xref: /openbmc/linux/drivers/counter/rz-mtu3-cnt.c (revision 9470114d)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * Renesas RZ/G2L MTU3a Counter driver
4  *
5  * Copyright (C) 2022 Renesas Electronics Corporation
6  */
7 
8 #include <linux/clk.h>
9 #include <linux/counter.h>
10 #include <linux/mfd/rz-mtu3.h>
11 #include <linux/module.h>
12 #include <linux/platform_device.h>
13 #include <linux/pm_runtime.h>
14 #include <linux/types.h>
15 
16 /*
17  * Register descriptions
18  *   TSR: Timer Status Register
19  *   TMDR1: Timer Mode Register 1
20  *   TMDR3: Timer Mode Register 3
21  *   TIOR: Timer I/O Control Register
22  *   TCR: Timer Control Register
23  *   TCNT: Timer Counter
24  *   TGRA: Timer general register A
25  *   TCNTLW: Timer Longword Counter
26  *   TGRALW: Timer longword general register A
27  */
28 
29 #define RZ_MTU3_TSR_TCFD	BIT(7) /* Count Direction Flag */
30 
31 #define RZ_MTU3_TMDR1_PH_CNT_MODE_1	(4) /* Phase counting mode 1 */
32 #define RZ_MTU3_TMDR1_PH_CNT_MODE_2	(5) /* Phase counting mode 2 */
33 #define RZ_MTU3_TMDR1_PH_CNT_MODE_3	(6) /* Phase counting mode 3 */
34 #define RZ_MTU3_TMDR1_PH_CNT_MODE_4	(7) /* Phase counting mode 4 */
35 #define RZ_MTU3_TMDR1_PH_CNT_MODE_5	(9) /* Phase counting mode 5 */
36 #define RZ_MTU3_TMDR1_PH_CNT_MODE_MASK	(0xf)
37 
38 /*
39  * LWA: MTU1/MTU2 Combination Longword Access Control
40  * 0: 16-bit, 1: 32-bit
41  */
42 #define RZ_MTU3_TMDR3_LWA	(0)
43 
44 /*
45  * PHCKSEL: External Input Phase Clock Select
46  * 0: MTCLKA and MTCLKB, 1: MTCLKC and MTCLKD
47  */
48 #define RZ_MTU3_TMDR3_PHCKSEL	(1)
49 
50 #define RZ_MTU3_16_BIT_MTU1_CH	(0)
51 #define RZ_MTU3_16_BIT_MTU2_CH	(1)
52 #define RZ_MTU3_32_BIT_CH	(2)
53 
54 #define RZ_MTU3_TIOR_NO_OUTPUT	(0) /* Output prohibited */
55 #define RZ_MTU3_TIOR_IC_BOTH	(10) /* Input capture at both edges */
56 
57 #define SIGNAL_A_ID	(0)
58 #define SIGNAL_B_ID	(1)
59 #define SIGNAL_C_ID	(2)
60 #define SIGNAL_D_ID	(3)
61 
62 #define RZ_MTU3_MAX_HW_CNTR_CHANNELS	(2)
63 #define RZ_MTU3_MAX_LOGICAL_CNTR_CHANNELS	(3)
64 
65 /**
66  * struct rz_mtu3_cnt - MTU3 counter private data
67  *
68  * @clk: MTU3 module clock
69  * @lock: Lock to prevent concurrent access for ceiling and count
70  * @ch: HW channels for the counters
71  * @count_is_enabled: Enabled state of Counter value channel
72  * @mtu_16bit_max: Cache for 16-bit counters
73  * @mtu_32bit_max: Cache for 32-bit counters
74  */
75 struct rz_mtu3_cnt {
76 	struct clk *clk;
77 	struct mutex lock;
78 	struct rz_mtu3_channel *ch;
79 	bool count_is_enabled[RZ_MTU3_MAX_LOGICAL_CNTR_CHANNELS];
80 	union {
81 		u16 mtu_16bit_max[RZ_MTU3_MAX_HW_CNTR_CHANNELS];
82 		u32 mtu_32bit_max;
83 	};
84 };
85 
86 static const enum counter_function rz_mtu3_count_functions[] = {
87 	COUNTER_FUNCTION_QUADRATURE_X4,
88 	COUNTER_FUNCTION_PULSE_DIRECTION,
89 	COUNTER_FUNCTION_QUADRATURE_X2_B,
90 };
91 
92 static inline size_t rz_mtu3_get_hw_ch(const size_t id)
93 {
94 	return (id == RZ_MTU3_32_BIT_CH) ? 0 : id;
95 }
96 
97 static inline struct rz_mtu3_channel *rz_mtu3_get_ch(struct counter_device *counter, int id)
98 {
99 	struct rz_mtu3_cnt *const priv = counter_priv(counter);
100 	const size_t ch_id = rz_mtu3_get_hw_ch(id);
101 
102 	return &priv->ch[ch_id];
103 }
104 
105 static bool rz_mtu3_is_counter_invalid(struct counter_device *counter, int id)
106 {
