xref: /linux/drivers/pwm/pwm-rz-mtu3.c (revision 79790b6818e96c58fe2bffee1b418c16e64e7b80)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * Renesas RZ/G2L MTU3a PWM Timer driver
4  *
5  * Copyright (C) 2023 Renesas Electronics Corporation
6  *
7  * Hardware manual for this IP can be found here
8  * https://www.renesas.com/eu/en/document/mah/rzg2l-group-rzg2lc-group-users-manual-hardware-0?language=en
9  *
10  * Limitations:
11  * - When PWM is disabled, the output is driven to Hi-Z.
12  * - While the hardware supports both polarities, the driver (for now)
13  *   only handles normal polarity.
14  * - HW uses one counter and two match components to configure duty_cycle
15  *   and period.
16  * - Multi-Function Timer Pulse Unit (a.k.a MTU) has 7 HW channels for PWM
17  *   operations. (The channels are MTU{0..4, 6, 7}.)
18  * - MTU{1, 2} channels have a single IO, whereas all other HW channels have
19  *   2 IOs.
20  * - Each IO is modelled as an independent PWM channel.
21  * - rz_mtu3_channel_io_map table is used to map the PWM channel to the
22  *   corresponding HW channel as there are difference in number of IOs
23  *   between HW channels.
24  */
25 
26 #include <linux/bitfield.h>
27 #include <linux/clk.h>
28 #include <linux/limits.h>
29 #include <linux/mfd/rz-mtu3.h>
30 #include <linux/module.h>
31 #include <linux/platform_device.h>
32 #include <linux/pm_runtime.h>
33 #include <linux/pwm.h>
34 #include <linux/time.h>
35 
36 #define RZ_MTU3_MAX_PWM_CHANNELS	12
37 #define RZ_MTU3_MAX_HW_CHANNELS		7
38 
39 /**
40  * struct rz_mtu3_channel_io_map - MTU3 pwm channel map
41  *
42  * @base_pwm_number: First PWM of a channel
43  * @num_channel_ios: number of IOs on the HW channel.
44  */
45 struct rz_mtu3_channel_io_map {
46 	u8 base_pwm_number;
47 	u8 num_channel_ios;
48 };
49 
50 /**
51  * struct rz_mtu3_pwm_channel - MTU3 pwm channel data
52  *
53  * @mtu: MTU3 channel data
54  * @map: MTU3 pwm channel map
55  */
56 struct rz_mtu3_pwm_channel {
57 	struct rz_mtu3_channel *mtu;
58 	const struct rz_mtu3_channel_io_map *map;
59 };
60 
61 /**
62  * struct rz_mtu3_pwm_chip - MTU3 pwm private data
63  *
64  * @clk: MTU3 module clock
65  * @lock: Lock to prevent concurrent access for usage count
66  * @rate: MTU3 clock rate
67  * @user_count: MTU3 usage count
68  * @enable_count: MTU3 enable count
69  * @prescale: MTU3 prescale
70  * @channel_data: MTU3 pwm channel data
71  */
72 
73 struct rz_mtu3_pwm_chip {
74 	struct clk *clk;
75 	struct mutex lock;
76 	unsigned long rate;
77 	u32 user_count[RZ_MTU3_MAX_HW_CHANNELS];
78 	u32 enable_count[RZ_MTU3_MAX_HW_CHANNELS];
79 	u8 prescale[RZ_MTU3_MAX_HW_CHANNELS];
80 	struct rz_mtu3_pwm_channel channel_data[RZ_MTU3_MAX_HW_CHANNELS];
81 };
82 
83 /*
84  * The MTU channels are {0..4, 6, 7} and the number of IO on MTU1
85  * and MTU2 channel is 1 compared to 2 on others.
