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treewide: remove redundant IS_ERR() before error code check
[linux/fpc-iii.git] / drivers / media / cec / cec-pin.c
blob660fe111f5409c87ada64fe7dc25be5b2c747ee1
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3 * Copyright 2017 Cisco Systems, Inc. and/or its affiliates. All rights reserved.
4 */
5
6 #include <linux/delay.h>
7 #include <linux/slab.h>
8 #include <linux/sched/types.h>
9
10 #include <media/cec-pin.h>
11 #include "cec-pin-priv.h"
12
13 /* All timings are in microseconds */
14
15 /* start bit timings */
16 #define CEC_TIM_START_BIT_LOW 3700
17 #define CEC_TIM_START_BIT_LOW_MIN 3500
18 #define CEC_TIM_START_BIT_LOW_MAX 3900
19 #define CEC_TIM_START_BIT_TOTAL 4500
20 #define CEC_TIM_START_BIT_TOTAL_MIN 4300
21 #define CEC_TIM_START_BIT_TOTAL_MAX 4700
22
23 /* data bit timings */
24 #define CEC_TIM_DATA_BIT_0_LOW 1500
25 #define CEC_TIM_DATA_BIT_0_LOW_MIN 1300
26 #define CEC_TIM_DATA_BIT_0_LOW_MAX 1700
27 #define CEC_TIM_DATA_BIT_1_LOW 600
28 #define CEC_TIM_DATA_BIT_1_LOW_MIN 400
29 #define CEC_TIM_DATA_BIT_1_LOW_MAX 800
30 #define CEC_TIM_DATA_BIT_TOTAL 2400
31 #define CEC_TIM_DATA_BIT_TOTAL_MIN 2050
32 #define CEC_TIM_DATA_BIT_TOTAL_MAX 2750
33 /* earliest safe time to sample the bit state */
34 #define CEC_TIM_DATA_BIT_SAMPLE 850
35 /* earliest time the bit is back to 1 (T7 + 50) */
36 #define CEC_TIM_DATA_BIT_HIGH 1750
37
38 /* when idle, sample once per millisecond */
39 #define CEC_TIM_IDLE_SAMPLE 1000
40 /* when processing the start bit, sample twice per millisecond */
41 #define CEC_TIM_START_BIT_SAMPLE 500
42 /* when polling for a state change, sample once every 50 microseconds */
43 #define CEC_TIM_SAMPLE 50
44
45 #define CEC_TIM_LOW_DRIVE_ERROR (1.5 * CEC_TIM_DATA_BIT_TOTAL)
46
47 /*
48 * Total data bit time that is too short/long for a valid bit,
49 * used for error injection.
50 */
51 #define CEC_TIM_DATA_BIT_TOTAL_SHORT 1800
52 #define CEC_TIM_DATA_BIT_TOTAL_LONG 2900
53
54 /*
55 * Total start bit time that is too short/long for a valid bit,
56 * used for error injection.
57 */
58 #define CEC_TIM_START_BIT_TOTAL_SHORT 4100
59 #define CEC_TIM_START_BIT_TOTAL_LONG 5000
60
61 /* Data bits are 0-7, EOM is bit 8 and ACK is bit 9 */
62 #define EOM_BIT 8
63 #define ACK_BIT 9
64
65 struct cec_state {
66 const char * const name;
67 unsigned int usecs;
68 };
69
70 static const struct cec_state states[CEC_PIN_STATES] = {
71 { "Off", 0 },
72 { "Idle", CEC_TIM_IDLE_SAMPLE },
73 { "Tx Wait", CEC_TIM_SAMPLE },
74 { "Tx Wait for High", CEC_TIM_IDLE_SAMPLE },
75 { "Tx Start Bit Low", CEC_TIM_START_BIT_LOW },
76 { "Tx Start Bit High", CEC_TIM_START_BIT_TOTAL - CEC_TIM_START_BIT_LOW },
77 { "Tx Start Bit High Short", CEC_TIM_START_BIT_TOTAL_SHORT - CEC_TIM_START_BIT_LOW },
78 { "Tx Start Bit High Long", CEC_TIM_START_BIT_TOTAL_LONG - CEC_TIM_START_BIT_LOW },
79 { "Tx Start Bit Low Custom", 0 },
80 { "Tx Start Bit High Custom", 0 },
81 { "Tx Data 0 Low", CEC_TIM_DATA_BIT_0_LOW },
82 { "Tx Data 0 High", CEC_TIM_DATA_BIT_TOTAL - CEC_TIM_DATA_BIT_0_LOW },
83 { "Tx Data 0 High Short", CEC_TIM_DATA_BIT_TOTAL_SHORT - CEC_TIM_DATA_BIT_0_LOW },
84 { "Tx Data 0 High Long", CEC_TIM_DATA_BIT_TOTAL_LONG - CEC_TIM_DATA_BIT_0_LOW },
85 { "Tx Data 1 Low", CEC_TIM_DATA_BIT_1_LOW },
86 { "Tx Data 1 High", CEC_TIM_DATA_BIT_TOTAL - CEC_TIM_DATA_BIT_1_LOW },
87 { "Tx Data 1 High Short", CEC_TIM_DATA_BIT_TOTAL_SHORT - CEC_TIM_DATA_BIT_1_LOW },
88 { "Tx Data 1 High Long", CEC_TIM_DATA_BIT_TOTAL_LONG - CEC_TIM_DATA_BIT_1_LOW },
89 { "Tx Data 1 High Pre Sample", CEC_TIM_DATA_BIT_SAMPLE - CEC_TIM_DATA_BIT_1_LOW },
90 { "Tx Data 1 High Post Sample", CEC_TIM_DATA_BIT_TOTAL - CEC_TIM_DATA_BIT_SAMPLE },
91 { "Tx Data 1 High Post Sample Short", CEC_TIM_DATA_BIT_TOTAL_SHORT - CEC_TIM_DATA_BIT_SAMPLE },
92 { "Tx Data 1 High Post Sample Long", CEC_TIM_DATA_BIT_TOTAL_LONG - CEC_TIM_DATA_BIT_SAMPLE },
93 { "Tx Data Bit Low Custom", 0 },
94 { "Tx Data Bit High Custom", 0 },
95 { "Tx Pulse Low Custom", 0 },
96 { "Tx Pulse High Custom", 0 },
97 { "Tx Low Drive", CEC_TIM_LOW_DRIVE_ERROR },
98 { "Rx Start Bit Low", CEC_TIM_SAMPLE },
99 { "Rx Start Bit High", CEC_TIM_SAMPLE },
100 { "Rx Data Sample", CEC_TIM_DATA_BIT_SAMPLE },
101 { "Rx Data Post Sample", CEC_TIM_DATA_BIT_HIGH - CEC_TIM_DATA_BIT_SAMPLE },
102 { "Rx Data Wait for Low", CEC_TIM_SAMPLE },
103 { "Rx Ack Low", CEC_TIM_DATA_BIT_0_LOW },
104 { "Rx Ack Low Post", CEC_TIM_DATA_BIT_HIGH - CEC_TIM_DATA_BIT_0_LOW },
105 { "Rx Ack High Post", CEC_TIM_DATA_BIT_HIGH },
106 { "Rx Ack Finish", CEC_TIM_DATA_BIT_TOTAL_MIN - CEC_TIM_DATA_BIT_HIGH },
107 { "Rx Low Drive", CEC_TIM_LOW_DRIVE_ERROR },
108 { "Rx Irq", 0 },
109 };
110
111 static void cec_pin_update(struct cec_pin *pin, bool v, bool force)
112 {
113 if (!force && v == pin->adap->cec_pin_is_high)
114 return;
115
116 pin->adap->cec_pin_is_high = v;
117 if (atomic_read(&pin->work_pin_num_events) < CEC_NUM_PIN_EVENTS) {
118 u8 ev = v;
119
120 if (pin->work_pin_events_dropped) {
121 pin->work_pin_events_dropped = false;
122 ev |= CEC_PIN_EVENT_FL_DROPPED;
123 }
124 pin->work_pin_events[pin->work_pin_events_wr] = ev;
125 pin->work_pin_ts[pin->work_pin_events_wr] = ktime_get();
126 pin->work_pin_events_wr =