107 	struct rz_mtu3_cnt *const priv = counter_priv(counter);
108 	unsigned long tmdr;
109 
110 	pm_runtime_get_sync(priv->ch->dev);
111 	tmdr = rz_mtu3_shared_reg_read(priv->ch, RZ_MTU3_TMDR3);
112 	pm_runtime_put(priv->ch->dev);
113 
114 	if (id == RZ_MTU3_32_BIT_CH && test_bit(RZ_MTU3_TMDR3_LWA, &tmdr))
115 		return false;
116 
117 	if (id != RZ_MTU3_32_BIT_CH && !test_bit(RZ_MTU3_TMDR3_LWA, &tmdr))
118 		return false;
119 
120 	return true;
121 }
122 
123 static int rz_mtu3_lock_if_counter_is_valid(struct counter_device *counter,
124 					    struct rz_mtu3_channel *const ch,
125 					    struct rz_mtu3_cnt *const priv,
126 					    int id)
127 {
128 	mutex_lock(&priv->lock);
129 
130 	if (ch->is_busy && !priv->count_is_enabled[id]) {
131 		mutex_unlock(&priv->lock);
132 		return -EINVAL;
133 	}
134 
135 	if (rz_mtu3_is_counter_invalid(counter, id)) {
136 		mutex_unlock(&priv->lock);
137 		return -EBUSY;
138 	}
139 
140 	return 0;
141 }
142 
143 static int rz_mtu3_lock_if_count_is_enabled(struct rz_mtu3_channel *const ch,
144 					    struct rz_mtu3_cnt *const priv,
145 					    int id)
146 {
147 	mutex_lock(&priv->lock);
148 
149 	if (ch->is_busy && !priv->count_is_enabled[id]) {
150 		mutex_unlock(&priv->lock);
151 		return -EINVAL;
152 	}
153 
154 	return 0;
155 }
156 
157 static int rz_mtu3_count_read(struct counter_device *counter,
158 			      struct counter_count *count, u64 *val)
159 {
160 	struct rz_mtu3_channel *const ch = rz_mtu3_get_ch(counter, count->id);
161 	struct rz_mtu3_cnt *const priv = counter_priv(counter);
162 	int ret;
163 
164 	ret = rz_mtu3_lock_if_counter_is_valid(counter, ch, priv, count->id);
165 	if (ret)
166 		return ret;
167 
168 	pm_runtime_get_sync(ch->dev);
169 	if (count->id == RZ_MTU3_32_BIT_CH)
170 		*val = rz_mtu3_32bit_ch_read(ch, RZ_MTU3_TCNTLW);
171 	else
172 		*val = rz_mtu3_16bit_ch_read(ch, RZ_MTU3_TCNT);
173 	pm_runtime_put(ch->dev);
174 	mutex_unlock(&priv->lock);
175 
176 	return 0;
177 }
178 
179 static int rz_mtu3_count_write(struct counter_device *counter,
180 			       struct counter_count *count, const u64 val)
181 {
182 	struct rz_mtu3_channel *const ch = rz_mtu3_get_ch(counter, count->id);
183 	struct rz_mtu3_cnt *const priv = counter_priv(counter);
184 	int ret;
185 
186 	ret = rz_mtu3_lock_if_counter_is_valid(counter, ch, priv, count->id);
187 	if (ret)
188 		return ret;
189 
190 	pm_runtime_get_sync(ch->dev);
191 	if (count->id == RZ_MTU3_32_BIT_CH)
192 		rz_mtu3_32bit_ch_write(ch, RZ_MTU3_TCNTLW, val);
193 	else
194 		rz_mtu3_16bit_ch_write(ch, RZ_MTU3_TCNT, val);
195 	pm_runtime_put(ch->dev);
196 	mutex_unlock(&priv->lock);
197 
198 	return 0;
199 }
200 
201 static int rz_mtu3_count_function_read_helper(struct rz_mtu3_channel *const ch,
202 					      struct rz_mtu3_cnt *const priv,
203 					      enum counter_function *function)
204 {
205 	u8 timer_mode;
206 
207 	pm_runtime_get_sync(ch->dev);
208 	timer_mode = rz_mtu3_8bit_ch_read(ch, RZ_MTU3_TMDR1);
209 	pm_runtime_put(ch->dev);
210 
211 	switch (timer_mode & RZ_MTU3_TMDR1_PH_CNT_MODE_MASK) {
212 	case RZ_MTU3_TMDR1_PH_CNT_MODE_1:
213 		*function = COUNTER_FUNCTION_QUADRATURE_X4;
214 		return 0;
215 	case RZ_MTU3_TMDR1_PH_CNT_MODE_2:
216 		*function = COUNTER_FUNCTION_PULSE_DIRECTION;
217 		return 0;
218 	case RZ_MTU3_TMDR1_PH_CNT_MODE_4:
219 		*function = COUNTER_FUNCTION_QUADRATURE_X2_B;