86  */
87 static const struct rz_mtu3_channel_io_map channel_map[] = {
88 	{ 0, 2 }, { 2, 1 }, { 3, 1 }, { 4, 2 }, { 6, 2 }, { 8, 2 }, { 10, 2 }
89 };
90 
to_rz_mtu3_pwm_chip(struct pwm_chip * chip)91 static inline struct rz_mtu3_pwm_chip *to_rz_mtu3_pwm_chip(struct pwm_chip *chip)
92 {
93 	return pwmchip_get_drvdata(chip);
94 }
95 
rz_mtu3_pwm_read_tgr_registers(struct rz_mtu3_pwm_channel * priv,u16 reg_pv_offset,u16 * pv_val,u16 reg_dc_offset,u16 * dc_val)96 static void rz_mtu3_pwm_read_tgr_registers(struct rz_mtu3_pwm_channel *priv,
97 					   u16 reg_pv_offset, u16 *pv_val,
98 					   u16 reg_dc_offset, u16 *dc_val)
99 {
100 	*pv_val = rz_mtu3_16bit_ch_read(priv->mtu, reg_pv_offset);
101 	*dc_val = rz_mtu3_16bit_ch_read(priv->mtu, reg_dc_offset);
102 }
103 
rz_mtu3_pwm_write_tgr_registers(struct rz_mtu3_pwm_channel * priv,u16 reg_pv_offset,u16 pv_val,u16 reg_dc_offset,u16 dc_val)104 static void rz_mtu3_pwm_write_tgr_registers(struct rz_mtu3_pwm_channel *priv,
105 					    u16 reg_pv_offset, u16 pv_val,
106 					    u16 reg_dc_offset, u16 dc_val)
107 {
108 	rz_mtu3_16bit_ch_write(priv->mtu, reg_pv_offset, pv_val);
109 	rz_mtu3_16bit_ch_write(priv->mtu, reg_dc_offset, dc_val);
110 }
111 
rz_mtu3_pwm_calculate_prescale(struct rz_mtu3_pwm_chip * rz_mtu3,u64 period_cycles)112 static u8 rz_mtu3_pwm_calculate_prescale(struct rz_mtu3_pwm_chip *rz_mtu3,
113 					 u64 period_cycles)
114 {
115 	u32 prescaled_period_cycles;
116 	u8 prescale;
117 
118 	/*
119 	 * Supported prescale values are 1, 4, 16 and 64.
120 	 * TODO: Support prescale values 2, 8, 32, 256 and 1024.
121 	 */
122 	prescaled_period_cycles = period_cycles >> 16;
123 	if (prescaled_period_cycles >= 16)
124 		prescale = 3;
125 	else
126 		prescale = (fls(prescaled_period_cycles) + 1) / 2;
127 
128 	return prescale;
129 }
130 
131 static struct rz_mtu3_pwm_channel *
rz_mtu3_get_channel(struct rz_mtu3_pwm_chip * rz_mtu3_pwm,u32 hwpwm)132 rz_mtu3_get_channel(struct rz_mtu3_pwm_chip *rz_mtu3_pwm, u32 hwpwm)
133 {
134 	struct rz_mtu3_pwm_channel *priv = rz_mtu3_pwm->channel_data;
135 	unsigned int ch;
136 
137 	for (ch = 0; ch < RZ_MTU3_MAX_HW_CHANNELS; ch++, priv++) {
138 		if (priv->map->base_pwm_number + priv->map->num_channel_ios > hwpwm)
139 			break;
140 	}
141 
142 	return priv;
143 }
144 
rz_mtu3_pwm_is_ch_enabled(struct rz_mtu3_pwm_chip * rz_mtu3_pwm,u32 hwpwm)145 static bool rz_mtu3_pwm_is_ch_enabled(struct rz_mtu3_pwm_chip *rz_mtu3_pwm,
146 				      u32 hwpwm)
147 {
148 	struct rz_mtu3_pwm_channel *priv;
149 	bool is_channel_en;
150 	u8 val;
151 
152 	priv = rz_mtu3_get_channel(rz_mtu3_pwm, hwpwm);
153 	is_channel_en = rz_mtu3_is_enabled(priv->mtu);
154 	if (!is_channel_en)
155 		return false;
156 
157 	if (priv->map->base_pwm_number == hwpwm)