127 (pin->work_pin_events_wr + 1) % CEC_NUM_PIN_EVENTS;
128 atomic_inc(&pin->work_pin_num_events);
129 } else {
130 pin->work_pin_events_dropped = true;
131 pin->work_pin_events_dropped_cnt++;
132 }
133 wake_up_interruptible(&pin->kthread_waitq);
134 }
135
136 static bool cec_pin_read(struct cec_pin *pin)
137 {
138 bool v = pin->ops->read(pin->adap);
139
140 cec_pin_update(pin, v, false);
141 return v;
142 }
143
144 static void cec_pin_low(struct cec_pin *pin)
145 {
146 pin->ops->low(pin->adap);
147 cec_pin_update(pin, false, false);
148 }
149
150 static bool cec_pin_high(struct cec_pin *pin)
151 {
152 pin->ops->high(pin->adap);
153 return cec_pin_read(pin);
154 }
155
156 static bool rx_error_inj(struct cec_pin *pin, unsigned int mode_offset,
157 int arg_idx, u8 *arg)
158 {
159 #ifdef CONFIG_CEC_PIN_ERROR_INJ
160 u16 cmd = cec_pin_rx_error_inj(pin);
161 u64 e = pin->error_inj[cmd];
162 unsigned int mode = (e >> mode_offset) & CEC_ERROR_INJ_MODE_MASK;
163
164 if (arg_idx >= 0) {
165 u8 pos = pin->error_inj_args[cmd][arg_idx];
166
167 if (arg)
168 *arg = pos;
169 else if (pos != pin->rx_bit)
170 return false;
171 }
172
173 switch (mode) {
174 case CEC_ERROR_INJ_MODE_ONCE:
175 pin->error_inj[cmd] &=
176 ~(CEC_ERROR_INJ_MODE_MASK << mode_offset);
177 return true;
178 case CEC_ERROR_INJ_MODE_ALWAYS:
179 return true;
180 case CEC_ERROR_INJ_MODE_TOGGLE:
181 return pin->rx_toggle;
182 default:
183 return false;
184 }
185 #else
186 return false;
187 #endif
188 }
189
190 static bool rx_nack(struct cec_pin *pin)
191 {
192 return rx_error_inj(pin, CEC_ERROR_INJ_RX_NACK_OFFSET, -1, NULL);
193 }
194
195 static bool rx_low_drive(struct cec_pin *pin)
196 {
197 return rx_error_inj(pin, CEC_ERROR_INJ_RX_LOW_DRIVE_OFFSET,
198 CEC_ERROR_INJ_RX_LOW_DRIVE_ARG_IDX, NULL);
199 }
200
201 static bool rx_add_byte(struct cec_pin *pin)
202 {
203 return rx_error_inj(pin, CEC_ERROR_INJ_RX_ADD_BYTE_OFFSET, -1, NULL);
204 }
205
206 static bool rx_remove_byte(struct cec_pin *pin)
207 {
208 return rx_error_inj(pin, CEC_ERROR_INJ_RX_REMOVE_BYTE_OFFSET, -1, NULL);
209 }
210
211 static bool rx_arb_lost(struct cec_pin *pin, u8 *poll)
212 {
213 return pin->tx_msg.len == 0 &&
214 rx_error_inj(pin, CEC_ERROR_INJ_RX_ARB_LOST_OFFSET,
215 CEC_ERROR_INJ_RX_ARB_LOST_ARG_IDX, poll);
216 }
217
218 static bool tx_error_inj(struct cec_pin *pin, unsigned int mode_offset,
219 int arg_idx, u8 *arg)
220 {
221 #ifdef CONFIG_CEC_PIN_ERROR_INJ
222 u16 cmd = cec_pin_tx_error_inj(pin);
223 u64 e = pin->error_inj[cmd];
224 unsigned int mode = (e >> mode_offset) & CEC_ERROR_INJ_MODE_MASK;
225
226 if (arg_idx >= 0) {
227 u8 pos = pin->error_inj_args[cmd][arg_idx];
228
229 if (arg)
230 *arg = pos;
231 else if (pos != pin->tx_bit)
232 return false;
233 }
234
235 switch (mode) {
236 case CEC_ERROR_INJ_MODE_ONCE:
237 pin->error_inj[cmd] &=
238 ~(CEC_ERROR_INJ_MODE_MASK << mode_offset);
239 return true;
240 case CEC_ERROR_INJ_MODE_ALWAYS:
241 return true;
242 case CEC_ERROR_INJ_MODE_TOGGLE:
243 return pin->tx_toggle;
244 default:
245 return false;
246 }
247 #else
248 return false;
249 #endif
250 }
251
252 static bool tx_no_eom(struct cec_pin *pin)
253 {
254 return tx_error_inj(pin, CEC_ERROR_INJ_TX_NO_EOM_OFFSET, -1, NULL);
255 }
256
257 static bool tx_early_eom(struct cec_pin *pin)
258 {
259 return tx_error_inj(pin, CEC_ERROR_INJ_TX_EARLY_EOM_OFFSET, -1, NULL);
260 }
261
262 static bool tx_short_bit(struct cec_pin *pin)
263 {
264 return tx_error_inj(pin, CEC_ERROR_INJ_TX_SHORT_BIT_OFFSET,
265 CEC_ERROR_INJ_TX_SHORT_BIT_ARG_IDX, NULL);
266 }
267
268 static bool tx_long_bit(struct cec_pin *pin)
269 {
270 return tx_error_inj(pin, CEC_ERROR_INJ_TX_LONG_BIT_OFFSET,
271 CEC_ERROR_INJ_TX_LONG_BIT_ARG_IDX, NULL);
272 }
273
274 static bool tx_custom_bit(struct cec_pin *pin)
275 {
276 return tx_error_inj(pin, CEC_ERROR_INJ_TX_CUSTOM_BIT_OFFSET,
277 CEC_ERROR_INJ_TX_CUSTOM_BIT_ARG_IDX, NULL);
278 }
279
280 static bool tx_short_start(struct cec_pin *pin)
281 {
282 return tx_error_inj(pin, CEC_ERROR_INJ_TX_SHORT_START_OFFSET, -1, NULL);
283 }
284
285 static bool tx_long_start(struct cec_pin *pin)
286 {
287 return tx_error_inj(pin, CEC_ERROR_INJ_TX_LONG_START_OFFSET, -1, NULL);
288 }
289
290 static bool tx_custom_start(struct cec_pin *pin)
291 {
292 return tx_error_inj(pin, CEC_ERROR_INJ_TX_CUSTOM_START_OFFSET,
293 -1, NULL);
294 }
295
296 static bool tx_last_bit(struct cec_pin *pin)
297 {
298 return tx_error_inj(pin, CEC_ERROR_INJ_TX_LAST_BIT_OFFSET,
299 CEC_ERROR_INJ_TX_LAST_BIT_ARG_IDX, NULL);
300 }
301
302 static u8 tx_add_bytes(struct cec_pin *pin)
303 {
304 u8 bytes;
305
306 if (tx_error_inj(pin, CEC_ERROR_INJ_TX_ADD_BYTES_OFFSET,
307 CEC_ERROR_INJ_TX_ADD_BYTES_ARG_IDX, &bytes))
308 return bytes;
309 return 0;
310 }
311
312 static bool tx_remove_byte(struct cec_pin *pin)
313 {
314 return tx_error_inj(pin, CEC_ERROR_INJ_TX_REMOVE_BYTE_OFFSET, -1, NULL);
315 }
316
317 static bool tx_low_drive(struct cec_pin *pin)
318 {
319 return tx_error_inj(pin, CEC_ERROR_INJ_TX_LOW_DRIVE_OFFSET,
320 CEC_ERROR_INJ_TX_LOW_DRIVE_ARG_IDX, NULL);
321 }
322
323 static void cec_pin_to_idle(struct cec_pin *pin)
324 {
325 /*
326 * Reset all status fields, release the bus and
327 * go to idle state.