220 		return 0;
221 	default:
222 		/*
223 		 * TODO:
224 		 *  - need to add RZ_MTU3_TMDR1_PH_CNT_MODE_3
225 		 *  - need to add RZ_MTU3_TMDR1_PH_CNT_MODE_5
226 		 */
227 		return -EINVAL;
228 	}
229 }
230 
231 static int rz_mtu3_count_function_read(struct counter_device *counter,
232 				       struct counter_count *count,
233 				       enum counter_function *function)
234 {
235 	struct rz_mtu3_channel *const ch = rz_mtu3_get_ch(counter, count->id);
236 	struct rz_mtu3_cnt *const priv = counter_priv(counter);
237 	int ret;
238 
239 	ret = rz_mtu3_lock_if_count_is_enabled(ch, priv, count->id);
240 	if (ret)
241 		return ret;
242 
243 	ret = rz_mtu3_count_function_read_helper(ch, priv, function);
244 	mutex_unlock(&priv->lock);
245 
246 	return ret;
247 }
248 
249 static int rz_mtu3_count_function_write(struct counter_device *counter,
250 					struct counter_count *count,
251 					enum counter_function function)
252 {
253 	struct rz_mtu3_channel *const ch = rz_mtu3_get_ch(counter, count->id);
254 	struct rz_mtu3_cnt *const priv = counter_priv(counter);
255 	u8 timer_mode;
256 	int ret;
257 
258 	ret = rz_mtu3_lock_if_count_is_enabled(ch, priv, count->id);
259 	if (ret)
260 		return ret;
261 
262 	switch (function) {
263 	case COUNTER_FUNCTION_QUADRATURE_X4:
264 		timer_mode = RZ_MTU3_TMDR1_PH_CNT_MODE_1;
265 		break;
266 	case COUNTER_FUNCTION_PULSE_DIRECTION:
267 		timer_mode = RZ_MTU3_TMDR1_PH_CNT_MODE_2;
268 		break;
269 	case COUNTER_FUNCTION_QUADRATURE_X2_B:
270 		timer_mode = RZ_MTU3_TMDR1_PH_CNT_MODE_4;
271 		break;
272 	default:
273 		/*
274 		 * TODO:
275 		 *  - need to add RZ_MTU3_TMDR1_PH_CNT_MODE_3
276 		 *  - need to add RZ_MTU3_TMDR1_PH_CNT_MODE_5
277 		 */
278 		mutex_unlock(&priv->lock);
279 		return -EINVAL;
280 	}
281 
282 	pm_runtime_get_sync(ch->dev);
283 	rz_mtu3_8bit_ch_write(ch, RZ_MTU3_TMDR1, timer_mode);
284 	pm_runtime_put(ch->dev);
285 	mutex_unlock(&priv->lock);
286 
287 	return 0;
288 }
289 
290 static int rz_mtu3_count_direction_read(struct counter_device *counter,
291 					struct counter_count *count,
292 					enum counter_count_direction *direction)
293 {
294 	struct rz_mtu3_channel *const ch = rz_mtu3_get_ch(counter, count->id);
295 	struct rz_mtu3_cnt *const priv = counter_priv(counter);
296 	int ret;
297 	u8 tsr;
298 
299 	ret = rz_mtu3_lock_if_count_is_enabled(ch, priv, count->id);
300 	if (ret)
301 		return ret;
302 
303 	pm_runtime_get_sync(ch->dev);
304 	tsr = rz_mtu3_8bit_ch_read(ch, RZ_MTU3_TSR);
305 	pm_runtime_put(ch->dev);
306 
307 	*direction = (tsr & RZ_MTU3_TSR_TCFD) ?
308 		COUNTER_COUNT_DIRECTION_FORWARD : COUNTER_COUNT_DIRECTION_BACKWARD;
309 	mutex_unlock(&priv->lock);
310 
311 	return 0;
312 }
313 
314 static int rz_mtu3_count_ceiling_read(struct counter_device *counter,
315 				      struct counter_count *count,
316 				      u64 *ceiling)
317 {
318 	struct rz_mtu3_channel *const ch = rz_mtu3_get_ch(counter, count->id);
319 	struct rz_mtu3_cnt *const priv = counter_priv(counter);
320 	const size_t ch_id = rz_mtu3_get_hw_ch(count->id);
321 	int ret;
322 
323 	ret = rz_mtu3_lock_if_counter_is_valid(counter, ch, priv, count->id);
324 	if (ret)
325 		return ret;
326 
327 	switch (count->id) {
328 	case RZ_MTU3_16_BIT_MTU1_CH:
329 	case RZ_MTU3_16_BIT_MTU2_CH:
330 		*ceiling = priv->mtu_16bit_max[ch_id];
331 		break;