158 		val = rz_mtu3_8bit_ch_read(priv->mtu, RZ_MTU3_TIORH);
159 	else
160 		val = rz_mtu3_8bit_ch_read(priv->mtu, RZ_MTU3_TIORL);
161 
162 	return val & RZ_MTU3_TIOR_IOA;
163 }
164 
rz_mtu3_pwm_request(struct pwm_chip * chip,struct pwm_device * pwm)165 static int rz_mtu3_pwm_request(struct pwm_chip *chip, struct pwm_device *pwm)
166 {
167 	struct rz_mtu3_pwm_chip *rz_mtu3_pwm = to_rz_mtu3_pwm_chip(chip);
168 	struct rz_mtu3_pwm_channel *priv;
169 	bool is_mtu3_channel_available;
170 	u32 ch;
171 
172 	priv = rz_mtu3_get_channel(rz_mtu3_pwm, pwm->hwpwm);
173 	ch = priv - rz_mtu3_pwm->channel_data;
174 
175 	mutex_lock(&rz_mtu3_pwm->lock);
176 	/*
177 	 * Each channel must be requested only once, so if the channel
178 	 * serves two PWMs and the other is already requested, skip over
179 	 * rz_mtu3_request_channel()
180 	 */
181 	if (!rz_mtu3_pwm->user_count[ch]) {
182 		is_mtu3_channel_available = rz_mtu3_request_channel(priv->mtu);
183 		if (!is_mtu3_channel_available) {
184 			mutex_unlock(&rz_mtu3_pwm->lock);
185 			return -EBUSY;
186 		}
187 	}
188 
189 	rz_mtu3_pwm->user_count[ch]++;
190 	mutex_unlock(&rz_mtu3_pwm->lock);
191 
192 	return 0;
193 }
194 
rz_mtu3_pwm_free(struct pwm_chip * chip,struct pwm_device * pwm)195 static void rz_mtu3_pwm_free(struct pwm_chip *chip, struct pwm_device *pwm)
196 {
197 	struct rz_mtu3_pwm_chip *rz_mtu3_pwm = to_rz_mtu3_pwm_chip(chip);
198 	struct rz_mtu3_pwm_channel *priv;
199 	u32 ch;
200 
201 	priv = rz_mtu3_get_channel(rz_mtu3_pwm, pwm->hwpwm);
202 	ch = priv - rz_mtu3_pwm->channel_data;
203 
204 	mutex_lock(&rz_mtu3_pwm->lock);
205 	rz_mtu3_pwm->user_count[ch]--;
206 	if (!rz_mtu3_pwm->user_count[ch])
207 		rz_mtu3_release_channel(priv->mtu);
208 
209 	mutex_unlock(&rz_mtu3_pwm->lock);
210 }
211 
rz_mtu3_pwm_enable(struct pwm_chip * chip,struct pwm_device * pwm)212 static int rz_mtu3_pwm_enable(struct pwm_chip *chip, struct pwm_device *pwm)
213 {
214 	struct rz_mtu3_pwm_chip *rz_mtu3_pwm = to_rz_mtu3_pwm_chip(chip);
215 	struct rz_mtu3_pwm_channel *priv;
216 	u32 ch;
217 	u8 val;
218 	int rc;
219 
220 	rc = pm_runtime_resume_and_get(pwmchip_parent(chip));
221 	if (rc)
222 		return rc;
223 
224 	priv = rz_mtu3_get_channel(rz_mtu3_pwm, pwm->hwpwm);
225 	ch = priv - rz_mtu3_pwm->channel_data;
226 	val = RZ_MTU3_TIOR_OC_IOB_TOGGLE | RZ_MTU3_TIOR_OC_IOA_H_COMP_MATCH;
227 
228 	rz_mtu3_8bit_ch_write(priv->mtu, RZ_MTU3_TMDR1, RZ_MTU3_TMDR1_MD_PWMMODE1);
229 	if (priv->map->base_pwm_number == pwm->hwpwm)
230 		rz_mtu3_8bit_ch_write(priv->mtu, RZ_MTU3_TIORH, val);
231 	else
232 		rz_mtu3_8bit_ch_write(priv->mtu, RZ_MTU3_TIORL, val);
233 
234 	mutex_lock(&rz_mtu3_pwm->lock);
235 	if (!rz_mtu3_pwm->enable_count[ch])
236 		rz_mtu3_enable(priv->mtu);
237 