328 */
329 pin->rx_bit = pin->tx_bit = 0;
330 pin->rx_msg.len = 0;
331 memset(pin->rx_msg.msg, 0, sizeof(pin->rx_msg.msg));
332 pin->ts = ns_to_ktime(0);
333 pin->tx_generated_poll = false;
334 pin->tx_post_eom = false;
335 if (pin->state >= CEC_ST_TX_WAIT &&
336 pin->state <= CEC_ST_TX_LOW_DRIVE)
337 pin->tx_toggle ^= 1;
338 if (pin->state >= CEC_ST_RX_START_BIT_LOW &&
339 pin->state <= CEC_ST_RX_LOW_DRIVE)
340 pin->rx_toggle ^= 1;
341 pin->state = CEC_ST_IDLE;
342 }
343
344 /*
345 * Handle Transmit-related states
346 *
347 * Basic state changes when transmitting:
348 *
349 * Idle -> Tx Wait (waiting for the end of signal free time) ->
350 * Tx Start Bit Low -> Tx Start Bit High ->
351 *
352 * Regular data bits + EOM:
353 * Tx Data 0 Low -> Tx Data 0 High ->
354 * or:
355 * Tx Data 1 Low -> Tx Data 1 High ->
356 *
357 * First 4 data bits or Ack bit:
358 * Tx Data 0 Low -> Tx Data 0 High ->
359 * or:
360 * Tx Data 1 Low -> Tx Data 1 High -> Tx Data 1 Pre Sample ->
361 * Tx Data 1 Post Sample ->
362 *
363 * After the last Ack go to Idle.
364 *
365 * If it detects a Low Drive condition then:
366 * Tx Wait For High -> Idle
367 *
368 * If it loses arbitration, then it switches to state Rx Data Post Sample.
369 */
370 static void cec_pin_tx_states(struct cec_pin *pin, ktime_t ts)
371 {
372 bool v;
373 bool is_ack_bit, ack;
374
375 switch (pin->state) {
376 case CEC_ST_TX_WAIT_FOR_HIGH:
377 if (cec_pin_read(pin))
378 cec_pin_to_idle(pin);
379 break;
380
381 case CEC_ST_TX_START_BIT_LOW:
382 if (tx_short_start(pin)) {
383 /*
384 * Error Injection: send an invalid (too short)
385 * start pulse.
386 */
387 pin->state = CEC_ST_TX_START_BIT_HIGH_SHORT;
388 } else if (tx_long_start(pin)) {
389 /*
390 * Error Injection: send an invalid (too long)
391 * start pulse.
392 */
393 pin->state = CEC_ST_TX_START_BIT_HIGH_LONG;
394 } else {
395 pin->state = CEC_ST_TX_START_BIT_HIGH;
396 }
397 /* Generate start bit */
398 cec_pin_high(pin);
399 break;
400
401 case CEC_ST_TX_START_BIT_LOW_CUSTOM:
402 pin->state = CEC_ST_TX_START_BIT_HIGH_CUSTOM;
403 /* Generate start bit */
404 cec_pin_high(pin);
405 break;
406
407 case CEC_ST_TX_DATA_BIT_1_HIGH_POST_SAMPLE:
408 case CEC_ST_TX_DATA_BIT_1_HIGH_POST_SAMPLE_SHORT:
409 case CEC_ST_TX_DATA_BIT_1_HIGH_POST_SAMPLE_LONG:
410 if (pin->tx_nacked) {
411 cec_pin_to_idle(pin);
412 pin->tx_msg.len = 0;
413 if (pin->tx_generated_poll)
414 break;
415 pin->work_tx_ts = ts;
416 pin->work_tx_status = CEC_TX_STATUS_NACK;
417 wake_up_interruptible(&pin->kthread_waitq);
418 break;
419 }
420 /* fall through */
421 case CEC_ST_TX_DATA_BIT_0_HIGH:
422 case CEC_ST_TX_DATA_BIT_0_HIGH_SHORT:
423 case CEC_ST_TX_DATA_BIT_0_HIGH_LONG:
424 case CEC_ST_TX_DATA_BIT_1_HIGH:
425 case CEC_ST_TX_DATA_BIT_1_HIGH_SHORT:
426 case CEC_ST_TX_DATA_BIT_1_HIGH_LONG:
427 /*
428 * If the read value is 1, then all is OK, otherwise we have a
429 * low drive condition.
430 *
431 * Special case: when we generate a poll message due to an
432 * Arbitration Lost error injection, then ignore this since
433 * the pin can actually be low in that case.
434 */
435 if (!cec_pin_read(pin) && !pin->tx_generated_poll) {
436 /*
437 * It's 0, so someone detected an error and pulled the
438 * line low for 1.5 times the nominal bit period.
439 */
440 pin->tx_msg.len = 0;
441 pin->state = CEC_ST_TX_WAIT_FOR_HIGH;
442 pin->work_tx_ts = ts;
443 pin->work_tx_status = CEC_TX_STATUS_LOW_DRIVE;
444 pin->tx_low_drive_cnt++;
445 wake_up_interruptible(&pin->kthread_waitq);
446 break;
447 }
448 /* fall through */
449 case CEC_ST_TX_DATA_BIT_HIGH_CUSTOM:
450 if (tx_last_bit(pin)) {
451 /* Error Injection: just stop sending after this bit */
452 cec_pin_to_idle(pin);
453 pin->tx_msg.len = 0;
454 if (pin->tx_generated_poll)
455 break;
456 pin->work_tx_ts = ts;
457 pin->work_tx_status = CEC_TX_STATUS_OK;
458 wake_up_interruptible(&pin->kthread_waitq);
459 break;
460 }
461 pin->tx_bit++;
462 /* fall through */
463 case CEC_ST_TX_START_BIT_HIGH:
464 case CEC_ST_TX_START_BIT_HIGH_SHORT:
465 case CEC_ST_TX_START_BIT_HIGH_LONG:
466 case CEC_ST_TX_START_BIT_HIGH_CUSTOM:
467 if (tx_low_drive(pin)) {
468 /* Error injection: go to low drive */
469 cec_pin_low(pin);
470 pin->state = CEC_ST_TX_LOW_DRIVE;
471 pin->tx_msg.len = 0;
472 if (pin->tx_generated_poll)
473 break;
474 pin->work_tx_ts = ts;
475 pin->work_tx_status = CEC_TX_STATUS_LOW_DRIVE;
476 pin->tx_low_drive_cnt++;
477 wake_up_interruptible(&pin->kthread_waitq);
478 break;
479 }
480 if (pin->tx_bit / 10 >= pin->tx_msg.len + pin->tx_extra_bytes) {
481 cec_pin_to_idle(pin);
482 pin->tx_msg.len = 0;
483 if (pin->tx_generated_poll)
484 break;
485 pin->work_tx_ts = ts;
486 pin->work_tx_status = CEC_TX_STATUS_OK;
487 wake_up_interruptible(&pin->kthread_waitq);
488 break;
489 }
490
491 switch (pin->tx_bit % 10) {
492 default: {
493 /*
494 * In the CEC_ERROR_INJ_TX_ADD_BYTES case we transmit
495 * extra bytes, so pin->tx_bit / 10 can become >= 16.