332 	case RZ_MTU3_32_BIT_CH:
333 		*ceiling = priv->mtu_32bit_max;
334 		break;
335 	default:
336 		/* should never reach this path */
337 		mutex_unlock(&priv->lock);
338 		return -EINVAL;
339 	}
340 
341 	mutex_unlock(&priv->lock);
342 	return 0;
343 }
344 
345 static int rz_mtu3_count_ceiling_write(struct counter_device *counter,
346 				       struct counter_count *count,
347 				       u64 ceiling)
348 {
349 	struct rz_mtu3_channel *const ch = rz_mtu3_get_ch(counter, count->id);
350 	struct rz_mtu3_cnt *const priv = counter_priv(counter);
351 	const size_t ch_id = rz_mtu3_get_hw_ch(count->id);
352 	int ret;
353 
354 	ret = rz_mtu3_lock_if_counter_is_valid(counter, ch, priv, count->id);
355 	if (ret)
356 		return ret;
357 
358 	switch (count->id) {
359 	case RZ_MTU3_16_BIT_MTU1_CH:
360 	case RZ_MTU3_16_BIT_MTU2_CH:
361 		if (ceiling > U16_MAX) {
362 			mutex_unlock(&priv->lock);
363 			return -ERANGE;
364 		}
365 		priv->mtu_16bit_max[ch_id] = ceiling;
366 		break;
367 	case RZ_MTU3_32_BIT_CH:
368 		if (ceiling > U32_MAX) {
369 			mutex_unlock(&priv->lock);
370 			return -ERANGE;
371 		}
372 		priv->mtu_32bit_max = ceiling;
373 		break;
374 	default:
375 		/* should never reach this path */
376 		mutex_unlock(&priv->lock);
377 		return -EINVAL;
378 	}
379 
380 	pm_runtime_get_sync(ch->dev);
381 	if (count->id == RZ_MTU3_32_BIT_CH)
382 		rz_mtu3_32bit_ch_write(ch, RZ_MTU3_TGRALW, ceiling);
383 	else
384 		rz_mtu3_16bit_ch_write(ch, RZ_MTU3_TGRA, ceiling);
385 
386 	rz_mtu3_8bit_ch_write(ch, RZ_MTU3_TCR, RZ_MTU3_TCR_CCLR_TGRA);
387 	pm_runtime_put(ch->dev);
388 	mutex_unlock(&priv->lock);
389 
390 	return 0;
391 }
392 
393 static void rz_mtu3_32bit_cnt_setting(struct counter_device *counter)
394 {
395 	struct rz_mtu3_channel *const ch1 = rz_mtu3_get_ch(counter, 0);
396 	struct rz_mtu3_channel *const ch2 = rz_mtu3_get_ch(counter, 1);
397 
398 	/* Phase counting mode 1 is used as default in initialization. */
399 	rz_mtu3_8bit_ch_write(ch1, RZ_MTU3_TMDR1, RZ_MTU3_TMDR1_PH_CNT_MODE_1);
400 
401 	rz_mtu3_8bit_ch_write(ch1, RZ_MTU3_TCR, RZ_MTU3_TCR_CCLR_TGRA);
402 	rz_mtu3_8bit_ch_write(ch1, RZ_MTU3_TIOR, RZ_MTU3_TIOR_IC_BOTH);
403 
404 	rz_mtu3_enable(ch1);
405 	rz_mtu3_enable(ch2);
406 }
407 
408 static void rz_mtu3_16bit_cnt_setting(struct counter_device *counter, int id)
409 {
410 	struct rz_mtu3_channel *const ch = rz_mtu3_get_ch(counter, id);
411 
412 	/* Phase counting mode 1 is used as default in initialization. */
413 	rz_mtu3_8bit_ch_write(ch, RZ_MTU3_TMDR1, RZ_MTU3_TMDR1_PH_CNT_MODE_1);
414 
415 	rz_mtu3_8bit_ch_write(ch, RZ_MTU3_TCR, RZ_MTU3_TCR_CCLR_TGRA);
416 	rz_mtu3_8bit_ch_write(ch, RZ_MTU3_TIOR, RZ_MTU3_TIOR_NO_OUTPUT);
417 	rz_mtu3_enable(ch);
418 }
419 
420 static int rz_mtu3_initialize_counter(struct counter_device *counter, int id)
421 {
422 	struct rz_mtu3_channel *const ch = rz_mtu3_get_ch(counter, id);
423 	struct rz_mtu3_channel *const ch1 = rz_mtu3_get_ch(counter, 0);
424 	struct rz_mtu3_channel *const ch2 = rz_mtu3_get_ch(counter, 1);
425 
426 	switch (id) {
427 	case RZ_MTU3_16_BIT_MTU1_CH:
428 	case RZ_MTU3_16_BIT_MTU2_CH:
429 		if (!rz_mtu3_request_channel(ch))
430 			return -EBUSY;
431 
432 		rz_mtu3_16bit_cnt_setting(counter, id);
433 		return 0;
434 	case RZ_MTU3_32_BIT_CH:
435 		/*
436 		 * 32-bit phase counting need MTU1 and MTU2 to create 32-bit
437 		 * cascade counter.
