
1888 }
1889 mutex_unlock(&mgr->payload_lock);
1890 return 0;
1891 }
1892 EXPORT_SYMBOL(drm_dp_update_payload_part2);
1893
1894 #if 0 /* unused as of yet */
1895 static int drm_dp_send_dpcd_read(struct drm_dp_mst_topology_mgr *mgr,
1896 struct drm_dp_mst_port *port,
1897 int offset, int size)
1898 {
1899 int len;
1900 struct drm_dp_sideband_msg_tx *txmsg;
1901
1902 txmsg = kzalloc(sizeof(*txmsg), GFP_KERNEL);
1903 if (!txmsg)
1904 return -ENOMEM;
1905
1906 len = build_dpcd_read(txmsg, port->port_num, 0, 8);
1907 txmsg->dst = port->parent;
1908
1909 drm_dp_queue_down_tx(mgr, txmsg);
1910
1911 return 0;
1912 }
1913 #endif
1914
1915 static int drm_dp_send_dpcd_write(struct drm_dp_mst_topology_mgr *mgr,
1916 struct drm_dp_mst_port *port,
1917 int offset, int size, u8 *bytes)
1918 {
1919 int len;
1920 int ret;
1921 struct drm_dp_sideband_msg_tx *txmsg;
1922 struct drm_dp_mst_branch *mstb;
1923
1924 mstb = drm_dp_get_validated_mstb_ref(mgr, port->parent);
1925 if (!mstb)
1926 return -EINVAL;
1927
1928 txmsg = kzalloc(sizeof(*txmsg), GFP_KERNEL);
1929 if (!txmsg) {
1930 ret = -ENOMEM;
1931 goto fail_put;
1932 }
1933
1934 len = build_dpcd_write(txmsg, port->port_num, offset, size, bytes);
1935 txmsg->dst = mstb;
1936
1937 drm_dp_queue_down_tx(mgr, txmsg);
1938
1939 ret = drm_dp_mst_wait_tx_reply(mstb, txmsg);
1940 if (ret > 0) {
1941 if (txmsg->reply.reply_type == 1) {
1942 ret = -EINVAL;
1943 } else
1944 ret = 0;
1945 }
1946 kfree(txmsg);
1947 fail_put:
1948 drm_dp_put_mst_branch_device(mstb);
1949 return ret;
1950 }
1951
1952 static int drm_dp_encode_up_ack_reply(struct drm_dp_sideband_msg_tx *msg, u8 req_type)
1953 {
1954 struct drm_dp_sideband_msg_reply_body reply;
1955
1956 reply.reply_type = 0;
1957 reply.req_type = req_type;
1958 drm_dp_encode_sideband_reply(&reply, msg);
1959 return 0;
1960 }
1961
1962 static int drm_dp_send_up_ack_reply(struct drm_dp_mst_topology_mgr *mgr,
1963 struct drm_dp_mst_branch *mstb,
1964 int req_type, int seqno, bool broadcast)
1965 {
1966 struct drm_dp_sideband_msg_tx *txmsg;
1967
1968 txmsg = kzalloc(sizeof(*txmsg), GFP_KERNEL);
1969 if (!txmsg)
1970 return -ENOMEM;
1971
1972 txmsg->dst = mstb;
1973 txmsg->seqno = seqno;
1974 drm_dp_encode_up_ack_reply(txmsg, req_type);
1975
1976 mutex_lock(&mgr->qlock);
1977
1978 process_single_up_tx_qlock(mgr, txmsg);
1979
1980 mutex_unlock(&mgr->qlock);
1981
1982 kfree(txmsg);
1983 return 0;
1984 }
1985
1986 static bool drm_dp_get_vc_payload_bw(int dp_link_bw,
1987 int dp_link_count,
1988 int *out)
1989 {
1990 switch (dp_link_bw) {
1991 default:
1992 DRM_DEBUG_KMS("invalid link bandwidth in DPCD: %x (link count: %d)\n",
1993 dp_link_bw, dp_link_count);
1994 return false;
1995
1996 case DP_LINK_BW_1_62:
1997 *out = 3 * dp_link_count;
1998 break;
1999 case DP_LINK_BW_2_7:
2000 *out = 5 * dp_link_count;
2001 break;
2002 case DP_LINK_BW_5_4:
2003 *out = 10 * dp_link_count;
2004 break;
2005 }
2006 return true;
2007 }
2008
2009 /**
2010 * drm_dp_mst_topology_mgr_set_mst() - Set the MST state for a topology manager
2011 * @mgr: manager to set state for
2012 * @mst_state: true to enable MST on this connector - false to disable.
2013 *
2014 * This is called by the driver when it detects an MST capable device plugged
2015 * into a DP MST capable port, or when a DP MST capable device is unplugged.
2016 */
2017 int drm_dp_mst_topology_mgr_set_mst(struct drm_dp_mst_topology_mgr *mgr, bool mst_state)
2018 {
2019 int ret = 0;
2020 struct drm_dp_mst_branch *mstb = NULL;
2021
2022 mutex_lock(&mgr->lock);
2023 if (mst_state == mgr->mst_state)
2024 goto out_unlock;
2025
2026 mgr->mst_state = mst_state;
2027 /* set the device into MST mode */
2028 if (mst_state) {
2029 WARN_ON(mgr->mst_primary);
2030
2031 /* get dpcd info */
2032 ret = drm_dp_dpcd_read(mgr->aux, DP_DPCD_REV, mgr->dpcd, DP_RECEIVER_CAP_SIZE);
2033 if (ret != DP_RECEIVER_CAP_SIZE) {
2034 DRM_DEBUG_KMS("failed to read DPCD\n");
2035 goto out_unlock;
2036 }
2037
2038 if (!drm_dp_get_vc_payload_bw(mgr->dpcd[1],
2039 mgr->dpcd[2] & DP_MAX_LANE_COUNT_MASK,
2040 &mgr->pbn_div)) {
2041 ret = -EINVAL;
2042 goto out_unlock;
2043 }
2044
2045 mgr->total_pbn = 2560;
2046 mgr->total_slots = DIV_ROUND_UP(mgr->total_pbn, mgr->pbn_div);
2047 mgr->avail_slots = mgr->total_slots;
2048
2049 /* add initial branch device at LCT 1 */
2050 mstb = drm_dp_add_mst_branch_device(1, NULL);
2051 if (mstb == NULL) {
2052 ret = -ENOMEM;
2053 goto out_unlock;
2054 }
2055 mstb->mgr = mgr;
2056
2057 /* give this the main reference */
2058 mgr->mst_primary = mstb;
2059 kref_get(&mgr->mst_primary->kref);
2060
2061 ret = drm_dp_dpcd_writeb(mgr->aux, DP_MSTM_CTRL,
2062 DP_MST_EN | DP_UP_REQ_EN | DP_UPSTREAM_IS_SRC);
2063 if (ret < 0) {
2064 goto out_unlock;
2065 }
2066
2067 {
2068 struct drm_dp_payload reset_pay;
2069 reset_pay.start_slot = 0;
2070 reset_pay.num_slots = 0x3f;
2071 drm_dp_dpcd_write_payload(mgr, 0, &reset_pay);
2072 }
2073
2074 queue_work(system_long_wq, &mgr->work);
2075
2076 ret = 0;
2077 } else {
2078 /* disable MST on the device */
2079 mstb = mgr->mst_primary;
2080 mgr->mst_primary = NULL;
2081 /* this can fail if the device is gone */
2082 drm_dp_dpcd_writeb(mgr->aux, DP_MSTM_CTRL, 0);
2083 ret = 0;
2084 memset(mgr->payloads, 0, mgr->max_payloads * sizeof(struct drm_dp_payload));
2085 mgr->payload_mask = 0;
2086 set_bit(0, &mgr->payload_mask);
2087 mgr->vcpi_mask = 0;
2088 }
2089
2090 out_unlock:
2091 mutex_unlock(&mgr->lock);
2092 if (mstb)
2093 drm_dp_put_mst_branch_device(mstb);
2094 return ret;
2095
2096 }
2097 EXPORT_SYMBOL(drm_dp_mst_topology_mgr_set_mst);
2098
2099 /**
2100 * drm_dp_mst_topology_mgr_suspend() - suspend the MST manager
2101 * @mgr: manager to suspend
2102 *
2103 * This function tells the MST device that we can't handle UP messages
2104 * anymore. This should stop it from sending any since we are suspended.