238 	rz_mtu3_pwm->enable_count[ch]++;
239 	mutex_unlock(&rz_mtu3_pwm->lock);
240 
241 	return 0;
242 }
243 
rz_mtu3_pwm_disable(struct pwm_chip * chip,struct pwm_device * pwm)244 static void rz_mtu3_pwm_disable(struct pwm_chip *chip, struct pwm_device *pwm)
245 {
246 	struct rz_mtu3_pwm_chip *rz_mtu3_pwm = to_rz_mtu3_pwm_chip(chip);
247 	struct rz_mtu3_pwm_channel *priv;
248 	u32 ch;
249 
250 	priv = rz_mtu3_get_channel(rz_mtu3_pwm, pwm->hwpwm);
251 	ch = priv - rz_mtu3_pwm->channel_data;
252 
253 	/* Disable output pins of MTU3 channel */
254 	if (priv->map->base_pwm_number == pwm->hwpwm)
255 		rz_mtu3_8bit_ch_write(priv->mtu, RZ_MTU3_TIORH, RZ_MTU3_TIOR_OC_RETAIN);
256 	else
257 		rz_mtu3_8bit_ch_write(priv->mtu, RZ_MTU3_TIORL, RZ_MTU3_TIOR_OC_RETAIN);
258 
259 	mutex_lock(&rz_mtu3_pwm->lock);
260 	rz_mtu3_pwm->enable_count[ch]--;
261 	if (!rz_mtu3_pwm->enable_count[ch])
262 		rz_mtu3_disable(priv->mtu);
263 
264 	mutex_unlock(&rz_mtu3_pwm->lock);
265 
266 	pm_runtime_put_sync(pwmchip_parent(chip));
267 }
268 
rz_mtu3_pwm_get_state(struct pwm_chip * chip,struct pwm_device * pwm,struct pwm_state * state)269 static int rz_mtu3_pwm_get_state(struct pwm_chip *chip, struct pwm_device *pwm,
270 				 struct pwm_state *state)
271 {
272 	struct rz_mtu3_pwm_chip *rz_mtu3_pwm = to_rz_mtu3_pwm_chip(chip);
273 	int rc;
274 
275 	rc = pm_runtime_resume_and_get(pwmchip_parent(chip));
276 	if (rc)
277 		return rc;
278 
279 	state->enabled = rz_mtu3_pwm_is_ch_enabled(rz_mtu3_pwm, pwm->hwpwm);
280 	if (state->enabled) {
281 		struct rz_mtu3_pwm_channel *priv;
282 		u8 prescale, val;
283 		u16 dc, pv;
284 		u64 tmp;
285 
286 		priv = rz_mtu3_get_channel(rz_mtu3_pwm, pwm->hwpwm);
287 		if (priv->map->base_pwm_number == pwm->hwpwm)
288 			rz_mtu3_pwm_read_tgr_registers(priv, RZ_MTU3_TGRA, &pv,
289 						       RZ_MTU3_TGRB, &dc);
290 		else
291 			rz_mtu3_pwm_read_tgr_registers(priv, RZ_MTU3_TGRC, &pv,
292 						       RZ_MTU3_TGRD, &dc);
293 
294 		val = rz_mtu3_8bit_ch_read(priv->mtu, RZ_MTU3_TCR);
295 		prescale = FIELD_GET(RZ_MTU3_TCR_TPCS, val);
296 
297 		/* With prescale <= 7 and pv <= 0xffff this doesn't overflow. */
298 		tmp = NSEC_PER_SEC * (u64)pv << (2 * prescale);
299 		state->period = DIV_ROUND_UP_ULL(tmp, rz_mtu3_pwm->rate);
300 		tmp = NSEC_PER_SEC * (u64)dc << (2 * prescale);
301 		state->duty_cycle = DIV_ROUND_UP_ULL(tmp, rz_mtu3_pwm->rate);
302 
303 		if (state->duty_cycle > state->period)
304 			state->duty_cycle = state->period;
305 	}
306 
307 	state->polarity = PWM_POLARITY_NORMAL;
308 	pm_runtime_put(pwmchip_parent(chip));
309 
310 	return 0;
311 }
312 
rz_mtu3_pwm_calculate_pv_or_dc(u64 period_or_duty_cycle,u8 prescale)313 static u16 rz_mtu3_pwm_calculate_pv_or_dc(u64 period_or_duty_cycle, u8 prescale)
