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Linux 4.19.133
[linux/fpc-iii.git] / drivers / soundwire / bus.c
blobdf172bf3925f6415747c6d4f1b35928432e95270
1 // SPDX-License-Identifier: (GPL-2.0 OR BSD-3-Clause)
2 // Copyright(c) 2015-17 Intel Corporation.
3
4 #include <linux/acpi.h>
5 #include <linux/mod_devicetable.h>
6 #include <linux/pm_runtime.h>
7 #include <linux/soundwire/sdw_registers.h>
8 #include <linux/soundwire/sdw.h>
9 #include "bus.h"
10
11 /**
12 * sdw_add_bus_master() - add a bus Master instance
13 * @bus: bus instance
14 *
15 * Initializes the bus instance, read properties and create child
16 * devices.
17 */
18 int sdw_add_bus_master(struct sdw_bus *bus)
19 {
20 struct sdw_master_prop *prop = NULL;
21 int ret;
22
23 if (!bus->dev) {
24 pr_err("SoundWire bus has no device");
25 return -ENODEV;
26 }
27
28 if (!bus->ops) {
29 dev_err(bus->dev, "SoundWire Bus ops are not set");
30 return -EINVAL;
31 }
32
33 mutex_init(&bus->msg_lock);
34 mutex_init(&bus->bus_lock);
35 INIT_LIST_HEAD(&bus->slaves);
36 INIT_LIST_HEAD(&bus->m_rt_list);
37
38 if (bus->ops->read_prop) {
39 ret = bus->ops->read_prop(bus);
40 if (ret < 0) {
41 dev_err(bus->dev, "Bus read properties failed:%d", ret);
42 return ret;
43 }
44 }
45
46 /*
47 * Device numbers in SoundWire are 0 thru 15. Enumeration device
48 * number (0), Broadcast device number (15), Group numbers (12 and
49 * 13) and Master device number (14) are not used for assignment so
50 * mask these and other higher bits.
51 */
52
53 /* Set higher order bits */
54 *bus->assigned = ~GENMASK(SDW_BROADCAST_DEV_NUM, SDW_ENUM_DEV_NUM);
55
56 /* Set enumuration device number and broadcast device number */
57 set_bit(SDW_ENUM_DEV_NUM, bus->assigned);
58 set_bit(SDW_BROADCAST_DEV_NUM, bus->assigned);
59
60 /* Set group device numbers and master device number */
61 set_bit(SDW_GROUP12_DEV_NUM, bus->assigned);
62 set_bit(SDW_GROUP13_DEV_NUM, bus->assigned);
63 set_bit(SDW_MASTER_DEV_NUM, bus->assigned);
64
65 /*
66 * SDW is an enumerable bus, but devices can be powered off. So,
67 * they won't be able to report as present.
68 *
69 * Create Slave devices based on Slaves described in
70 * the respective firmware (ACPI/DT)
71 */
72 if (IS_ENABLED(CONFIG_ACPI) && ACPI_HANDLE(bus->dev))
73 ret = sdw_acpi_find_slaves(bus);
74 else
75 ret = -ENOTSUPP; /* No ACPI/DT so error out */
76
77 if (ret) {
78 dev_err(bus->dev, "Finding slaves failed:%d\n", ret);
79 return ret;
80 }
81
82 /*
83 * Initialize clock values based on Master properties. The max
84 * frequency is read from max_freq property. Current assumption
85 * is that the bus will start at highest clock frequency when
86 * powered on.
87 *
88 * Default active bank will be 0 as out of reset the Slaves have
89 * to start with bank 0 (Table 40 of Spec)
90 */
91 prop = &bus->prop;
92 bus->params.max_dr_freq = prop->max_freq * SDW_DOUBLE_RATE_FACTOR;
93 bus->params.curr_dr_freq = bus->params.max_dr_freq;
94 bus->params.curr_bank = SDW_BANK0;
95 bus->params.next_bank = SDW_BANK1;
96
97 return 0;
98 }
99 EXPORT_SYMBOL(sdw_add_bus_master);
100
101 static int sdw_delete_slave(struct device *dev, void *data)
102 {
103 struct sdw_slave *slave = dev_to_sdw_dev(dev);
104 struct sdw_bus *bus = slave->bus;
105
106 mutex_lock(&bus->bus_lock);
107
108 if (slave->dev_num) /* clear dev_num if assigned */
109 clear_bit(slave->dev_num, bus->assigned);
110
111 list_del_init(&slave->node);
112 mutex_unlock(&bus->bus_lock);
113
114 device_unregister(dev);
115 return 0;
116 }
117
118 /**
119 * sdw_delete_bus_master() - delete the bus master instance
120 * @bus: bus to be deleted
121 *
122 * Remove the instance, delete the child devices.