2105 */
2106 void drm_dp_mst_topology_mgr_suspend(struct drm_dp_mst_topology_mgr *mgr)
2107 {
2108 mutex_lock(&mgr->lock);
2109 drm_dp_dpcd_writeb(mgr->aux, DP_MSTM_CTRL,
2110 DP_MST_EN | DP_UPSTREAM_IS_SRC);
2111 mutex_unlock(&mgr->lock);
2112 flush_work(&mgr->work);
2113 flush_work(&mgr->destroy_connector_work);
2114 }
2115 EXPORT_SYMBOL(drm_dp_mst_topology_mgr_suspend);
2116
2117 /**
2118 * drm_dp_mst_topology_mgr_resume() - resume the MST manager
2119 * @mgr: manager to resume
2120 *
2121 * This will fetch DPCD and see if the device is still there,
2122 * if it is, it will rewrite the MSTM control bits, and return.
2123 *
2124 * if the device fails this returns -1, and the driver should do
2125 * a full MST reprobe, in case we were undocked.
2126 */
2127 int drm_dp_mst_topology_mgr_resume(struct drm_dp_mst_topology_mgr *mgr)
2128 {
2129 int ret = 0;
2130
2131 mutex_lock(&mgr->lock);
2132
2133 if (mgr->mst_primary) {
2134 int sret;
2135 u8 guid[16];
2136
2137 sret = drm_dp_dpcd_read(mgr->aux, DP_DPCD_REV, mgr->dpcd, DP_RECEIVER_CAP_SIZE);
2138 if (sret != DP_RECEIVER_CAP_SIZE) {
2139 DRM_DEBUG_KMS("dpcd read failed - undocked during suspend?\n");
2140 ret = -1;
2141 goto out_unlock;
2142 }
2143
2144 ret = drm_dp_dpcd_writeb(mgr->aux, DP_MSTM_CTRL,
2145 DP_MST_EN | DP_UP_REQ_EN | DP_UPSTREAM_IS_SRC);
2146 if (ret < 0) {
2147 DRM_DEBUG_KMS("mst write failed - undocked during suspend?\n");
2148 ret = -1;
2149 goto out_unlock;
2150 }
2151
2152 /* Some hubs forget their guids after they resume */
2153 sret = drm_dp_dpcd_read(mgr->aux, DP_GUID, guid, 16);
2154 if (sret != 16) {
2155 DRM_DEBUG_KMS("dpcd read failed - undocked during suspend?\n");
2156 ret = -1;
2157 goto out_unlock;
2158 }
2159 drm_dp_check_mstb_guid(mgr->mst_primary, guid);
2160
2161 ret = 0;
2162 } else
2163 ret = -1;
2164
2165 out_unlock:
2166 mutex_unlock(&mgr->lock);
2167 return ret;
2168 }
2169 EXPORT_SYMBOL(drm_dp_mst_topology_mgr_resume);
2170
2171 static void drm_dp_get_one_sb_msg(struct drm_dp_mst_topology_mgr *mgr, bool up)
2172 {
2173 int len;
2174 u8 replyblock[32];
2175 int replylen, origlen, curreply;
2176 int ret;
2177 struct drm_dp_sideband_msg_rx *msg;
2178 int basereg = up ? DP_SIDEBAND_MSG_UP_REQ_BASE : DP_SIDEBAND_MSG_DOWN_REP_BASE;
2179 msg = up ? &mgr->up_req_recv : &mgr->down_rep_recv;
2180
2181 len = min(mgr->max_dpcd_transaction_bytes, 16);
2182 ret = drm_dp_dpcd_read(mgr->aux, basereg,
2183 replyblock, len);
2184 if (ret != len) {
2185 DRM_DEBUG_KMS("failed to read DPCD down rep %d %d\n", len, ret);
2186 return;
2187 }
2188 ret = drm_dp_sideband_msg_build(msg, replyblock, len, true);
2189 if (!ret) {
2190 DRM_DEBUG_KMS("sideband msg build failed %d\n", replyblock[0]);
2191 return;
2192 }
2193 replylen = msg->curchunk_len + msg->curchunk_hdrlen;
2194
2195 origlen = replylen;
2196 replylen -= len;
2197 curreply = len;
2198 while (replylen > 0) {
2199 len = min3(replylen, mgr->max_dpcd_transaction_bytes, 16);
2200 ret = drm_dp_dpcd_read(mgr->aux, basereg + curreply,
2201 replyblock, len);
2202 if (ret != len) {
2203 DRM_DEBUG_KMS("failed to read a chunk\n");
2204 }
2205 ret = drm_dp_sideband_msg_build(msg, replyblock, len, false);
2206 if (ret == false)
2207 DRM_DEBUG_KMS("failed to build sideband msg\n");
2208 curreply += len;
2209 replylen -= len;
2210 }
2211 }
2212
2213 static int drm_dp_mst_handle_down_rep(struct drm_dp_mst_topology_mgr *mgr)
2214 {
2215 int ret = 0;
2216
2217 drm_dp_get_one_sb_msg(mgr, false);
2218
2219 if (mgr->down_rep_recv.have_eomt) {
2220 struct drm_dp_sideband_msg_tx *txmsg;
2221 struct drm_dp_mst_branch *mstb;
2222 int slot = -1;
2223 mstb = drm_dp_get_mst_branch_device(mgr,
2224 mgr->down_rep_recv.initial_hdr.lct,
2225 mgr->down_rep_recv.initial_hdr.rad);
2226
2227 if (!mstb) {
2228 DRM_DEBUG_KMS("Got MST reply from unknown device %d\n", mgr->down_rep_recv.initial_hdr.lct);
2229 memset(&mgr->down_rep_recv, 0, sizeof(struct drm_dp_sideband_msg_rx));
2230 return 0;
2231 }
2232
2233 /* find the message */
2234 slot = mgr->down_rep_recv.initial_hdr.seqno;