438 		 */
439 		if (!rz_mtu3_request_channel(ch1))
440 			return -EBUSY;
441 
442 		if (!rz_mtu3_request_channel(ch2)) {
443 			rz_mtu3_release_channel(ch1);
444 			return -EBUSY;
445 		}
446 
447 		rz_mtu3_32bit_cnt_setting(counter);
448 		return 0;
449 	default:
450 		/* should never reach this path */
451 		return -EINVAL;
452 	}
453 }
454 
455 static void rz_mtu3_terminate_counter(struct counter_device *counter, int id)
456 {
457 	struct rz_mtu3_channel *const ch = rz_mtu3_get_ch(counter, id);
458 	struct rz_mtu3_channel *const ch1 = rz_mtu3_get_ch(counter, 0);
459 	struct rz_mtu3_channel *const ch2 = rz_mtu3_get_ch(counter, 1);
460 
461 	if (id == RZ_MTU3_32_BIT_CH) {
462 		rz_mtu3_release_channel(ch2);
463 		rz_mtu3_release_channel(ch1);
464 		rz_mtu3_disable(ch2);
465 		rz_mtu3_disable(ch1);
466 	} else {
467 		rz_mtu3_release_channel(ch);
468 		rz_mtu3_disable(ch);
469 	}
470 }
471 
472 static int rz_mtu3_count_enable_read(struct counter_device *counter,
473 				     struct counter_count *count, u8 *enable)
474 {
475 	struct rz_mtu3_channel *const ch = rz_mtu3_get_ch(counter, count->id);
476 	struct rz_mtu3_channel *const ch1 = rz_mtu3_get_ch(counter, 0);
477 	struct rz_mtu3_channel *const ch2 = rz_mtu3_get_ch(counter, 1);
478 	struct rz_mtu3_cnt *const priv = counter_priv(counter);
479 	int ret;
480 
481 	ret = rz_mtu3_lock_if_count_is_enabled(ch, priv, count->id);
482 	if (ret)
483 		return ret;
484 
485 	if (count->id == RZ_MTU3_32_BIT_CH)
486 		*enable = rz_mtu3_is_enabled(ch1) && rz_mtu3_is_enabled(ch2);
487 	else
488 		*enable = rz_mtu3_is_enabled(ch);
489 
490 	mutex_unlock(&priv->lock);
491 
492 	return 0;
493 }
494 
495 static int rz_mtu3_count_enable_write(struct counter_device *counter,
496 				      struct counter_count *count, u8 enable)
497 {
498 	struct rz_mtu3_channel *const ch = rz_mtu3_get_ch(counter, count->id);
499 	struct rz_mtu3_cnt *const priv = counter_priv(counter);
500 	int ret = 0;
501 
502 	if (enable) {
503 		mutex_lock(&priv->lock);
504 		pm_runtime_get_sync(ch->dev);
505 		ret = rz_mtu3_initialize_counter(counter, count->id);
506 		if (ret == 0)
507 			priv->count_is_enabled[count->id] = true;
508 		mutex_unlock(&priv->lock);
509 	} else {
510 		mutex_lock(&priv->lock);
511 		rz_mtu3_terminate_counter(counter, count->id);
512 		priv->count_is_enabled[count->id] = false;
513 		pm_runtime_put(ch->dev);
514 		mutex_unlock(&priv->lock);
515 	}
516 
517 	return ret;
518 }
519 
520 static int rz_mtu3_lock_if_ch0_is_enabled(struct rz_mtu3_cnt *const priv)
521 {
522 	mutex_lock(&priv->lock);
523 	if (priv->ch->is_busy && !(priv->count_is_enabled[RZ_MTU3_16_BIT_MTU1_CH] ||
524 				   priv->count_is_enabled[RZ_MTU3_32_BIT_CH])) {
525 		mutex_unlock(&priv->lock);
526 		return -EINVAL;
527 	}
528 
529 	return 0;
530 }
531 
532 static int rz_mtu3_cascade_counts_enable_get(struct counter_device *counter,
533 					     u8 *cascade_enable)
534 {
535 	struct rz_mtu3_cnt *const priv = counter_priv(counter);
536 	unsigned long tmdr;
537 	int ret;
538 
539 	ret = rz_mtu3_lock_if_ch0_is_enabled(priv);
540 	if (ret)
541 		return ret;
542 
543 	pm_runtime_get_sync(priv->ch->dev);
544 	tmdr = rz_mtu3_shared_reg_read(priv->ch, RZ_MTU3_TMDR3);
545 	pm_runtime_put(priv->ch->dev);
546 	*cascade_enable = test_bit(RZ_MTU3_TMDR3_LWA, &tmdr);
547 	mutex_unlock(&priv->lock);
548 
549 	return 0;
550 }
551 
552 static int rz_mtu3_cascade_counts_enable_set(struct counter_device *counter,
553 					     u8 cascade_enable)
554 {
555 	struct rz_mtu3_cnt *const priv = counter_priv(counter);
556 	int ret;
557 
558 	ret = rz_mtu3_lock_if_ch0_is_enabled(priv);
559 	if (ret)
560 		return ret;
561 
562 	pm_runtime_get_sync(priv->ch->dev);