123 */
124 void sdw_delete_bus_master(struct sdw_bus *bus)
125 {
126 device_for_each_child(bus->dev, NULL, sdw_delete_slave);
127 }
128 EXPORT_SYMBOL(sdw_delete_bus_master);
129
130 /*
131 * SDW IO Calls
132 */
133
134 static inline int find_response_code(enum sdw_command_response resp)
135 {
136 switch (resp) {
137 case SDW_CMD_OK:
138 return 0;
139
140 case SDW_CMD_IGNORED:
141 return -ENODATA;
142
143 case SDW_CMD_TIMEOUT:
144 return -ETIMEDOUT;
145
146 default:
147 return -EIO;
148 }
149 }
150
151 static inline int do_transfer(struct sdw_bus *bus, struct sdw_msg *msg)
152 {
153 int retry = bus->prop.err_threshold;
154 enum sdw_command_response resp;
155 int ret = 0, i;
156
157 for (i = 0; i <= retry; i++) {
158 resp = bus->ops->xfer_msg(bus, msg);
159 ret = find_response_code(resp);
160
161 /* if cmd is ok or ignored return */
162 if (ret == 0 || ret == -ENODATA)
163 return ret;
164 }
165
166 return ret;
167 }
168
169 static inline int do_transfer_defer(struct sdw_bus *bus,
170 struct sdw_msg *msg, struct sdw_defer *defer)
171 {
172 int retry = bus->prop.err_threshold;
173 enum sdw_command_response resp;
174 int ret = 0, i;
175
176 defer->msg = msg;
177 defer->length = msg->len;
178 init_completion(&defer->complete);
179
180 for (i = 0; i <= retry; i++) {
181 resp = bus->ops->xfer_msg_defer(bus, msg, defer);
182 ret = find_response_code(resp);
183 /* if cmd is ok or ignored return */
184 if (ret == 0 || ret == -ENODATA)
185 return ret;
186 }
187
188 return ret;
189 }
190
191 static int sdw_reset_page(struct sdw_bus *bus, u16 dev_num)
192 {
193 int retry = bus->prop.err_threshold;
194 enum sdw_command_response resp;
195 int ret = 0, i;
196
197 for (i = 0; i <= retry; i++) {
198 resp = bus->ops->reset_page_addr(bus, dev_num);
199 ret = find_response_code(resp);
200 /* if cmd is ok or ignored return */
201 if (ret == 0 || ret == -ENODATA)
202 return ret;
203 }
204
205 return ret;
206 }
207
208 /**
209 * sdw_transfer() - Synchronous transfer message to a SDW Slave device
210 * @bus: SDW bus
211 * @msg: SDW message to be xfered
212 */
213 int sdw_transfer(struct sdw_bus *bus, struct sdw_msg *msg)
214 {
215 int ret;
216
217 mutex_lock(&bus->msg_lock);
218
219 ret = do_transfer(bus, msg);
220 if (ret != 0 && ret != -ENODATA)
221 dev_err(bus->dev, "trf on Slave %d failed:%d\n",
222 msg->dev_num, ret);
223
224 if (msg->page)
225 sdw_reset_page(bus, msg->dev_num);
226
227 mutex_unlock(&bus->msg_lock);
228
229 return ret;
230 }
231
232 /**
233 * sdw_transfer_defer() - Asynchronously transfer message to a SDW Slave device
234 * @bus: SDW bus
235 * @msg: SDW message to be xfered
236 * @defer: Defer block for signal completion
237 *
238 * Caller needs to hold the msg_lock lock while calling this
239 */
240 int sdw_transfer_defer(struct sdw_bus *bus, struct sdw_msg *msg,
241 struct sdw_defer *defer)
242 {
243 int ret;
244
245 if (!bus->ops->xfer_msg_defer)
246 return -ENOTSUPP;
247
248 ret = do_transfer_defer(bus, msg, defer);
249 if (ret != 0 && ret != -ENODATA)
250 dev_err(bus->dev, "Defer trf on Slave %d failed:%d\n",
251 msg->dev_num, ret);
252
253 if (msg->page)
254 sdw_reset_page(bus, msg->dev_num);
255
256 return ret;
257 }
258
259
260 int sdw_fill_msg(struct sdw_msg *msg, struct sdw_slave *slave,
261 u32 addr, size_t count, u16 dev_num, u8 flags, u8 *buf)
262 {
263 memset(msg, 0, sizeof(*msg));
264 msg->addr = addr; /* addr is 16 bit and truncated here */
265 msg->len = count;