2235 mutex_lock(&mgr->qlock);
2236 txmsg = mstb->tx_slots[slot];
2237 /* remove from slots */
2238 mutex_unlock(&mgr->qlock);
2239
2240 if (!txmsg) {
2241 DRM_DEBUG_KMS("Got MST reply with no msg %p %d %d %02x %02x\n",
2242 mstb,
2243 mgr->down_rep_recv.initial_hdr.seqno,
2244 mgr->down_rep_recv.initial_hdr.lct,
2245 mgr->down_rep_recv.initial_hdr.rad[0],
2246 mgr->down_rep_recv.msg[0]);
2247 drm_dp_put_mst_branch_device(mstb);
2248 memset(&mgr->down_rep_recv, 0, sizeof(struct drm_dp_sideband_msg_rx));
2249 return 0;
2250 }
2251
2252 drm_dp_sideband_parse_reply(&mgr->down_rep_recv, &txmsg->reply);
2253 if (txmsg->reply.reply_type == 1) {
2254 DRM_DEBUG_KMS("Got NAK reply: req 0x%02x, reason 0x%02x, nak data 0x%02x\n", txmsg->reply.req_type, txmsg->reply.u.nak.reason, txmsg->reply.u.nak.nak_data);
2255 }
2256
2257 memset(&mgr->down_rep_recv, 0, sizeof(struct drm_dp_sideband_msg_rx));
2258 drm_dp_put_mst_branch_device(mstb);
2259
2260 mutex_lock(&mgr->qlock);
2261 txmsg->state = DRM_DP_SIDEBAND_TX_RX;
2262 mstb->tx_slots[slot] = NULL;
2263 mutex_unlock(&mgr->qlock);
2264
2265 wake_up(&mgr->tx_waitq);
2266 }
2267 return ret;
2268 }
2269
2270 static int drm_dp_mst_handle_up_req(struct drm_dp_mst_topology_mgr *mgr)
2271 {
2272 int ret = 0;
2273 drm_dp_get_one_sb_msg(mgr, true);
2274
2275 if (mgr->up_req_recv.have_eomt) {
2276 struct drm_dp_sideband_msg_req_body msg;
2277 struct drm_dp_mst_branch *mstb = NULL;
2278 bool seqno;
2279
2280 if (!mgr->up_req_recv.initial_hdr.broadcast) {
2281 mstb = drm_dp_get_mst_branch_device(mgr,
2282 mgr->up_req_recv.initial_hdr.lct,
2283 mgr->up_req_recv.initial_hdr.rad);
2284 if (!mstb) {
2285 DRM_DEBUG_KMS("Got MST reply from unknown device %d\n", mgr->up_req_recv.initial_hdr.lct);
2286 memset(&mgr->up_req_recv, 0, sizeof(struct drm_dp_sideband_msg_rx));
2287 return 0;
2288 }
2289 }
2290
2291 seqno = mgr->up_req_recv.initial_hdr.seqno;
2292 drm_dp_sideband_parse_req(&mgr->up_req_recv, &msg);
2293
2294 if (msg.req_type == DP_CONNECTION_STATUS_NOTIFY) {
2295 drm_dp_send_up_ack_reply(mgr, mgr->mst_primary, msg.req_type, seqno, false);
2296
2297 if (!mstb)
2298 mstb = drm_dp_get_mst_branch_device_by_guid(mgr, msg.u.conn_stat.guid);
2299
2300 if (!mstb) {
2301 DRM_DEBUG_KMS("Got MST reply from unknown device %d\n", mgr->up_req_recv.initial_hdr.lct);
2302 memset(&mgr->up_req_recv, 0, sizeof(struct drm_dp_sideband_msg_rx));
2303 return 0;
2304 }
2305
2306 drm_dp_update_port(mstb, &msg.u.conn_stat);
2307
2308 DRM_DEBUG_KMS("Got CSN: pn: %d ldps:%d ddps: %d mcs: %d ip: %d pdt: %d\n", msg.u.conn_stat.port_number, msg.u.conn_stat.legacy_device_plug_status, msg.u.conn_stat.displayport_device_plug_status, msg.u.conn_stat.message_capability_status, msg.u.conn_stat.input_port, msg.u.conn_stat.peer_device_type);
2309 (*mgr->cbs->hotplug)(mgr);
2310
2311 } else if (msg.req_type == DP_RESOURCE_STATUS_NOTIFY) {
2312 drm_dp_send_up_ack_reply(mgr, mgr->mst_primary, msg.req_type, seqno, false);
2313 if (!mstb)
2314 mstb = drm_dp_get_mst_branch_device_by_guid(mgr, msg.u.resource_stat.guid);
2315
2316 if (!mstb) {
2317 DRM_DEBUG_KMS("Got MST reply from unknown device %d\n", mgr->up_req_recv.initial_hdr.lct);
2318 memset(&mgr->up_req_recv, 0, sizeof(struct drm_dp_sideband_msg_rx));
2319 return 0;
2320 }
2321
2322 DRM_DEBUG_KMS("Got RSN: pn: %d avail_pbn %d\n", msg.u.resource_stat.port_number, msg.u.resource_stat.available_pbn);
2323 }
2324
2325 drm_dp_put_mst_branch_device(mstb);
2326 memset(&mgr->up_req_recv, 0, sizeof(struct drm_dp_sideband_msg_rx));
2327 }
2328 return ret;
2329 }
2330
2331 /**
2332 * drm_dp_mst_hpd_irq() - MST hotplug IRQ notify
2333 * @mgr: manager to notify irq for.
2334 * @esi: 4 bytes from SINK_COUNT_ESI
2335 * @handled: whether the hpd interrupt was consumed or not
2336 *
2337 * This should be called from the driver when it detects a short IRQ,
2338 * along with the value of the DEVICE_SERVICE_IRQ_VECTOR_ESI0. The
2339 * topology manager will process the sideband messages received as a result
2340 * of this.