314 {
315 	return min(period_or_duty_cycle >> (2 * prescale), (u64)U16_MAX);
316 }
317 
rz_mtu3_pwm_config(struct pwm_chip * chip,struct pwm_device * pwm,const struct pwm_state * state)318 static int rz_mtu3_pwm_config(struct pwm_chip *chip, struct pwm_device *pwm,
319 			      const struct pwm_state *state)
320 {
321 	struct rz_mtu3_pwm_chip *rz_mtu3_pwm = to_rz_mtu3_pwm_chip(chip);
322 	struct rz_mtu3_pwm_channel *priv;
323 	u64 period_cycles;
324 	u64 duty_cycles;
325 	u8 prescale;
326 	u16 pv, dc;
327 	u8 val;
328 	u32 ch;
329 
330 	priv = rz_mtu3_get_channel(rz_mtu3_pwm, pwm->hwpwm);
331 	ch = priv - rz_mtu3_pwm->channel_data;
332 
333 	period_cycles = mul_u64_u32_div(state->period, rz_mtu3_pwm->rate,
334 					NSEC_PER_SEC);
335 	prescale = rz_mtu3_pwm_calculate_prescale(rz_mtu3_pwm, period_cycles);
336 
337 	/*
338 	 * Prescalar is shared by multiple channels, so prescale can
339 	 * NOT be modified when there are multiple channels in use with
340 	 * different settings. Modify prescalar if other PWM is off or handle
341 	 * it, if current prescale value is less than the one we want to set.
342 	 */
343 	if (rz_mtu3_pwm->enable_count[ch] > 1) {
344 		if (rz_mtu3_pwm->prescale[ch] > prescale)
345 			return -EBUSY;
346 
347 		prescale = rz_mtu3_pwm->prescale[ch];
348 	}
349 
350 	pv = rz_mtu3_pwm_calculate_pv_or_dc(period_cycles, prescale);
351 
352 	duty_cycles = mul_u64_u32_div(state->duty_cycle, rz_mtu3_pwm->rate,
353 				      NSEC_PER_SEC);
354 	dc = rz_mtu3_pwm_calculate_pv_or_dc(duty_cycles, prescale);
355 
356 	/*
357 	 * If the PWM channel is disabled, make sure to turn on the clock
358 	 * before writing the register.
359 	 */
360 	if (!pwm->state.enabled) {
361 		int rc;
362 
363 		rc = pm_runtime_resume_and_get(pwmchip_parent(chip));
364 		if (rc)
365 			return rc;
366 	}
367 
368 	val = RZ_MTU3_TCR_CKEG_RISING | prescale;
369 
370 	/* Counter must be stopped while updating TCR register */
371 	if (rz_mtu3_pwm->prescale[ch] != prescale && rz_mtu3_pwm->enable_count[ch])
372 		rz_mtu3_disable(priv->mtu);
373 
374 	if (priv->map->base_pwm_number == pwm->hwpwm) {
375 		rz_mtu3_8bit_ch_write(priv->mtu, RZ_MTU3_TCR,
376 				      RZ_MTU3_TCR_CCLR_TGRA | val);
377 		rz_mtu3_pwm_write_tgr_registers(priv, RZ_MTU3_TGRA, pv,
378 						RZ_MTU3_TGRB, dc);
379 	} else {
380 		rz_mtu3_8bit_ch_write(priv->mtu, RZ_MTU3_TCR,
381 				      RZ_MTU3_TCR_CCLR_TGRC | val);
382 		rz_mtu3_pwm_write_tgr_registers(priv, RZ_MTU3_TGRC, pv,
383 						RZ_MTU3_TGRD, dc);
384 	}
385 
386 	if (rz_mtu3_pwm->prescale[ch] != prescale) {
387 		/*
388 		 * Prescalar is shared by multiple channels, we cache the
389 		 * prescalar value from first enabled channel and use the same
390 		 * value for both channels.