266 msg->dev_num = dev_num;
267 msg->flags = flags;
268 msg->buf = buf;
269 msg->ssp_sync = false;
270 msg->page = false;
271
272 if (addr < SDW_REG_NO_PAGE) { /* no paging area */
273 return 0;
274 } else if (addr >= SDW_REG_MAX) { /* illegal addr */
275 pr_err("SDW: Invalid address %x passed\n", addr);
276 return -EINVAL;
277 }
278
279 if (addr < SDW_REG_OPTIONAL_PAGE) { /* 32k but no page */
280 if (slave && !slave->prop.paging_support)
281 return 0;
282 /* no need for else as that will fall thru to paging */
283 }
284
285 /* paging mandatory */
286 if (dev_num == SDW_ENUM_DEV_NUM || dev_num == SDW_BROADCAST_DEV_NUM) {
287 pr_err("SDW: Invalid device for paging :%d\n", dev_num);
288 return -EINVAL;
289 }
290
291 if (!slave) {
292 pr_err("SDW: No slave for paging addr\n");
293 return -EINVAL;
294 } else if (!slave->prop.paging_support) {
295 dev_err(&slave->dev,
296 "address %x needs paging but no support", addr);
297 return -EINVAL;
298 }
299
300 msg->addr_page1 = (addr >> SDW_REG_SHIFT(SDW_SCP_ADDRPAGE1_MASK));
301 msg->addr_page2 = (addr >> SDW_REG_SHIFT(SDW_SCP_ADDRPAGE2_MASK));
302 msg->addr |= BIT(15);
303 msg->page = true;
304
305 return 0;
306 }
307
308 /**
309 * sdw_nread() - Read "n" contiguous SDW Slave registers
310 * @slave: SDW Slave
311 * @addr: Register address
312 * @count: length
313 * @val: Buffer for values to be read
314 */
315 int sdw_nread(struct sdw_slave *slave, u32 addr, size_t count, u8 *val)
316 {
317 struct sdw_msg msg;
318 int ret;
319
320 ret = sdw_fill_msg(&msg, slave, addr, count,
321 slave->dev_num, SDW_MSG_FLAG_READ, val);
322 if (ret < 0)
323 return ret;
324
325 ret = pm_runtime_get_sync(slave->bus->dev);
326 if (ret < 0)
327 return ret;
328
329 ret = sdw_transfer(slave->bus, &msg);
330 pm_runtime_put(slave->bus->dev);
331
332 return ret;
333 }
334 EXPORT_SYMBOL(sdw_nread);
335
336 /**
337 * sdw_nwrite() - Write "n" contiguous SDW Slave registers
338 * @slave: SDW Slave
339 * @addr: Register address
340 * @count: length
341 * @val: Buffer for values to be read
342 */
343 int sdw_nwrite(struct sdw_slave *slave, u32 addr, size_t count, u8 *val)
344 {
345 struct sdw_msg msg;
346 int ret;
347
348 ret = sdw_fill_msg(&msg, slave, addr, count,
349 slave->dev_num, SDW_MSG_FLAG_WRITE, val);
350 if (ret < 0)
351 return ret;
352
353 ret = pm_runtime_get_sync(slave->bus->dev);
354 if (ret < 0)
355 return ret;
356
357 ret = sdw_transfer(slave->bus, &msg);
358 pm_runtime_put(slave->bus->dev);
359
360 return ret;
361 }
362 EXPORT_SYMBOL(sdw_nwrite);
363
364 /**
365 * sdw_read() - Read a SDW Slave register
366 * @slave: SDW Slave
367 * @addr: Register address
368 */
369 int sdw_read(struct sdw_slave *slave, u32 addr)
370 {
371 u8 buf;
372 int ret;
373
374 ret = sdw_nread(slave, addr, 1, &buf);
375 if (ret < 0)
376 return ret;
377 else
378 return buf;
379 }
380 EXPORT_SYMBOL(sdw_read);
381
382 /**
383 * sdw_write() - Write a SDW Slave register
384 * @slave: SDW Slave
385 * @addr: Register address
386 * @value: Register value
387 */
388 int sdw_write(struct sdw_slave *slave, u32 addr, u8 value)
389 {
390 return sdw_nwrite(slave, addr, 1, &value);
391
392 }
393 EXPORT_SYMBOL(sdw_write);
394
395 /*
396 * SDW alert handling
397 */
398
399 /* called with bus_lock held */
400 static struct sdw_slave *sdw_get_slave(struct sdw_bus *bus, int i)
401 {
402 struct sdw_slave *slave = NULL;
403
404 list_for_each_entry(slave, &bus->slaves, node) {
405 if (slave->dev_num == i)