2341 */
2342 int drm_dp_mst_hpd_irq(struct drm_dp_mst_topology_mgr *mgr, u8 *esi, bool *handled)
2343 {
2344 int ret = 0;
2345 int sc;
2346 *handled = false;
2347 sc = esi[0] & 0x3f;
2348
2349 if (sc != mgr->sink_count) {
2350 mgr->sink_count = sc;
2351 *handled = true;
2352 }
2353
2354 if (esi[1] & DP_DOWN_REP_MSG_RDY) {
2355 ret = drm_dp_mst_handle_down_rep(mgr);
2356 *handled = true;
2357 }
2358
2359 if (esi[1] & DP_UP_REQ_MSG_RDY) {
2360 ret |= drm_dp_mst_handle_up_req(mgr);
2361 *handled = true;
2362 }
2363
2364 drm_dp_mst_kick_tx(mgr);
2365 return ret;
2366 }
2367 EXPORT_SYMBOL(drm_dp_mst_hpd_irq);
2368
2369 /**
2370 * drm_dp_mst_detect_port() - get connection status for an MST port
2371 * @connector: DRM connector for this port
2372 * @mgr: manager for this port
2373 * @port: unverified pointer to a port
2374 *
2375 * This returns the current connection state for a port. It validates the
2376 * port pointer still exists so the caller doesn't require a reference
2377 */
2378 enum drm_connector_status drm_dp_mst_detect_port(struct drm_connector *connector,
2379 struct drm_dp_mst_topology_mgr *mgr, struct drm_dp_mst_port *port)
2380 {
2381 enum drm_connector_status status = connector_status_disconnected;
2382
2383 /* we need to search for the port in the mgr in case its gone */
2384 port = drm_dp_get_validated_port_ref(mgr, port);
2385 if (!port)
2386 return connector_status_disconnected;
2387
2388 if (!port->ddps)
2389 goto out;
2390
2391 switch (port->pdt) {
2392 case DP_PEER_DEVICE_NONE:
2393 case DP_PEER_DEVICE_MST_BRANCHING:
2394 break;
2395
2396 case DP_PEER_DEVICE_SST_SINK:
2397 status = connector_status_connected;
2398 /* for logical ports - cache the EDID */
2399 if (port->port_num >= 8 && !port->cached_edid) {
2400 port->cached_edid = drm_get_edid(connector, &port->aux.ddc);
2401 }
2402 break;
2403 case DP_PEER_DEVICE_DP_LEGACY_CONV:
2404 if (port->ldps)
2405 status = connector_status_connected;
2406 break;
2407 }
2408 out:
2409 drm_dp_put_port(port);
2410 return status;
2411 }
2412 EXPORT_SYMBOL(drm_dp_mst_detect_port);
2413
2414 /**
2415 * drm_dp_mst_port_has_audio() - Check whether port has audio capability or not
2416 * @mgr: manager for this port
2417 * @port: unverified pointer to a port.
2418 *
2419 * This returns whether the port supports audio or not.
2420 */
2421 bool drm_dp_mst_port_has_audio(struct drm_dp_mst_topology_mgr *mgr,
2422 struct drm_dp_mst_port *port)
2423 {
2424 bool ret = false;
2425
2426 port = drm_dp_get_validated_port_ref(mgr, port);
2427 if (!port)
2428 return ret;
2429 ret = port->has_audio;
2430 drm_dp_put_port(port);
2431 return ret;
2432 }
2433 EXPORT_SYMBOL(drm_dp_mst_port_has_audio);
2434
2435 /**
2436 * drm_dp_mst_get_edid() - get EDID for an MST port
2437 * @connector: toplevel connector to get EDID for
2438 * @mgr: manager for this port
2439 * @port: unverified pointer to a port.
2440 *
2441 * This returns an EDID for the port connected to a connector,
2442 * It validates the pointer still exists so the caller doesn't require a
2443 * reference.
2444 */
2445 struct edid *drm_dp_mst_get_edid(struct drm_connector *connector, struct drm_dp_mst_topology_mgr *mgr, struct drm_dp_mst_port *port)
2446 {
2447 struct edid *edid = NULL;
2448
2449 /* we need to search for the port in the mgr in case its gone */
2450 port = drm_dp_get_validated_port_ref(mgr, port);
2451 if (!port)
2452 return NULL;
2453
2454 if (port->cached_edid)
2455 edid = drm_edid_duplicate(port->cached_edid);
2456 else {
2457 edid = drm_get_edid(connector, &port->aux.ddc);
2458 drm_mode_connector_set_tile_property(connector);
2459 }
2460 port->has_audio = drm_detect_monitor_audio(edid);
2461 drm_dp_put_port(port);
2462 return edid;
2463 }
2464 EXPORT_SYMBOL(drm_dp_mst_get_edid);
2465
2466 /**
2467 * drm_dp_find_vcpi_slots() - find slots for this PBN value
2468 * @mgr: manager to use
2469 * @pbn: payload bandwidth to convert into slots.
2470 */
2471 int drm_dp_find_vcpi_slots(struct drm_dp_mst_topology_mgr *mgr,
2472 int pbn)
2473 {
2474 int num_slots;
2475
2476 num_slots = DIV_ROUND_UP(pbn, mgr->pbn_div);
2477
2478 if (num_slots > mgr->avail_slots)
2479 return -ENOSPC;
2480 return num_slots;
2481 }
2482 EXPORT_SYMBOL(drm_dp_find_vcpi_slots);
2483
2484 static int drm_dp_init_vcpi(struct drm_dp_mst_topology_mgr *mgr,
2485 struct drm_dp_vcpi *vcpi, int pbn)
2486 {
2487 int num_slots;
2488 int ret;
2489
2490 num_slots = DIV_ROUND_UP(pbn, mgr->pbn_div);
2491
2492 if (num_slots > mgr->avail_slots)
2493 return -ENOSPC;
2494
2495 vcpi->pbn = pbn;
2496 vcpi->aligned_pbn = num_slots * mgr->pbn_div;
2497 vcpi->num_slots = num_slots;
2498
2499 ret = drm_dp_mst_assign_payload_id(mgr, vcpi);
2500 if (ret < 0)
2501 return ret;
2502 return 0;
2503 }
2504
2505 /**
2506 * drm_dp_mst_allocate_vcpi() - Allocate a virtual channel
2507 * @mgr: manager for this port
2508 * @port: port to allocate a virtual channel for.
2509 * @pbn: payload bandwidth number to request
2510 * @slots: returned number of slots for this PBN.