563 	rz_mtu3_shared_reg_update_bit(priv->ch, RZ_MTU3_TMDR3,
564 				      RZ_MTU3_TMDR3_LWA, cascade_enable);
565 	pm_runtime_put(priv->ch->dev);
566 	mutex_unlock(&priv->lock);
567 
568 	return 0;
569 }
570 
571 static int rz_mtu3_ext_input_phase_clock_select_get(struct counter_device *counter,
572 						    u32 *ext_input_phase_clock_select)
573 {
574 	struct rz_mtu3_cnt *const priv = counter_priv(counter);
575 	unsigned long tmdr;
576 	int ret;
577 
578 	ret = rz_mtu3_lock_if_ch0_is_enabled(priv);
579 	if (ret)
580 		return ret;
581 
582 	pm_runtime_get_sync(priv->ch->dev);
583 	tmdr = rz_mtu3_shared_reg_read(priv->ch, RZ_MTU3_TMDR3);
584 	pm_runtime_put(priv->ch->dev);
585 	*ext_input_phase_clock_select = test_bit(RZ_MTU3_TMDR3_PHCKSEL, &tmdr);
586 	mutex_unlock(&priv->lock);
587 
588 	return 0;
589 }
590 
591 static int rz_mtu3_ext_input_phase_clock_select_set(struct counter_device *counter,
592 						    u32 ext_input_phase_clock_select)
593 {
594 	struct rz_mtu3_cnt *const priv = counter_priv(counter);
595 	int ret;
596 
597 	ret = rz_mtu3_lock_if_ch0_is_enabled(priv);
598 	if (ret)
599 		return ret;
600 
601 	pm_runtime_get_sync(priv->ch->dev);
602 	rz_mtu3_shared_reg_update_bit(priv->ch, RZ_MTU3_TMDR3,
603 				      RZ_MTU3_TMDR3_PHCKSEL,
604 				      ext_input_phase_clock_select);
605 	pm_runtime_put(priv->ch->dev);
606 	mutex_unlock(&priv->lock);
607 
608 	return 0;
609 }
610 
611 static struct counter_comp rz_mtu3_count_ext[] = {
612 	COUNTER_COMP_DIRECTION(rz_mtu3_count_direction_read),
613 	COUNTER_COMP_ENABLE(rz_mtu3_count_enable_read,
614 			    rz_mtu3_count_enable_write),
615 	COUNTER_COMP_CEILING(rz_mtu3_count_ceiling_read,
616 			     rz_mtu3_count_ceiling_write),
617 };
618 
619 static const enum counter_synapse_action rz_mtu3_synapse_actions[] = {
620 	COUNTER_SYNAPSE_ACTION_BOTH_EDGES,
621 	COUNTER_SYNAPSE_ACTION_RISING_EDGE,
622 	COUNTER_SYNAPSE_ACTION_NONE,
623 };
624 
625 static int rz_mtu3_action_read(struct counter_device *counter,
626 			       struct counter_count *count,
627 			       struct counter_synapse *synapse,
628 			       enum counter_synapse_action *action)
629 {
630 	const bool is_signal_ab = (synapse->signal->id == SIGNAL_A_ID) ||
631 				  (synapse->signal->id == SIGNAL_B_ID);
632 	struct rz_mtu3_channel *const ch = rz_mtu3_get_ch(counter, count->id);
633 	struct rz_mtu3_cnt *const priv = counter_priv(counter);
634 	enum counter_function function;
635 	bool mtclkc_mtclkd;
636 	unsigned long tmdr;
637 	int ret;
638 
639 	ret = rz_mtu3_lock_if_count_is_enabled(ch, priv, count->id);
640 	if (ret)
641 		return ret;
642 
643 	ret = rz_mtu3_count_function_read_helper(ch, priv, &function);
644 	if (ret) {
645 		mutex_unlock(&priv->lock);
646 		return ret;
647 	}
648 
649 	/* Default action mode */
650 	*action = COUNTER_SYNAPSE_ACTION_NONE;
651 
652 	if (count->id != RZ_MTU3_16_BIT_MTU1_CH) {
653 		tmdr = rz_mtu3_shared_reg_read(priv->ch, RZ_MTU3_TMDR3);
654 		mtclkc_mtclkd = test_bit(RZ_MTU3_TMDR3_PHCKSEL, &tmdr);
655 		if ((mtclkc_mtclkd && is_signal_ab) ||
656 		    (!mtclkc_mtclkd && !is_signal_ab)) {
657 			mutex_unlock(&priv->lock);
658 			return 0;
659 		}
660 	}
661 
662 	switch (function) {
663 	case COUNTER_FUNCTION_PULSE_DIRECTION:
664 		/*
665 		 * Rising edges on signal A (signal C) updates the respective
666 		 * count. The input level of signal B (signal D) determines
667 		 * direction.
668 		 */
669 		if (synapse->signal->id == SIGNAL_A_ID ||
670 		    synapse->signal->id == SIGNAL_C_ID)
671 			*action = COUNTER_SYNAPSE_ACTION_RISING_EDGE;
672 		break;
673 	case COUNTER_FUNCTION_QUADRATURE_X2_B:
674 		/*
675 		 * Any state transition on quadrature pair signal B (signal D)
676 		 * updates the respective count.