406 return slave;
407 }
408
409 return NULL;
410 }
411
412 static int sdw_compare_devid(struct sdw_slave *slave, struct sdw_slave_id id)
413 {
414
415 if ((slave->id.unique_id != id.unique_id) ||
416 (slave->id.mfg_id != id.mfg_id) ||
417 (slave->id.part_id != id.part_id) ||
418 (slave->id.class_id != id.class_id))
419 return -ENODEV;
420
421 return 0;
422 }
423
424 /* called with bus_lock held */
425 static int sdw_get_device_num(struct sdw_slave *slave)
426 {
427 int bit;
428
429 bit = find_first_zero_bit(slave->bus->assigned, SDW_MAX_DEVICES);
430 if (bit == SDW_MAX_DEVICES) {
431 bit = -ENODEV;
432 goto err;
433 }
434
435 /*
436 * Do not update dev_num in Slave data structure here,
437 * Update once program dev_num is successful
438 */
439 set_bit(bit, slave->bus->assigned);
440
441 err:
442 return bit;
443 }
444
445 static int sdw_assign_device_num(struct sdw_slave *slave)
446 {
447 int ret, dev_num;
448
449 /* check first if device number is assigned, if so reuse that */
450 if (!slave->dev_num) {
451 mutex_lock(&slave->bus->bus_lock);
452 dev_num = sdw_get_device_num(slave);
453 mutex_unlock(&slave->bus->bus_lock);
454 if (dev_num < 0) {
455 dev_err(slave->bus->dev, "Get dev_num failed: %d",
456 dev_num);
457 return dev_num;
458 }
459 } else {
460 dev_info(slave->bus->dev,
461 "Slave already registered dev_num:%d",
462 slave->dev_num);
463
464 /* Clear the slave->dev_num to transfer message on device 0 */
465 dev_num = slave->dev_num;
466 slave->dev_num = 0;
467
468 }
469
470 ret = sdw_write(slave, SDW_SCP_DEVNUMBER, dev_num);
471 if (ret < 0) {
472 dev_err(&slave->dev, "Program device_num failed: %d", ret);
473 return ret;
474 }
475
476 /* After xfer of msg, restore dev_num */
477 slave->dev_num = dev_num;
478
479 return 0;
480 }
481
482 void sdw_extract_slave_id(struct sdw_bus *bus,
483 u64 addr, struct sdw_slave_id *id)
484 {
485 dev_dbg(bus->dev, "SDW Slave Addr: %llx", addr);
486
487 /*
488 * Spec definition
489 * Register Bit Contents
490 * DevId_0 [7:4] 47:44 sdw_version
491 * DevId_0 [3:0] 43:40 unique_id
492 * DevId_1 39:32 mfg_id [15:8]
493 * DevId_2 31:24 mfg_id [7:0]
494 * DevId_3 23:16 part_id [15:8]
495 * DevId_4 15:08 part_id [7:0]
496 * DevId_5 07:00 class_id
497 */
498 id->sdw_version = (addr >> 44) & GENMASK(3, 0);
499 id->unique_id = (addr >> 40) & GENMASK(3, 0);
500 id->mfg_id = (addr >> 24) & GENMASK(15, 0);
501 id->part_id = (addr >> 8) & GENMASK(15, 0);
502 id->class_id = addr & GENMASK(7, 0);
503
504 dev_dbg(bus->dev,
505 "SDW Slave class_id %x, part_id %x, mfg_id %x, unique_id %x, version %x",
506 id->class_id, id->part_id, id->mfg_id,
507 id->unique_id, id->sdw_version);
508
509 }
510
511 static int sdw_program_device_num(struct sdw_bus *bus)
512 {
513 u8 buf[SDW_NUM_DEV_ID_REGISTERS] = {0};
514 struct sdw_slave *slave, *_s;
515 struct sdw_slave_id id;
516 struct sdw_msg msg;
517 bool found = false;
518 int count = 0, ret;
519 u64 addr;
520
521 /* No Slave, so use raw xfer api */
522 ret = sdw_fill_msg(&msg, NULL, SDW_SCP_DEVID_0,
523 SDW_NUM_DEV_ID_REGISTERS, 0, SDW_MSG_FLAG_READ, buf);
524 if (ret < 0)
525 return ret;
526
527 do {
528 ret = sdw_transfer(bus, &msg);
529 if (ret == -ENODATA) { /* end of device id reads */
530 ret = 0;
531 break;
532 }
533 if (ret < 0) {
534 dev_err(bus->dev, "DEVID read fail:%d\n", ret);
535 break;
536 }
537
538 /*
539 * Construct the addr and extract. Cast the higher shift
540 * bits to avoid truncation due to size limit.