2511 */
2512 bool drm_dp_mst_allocate_vcpi(struct drm_dp_mst_topology_mgr *mgr, struct drm_dp_mst_port *port, int pbn, int *slots)
2513 {
2514 int ret;
2515
2516 port = drm_dp_get_validated_port_ref(mgr, port);
2517 if (!port)
2518 return false;
2519
2520 if (port->vcpi.vcpi > 0) {
2521 DRM_DEBUG_KMS("payload: vcpi %d already allocated for pbn %d - requested pbn %d\n", port->vcpi.vcpi, port->vcpi.pbn, pbn);
2522 if (pbn == port->vcpi.pbn) {
2523 *slots = port->vcpi.num_slots;
2524 drm_dp_put_port(port);
2525 return true;
2526 }
2527 }
2528
2529 ret = drm_dp_init_vcpi(mgr, &port->vcpi, pbn);
2530 if (ret) {
2531 DRM_DEBUG_KMS("failed to init vcpi %d %d %d\n", DIV_ROUND_UP(pbn, mgr->pbn_div), mgr->avail_slots, ret);
2532 goto out;
2533 }
2534 DRM_DEBUG_KMS("initing vcpi for %d %d\n", pbn, port->vcpi.num_slots);
2535 *slots = port->vcpi.num_slots;
2536
2537 drm_dp_put_port(port);
2538 return true;
2539 out:
2540 return false;
2541 }
2542 EXPORT_SYMBOL(drm_dp_mst_allocate_vcpi);
2543
2544 int drm_dp_mst_get_vcpi_slots(struct drm_dp_mst_topology_mgr *mgr, struct drm_dp_mst_port *port)
2545 {
2546 int slots = 0;
2547 port = drm_dp_get_validated_port_ref(mgr, port);
2548 if (!port)
2549 return slots;
2550
2551 slots = port->vcpi.num_slots;
2552 drm_dp_put_port(port);
2553 return slots;
2554 }
2555 EXPORT_SYMBOL(drm_dp_mst_get_vcpi_slots);
2556
2557 /**
2558 * drm_dp_mst_reset_vcpi_slots() - Reset number of slots to 0 for VCPI
2559 * @mgr: manager for this port
2560 * @port: unverified pointer to a port.
2561 *
2562 * This just resets the number of slots for the ports VCPI for later programming.
2563 */
2564 void drm_dp_mst_reset_vcpi_slots(struct drm_dp_mst_topology_mgr *mgr, struct drm_dp_mst_port *port)
2565 {
2566 port = drm_dp_get_validated_port_ref(mgr, port);
2567 if (!port)
2568 return;
2569 port->vcpi.num_slots = 0;
2570 drm_dp_put_port(port);
2571 }
2572 EXPORT_SYMBOL(drm_dp_mst_reset_vcpi_slots);
2573
2574 /**
2575 * drm_dp_mst_deallocate_vcpi() - deallocate a VCPI
2576 * @mgr: manager for this port
2577 * @port: unverified port to deallocate vcpi for
2578 */
2579 void drm_dp_mst_deallocate_vcpi(struct drm_dp_mst_topology_mgr *mgr, struct drm_dp_mst_port *port)
2580 {
2581 port = drm_dp_get_validated_port_ref(mgr, port);
2582 if (!port)
2583 return;
2584
2585 drm_dp_mst_put_payload_id(mgr, port->vcpi.vcpi);
2586 port->vcpi.num_slots = 0;
2587 port->vcpi.pbn = 0;
2588 port->vcpi.aligned_pbn = 0;
2589 port->vcpi.vcpi = 0;
2590 drm_dp_put_port(port);
2591 }
2592 EXPORT_SYMBOL(drm_dp_mst_deallocate_vcpi);
2593
2594 static int drm_dp_dpcd_write_payload(struct drm_dp_mst_topology_mgr *mgr,
2595 int id, struct drm_dp_payload *payload)
2596 {
2597 u8 payload_alloc[3], status;
2598 int ret;
2599 int retries = 0;
2600
2601 drm_dp_dpcd_writeb(mgr->aux, DP_PAYLOAD_TABLE_UPDATE_STATUS,
2602 DP_PAYLOAD_TABLE_UPDATED);
2603
2604 payload_alloc[0] = id;
2605 payload_alloc[1] = payload->start_slot;
2606 payload_alloc[2] = payload->num_slots;
2607
2608 ret = drm_dp_dpcd_write(mgr->aux, DP_PAYLOAD_ALLOCATE_SET, payload_alloc, 3);
2609 if (ret != 3) {
2610 DRM_DEBUG_KMS("failed to write payload allocation %d\n", ret);
2611 goto fail;
2612 }
2613
2614 retry:
2615 ret = drm_dp_dpcd_readb(mgr->aux, DP_PAYLOAD_TABLE_UPDATE_STATUS, &status);
2616 if (ret < 0) {
2617 DRM_DEBUG_KMS("failed to read payload table status %d\n", ret);
2618 goto fail;
2619 }
2620
2621 if (!(status & DP_PAYLOAD_TABLE_UPDATED)) {
2622 retries++;
2623 if (retries < 20) {
2624 usleep_range(10000, 20000);
2625 goto retry;
2626 }
2627 DRM_DEBUG_KMS("status not set after read payload table status %d\n", status);
2628 ret = -EINVAL;
2629 goto fail;
2630 }
2631 ret = 0;
2632 fail:
2633 return ret;
2634 }
2635
2636
2637 /**
2638 * drm_dp_check_act_status() - Check ACT handled status.
2639 * @mgr: manager to use
2640 *
2641 * Check the payload status bits in the DPCD for ACT handled completion.
2642 */
2643 int drm_dp_check_act_status(struct drm_dp_mst_topology_mgr *mgr)
2644 {
2645 u8 status;
2646 int ret;
2647 int count = 0;
2648
2649 do {
2650 ret = drm_dp_dpcd_readb(mgr->aux, DP_PAYLOAD_TABLE_UPDATE_STATUS, &status);
2651
2652 if (ret < 0) {
2653 DRM_DEBUG_KMS("failed to read payload table status %d\n", ret);
2654 goto fail;
2655 }
2656
2657 if (status & DP_PAYLOAD_ACT_HANDLED)
2658 break;
2659 count++;
2660 udelay(100);
2661
2662 } while (count < 30);
2663
2664 if (!(status & DP_PAYLOAD_ACT_HANDLED)) {
2665 DRM_DEBUG_KMS("failed to get ACT bit %d after %d retries\n", status, count);
2666 ret = -EINVAL;
2667 goto fail;
2668 }
2669 return 0;
2670 fail:
2671 return ret;
2672 }
2673 EXPORT_SYMBOL(drm_dp_check_act_status);
2674
2675 /**
2676 * drm_dp_calc_pbn_mode() - Calculate the PBN for a mode.
2677 * @clock: dot clock for the mode
2678 * @bpp: bpp for the mode.
2679 *
2680 * This uses the formula in the spec to calculate the PBN value for a mode.