496 * Generate bit values for those extra bytes instead
497 * of reading them from the transmit buffer.
498 */
499 unsigned int idx = (pin->tx_bit / 10);
500 u8 val = idx;
501
502 if (idx < pin->tx_msg.len)
503 val = pin->tx_msg.msg[idx];
504 v = val & (1 << (7 - (pin->tx_bit % 10)));
505
506 pin->state = v ? CEC_ST_TX_DATA_BIT_1_LOW :
507 CEC_ST_TX_DATA_BIT_0_LOW;
508 break;
509 }
510 case EOM_BIT: {
511 unsigned int tot_len = pin->tx_msg.len +
512 pin->tx_extra_bytes;
513 unsigned int tx_byte_idx = pin->tx_bit / 10;
514
515 v = !pin->tx_post_eom && tx_byte_idx == tot_len - 1;
516 if (tot_len > 1 && tx_byte_idx == tot_len - 2 &&
517 tx_early_eom(pin)) {
518 /* Error injection: set EOM one byte early */
519 v = true;
520 pin->tx_post_eom = true;
521 } else if (v && tx_no_eom(pin)) {
522 /* Error injection: no EOM */
523 v = false;
524 }
525 pin->state = v ? CEC_ST_TX_DATA_BIT_1_LOW :
526 CEC_ST_TX_DATA_BIT_0_LOW;
527 break;
528 }
529 case ACK_BIT:
530 pin->state = CEC_ST_TX_DATA_BIT_1_LOW;
531 break;
532 }
533 if (tx_custom_bit(pin))
534 pin->state = CEC_ST_TX_DATA_BIT_LOW_CUSTOM;
535 cec_pin_low(pin);
536 break;
537
538 case CEC_ST_TX_DATA_BIT_0_LOW:
539 case CEC_ST_TX_DATA_BIT_1_LOW:
540 v = pin->state == CEC_ST_TX_DATA_BIT_1_LOW;
541 is_ack_bit = pin->tx_bit % 10 == ACK_BIT;
542 if (v && (pin->tx_bit < 4 || is_ack_bit)) {
543 pin->state = CEC_ST_TX_DATA_BIT_1_HIGH_PRE_SAMPLE;
544 } else if (!is_ack_bit && tx_short_bit(pin)) {
545 /* Error Injection: send an invalid (too short) bit */
546 pin->state = v ? CEC_ST_TX_DATA_BIT_1_HIGH_SHORT :
547 CEC_ST_TX_DATA_BIT_0_HIGH_SHORT;
548 } else if (!is_ack_bit && tx_long_bit(pin)) {
549 /* Error Injection: send an invalid (too long) bit */
550 pin->state = v ? CEC_ST_TX_DATA_BIT_1_HIGH_LONG :
551 CEC_ST_TX_DATA_BIT_0_HIGH_LONG;
552 } else {
553 pin->state = v ? CEC_ST_TX_DATA_BIT_1_HIGH :
554 CEC_ST_TX_DATA_BIT_0_HIGH;
555 }
556 cec_pin_high(pin);
557 break;
558
559 case CEC_ST_TX_DATA_BIT_LOW_CUSTOM:
560 pin->state = CEC_ST_TX_DATA_BIT_HIGH_CUSTOM;
561 cec_pin_high(pin);
562 break;
563
564 case CEC_ST_TX_DATA_BIT_1_HIGH_PRE_SAMPLE:
565 /* Read the CEC value at the sample time */
566 v = cec_pin_read(pin);
567 is_ack_bit = pin->tx_bit % 10 == ACK_BIT;
568 /*
569 * If v == 0 and we're within the first 4 bits
570 * of the initiator, then someone else started
571 * transmitting and we lost the arbitration
572 * (i.e. the logical address of the other
573 * transmitter has more leading 0 bits in the
574 * initiator).
575 */
576 if (!v && !is_ack_bit && !pin->tx_generated_poll) {
577 pin->tx_msg.len = 0;
578 pin->work_tx_ts = ts;
579 pin->work_tx_status = CEC_TX_STATUS_ARB_LOST;
580 wake_up_interruptible(&pin->kthread_waitq);
581 pin->rx_bit = pin->tx_bit;
582 pin->tx_bit = 0;
583 memset(pin->rx_msg.msg, 0, sizeof(pin->rx_msg.msg));
584 pin->rx_msg.msg[0] = pin->tx_msg.msg[0];
585 pin->rx_msg.msg[0] &= (0xff << (8 - pin->rx_bit));
586 pin->rx_msg.len = 0;
587 pin->ts = ktime_sub_us(ts, CEC_TIM_DATA_BIT_SAMPLE);
588 pin->state = CEC_ST_RX_DATA_POST_SAMPLE;
589 pin->rx_bit++;
590 break;
591 }
592 pin->state = CEC_ST_TX_DATA_BIT_1_HIGH_POST_SAMPLE;
593 if (!is_ack_bit && tx_short_bit(pin)) {
594 /* Error Injection: send an invalid (too short) bit */
595 pin->state = CEC_ST_TX_DATA_BIT_1_HIGH_POST_SAMPLE_SHORT;
596 } else if (!is_ack_bit && tx_long_bit(pin)) {
597 /* Error Injection: send an invalid (too long) bit */
598 pin->state = CEC_ST_TX_DATA_BIT_1_HIGH_POST_SAMPLE_LONG;
599 }
600 if (!is_ack_bit)
601 break;
602 /* Was the message ACKed? */
603 ack = cec_msg_is_broadcast(&pin->tx_msg) ? v : !v;
604 if (!ack && (!pin->tx_ignore_nack_until_eom ||
605 pin->tx_bit / 10 == pin->tx_msg.len - 1) &&
606 !pin->tx_post_eom) {
607 /*
608 * Note: the CEC spec is ambiguous regarding
609 * what action to take when a NACK appears
610 * before the last byte of the payload was
611 * transmitted: either stop transmitting
612 * immediately, or wait until the last byte
613 * was transmitted.
614 *
615 * Most CEC implementations appear to stop
616 * immediately, and that's what we do here
617 * as well.