541 */
542 addr = buf[5] | (buf[4] << 8) | (buf[3] << 16) |
543 ((u64)buf[2] << 24) | ((u64)buf[1] << 32) |
544 ((u64)buf[0] << 40);
545
546 sdw_extract_slave_id(bus, addr, &id);
547
548 /* Now compare with entries */
549 list_for_each_entry_safe(slave, _s, &bus->slaves, node) {
550 if (sdw_compare_devid(slave, id) == 0) {
551 found = true;
552
553 /*
554 * Assign a new dev_num to this Slave and
555 * not mark it present. It will be marked
556 * present after it reports ATTACHED on new
557 * dev_num
558 */
559 ret = sdw_assign_device_num(slave);
560 if (ret) {
561 dev_err(slave->bus->dev,
562 "Assign dev_num failed:%d",
563 ret);
564 return ret;
565 }
566
567 break;
568 }
569 }
570
571 if (found == false) {
572 /* TODO: Park this device in Group 13 */
573 dev_err(bus->dev, "Slave Entry not found");
574 }
575
576 count++;
577
578 /*
579 * Check till error out or retry (count) exhausts.
580 * Device can drop off and rejoin during enumeration
581 * so count till twice the bound.
582 */
583
584 } while (ret == 0 && count < (SDW_MAX_DEVICES * 2));
585
586 return ret;
587 }
588
589 static void sdw_modify_slave_status(struct sdw_slave *slave,
590 enum sdw_slave_status status)
591 {
592 mutex_lock(&slave->bus->bus_lock);
593 slave->status = status;
594 mutex_unlock(&slave->bus->bus_lock);
595 }
596
597 int sdw_configure_dpn_intr(struct sdw_slave *slave,
598 int port, bool enable, int mask)
599 {
600 u32 addr;
601 int ret;
602 u8 val = 0;
603
604 addr = SDW_DPN_INTMASK(port);
605
606 /* Set/Clear port ready interrupt mask */
607 if (enable) {
608 val |= mask;
609 val |= SDW_DPN_INT_PORT_READY;
610 } else {
611 val &= ~(mask);
612 val &= ~SDW_DPN_INT_PORT_READY;
613 }
614
615 ret = sdw_update(slave, addr, (mask | SDW_DPN_INT_PORT_READY), val);
616 if (ret < 0)
617 dev_err(slave->bus->dev,
618 "SDW_DPN_INTMASK write failed:%d", val);
619
620 return ret;
621 }
622
623 static int sdw_initialize_slave(struct sdw_slave *slave)
624 {
625 struct sdw_slave_prop *prop = &slave->prop;
626 int ret;
627 u8 val;
628
629 /*
630 * Set bus clash, parity and SCP implementation
631 * defined interrupt mask
632 * TODO: Read implementation defined interrupt mask
633 * from Slave property
634 */
635 val = SDW_SCP_INT1_IMPL_DEF | SDW_SCP_INT1_BUS_CLASH |
636 SDW_SCP_INT1_PARITY;
637
638 /* Enable SCP interrupts */
639 ret = sdw_update(slave, SDW_SCP_INTMASK1, val, val);
640 if (ret < 0) {
641 dev_err(slave->bus->dev,
642 "SDW_SCP_INTMASK1 write failed:%d", ret);
643 return ret;
644 }
645
646 /* No need to continue if DP0 is not present */
647 if (!slave->prop.dp0_prop)
648 return 0;
649
650 /* Enable DP0 interrupts */
651 val = prop->dp0_prop->device_interrupts;
652 val |= SDW_DP0_INT_PORT_READY | SDW_DP0_INT_BRA_FAILURE;