677 		 */
678 		if (synapse->signal->id == SIGNAL_B_ID ||
679 		    synapse->signal->id == SIGNAL_D_ID)
680 			*action = COUNTER_SYNAPSE_ACTION_BOTH_EDGES;
681 		break;
682 	case COUNTER_FUNCTION_QUADRATURE_X4:
683 		/* counts up/down on both edges of A (C)  and B (D) signal */
684 		*action = COUNTER_SYNAPSE_ACTION_BOTH_EDGES;
685 		break;
686 	default:
687 		/* should never reach this path */
688 		mutex_unlock(&priv->lock);
689 		return -EINVAL;
690 	}
691 
692 	mutex_unlock(&priv->lock);
693 
694 	return 0;
695 }
696 
697 static const struct counter_ops rz_mtu3_cnt_ops = {
698 	.count_read = rz_mtu3_count_read,
699 	.count_write = rz_mtu3_count_write,
700 	.function_read = rz_mtu3_count_function_read,
701 	.function_write = rz_mtu3_count_function_write,
702 	.action_read = rz_mtu3_action_read,
703 };
704 
705 #define RZ_MTU3_PHASE_SIGNAL(_id, _name) {		\
706 	.id = (_id),				\
707 	.name = (_name),			\
708 }
709 
710 static struct counter_signal rz_mtu3_signals[] = {
711 	RZ_MTU3_PHASE_SIGNAL(SIGNAL_A_ID, "MTU1 MTCLKA"),
712 	RZ_MTU3_PHASE_SIGNAL(SIGNAL_B_ID, "MTU1 MTCLKB"),
713 	RZ_MTU3_PHASE_SIGNAL(SIGNAL_C_ID, "MTU2 MTCLKC"),
714 	RZ_MTU3_PHASE_SIGNAL(SIGNAL_D_ID, "MTU2 MTCLKD"),
715 };
716 
717 static struct counter_synapse rz_mtu3_mtu1_count_synapses[] = {
718 	{
719 		.actions_list = rz_mtu3_synapse_actions,
720 		.num_actions = ARRAY_SIZE(rz_mtu3_synapse_actions),
721 		.signal = rz_mtu3_signals,
722 	},
723 	{
724 		.actions_list = rz_mtu3_synapse_actions,
725 		.num_actions = ARRAY_SIZE(rz_mtu3_synapse_actions),
726 		.signal = rz_mtu3_signals + 1,
727 	}
728 };
729 
730 static struct counter_synapse rz_mtu3_mtu2_count_synapses[] = {
731 	{
732 		.actions_list = rz_mtu3_synapse_actions,
733 		.num_actions = ARRAY_SIZE(rz_mtu3_synapse_actions),
734 		.signal = rz_mtu3_signals,
735 	},
736 	{
737 		.actions_list = rz_mtu3_synapse_actions,
738 		.num_actions = ARRAY_SIZE(rz_mtu3_synapse_actions),
739 		.signal = rz_mtu3_signals + 1,
740 	},
741 	{
742 		.actions_list = rz_mtu3_synapse_actions,
743 		.num_actions = ARRAY_SIZE(rz_mtu3_synapse_actions),
744 		.signal = rz_mtu3_signals + 2,
745 	},
746 	{
747 		.actions_list = rz_mtu3_synapse_actions,
748 		.num_actions = ARRAY_SIZE(rz_mtu3_synapse_actions),
749 		.signal = rz_mtu3_signals + 3,
750 	}
751 };
752 
753 static struct counter_count rz_mtu3_counts[] = {
754 	{
755 		.id = RZ_MTU3_16_BIT_MTU1_CH,
756 		.name = "Channel 1 Count",
757 		.functions_list = rz_mtu3_count_functions,
758 		.num_functions = ARRAY_SIZE(rz_mtu3_count_functions),
759 		.synapses = rz_mtu3_mtu1_count_synapses,
760 		.num_synapses = ARRAY_SIZE(rz_mtu3_mtu1_count_synapses),
761 		.ext = rz_mtu3_count_ext,
762 		.num_ext = ARRAY_SIZE(rz_mtu3_count_ext),
763 	},
764 	{
765 		.id = RZ_MTU3_16_BIT_MTU2_CH,
766 		.name = "Channel 2 Count",
767 		.functions_list = rz_mtu3_count_functions,
768 		.num_functions = ARRAY_SIZE(rz_mtu3_count_functions),
769 		.synapses = rz_mtu3_mtu2_count_synapses,
770 		.num_synapses = ARRAY_SIZE(rz_mtu3_mtu2_count_synapses),
771 		.ext = rz_mtu3_count_ext,
772 		.num_ext = ARRAY_SIZE(rz_mtu3_count_ext),
773 	},
774 	{
775 		.id = RZ_MTU3_32_BIT_CH,
776 		.name = "Channel 1 and 2 (cascaded) Count",
777 		.functions_list = rz_mtu3_count_functions,
778 		.num_functions = ARRAY_SIZE(rz_mtu3_count_functions),
779 		.synapses = rz_mtu3_mtu2_count_synapses,
780 		.num_synapses = ARRAY_SIZE(rz_mtu3_mtu2_count_synapses),
781 		.ext = rz_mtu3_count_ext,
782 		.num_ext = ARRAY_SIZE(rz_mtu3_count_ext),
783 	}
784 };
785 
786 static const char *const rz_mtu3_ext_input_phase_clock_select[] = {