618 */
619 pin->tx_nacked = true;
620 }
621 break;
622
623 case CEC_ST_TX_PULSE_LOW_CUSTOM:
624 cec_pin_high(pin);
625 pin->state = CEC_ST_TX_PULSE_HIGH_CUSTOM;
626 break;
627
628 case CEC_ST_TX_PULSE_HIGH_CUSTOM:
629 cec_pin_to_idle(pin);
630 break;
631
632 default:
633 break;
634 }
635 }
636
637 /*
638 * Handle Receive-related states
639 *
640 * Basic state changes when receiving:
641 *
642 * Rx Start Bit Low -> Rx Start Bit High ->
643 * Regular data bits + EOM:
644 * Rx Data Sample -> Rx Data Post Sample -> Rx Data High ->
645 * Ack bit 0:
646 * Rx Ack Low -> Rx Ack Low Post -> Rx Data High ->
647 * Ack bit 1:
648 * Rx Ack High Post -> Rx Data High ->
649 * Ack bit 0 && EOM:
650 * Rx Ack Low -> Rx Ack Low Post -> Rx Ack Finish -> Idle
651 */
652 static void cec_pin_rx_states(struct cec_pin *pin, ktime_t ts)
653 {
654 s32 delta;
655 bool v;
656 bool ack;
657 bool bcast, for_us;
658 u8 dest;
659 u8 poll;
660
661 switch (pin->state) {
662 /* Receive states */
663 case CEC_ST_RX_START_BIT_LOW:
664 v = cec_pin_read(pin);
665 if (!v)
666 break;
667 pin->state = CEC_ST_RX_START_BIT_HIGH;
668 delta = ktime_us_delta(ts, pin->ts);
669 /* Start bit low is too short, go back to idle */
670 if (delta < CEC_TIM_START_BIT_LOW_MIN - CEC_TIM_IDLE_SAMPLE) {
671 if (!pin->rx_start_bit_low_too_short_cnt++) {
672 pin->rx_start_bit_low_too_short_ts = ktime_to_ns(pin->ts);
673 pin->rx_start_bit_low_too_short_delta = delta;
674 }
675 cec_pin_to_idle(pin);
676 break;
677 }
678 if (rx_arb_lost(pin, &poll)) {
679 cec_msg_init(&pin->tx_msg, poll >> 4, poll & 0xf);
680 pin->tx_generated_poll = true;
681 pin->tx_extra_bytes = 0;
682 pin->state = CEC_ST_TX_START_BIT_HIGH;
683 pin->ts = ts;
684 }
685 break;
686
687 case CEC_ST_RX_START_BIT_HIGH:
688 v = cec_pin_read(pin);
689 delta = ktime_us_delta(ts, pin->ts);
690 /*
691 * Unfortunately the spec does not specify when to give up
692 * and go to idle. We just pick TOTAL_LONG.
693 */
694 if (v && delta > CEC_TIM_START_BIT_TOTAL_LONG) {
695 pin->rx_start_bit_too_long_cnt++;
696 cec_pin_to_idle(pin);
697 break;
698 }
699 if (v)
700 break;
701 /* Start bit is too short, go back to idle */
702 if (delta < CEC_TIM_START_BIT_TOTAL_MIN - CEC_TIM_IDLE_SAMPLE) {
703 if (!pin->rx_start_bit_too_short_cnt++) {
704 pin->rx_start_bit_too_short_ts = ktime_to_ns(pin->ts);
705 pin->rx_start_bit_too_short_delta = delta;
706 }
707 cec_pin_to_idle(pin);
708 break;
709 }
710 if (rx_low_drive(pin)) {
711 /* Error injection: go to low drive */
712 cec_pin_low(pin);
713 pin->state = CEC_ST_RX_LOW_DRIVE;
714 pin->rx_low_drive_cnt++;
715 break;
716 }
717 pin->state = CEC_ST_RX_DATA_SAMPLE;
718 pin->ts = ts;
719 pin->rx_eom = false;
720 break;
721
722 case CEC_ST_RX_DATA_SAMPLE:
723 v = cec_pin_read(pin);
724 pin->state = CEC_ST_RX_DATA_POST_SAMPLE;
725 switch (pin->rx_bit % 10) {
726 default:
727 if (pin->rx_bit / 10 < CEC_MAX_MSG_SIZE)
728 pin->rx_msg.msg[pin->rx_bit / 10] |=
729 v << (7 - (pin->rx_bit % 10));
730 break;
731 case EOM_BIT:
732 pin->rx_eom = v;
733 pin->rx_msg.len = pin->rx_bit / 10 + 1;
734 break;
735 case ACK_BIT:
736 break;
737 }
738 pin->rx_bit++;
739 break;
740
741 case CEC_ST_RX_DATA_POST_SAMPLE:
742 pin->state = CEC_ST_RX_DATA_WAIT_FOR_LOW;
743 break;
744
745 case CEC_ST_RX_DATA_WAIT_FOR_LOW:
746 v = cec_pin_read(pin);
747 delta = ktime_us_delta(ts, pin->ts);
748 /*
749 * Unfortunately the spec does not specify when to give up
750 * and go to idle. We just pick TOTAL_LONG.
751 */
752 if (v && delta > CEC_TIM_DATA_BIT_TOTAL_LONG) {
753 pin->rx_data_bit_too_long_cnt++;
754 cec_pin_to_idle(pin);
755 break;
756 }
757 if (v)
758 break;
759
760 if (rx_low_drive(pin)) {
761 /* Error injection: go to low drive */
762 cec_pin_low(pin);
763 pin->state = CEC_ST_RX_LOW_DRIVE;
764 pin->rx_low_drive_cnt++;
765 break;
766 }
767
768 /*
769 * Go to low drive state when the total bit time is
770 * too short.
771 */
772 if (delta < CEC_TIM_DATA_BIT_TOTAL_MIN) {
773 if (!pin->rx_data_bit_too_short_cnt++) {
774 pin->rx_data_bit_too_short_ts = ktime_to_ns(pin->ts);
775 pin->rx_data_bit_too_short_delta = delta;
776 }
777 cec_pin_low(pin);
778 pin->state = CEC_ST_RX_LOW_DRIVE;
779 pin->rx_low_drive_cnt++;
780 break;
781 }
782 pin->ts = ts;
783 if (pin->rx_bit % 10 != 9) {
784 pin->state = CEC_ST_RX_DATA_SAMPLE;
785 break;
786 }
787
788 dest = cec_msg_destination(&pin->rx_msg);
789 bcast = dest == CEC_LOG_ADDR_BROADCAST;
790 /* for_us == broadcast or directed to us */
791 for_us = bcast || (pin->la_mask & (1 << dest));
792 /* ACK bit value */
793 ack = bcast ? 1 : !for_us;
794
795 if (for_us && rx_nack(pin)) {
796 /* Error injection: toggle the ACK bit */
797 ack = !ack;
798 }
799
800 if (ack) {
801 /* No need to write to the bus, just wait */
802 pin->state = CEC_ST_RX_ACK_HIGH_POST;
803 break;
804 }
805 cec_pin_low(pin);
806 pin->state = CEC_ST_RX_ACK_LOW;
807 break;
808
809 case CEC_ST_RX_ACK_LOW:
810 cec_pin_high(pin);
811 pin->state = CEC_ST_RX_ACK_LOW_POST;
812 break;
813
814 case CEC_ST_RX_ACK_LOW_POST:
815 case CEC_ST_RX_ACK_HIGH_POST:
816 v = cec_pin_read(pin);
817 if (v && pin->rx_eom) {
818 pin->work_rx_msg = pin->rx_msg;
819 pin->work_rx_msg.rx_ts = ktime_to_ns(ts);
820 wake_up_interruptible(&pin->kthread_waitq);
821 pin->ts = ts;
822 pin->state = CEC_ST_RX_ACK_FINISH;
823 break;
824 }
825 pin->rx_bit++;
826 pin->state = CEC_ST_RX_DATA_WAIT_FOR_LOW;
827 break;
828
829 case CEC_ST_RX_ACK_FINISH:
830 cec_pin_to_idle(pin);
831 break;
832
833 default:
834 break;
835 }
836 }
837
838 /*
839 * Main timer function
840 *
841 */
842 static enum hrtimer_restart cec_pin_timer(struct hrtimer *timer)
843 {
844 struct cec_pin *pin = container_of(timer, struct cec_pin, timer);
845 struct cec_adapter *adap = pin->adap;
846 ktime_t ts;
847 s32 delta;
848 u32 usecs;
849
850 ts = ktime_get();
851 if (ktime_to_ns(pin->timer_ts)) {
852 delta = ktime_us_delta(ts, pin->timer_ts);
853 pin->timer_cnt++;
854 if (delta > 100 && pin->state != CEC_ST_IDLE) {
855 /* Keep track of timer overruns */
856 pin->timer_sum_overrun += delta;
857 pin->timer_100ms_overruns++;
858 if (delta > 300)
859 pin->timer_300ms_overruns++;
860 if (delta > pin->timer_max_overrun)
861 pin->timer_max_overrun = delta;
862 }
863 }
864 if (adap->monitor_pin_cnt)
865 cec_pin_read(pin);
866
867 if (pin->wait_usecs) {
868 /*
869 * If we are monitoring the pin, then we have to
870 * sample at regular intervals.