653
654 ret = sdw_update(slave, SDW_DP0_INTMASK, val, val);
655 if (ret < 0) {
656 dev_err(slave->bus->dev,
657 "SDW_DP0_INTMASK read failed:%d", ret);
658 return val;
659 }
660
661 return 0;
662 }
663
664 static int sdw_handle_dp0_interrupt(struct sdw_slave *slave, u8 *slave_status)
665 {
666 u8 clear = 0, impl_int_mask;
667 int status, status2, ret, count = 0;
668
669 status = sdw_read(slave, SDW_DP0_INT);
670 if (status < 0) {
671 dev_err(slave->bus->dev,
672 "SDW_DP0_INT read failed:%d", status);
673 return status;
674 }
675
676 do {
677
678 if (status & SDW_DP0_INT_TEST_FAIL) {
679 dev_err(&slave->dev, "Test fail for port 0");
680 clear |= SDW_DP0_INT_TEST_FAIL;
681 }
682
683 /*
684 * Assumption: PORT_READY interrupt will be received only for
685 * ports implementing Channel Prepare state machine (CP_SM)
686 */
687
688 if (status & SDW_DP0_INT_PORT_READY) {
689 complete(&slave->port_ready[0]);
690 clear |= SDW_DP0_INT_PORT_READY;
691 }
692
693 if (status & SDW_DP0_INT_BRA_FAILURE) {
694 dev_err(&slave->dev, "BRA failed");
695 clear |= SDW_DP0_INT_BRA_FAILURE;
696 }
697
698 impl_int_mask = SDW_DP0_INT_IMPDEF1 |
699 SDW_DP0_INT_IMPDEF2 | SDW_DP0_INT_IMPDEF3;
700
701 if (status & impl_int_mask) {
702 clear |= impl_int_mask;
703 *slave_status = clear;
704 }
705
706 /* clear the interrupt */
707 ret = sdw_write(slave, SDW_DP0_INT, clear);
708 if (ret < 0) {
709 dev_err(slave->bus->dev,
710 "SDW_DP0_INT write failed:%d", ret);
711 return ret;
712 }
713
714 /* Read DP0 interrupt again */
715 status2 = sdw_read(slave, SDW_DP0_INT);
716 if (status2 < 0) {
717 dev_err(slave->bus->dev,
718 "SDW_DP0_INT read failed:%d", status2);
719 return status2;
720 }
721 status &= status2;
722
723 count++;
724
725 /* we can get alerts while processing so keep retrying */
726 } while (status != 0 && count < SDW_READ_INTR_CLEAR_RETRY);
727
728 if (count == SDW_READ_INTR_CLEAR_RETRY)
729 dev_warn(slave->bus->dev, "Reached MAX_RETRY on DP0 read");
730
731 return ret;
732 }
733
734 static int sdw_handle_port_interrupt(struct sdw_slave *slave,
735 int port, u8 *slave_status)
736 {
737 u8 clear = 0, impl_int_mask;
738 int status, status2, ret, count = 0;
739 u32 addr;
740
741 if (port == 0)
742 return sdw_handle_dp0_interrupt(slave, slave_status);
743
744 addr = SDW_DPN_INT(port);
745 status = sdw_read(slave, addr);
746 if (status < 0) {
747 dev_err(slave->bus->dev,
748 "SDW_DPN_INT read failed:%d", status);
749
750 return status;
751 }
752
753 do {
754
755 if (status & SDW_DPN_INT_TEST_FAIL) {
756 dev_err(&slave->dev, "Test fail for port:%d", port);
757 clear |= SDW_DPN_INT_TEST_FAIL;
758 }
759
760 /*
761 * Assumption: PORT_READY interrupt will be received only
762 * for ports implementing CP_SM.