2681 */
2682 int drm_dp_calc_pbn_mode(int clock, int bpp)
2683 {
2684 u64 kbps;
2685 s64 peak_kbps;
2686 u32 numerator;
2687 u32 denominator;
2688
2689 kbps = clock * bpp;
2690
2691 /*
2692 * margin 5300ppm + 300ppm ~ 0.6% as per spec, factor is 1.006
2693 * The unit of 54/64Mbytes/sec is an arbitrary unit chosen based on
2694 * common multiplier to render an integer PBN for all link rate/lane
2695 * counts combinations
2696 * calculate
2697 * peak_kbps *= (1006/1000)
2698 * peak_kbps *= (64/54)
2699 * peak_kbps *= 8 convert to bytes
2700 */
2701
2702 numerator = 64 * 1006;
2703 denominator = 54 * 8 * 1000 * 1000;
2704
2705 kbps *= numerator;
2706 peak_kbps = drm_fixp_from_fraction(kbps, denominator);
2707
2708 return drm_fixp2int_ceil(peak_kbps);
2709 }
2710 EXPORT_SYMBOL(drm_dp_calc_pbn_mode);
2711
2712 static int test_calc_pbn_mode(void)
2713 {
2714 int ret;
2715 ret = drm_dp_calc_pbn_mode(154000, 30);
2716 if (ret != 689) {
2717 DRM_ERROR("PBN calculation test failed - clock %d, bpp %d, expected PBN %d, actual PBN %d.\n",
2718 154000, 30, 689, ret);
2719 return -EINVAL;
2720 }
2721 ret = drm_dp_calc_pbn_mode(234000, 30);
2722 if (ret != 1047) {
2723 DRM_ERROR("PBN calculation test failed - clock %d, bpp %d, expected PBN %d, actual PBN %d.\n",
2724 234000, 30, 1047, ret);
2725 return -EINVAL;
2726 }
2727 ret = drm_dp_calc_pbn_mode(297000, 24);
2728 if (ret != 1063) {
2729 DRM_ERROR("PBN calculation test failed - clock %d, bpp %d, expected PBN %d, actual PBN %d.\n",
2730 297000, 24, 1063, ret);
2731 return -EINVAL;
2732 }
2733 return 0;
2734 }
2735
2736 /* we want to kick the TX after we've ack the up/down IRQs. */
2737 static void drm_dp_mst_kick_tx(struct drm_dp_mst_topology_mgr *mgr)
2738 {
2739 queue_work(system_long_wq, &mgr->tx_work);
2740 }
2741
2742 static void drm_dp_mst_dump_mstb(struct seq_file *m,
2743 struct drm_dp_mst_branch *mstb)
2744 {
2745 struct drm_dp_mst_port *port;
2746 int tabs = mstb->lct;
2747 char prefix[10];
2748 int i;
2749
2750 for (i = 0; i < tabs; i++)
2751 prefix[i] = '\t';
2752 prefix[i] = '\0';
2753
2754 seq_printf(m, "%smst: %p, %d\n", prefix, mstb, mstb->num_ports);
2755 list_for_each_entry(port, &mstb->ports, next) {
2756 seq_printf(m, "%sport: %d: input: %d: pdt: %d, ddps: %d ldps: %d, sdp: %d/%d, %p, conn: %p\n", prefix, port->port_num, port->input, port->pdt, port->ddps, port->ldps, port->num_sdp_streams, port->num_sdp_stream_sinks, port, port->connector);
2757 if (port->mstb)
2758 drm_dp_mst_dump_mstb(m, port->mstb);
2759 }
2760 }
2761
2762 static bool dump_dp_payload_table(struct drm_dp_mst_topology_mgr *mgr,
2763 char *buf)
2764 {
2765 int ret;
2766 int i;
2767 for (i = 0; i < 4; i++) {
2768 ret = drm_dp_dpcd_read(mgr->aux, DP_PAYLOAD_TABLE_UPDATE_STATUS + (i * 16), &buf[i * 16], 16);
2769 if (ret != 16)
2770 break;
2771 }
2772 if (i == 4)
2773 return true;
2774 return false;
2775 }
2776
2777 static void fetch_monitor_name(struct drm_dp_mst_topology_mgr *mgr,
2778 struct drm_dp_mst_port *port, char *name,
2779 int namelen)
2780 {
2781 struct edid *mst_edid;
2782
2783 mst_edid = drm_dp_mst_get_edid(port->connector, mgr, port);
2784 drm_edid_get_monitor_name(mst_edid, name, namelen);
2785 }
2786
2787 /**
2788 * drm_dp_mst_dump_topology(): dump topology to seq file.
2789 * @m: seq_file to dump output to
2790 * @mgr: manager to dump current topology for.
2791 *
2792 * helper to dump MST topology to a seq file for debugfs.
2793 */
2794 void drm_dp_mst_dump_topology(struct seq_file *m,
2795 struct drm_dp_mst_topology_mgr *mgr)
2796 {
2797 int i;
2798 struct drm_dp_mst_port *port;
2799
2800 mutex_lock(&mgr->lock);
2801 if (mgr->mst_primary)
2802 drm_dp_mst_dump_mstb(m, mgr->mst_primary);
2803
2804 /* dump VCPIs */
2805 mutex_unlock(&mgr->lock);
2806
2807 mutex_lock(&mgr->payload_lock);
2808 seq_printf(m, "vcpi: %lx %lx %d\n", mgr->payload_mask, mgr->vcpi_mask,
2809 mgr->max_payloads);
2810
2811 for (i = 0; i < mgr->max_payloads; i++) {
2812 if (mgr->proposed_vcpis[i]) {
2813 char name[14];
2814
2815 port = container_of(mgr->proposed_vcpis[i], struct drm_dp_mst_port, vcpi);
2816 fetch_monitor_name(mgr, port, name, sizeof(name));
2817 seq_printf(m, "vcpi %d: %d %d %d sink name: %s\n", i,
2818 port->port_num, port->vcpi.vcpi,
2819 port->vcpi.num_slots,
2820 (*name != 0) ? name : "Unknown");
2821 } else
2822 seq_printf(m, "vcpi %d:unused\n", i);
2823 }
2824 for (i = 0; i < mgr->max_payloads; i++) {
2825 seq_printf(m, "payload %d: %d, %d, %d\n",
2826 i,
2827 mgr->payloads[i].payload_state,
2828 mgr->payloads[i].start_slot,
2829 mgr->payloads[i].num_slots);
2830
2831
2832 }
2833 mutex_unlock(&mgr->payload_lock);
2834
2835 mutex_lock(&mgr->lock);
2836 if (mgr->mst_primary) {
2837 u8 buf[64];
2838 bool bret;
2839 int ret;
2840 ret = drm_dp_dpcd_read(mgr->aux, DP_DPCD_REV, buf, DP_RECEIVER_CAP_SIZE);
2841 seq_printf(m, "dpcd: ");
2842 for (i = 0; i < DP_RECEIVER_CAP_SIZE; i++)
2843 seq_printf(m, "%02x ", buf[i]);
2844 seq_printf(m, "\n");
2845 ret = drm_dp_dpcd_read(mgr->aux, DP_FAUX_CAP, buf, 2);
2846 seq_printf(m, "faux/mst: ");
2847 for (i = 0; i < 2; i++)