871 */
872 if (pin->wait_usecs > 150) {
873 pin->wait_usecs -= 100;
874 pin->timer_ts = ktime_add_us(ts, 100);
875 hrtimer_forward_now(timer, ns_to_ktime(100000));
876 return HRTIMER_RESTART;
877 }
878 if (pin->wait_usecs > 100) {
879 pin->wait_usecs /= 2;
880 pin->timer_ts = ktime_add_us(ts, pin->wait_usecs);
881 hrtimer_forward_now(timer,
882 ns_to_ktime(pin->wait_usecs * 1000));
883 return HRTIMER_RESTART;
884 }
885 pin->timer_ts = ktime_add_us(ts, pin->wait_usecs);
886 hrtimer_forward_now(timer,
887 ns_to_ktime(pin->wait_usecs * 1000));
888 pin->wait_usecs = 0;
889 return HRTIMER_RESTART;
890 }
891
892 switch (pin->state) {
893 /* Transmit states */
894 case CEC_ST_TX_WAIT_FOR_HIGH:
895 case CEC_ST_TX_START_BIT_LOW:
896 case CEC_ST_TX_START_BIT_HIGH:
897 case CEC_ST_TX_START_BIT_HIGH_SHORT:
898 case CEC_ST_TX_START_BIT_HIGH_LONG:
899 case CEC_ST_TX_START_BIT_LOW_CUSTOM:
900 case CEC_ST_TX_START_BIT_HIGH_CUSTOM:
901 case CEC_ST_TX_DATA_BIT_0_LOW:
902 case CEC_ST_TX_DATA_BIT_0_HIGH:
903 case CEC_ST_TX_DATA_BIT_0_HIGH_SHORT:
904 case CEC_ST_TX_DATA_BIT_0_HIGH_LONG:
905 case CEC_ST_TX_DATA_BIT_1_LOW:
906 case CEC_ST_TX_DATA_BIT_1_HIGH:
907 case CEC_ST_TX_DATA_BIT_1_HIGH_SHORT:
908 case CEC_ST_TX_DATA_BIT_1_HIGH_LONG:
909 case CEC_ST_TX_DATA_BIT_1_HIGH_PRE_SAMPLE:
910 case CEC_ST_TX_DATA_BIT_1_HIGH_POST_SAMPLE:
911 case CEC_ST_TX_DATA_BIT_1_HIGH_POST_SAMPLE_SHORT:
912 case CEC_ST_TX_DATA_BIT_1_HIGH_POST_SAMPLE_LONG:
913 case CEC_ST_TX_DATA_BIT_LOW_CUSTOM:
914 case CEC_ST_TX_DATA_BIT_HIGH_CUSTOM:
915 case CEC_ST_TX_PULSE_LOW_CUSTOM:
916 case CEC_ST_TX_PULSE_HIGH_CUSTOM:
917 cec_pin_tx_states(pin, ts);
918 break;
919
920 /* Receive states */
921 case CEC_ST_RX_START_BIT_LOW:
922 case CEC_ST_RX_START_BIT_HIGH:
923 case CEC_ST_RX_DATA_SAMPLE:
924 case CEC_ST_RX_DATA_POST_SAMPLE:
925 case CEC_ST_RX_DATA_WAIT_FOR_LOW:
926 case CEC_ST_RX_ACK_LOW:
927 case CEC_ST_RX_ACK_LOW_POST:
928 case CEC_ST_RX_ACK_HIGH_POST:
929 case CEC_ST_RX_ACK_FINISH:
930 cec_pin_rx_states(pin, ts);
931 break;
932
933 case CEC_ST_IDLE:
934 case CEC_ST_TX_WAIT:
935 if (!cec_pin_high(pin)) {
936 /* Start bit, switch to receive state */
937 pin->ts = ts;
938 pin->state = CEC_ST_RX_START_BIT_LOW;
939 /*
940 * If a transmit is pending, then that transmit should
941 * use a signal free time of no more than
942 * CEC_SIGNAL_FREE_TIME_NEW_INITIATOR since it will
943 * have a new initiator due to the receive that is now
944 * starting.
945 */
946 if (pin->tx_msg.len && pin->tx_signal_free_time >
947 CEC_SIGNAL_FREE_TIME_NEW_INITIATOR)
948 pin->tx_signal_free_time =
949 CEC_SIGNAL_FREE_TIME_NEW_INITIATOR;
950 break;
951 }
952 if (ktime_to_ns(pin->ts) == 0)
953 pin->ts = ts;
954 if (pin->tx_msg.len) {
955 /*
956 * Check if the bus has been free for long enough
957 * so we can kick off the pending transmit.
958 */
959 delta = ktime_us_delta(ts, pin->ts);
960 if (delta / CEC_TIM_DATA_BIT_TOTAL >
961 pin->tx_signal_free_time) {
962 pin->tx_nacked = false;
963 if (tx_custom_start(pin))
964 pin->state = CEC_ST_TX_START_BIT_LOW_CUSTOM;
965 else
966 pin->state = CEC_ST_TX_START_BIT_LOW;
967 /* Generate start bit */
968 cec_pin_low(pin);
969 break;
970 }
971 if (delta / CEC_TIM_DATA_BIT_TOTAL >
972 pin->tx_signal_free_time - 1)
973 pin->state = CEC_ST_TX_WAIT;
974 break;
975 }
976 if (pin->tx_custom_pulse && pin->state == CEC_ST_IDLE) {
977 pin->tx_custom_pulse = false;
978 /* Generate custom pulse */
979 cec_pin_low(pin);
980 pin->state = CEC_ST_TX_PULSE_LOW_CUSTOM;
981 break;
982 }
983 if (pin->state != CEC_ST_IDLE || pin->ops->enable_irq == NULL ||
984 pin->enable_irq_failed || adap->is_configuring ||
985 adap->is_configured || adap->monitor_all_cnt)
986 break;
987 /* Switch to interrupt mode */
988 atomic_set(&pin->work_irq_change, CEC_PIN_IRQ_ENABLE);
989 pin->state = CEC_ST_RX_IRQ;
990 wake_up_interruptible(&pin->kthread_waitq);
991 return HRTIMER_NORESTART;
992
993 case CEC_ST_TX_LOW_DRIVE:
994 case CEC_ST_RX_LOW_DRIVE:
995 cec_pin_high(pin);
996 cec_pin_to_idle(pin);
997 break;
998
999 default:
1000 break;
1001 }
1002
1003 switch (pin->state) {
1004 case CEC_ST_TX_START_BIT_LOW_CUSTOM:
1005 case CEC_ST_TX_DATA_BIT_LOW_CUSTOM:
1006 case CEC_ST_TX_PULSE_LOW_CUSTOM:
1007 usecs = pin->tx_custom_low_usecs;
1008 break;
1009 case CEC_ST_TX_START_BIT_HIGH_CUSTOM:
1010 case CEC_ST_TX_DATA_BIT_HIGH_CUSTOM:
1011 case CEC_ST_TX_PULSE_HIGH_CUSTOM:
1012 usecs = pin->tx_custom_high_usecs;
1013 break;
1014 default:
1015 usecs = states[pin->state].usecs;
1016 break;
1017 }
1018
1019 if (!adap->monitor_pin_cnt || usecs <= 150) {