763 */
764 if (status & SDW_DPN_INT_PORT_READY) {
765 complete(&slave->port_ready[port]);
766 clear |= SDW_DPN_INT_PORT_READY;
767 }
768
769 impl_int_mask = SDW_DPN_INT_IMPDEF1 |
770 SDW_DPN_INT_IMPDEF2 | SDW_DPN_INT_IMPDEF3;
771
772
773 if (status & impl_int_mask) {
774 clear |= impl_int_mask;
775 *slave_status = clear;
776 }
777
778 /* clear the interrupt */
779 ret = sdw_write(slave, addr, clear);
780 if (ret < 0) {
781 dev_err(slave->bus->dev,
782 "SDW_DPN_INT write failed:%d", ret);
783 return ret;
784 }
785
786 /* Read DPN interrupt again */
787 status2 = sdw_read(slave, addr);
788 if (status2 < 0) {
789 dev_err(slave->bus->dev,
790 "SDW_DPN_INT read failed:%d", status2);
791 return status2;
792 }
793 status &= status2;
794
795 count++;
796
797 /* we can get alerts while processing so keep retrying */
798 } while (status != 0 && count < SDW_READ_INTR_CLEAR_RETRY);
799
800 if (count == SDW_READ_INTR_CLEAR_RETRY)
801 dev_warn(slave->bus->dev, "Reached MAX_RETRY on port read");
802
803 return ret;
804 }
805
806 static int sdw_handle_slave_alerts(struct sdw_slave *slave)
807 {
808 struct sdw_slave_intr_status slave_intr;
809 u8 clear = 0, bit, port_status[15] = {0};
810 int port_num, stat, ret, count = 0;
811 unsigned long port;
812 bool slave_notify = false;
813 u8 buf, buf2[2], _buf, _buf2[2];
814
815 sdw_modify_slave_status(slave, SDW_SLAVE_ALERT);
816
817 /* Read Instat 1, Instat 2 and Instat 3 registers */
818 buf = ret = sdw_read(slave, SDW_SCP_INT1);
819 if (ret < 0) {
820 dev_err(slave->bus->dev,
821 "SDW_SCP_INT1 read failed:%d", ret);
822 return ret;
823 }
824
825 ret = sdw_nread(slave, SDW_SCP_INTSTAT2, 2, buf2);
826 if (ret < 0) {
827 dev_err(slave->bus->dev,
828 "SDW_SCP_INT2/3 read failed:%d", ret);
829 return ret;
830 }
831
832 do {
833 /*
834 * Check parity, bus clash and Slave (impl defined)
835 * interrupt
836 */
837 if (buf & SDW_SCP_INT1_PARITY) {
838 dev_err(&slave->dev, "Parity error detected");
839 clear |= SDW_SCP_INT1_PARITY;
840 }
841
842 if (buf & SDW_SCP_INT1_BUS_CLASH) {
843 dev_err(&slave->dev, "Bus clash error detected");
844 clear |= SDW_SCP_INT1_BUS_CLASH;
845 }
846
847 /*
848 * When bus clash or parity errors are detected, such errors
849 * are unlikely to be recoverable errors.
850 * TODO: In such scenario, reset bus. Make this configurable
851 * via sysfs property with bus reset being the default.
852 */
853
854 if (buf & SDW_SCP_INT1_IMPL_DEF) {
855 dev_dbg(&slave->dev, "Slave impl defined interrupt\n");
856 clear |= SDW_SCP_INT1_IMPL_DEF;
857 slave_notify = true;
858 }
859
860 /* Check port 0 - 3 interrupts */
861 port = buf & SDW_SCP_INT1_PORT0_3;
862
863 /* To get port number corresponding to bits, shift it */
864 port = port >> SDW_REG_SHIFT(SDW_SCP_INT1_PORT0_3);
865 for_each_set_bit(bit, &port, 8) {
866 sdw_handle_port_interrupt(slave, bit,
867 &port_status[bit]);
868
869 }
870
871 /* Check if cascade 2 interrupt is present */
872 if (buf & SDW_SCP_INT1_SCP2_CASCADE) {
873 port = buf2[0] & SDW_SCP_INTSTAT2_PORT4_10;
874 for_each_set_bit(bit, &port, 8) {
875 /* scp2 ports start from 4 */
876 port_num = bit + 3;
877 sdw_handle_port_interrupt(slave,
878 port_num,
879 &port_status[port_num]);
880 }
881 }
882
883 /* now check last cascade */
884 if (buf2[0] & SDW_SCP_INTSTAT2_SCP3_CASCADE) {
885 port = buf2[1] & SDW_SCP_INTSTAT3_PORT11_14;
886 for_each_set_bit(bit, &port, 8) {
887 /* scp3 ports start from 11 */
888 port_num = bit + 10;
889 sdw_handle_port_interrupt(slave,
890 port_num,
891 &port_status[port_num]);
892 }
893 }
894
895 /* Update the Slave driver */
896 if (slave_notify && (slave->ops) &&
897 (slave->ops->interrupt_callback)) {
898 slave_intr.control_port = clear;
899 memcpy(slave_intr.port, &port_status,
900 sizeof(slave_intr.port));
901
902 slave->ops->interrupt_callback(slave, &slave_intr);
903 }
904
905 /* Ack interrupt */
906 ret = sdw_write(slave, SDW_SCP_INT1, clear);
907 if (ret < 0) {
908 dev_err(slave->bus->dev,
909 "SDW_SCP_INT1 write failed:%d", ret);
910 return ret;
911 }
912
913 /*
914 * Read status again to ensure no new interrupts arrived
915 * while servicing interrupts.