787 	"MTCLKA-MTCLKB",
788 	"MTCLKC-MTCLKD",
789 };
790 
791 static DEFINE_COUNTER_ENUM(rz_mtu3_ext_input_phase_clock_select_enum,
792 			   rz_mtu3_ext_input_phase_clock_select);
793 
794 static struct counter_comp rz_mtu3_device_ext[] = {
795 	COUNTER_COMP_DEVICE_BOOL("cascade_counts_enable",
796 				 rz_mtu3_cascade_counts_enable_get,
797 				 rz_mtu3_cascade_counts_enable_set),
798 	COUNTER_COMP_DEVICE_ENUM("external_input_phase_clock_select",
799 				 rz_mtu3_ext_input_phase_clock_select_get,
800 				 rz_mtu3_ext_input_phase_clock_select_set,
801 				 rz_mtu3_ext_input_phase_clock_select_enum),
802 };
803 
804 static int rz_mtu3_cnt_pm_runtime_suspend(struct device *dev)
805 {
806 	struct clk *const clk = dev_get_drvdata(dev);
807 
808 	clk_disable_unprepare(clk);
809 
810 	return 0;
811 }
812 
813 static int rz_mtu3_cnt_pm_runtime_resume(struct device *dev)
814 {
815 	struct clk *const clk = dev_get_drvdata(dev);
816 
817 	clk_prepare_enable(clk);
818 
819 	return 0;
820 }
821 
822 static DEFINE_RUNTIME_DEV_PM_OPS(rz_mtu3_cnt_pm_ops,
823 				 rz_mtu3_cnt_pm_runtime_suspend,
824 				 rz_mtu3_cnt_pm_runtime_resume, NULL);
825 
826 static void rz_mtu3_cnt_pm_disable(void *data)
827 {
828 	struct device *dev = data;
829 
830 	pm_runtime_disable(dev);
831 	pm_runtime_set_suspended(dev);
832 }
833 
834 static int rz_mtu3_cnt_probe(struct platform_device *pdev)
835 {
836 	struct rz_mtu3 *ddata = dev_get_drvdata(pdev->dev.parent);
837 	struct device *dev = &pdev->dev;
838 	struct counter_device *counter;
839 	struct rz_mtu3_channel *ch;
840 	struct rz_mtu3_cnt *priv;
841 	unsigned int i;
842 	int ret;
843 
844 	counter = devm_counter_alloc(dev, sizeof(*priv));
845 	if (!counter)
846 		return -ENOMEM;
847 
848 	priv = counter_priv(counter);
849 	priv->clk = ddata->clk;
850 	priv->mtu_32bit_max = U32_MAX;
851 	priv->ch = &ddata->channels[RZ_MTU3_CHAN_1];
852 	ch = &priv->ch[0];
853 	for (i = 0; i < RZ_MTU3_MAX_HW_CNTR_CHANNELS; i++) {
854 		ch->dev = dev;
855 		priv->mtu_16bit_max[i] = U16_MAX;
856 		ch++;
857 	}
858 
859 	mutex_init(&priv->lock);
860 	platform_set_drvdata(pdev, priv->clk);
861 	clk_prepare_enable(priv->clk);
862 	pm_runtime_set_active(&pdev->dev);
863 	pm_runtime_enable(&pdev->dev);
864 	ret = devm_add_action_or_reset(&pdev->dev, rz_mtu3_cnt_pm_disable, dev);
865 	if (ret < 0)
866 		goto disable_clock;
867 
868 	counter->name = dev_name(dev);
869 	counter->parent = dev;
870 	counter->ops = &rz_mtu3_cnt_ops;
871 	counter->counts = rz_mtu3_counts;
872 	counter->num_counts = ARRAY_SIZE(rz_mtu3_counts);
873 	counter->signals = rz_mtu3_signals;
874 	counter->num_signals = ARRAY_SIZE(rz_mtu3_signals);
875 	counter->ext = rz_mtu3_device_ext;
876 	counter->num_ext = ARRAY_SIZE(rz_mtu3_device_ext);
877 
878 	/* Register Counter device */
879 	ret = devm_counter_add(dev, counter);
880 	if (ret < 0) {
881 		dev_err_probe(dev, ret, "Failed to add counter\n");
882 		goto disable_clock;
883 	}
884 
885 	return 0;
886 
887 disable_clock:
888 	clk_disable_unprepare(priv->clk);
889 
890 	return ret;
891 }
892 
893 static struct platform_driver rz_mtu3_cnt_driver = {
894 	.probe = rz_mtu3_cnt_probe,
895 	.driver = {
896 		.name = "rz-mtu3-counter",
897 		.pm = pm_ptr(&rz_mtu3_cnt_pm_ops),
898 	},
899 };
900 module_platform_driver(rz_mtu3_cnt_driver);
901 
902 MODULE_AUTHOR("Biju Das <biju.das.jz@bp.renesas.com>");
903 MODULE_ALIAS("platform:rz-mtu3-counter");
904 MODULE_DESCRIPTION("Renesas RZ/G2L MTU3a counter driver");
905 MODULE_LICENSE("GPL");
906 MODULE_IMPORT_NS(COUNTER);
907