1020 pin->wait_usecs = 0;
1021 pin->timer_ts = ktime_add_us(ts, usecs);
1022 hrtimer_forward_now(timer,
1023 ns_to_ktime(usecs * 1000));
1024 return HRTIMER_RESTART;
1025 }
1026 pin->wait_usecs = usecs - 100;
1027 pin->timer_ts = ktime_add_us(ts, 100);
1028 hrtimer_forward_now(timer, ns_to_ktime(100000));
1029 return HRTIMER_RESTART;
1030 }
1031
1032 static int cec_pin_thread_func(void *_adap)
1033 {
1034 struct cec_adapter *adap = _adap;
1035 struct cec_pin *pin = adap->pin;
1036
1037 for (;;) {
1038 wait_event_interruptible(pin->kthread_waitq,
1039 kthread_should_stop() ||
1040 pin->work_rx_msg.len ||
1041 pin->work_tx_status ||
1042 atomic_read(&pin->work_irq_change) ||
1043 atomic_read(&pin->work_pin_num_events));
1044
1045 if (pin->work_rx_msg.len) {
1046 struct cec_msg *msg = &pin->work_rx_msg;
1047
1048 if (msg->len > 1 && msg->len < CEC_MAX_MSG_SIZE &&
1049 rx_add_byte(pin)) {
1050 /* Error injection: add byte to the message */
1051 msg->msg[msg->len++] = 0x55;
1052 }
1053 if (msg->len > 2 && rx_remove_byte(pin)) {
1054 /* Error injection: remove byte from message */
1055 msg->len--;
1056 }
1057 if (msg->len > CEC_MAX_MSG_SIZE)
1058 msg->len = CEC_MAX_MSG_SIZE;
1059 cec_received_msg_ts(adap, msg,
1060 ns_to_ktime(pin->work_rx_msg.rx_ts));
1061 msg->len = 0;
1062 }
1063 if (pin->work_tx_status) {
1064 unsigned int tx_status = pin->work_tx_status;
1065
1066 pin->work_tx_status = 0;
1067 cec_transmit_attempt_done_ts(adap, tx_status,
1068 pin->work_tx_ts);
1069 }
1070
1071 while (atomic_read(&pin->work_pin_num_events)) {
1072 unsigned int idx = pin->work_pin_events_rd;
1073 u8 v = pin->work_pin_events[idx];
1074
1075 cec_queue_pin_cec_event(adap,
1076 v & CEC_PIN_EVENT_FL_IS_HIGH,
1077 v & CEC_PIN_EVENT_FL_DROPPED,
1078 pin->work_pin_ts[idx]);
1079 pin->work_pin_events_rd = (idx + 1) % CEC_NUM_PIN_EVENTS;
1080 atomic_dec(&pin->work_pin_num_events);
1081 }
1082
1083 switch (atomic_xchg(&pin->work_irq_change,
1084 CEC_PIN_IRQ_UNCHANGED)) {
1085 case CEC_PIN_IRQ_DISABLE:
1086 pin->ops->disable_irq(adap);
1087 cec_pin_high(pin);
1088 cec_pin_to_idle(pin);
1089 hrtimer_start(&pin->timer, ns_to_ktime(0),
1090 HRTIMER_MODE_REL);
1091 break;
1092 case CEC_PIN_IRQ_ENABLE:
1093 pin->enable_irq_failed = !pin->ops->enable_irq(adap);
1094 if (pin->enable_irq_failed) {
1095 cec_pin_to_idle(pin);
1096 hrtimer_start(&pin->timer, ns_to_ktime(0),
1097 HRTIMER_MODE_REL);
1098 }
1099 break;
1100 default:
1101 break;
1102 }
1103
1104 if (kthread_should_stop())
1105 break;
1106 }
1107 return 0;
1108 }
1109
1110 static int cec_pin_adap_enable(struct cec_adapter *adap, bool enable)
1111 {
1112 struct cec_pin *pin = adap->pin;
1113
1114 pin->enabled = enable;
1115 if (enable) {
1116 atomic_set(&pin->work_pin_num_events, 0);
1117 pin->work_pin_events_rd = pin->work_pin_events_wr = 0;
1118 pin->work_pin_events_dropped = false;
1119 cec_pin_read(pin);
1120 cec_pin_to_idle(pin);
1121 pin->tx_msg.len = 0;
1122 pin->timer_ts = ns_to_ktime(0);
1123 atomic_set(&pin->work_irq_change, CEC_PIN_IRQ_UNCHANGED);
1124 pin->kthread = kthread_run(cec_pin_thread_func, adap,
1125 "cec-pin");
1126 if (IS_ERR(pin->kthread)) {
1127 pr_err("cec-pin: kernel_thread() failed\n");
1128 return PTR_ERR(pin->kthread);
1129 }
1130 hrtimer_start(&pin->timer, ns_to_ktime(0),
1131 HRTIMER_MODE_REL);
1132 } else {
1133 if (pin->ops->disable_irq)
1134 pin->ops->disable_irq(adap);
1135 hrtimer_cancel(&pin->timer);
1136 kthread_stop(pin->kthread);
1137 cec_pin_read(pin);
1138 cec_pin_to_idle(pin);
1139 pin->state = CEC_ST_OFF;
1140 }
1141 return 0;
1142 }
1143
1144 static int cec_pin_adap_log_addr(struct cec_adapter *adap, u8 log_addr)
1145 {
1146 struct cec_pin *pin = adap->pin;
1147
1148 if (log_addr == CEC_LOG_ADDR_INVALID)
1149 pin->la_mask = 0;
1150 else
1151 pin->la_mask |= (1 << log_addr);
1152 return 0;
1153 }
1154
1155 void cec_pin_start_timer(struct cec_pin *pin)
1156 {
1157 if (pin->state != CEC_ST_RX_IRQ)
1158 return;
1159
1160 atomic_set(&pin->work_irq_change, CEC_PIN_IRQ_UNCHANGED);
1161 pin->ops->disable_irq(pin->adap);
1162 cec_pin_high(pin);
1163 cec_pin_to_idle(pin);
1164 hrtimer_start(&pin->timer, ns_to_ktime(0), HRTIMER_MODE_REL);
1165 }
1166
1167 static int cec_pin_adap_transmit(struct cec_adapter *adap, u8 attempts,
1168 u32 signal_free_time, struct cec_msg *msg)
1169 {
1170 struct cec_pin *pin = adap->pin;
1171
1172 /*
1173 * If a receive is in progress, then this transmit should use
1174 * a signal free time of max CEC_SIGNAL_FREE_TIME_NEW_INITIATOR
1175 * since when it starts transmitting it will have a new initiator.