916 */
917 _buf = ret = sdw_read(slave, SDW_SCP_INT1);
918 if (ret < 0) {
919 dev_err(slave->bus->dev,
920 "SDW_SCP_INT1 read failed:%d", ret);
921 return ret;
922 }
923
924 ret = sdw_nread(slave, SDW_SCP_INTSTAT2, 2, _buf2);
925 if (ret < 0) {
926 dev_err(slave->bus->dev,
927 "SDW_SCP_INT2/3 read failed:%d", ret);
928 return ret;
929 }
930
931 /* Make sure no interrupts are pending */
932 buf &= _buf;
933 buf2[0] &= _buf2[0];
934 buf2[1] &= _buf2[1];
935 stat = buf || buf2[0] || buf2[1];
936
937 /*
938 * Exit loop if Slave is continuously in ALERT state even
939 * after servicing the interrupt multiple times.
940 */
941 count++;
942
943 /* we can get alerts while processing so keep retrying */
944 } while (stat != 0 && count < SDW_READ_INTR_CLEAR_RETRY);
945
946 if (count == SDW_READ_INTR_CLEAR_RETRY)
947 dev_warn(slave->bus->dev, "Reached MAX_RETRY on alert read");
948
949 return ret;
950 }
951
952 static int sdw_update_slave_status(struct sdw_slave *slave,
953 enum sdw_slave_status status)
954 {
955 if ((slave->ops) && (slave->ops->update_status))
956 return slave->ops->update_status(slave, status);
957
958 return 0;
959 }
960
961 /**
962 * sdw_handle_slave_status() - Handle Slave status
963 * @bus: SDW bus instance
964 * @status: Status for all Slave(s)
965 */
966 int sdw_handle_slave_status(struct sdw_bus *bus,
967 enum sdw_slave_status status[])
968 {
969 enum sdw_slave_status prev_status;
970 struct sdw_slave *slave;
971 int i, ret = 0;
972
973 if (status[0] == SDW_SLAVE_ATTACHED) {
974 ret = sdw_program_device_num(bus);
975 if (ret)
976 dev_err(bus->dev, "Slave attach failed: %d", ret);
977 }
978
979 /* Continue to check other slave statuses */
980 for (i = 1; i <= SDW_MAX_DEVICES; i++) {
981 mutex_lock(&bus->bus_lock);
982 if (test_bit(i, bus->assigned) == false) {
983 mutex_unlock(&bus->bus_lock);
984 continue;
985 }
986 mutex_unlock(&bus->bus_lock);
987
988 slave = sdw_get_slave(bus, i);
989 if (!slave)
990 continue;
991
992 switch (status[i]) {
993 case SDW_SLAVE_UNATTACHED:
994 if (slave->status == SDW_SLAVE_UNATTACHED)
995 break;
996
997 sdw_modify_slave_status(slave, SDW_SLAVE_UNATTACHED);
998 break;
999
1000 case SDW_SLAVE_ALERT:
1001 ret = sdw_handle_slave_alerts(slave);
1002 if (ret)
1003 dev_err(bus->dev,
1004 "Slave %d alert handling failed: %d",
1005 i, ret);
1006 break;
1007
1008 case SDW_SLAVE_ATTACHED:
1009 if (slave->status == SDW_SLAVE_ATTACHED)
1010 break;
1011
1012 prev_status = slave->status;
1013 sdw_modify_slave_status(slave, SDW_SLAVE_ATTACHED);
1014
1015 if (prev_status == SDW_SLAVE_ALERT)
1016 break;
1017
1018 ret = sdw_initialize_slave(slave);
1019 if (ret)
1020 dev_err(bus->dev,
1021 "Slave %d initialization failed: %d",
1022 i, ret);
1023
1024 break;
1025
1026 default:
1027 dev_err(bus->dev, "Invalid slave %d status:%d",
1028 i, status[i]);
1029 break;
1030 }
1031
1032 ret = sdw_update_slave_status(slave, status[i]);
1033 if (ret)
1034 dev_err(slave->bus->dev,
1035 "Update Slave status failed:%d", ret);
1036
1037 }
1038
1039 return ret;
1040 }
1041 EXPORT_SYMBOL(sdw_handle_slave_status);
Linux with added FPC-III support