2848 seq_printf(m, "%02x ", buf[i]);
2849 seq_printf(m, "\n");
2850 ret = drm_dp_dpcd_read(mgr->aux, DP_MSTM_CTRL, buf, 1);
2851 seq_printf(m, "mst ctrl: ");
2852 for (i = 0; i < 1; i++)
2853 seq_printf(m, "%02x ", buf[i]);
2854 seq_printf(m, "\n");
2855
2856 /* dump the standard OUI branch header */
2857 ret = drm_dp_dpcd_read(mgr->aux, DP_BRANCH_OUI, buf, DP_BRANCH_OUI_HEADER_SIZE);
2858 seq_printf(m, "branch oui: ");
2859 for (i = 0; i < 0x3; i++)
2860 seq_printf(m, "%02x", buf[i]);
2861 seq_printf(m, " devid: ");
2862 for (i = 0x3; i < 0x8 && buf[i]; i++)
2863 seq_printf(m, "%c", buf[i]);
2864
2865 seq_printf(m, " revision: hw: %x.%x sw: %x.%x", buf[0x9] >> 4, buf[0x9] & 0xf, buf[0xa], buf[0xb]);
2866 seq_printf(m, "\n");
2867 bret = dump_dp_payload_table(mgr, buf);
2868 if (bret == true) {
2869 seq_printf(m, "payload table: ");
2870 for (i = 0; i < 63; i++)
2871 seq_printf(m, "%02x ", buf[i]);
2872 seq_printf(m, "\n");
2873 }
2874
2875 }
2876
2877 mutex_unlock(&mgr->lock);
2878
2879 }
2880 EXPORT_SYMBOL(drm_dp_mst_dump_topology);
2881
2882 static void drm_dp_tx_work(struct work_struct *work)
2883 {
2884 struct drm_dp_mst_topology_mgr *mgr = container_of(work, struct drm_dp_mst_topology_mgr, tx_work);
2885
2886 mutex_lock(&mgr->qlock);
2887 if (!list_empty(&mgr->tx_msg_downq))
2888 process_single_down_tx_qlock(mgr);
2889 mutex_unlock(&mgr->qlock);
2890 }
2891
2892 static void drm_dp_free_mst_port(struct kref *kref)
2893 {
2894 struct drm_dp_mst_port *port = container_of(kref, struct drm_dp_mst_port, kref);
2895 kref_put(&port->parent->kref, drm_dp_free_mst_branch_device);
2896 kfree(port);
2897 }
2898
2899 static void drm_dp_destroy_connector_work(struct work_struct *work)
2900 {
2901 struct drm_dp_mst_topology_mgr *mgr = container_of(work, struct drm_dp_mst_topology_mgr, destroy_connector_work);
2902 struct drm_dp_mst_port *port;
2903 bool send_hotplug = false;
2904 /*
2905 * Not a regular list traverse as we have to drop the destroy
2906 * connector lock before destroying the connector, to avoid AB->BA
2907 * ordering between this lock and the config mutex.
2908 */
2909 for (;;) {
2910 mutex_lock(&mgr->destroy_connector_lock);
2911 port = list_first_entry_or_null(&mgr->destroy_connector_list, struct drm_dp_mst_port, next);
2912 if (!port) {
2913 mutex_unlock(&mgr->destroy_connector_lock);
2914 break;
2915 }
2916 list_del(&port->next);
2917 mutex_unlock(&mgr->destroy_connector_lock);
2918
2919 kref_init(&port->kref);
2920 INIT_LIST_HEAD(&port->next);
2921
2922 mgr->cbs->destroy_connector(mgr, port->connector);
2923
2924 drm_dp_port_teardown_pdt(port, port->pdt);
2925 port->pdt = DP_PEER_DEVICE_NONE;
2926
2927 if (!port->input && port->vcpi.vcpi > 0) {
2928 drm_dp_mst_reset_vcpi_slots(mgr, port);
2929 drm_dp_update_payload_part1(mgr);
2930 drm_dp_mst_put_payload_id(mgr, port->vcpi.vcpi);
2931 }
2932
2933 kref_put(&port->kref, drm_dp_free_mst_port);
2934 send_hotplug = true;
2935 }
2936 if (send_hotplug)
2937 (*mgr->cbs->hotplug)(mgr);
2938 }
2939
2940 /**
2941 * drm_dp_mst_topology_mgr_init - initialise a topology manager
2942 * @mgr: manager struct to initialise
2943 * @dev: device providing this structure - for i2c addition.
2944 * @aux: DP helper aux channel to talk to this device
2945 * @max_dpcd_transaction_bytes: hw specific DPCD transaction limit
2946 * @max_payloads: maximum number of payloads this GPU can source
2947 * @conn_base_id: the connector object ID the MST device is connected to.
2948 *
2949 * Return 0 for success, or negative error code on failure
2950 */
2951 int drm_dp_mst_topology_mgr_init(struct drm_dp_mst_topology_mgr *mgr,
2952 struct device *dev, struct drm_dp_aux *aux,
2953 int max_dpcd_transaction_bytes,
2954 int max_payloads, int conn_base_id)
2955 {
2956 mutex_init(&mgr->lock);
2957 mutex_init(&mgr->qlock);
2958 mutex_init(&mgr->payload_lock);
2959 mutex_init(&mgr->destroy_connector_lock);
2960 INIT_LIST_HEAD(&mgr->tx_msg_downq);
2961 INIT_LIST_HEAD(&mgr->destroy_connector_list);
2962 INIT_WORK(&mgr->work, drm_dp_mst_link_probe_work);
2963 INIT_WORK(&mgr->tx_work, drm_dp_tx_work);
2964 INIT_WORK(&mgr->destroy_connector_work, drm_dp_destroy_connector_work);
2965 init_waitqueue_head(&mgr->tx_waitq);
2966 mgr->dev = dev;
2967 mgr->aux = aux;
2968 mgr->max_dpcd_transaction_bytes = max_dpcd_transaction_bytes;
2969 mgr->max_payloads = max_payloads;
2970 mgr->conn_base_id = conn_base_id;
2971 if (max_payloads + 1 > sizeof(mgr->payload_mask) * 8 ||
2972 max_payloads + 1 > sizeof(mgr->vcpi_mask) * 8)
2973 return -EINVAL;
2974 mgr->payloads = kcalloc(max_payloads, sizeof(struct drm_dp_payload), GFP_KERNEL);
2975 if (!mgr->payloads)
2976 return -ENOMEM;
2977 mgr->proposed_vcpis = kcalloc(max_payloads, sizeof(struct drm_dp_vcpi *), GFP_KERNEL);
2978 if (!mgr->proposed_vcpis)
2979 return -ENOMEM;
2980 set_bit(0, &mgr->payload_mask);
2981 if (test_calc_pbn_mode() < 0)
2982 DRM_ERROR("MST PBN self-test failed\n");
2983
2984 return 0;
2985 }
2986 EXPORT_SYMBOL(drm_dp_mst_topology_mgr_init);
2987
2988 /**
2989 * drm_dp_mst_topology_mgr_destroy() - destroy topology manager.