1176 */
1177 if (pin->state != CEC_ST_IDLE &&
1178 signal_free_time > CEC_SIGNAL_FREE_TIME_NEW_INITIATOR)
1179 signal_free_time = CEC_SIGNAL_FREE_TIME_NEW_INITIATOR;
1180
1181 pin->tx_signal_free_time = signal_free_time;
1182 pin->tx_extra_bytes = 0;
1183 pin->tx_msg = *msg;
1184 if (msg->len > 1) {
1185 /* Error injection: add byte to the message */
1186 pin->tx_extra_bytes = tx_add_bytes(pin);
1187 }
1188 if (msg->len > 2 && tx_remove_byte(pin)) {
1189 /* Error injection: remove byte from the message */
1190 pin->tx_msg.len--;
1191 }
1192 pin->work_tx_status = 0;
1193 pin->tx_bit = 0;
1194 cec_pin_start_timer(pin);
1195 return 0;
1196 }
1197
1198 static void cec_pin_adap_status(struct cec_adapter *adap,
1199 struct seq_file *file)
1200 {
1201 struct cec_pin *pin = adap->pin;
1202
1203 seq_printf(file, "state: %s\n", states[pin->state].name);
1204 seq_printf(file, "tx_bit: %d\n", pin->tx_bit);
1205 seq_printf(file, "rx_bit: %d\n", pin->rx_bit);
1206 seq_printf(file, "cec pin: %d\n", pin->ops->read(adap));
1207 seq_printf(file, "cec pin events dropped: %u\n",
1208 pin->work_pin_events_dropped_cnt);
1209 seq_printf(file, "irq failed: %d\n", pin->enable_irq_failed);
1210 if (pin->timer_100ms_overruns) {
1211 seq_printf(file, "timer overruns > 100ms: %u of %u\n",
1212 pin->timer_100ms_overruns, pin->timer_cnt);
1213 seq_printf(file, "timer overruns > 300ms: %u of %u\n",
1214 pin->timer_300ms_overruns, pin->timer_cnt);
1215 seq_printf(file, "max timer overrun: %u usecs\n",
1216 pin->timer_max_overrun);
1217 seq_printf(file, "avg timer overrun: %u usecs\n",
1218 pin->timer_sum_overrun / pin->timer_100ms_overruns);
1219 }
1220 if (pin->rx_start_bit_low_too_short_cnt)
1221 seq_printf(file,
1222 "rx start bit low too short: %u (delta %u, ts %llu)\n",
1223 pin->rx_start_bit_low_too_short_cnt,
1224 pin->rx_start_bit_low_too_short_delta,
1225 pin->rx_start_bit_low_too_short_ts);
1226 if (pin->rx_start_bit_too_short_cnt)
1227 seq_printf(file,
1228 "rx start bit too short: %u (delta %u, ts %llu)\n",
1229 pin->rx_start_bit_too_short_cnt,
1230 pin->rx_start_bit_too_short_delta,
1231 pin->rx_start_bit_too_short_ts);
1232 if (pin->rx_start_bit_too_long_cnt)
1233 seq_printf(file, "rx start bit too long: %u\n",
1234 pin->rx_start_bit_too_long_cnt);
1235 if (pin->rx_data_bit_too_short_cnt)
1236 seq_printf(file,
1237 "rx data bit too short: %u (delta %u, ts %llu)\n",
1238 pin->rx_data_bit_too_short_cnt,
1239 pin->rx_data_bit_too_short_delta,
1240 pin->rx_data_bit_too_short_ts);
1241 if (pin->rx_data_bit_too_long_cnt)
1242 seq_printf(file, "rx data bit too long: %u\n",
1243 pin->rx_data_bit_too_long_cnt);
1244 seq_printf(file, "rx initiated low drive: %u\n", pin->rx_low_drive_cnt);
1245 seq_printf(file, "tx detected low drive: %u\n", pin->tx_low_drive_cnt);
1246 pin->work_pin_events_dropped_cnt = 0;
1247 pin->timer_cnt = 0;
1248 pin->timer_100ms_overruns = 0;
1249 pin->timer_300ms_overruns = 0;
1250 pin->timer_max_overrun = 0;
1251 pin->timer_sum_overrun = 0;
1252 pin->rx_start_bit_low_too_short_cnt = 0;
1253 pin->rx_start_bit_too_short_cnt = 0;
1254 pin->rx_start_bit_too_long_cnt = 0;
1255 pin->rx_data_bit_too_short_cnt = 0;
1256 pin->rx_data_bit_too_long_cnt = 0;
1257 pin->rx_low_drive_cnt = 0;
1258 pin->tx_low_drive_cnt = 0;
1259 if (pin->ops->status)
1260 pin->ops->status(adap, file);
1261 }
1262
1263 static int cec_pin_adap_monitor_all_enable(struct cec_adapter *adap,
1264 bool enable)
1265 {
1266 struct cec_pin *pin = adap->pin;
1267
1268 pin->monitor_all = enable;
1269 return 0;
1270 }
1271
1272 static void cec_pin_adap_free(struct cec_adapter *adap)
1273 {
1274 struct cec_pin *pin = adap->pin;
1275
1276 if (pin->ops->free)
1277 pin->ops->free(adap);
1278 adap->pin = NULL;
1279 kfree(pin);
1280 }
1281
1282 static int cec_pin_received(struct cec_adapter *adap, struct cec_msg *msg)
1283 {
1284 struct cec_pin *pin = adap->pin;
1285
1286 if (pin->ops->received)
1287 return pin->ops->received(adap, msg);
1288 return -ENOMSG;
1289 }
1290
1291 void cec_pin_changed(struct cec_adapter *adap, bool value)
1292 {
1293 struct cec_pin *pin = adap->pin;
1294
1295 cec_pin_update(pin, value, false);
1296 if (!value && (adap->is_configuring || adap->is_configured ||
1297 adap->monitor_all_cnt))
1298 atomic_set(&pin->work_irq_change, CEC_PIN_IRQ_DISABLE);
1299 }
1300 EXPORT_SYMBOL_GPL(cec_pin_changed);
1301
1302 static const struct cec_adap_ops cec_pin_adap_ops = {
1303 .adap_enable = cec_pin_adap_enable,
1304 .adap_monitor_all_enable = cec_pin_adap_monitor_all_enable,
1305 .adap_log_addr = cec_pin_adap_log_addr,
1306 .adap_transmit = cec_pin_adap_transmit,
1307 .adap_status = cec_pin_adap_status,
1308 .adap_free = cec_pin_adap_free,
1309 #ifdef CONFIG_CEC_PIN_ERROR_INJ
1310 .error_inj_parse_line = cec_pin_error_inj_parse_line,
1311 .error_inj_show = cec_pin_error_inj_show,
1312 #endif
1313 .received = cec_pin_received,
1314 };
1315
1316 struct cec_adapter *cec_pin_allocate_adapter(const struct cec_pin_ops *pin_ops,
1317 void *priv, const char *name, u32 caps)
1318 {
1319 struct cec_adapter *adap;
1320 struct cec_pin *pin = kzalloc(sizeof(*pin), GFP_KERNEL);
1321
1322 if (pin == NULL)
1323 return ERR_PTR(-ENOMEM);
1324 pin->ops = pin_ops;
1325 hrtimer_init(&pin->timer, CLOCK_MONOTONIC, HRTIMER_MODE_REL);
1326 pin->timer.function = cec_pin_timer;
1327 init_waitqueue_head(&pin->kthread_waitq);
1328 pin->tx_custom_low_usecs = CEC_TIM_CUSTOM_DEFAULT;
1329 pin->tx_custom_high_usecs = CEC_TIM_CUSTOM_DEFAULT;
1330
1331 adap = cec_allocate_adapter(&cec_pin_adap_ops, priv, name,
1332 caps | CEC_CAP_MONITOR_ALL | CEC_CAP_MONITOR_PIN,
1333 CEC_MAX_LOG_ADDRS);
1334
1335 if (IS_ERR(adap)) {
1336 kfree(pin);
1337 return adap;
1338 }
1339
1340 adap->pin = pin;
1341 pin->adap = adap;
1342 cec_pin_update(pin, cec_pin_high(pin), true);
1343 return adap;
1344 }
1345 EXPORT_SYMBOL_GPL(cec_pin_allocate_adapter);
Linux with added FPC-III support