2990 * @mgr: manager to destroy
2991 */
2992 void drm_dp_mst_topology_mgr_destroy(struct drm_dp_mst_topology_mgr *mgr)
2993 {
2994 flush_work(&mgr->work);
2995 flush_work(&mgr->destroy_connector_work);
2996 mutex_lock(&mgr->payload_lock);
2997 kfree(mgr->payloads);
2998 mgr->payloads = NULL;
2999 kfree(mgr->proposed_vcpis);
3000 mgr->proposed_vcpis = NULL;
3001 mutex_unlock(&mgr->payload_lock);
3002 mgr->dev = NULL;
3003 mgr->aux = NULL;
3004 }
3005 EXPORT_SYMBOL(drm_dp_mst_topology_mgr_destroy);
3006
3007 /* I2C device */
3008 static int drm_dp_mst_i2c_xfer(struct i2c_adapter *adapter, struct i2c_msg *msgs,
3009 int num)
3010 {
3011 struct drm_dp_aux *aux = adapter->algo_data;
3012 struct drm_dp_mst_port *port = container_of(aux, struct drm_dp_mst_port, aux);
3013 struct drm_dp_mst_branch *mstb;
3014 struct drm_dp_mst_topology_mgr *mgr = port->mgr;
3015 unsigned int i;
3016 bool reading = false;
3017 struct drm_dp_sideband_msg_req_body msg;
3018 struct drm_dp_sideband_msg_tx *txmsg = NULL;
3019 int ret;
3020
3021 mstb = drm_dp_get_validated_mstb_ref(mgr, port->parent);
3022 if (!mstb)
3023 return -EREMOTEIO;
3024
3025 /* construct i2c msg */
3026 /* see if last msg is a read */
3027 if (msgs[num - 1].flags & I2C_M_RD)
3028 reading = true;
3029
3030 if (!reading || (num - 1 > DP_REMOTE_I2C_READ_MAX_TRANSACTIONS)) {
3031 DRM_DEBUG_KMS("Unsupported I2C transaction for MST device\n");
3032 ret = -EIO;
3033 goto out;
3034 }
3035
3036 memset(&msg, 0, sizeof(msg));
3037 msg.req_type = DP_REMOTE_I2C_READ;
3038 msg.u.i2c_read.num_transactions = num - 1;
3039 msg.u.i2c_read.port_number = port->port_num;
3040 for (i = 0; i < num - 1; i++) {
3041 msg.u.i2c_read.transactions[i].i2c_dev_id = msgs[i].addr;
3042 msg.u.i2c_read.transactions[i].num_bytes = msgs[i].len;
3043 msg.u.i2c_read.transactions[i].bytes = msgs[i].buf;
3044 }
3045 msg.u.i2c_read.read_i2c_device_id = msgs[num - 1].addr;
3046 msg.u.i2c_read.num_bytes_read = msgs[num - 1].len;
3047
3048 txmsg = kzalloc(sizeof(*txmsg), GFP_KERNEL);
3049 if (!txmsg) {
3050 ret = -ENOMEM;
3051 goto out;
3052 }
3053
3054 txmsg->dst = mstb;
3055 drm_dp_encode_sideband_req(&msg, txmsg);
3056
3057 drm_dp_queue_down_tx(mgr, txmsg);
3058
3059 ret = drm_dp_mst_wait_tx_reply(mstb, txmsg);
3060 if (ret > 0) {
3061
3062 if (txmsg->reply.reply_type == 1) { /* got a NAK back */
3063 ret = -EREMOTEIO;
3064 goto out;
3065 }
3066 if (txmsg->reply.u.remote_i2c_read_ack.num_bytes != msgs[num - 1].len) {
3067 ret = -EIO;
3068 goto out;
3069 }
3070 memcpy(msgs[num - 1].buf, txmsg->reply.u.remote_i2c_read_ack.bytes, msgs[num - 1].len);
3071 ret = num;
3072 }
3073 out:
3074 kfree(txmsg);
3075 drm_dp_put_mst_branch_device(mstb);
3076 return ret;
3077 }
3078
3079 static u32 drm_dp_mst_i2c_functionality(struct i2c_adapter *adapter)
3080 {
3081 return I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL |
3082 I2C_FUNC_SMBUS_READ_BLOCK_DATA |
3083 I2C_FUNC_SMBUS_BLOCK_PROC_CALL |
3084 I2C_FUNC_10BIT_ADDR;
3085 }
3086
3087 static const struct i2c_algorithm drm_dp_mst_i2c_algo = {
3088 .functionality = drm_dp_mst_i2c_functionality,
3089 .master_xfer = drm_dp_mst_i2c_xfer,
3090 };
3091
3092 /**
3093 * drm_dp_mst_register_i2c_bus() - register an I2C adapter for I2C-over-AUX
3094 * @aux: DisplayPort AUX channel
3095 *
3096 * Returns 0 on success or a negative error code on failure.
3097 */
3098 static int drm_dp_mst_register_i2c_bus(struct drm_dp_aux *aux)
3099 {
3100 aux->ddc.algo = &drm_dp_mst_i2c_algo;
3101 aux->ddc.algo_data = aux;
3102 aux->ddc.retries = 3;
3103
3104 aux->ddc.class = I2C_CLASS_DDC;
3105 aux->ddc.owner = THIS_MODULE;
3106 aux->ddc.dev.parent = aux->dev;
3107 aux->ddc.dev.of_node = aux->dev->of_node;
3108
3109 strlcpy(aux->ddc.name, aux->name ? aux->name : dev_name(aux->dev),
3110 sizeof(aux->ddc.name));
3111
3112 return i2c_add_adapter(&aux->ddc);
3113 }
3114
3115 /**
3116 * drm_dp_mst_unregister_i2c_bus() - unregister an I2C-over-AUX adapter
3117 * @aux: DisplayPort AUX channel
3118 */
3119 static void drm_dp_mst_unregister_i2c_bus(struct drm_dp_aux *aux)
3120 {
3121 i2c_del_adapter(&aux->ddc);
3122 }
Linux with added FPC-III support