391 		 */
392 		rz_mtu3_pwm->prescale[ch] = prescale;
393 
394 		if (rz_mtu3_pwm->enable_count[ch])
395 			rz_mtu3_enable(priv->mtu);
396 	}
397 
398 	/* If the PWM is not enabled, turn the clock off again to save power. */
399 	if (!pwm->state.enabled)
400 		pm_runtime_put(pwmchip_parent(chip));
401 
402 	return 0;
403 }
404 
rz_mtu3_pwm_apply(struct pwm_chip * chip,struct pwm_device * pwm,const struct pwm_state * state)405 static int rz_mtu3_pwm_apply(struct pwm_chip *chip, struct pwm_device *pwm,
406 			     const struct pwm_state *state)
407 {
408 	struct rz_mtu3_pwm_chip *rz_mtu3_pwm = to_rz_mtu3_pwm_chip(chip);
409 	bool enabled = pwm->state.enabled;
410 	int ret;
411 
412 	if (state->polarity != PWM_POLARITY_NORMAL)
413 		return -EINVAL;
414 
415 	if (!state->enabled) {
416 		if (enabled)
417 			rz_mtu3_pwm_disable(chip, pwm);
418 
419 		return 0;
420 	}
421 
422 	mutex_lock(&rz_mtu3_pwm->lock);
423 	ret = rz_mtu3_pwm_config(chip, pwm, state);
424 	mutex_unlock(&rz_mtu3_pwm->lock);
425 	if (ret)
426 		return ret;
427 
428 	if (!enabled)
429 		ret = rz_mtu3_pwm_enable(chip, pwm);
430 
431 	return ret;
432 }
433 
434 static const struct pwm_ops rz_mtu3_pwm_ops = {
435 	.request = rz_mtu3_pwm_request,
436 	.free = rz_mtu3_pwm_free,
437 	.get_state = rz_mtu3_pwm_get_state,
438 	.apply = rz_mtu3_pwm_apply,
439 };
440 
rz_mtu3_pwm_pm_runtime_suspend(struct device * dev)441 static int rz_mtu3_pwm_pm_runtime_suspend(struct device *dev)
442 {
443 	struct pwm_chip *chip = dev_get_drvdata(dev);
444 	struct rz_mtu3_pwm_chip *rz_mtu3_pwm = to_rz_mtu3_pwm_chip(chip);
445 
446 	clk_disable_unprepare(rz_mtu3_pwm->clk);
447 
448 	return 0;
449 }
450 
rz_mtu3_pwm_pm_runtime_resume(struct device * dev)451 static int rz_mtu3_pwm_pm_runtime_resume(struct device *dev)
452 {
453 	struct pwm_chip *chip = dev_get_drvdata(dev);
454 	struct rz_mtu3_pwm_chip *rz_mtu3_pwm = to_rz_mtu3_pwm_chip(chip);
455 
456 	return clk_prepare_enable(rz_mtu3_pwm->clk);
457 }
458 
459 static DEFINE_RUNTIME_DEV_PM_OPS(rz_mtu3_pwm_pm_ops,
460 				 rz_mtu3_pwm_pm_runtime_suspend,
461 				 rz_mtu3_pwm_pm_runtime_resume, NULL);
462 
rz_mtu3_pwm_pm_disable(void * data)463 static void rz_mtu3_pwm_pm_disable(void *data)
464 {
465 	struct pwm_chip *chip = data;
466 	struct rz_mtu3_pwm_chip *rz_mtu3_pwm = to_rz_mtu3_pwm_chip(chip);
467 
468 	clk_rate_exclusive_put(rz_mtu3_pwm->clk);
469 	pm_runtime_disable(pwmchip_parent(chip));
470 	pm_runtime_set_suspended(pwmchip_parent(chip));
471 }
472 
rz_mtu3_pwm_probe(struct platform_device * pdev)473 static int rz_mtu3_pwm_probe(struct platform_device *pdev)
474 {
475 	struct rz_mtu3 *parent_ddata = dev_get_drvdata(pdev->dev.parent);
476 	struct rz_mtu3_pwm_chip *rz_mtu3_pwm;
477 	struct pwm_chip *chip;
478 	struct device *dev = &pdev->dev;
479 	unsigned int i, j = 0;
480 	int ret;
481 
482 	chip = devm_pwmchip_alloc(&pdev->dev, RZ_MTU3_MAX_PWM_CHANNELS,
483 				  sizeof(*rz_mtu3_pwm));
484 	if (IS_ERR(chip))
485 		return PTR_ERR(chip);
486 	rz_mtu3_pwm = to_rz_mtu3_pwm_chip(chip);
487 
488 	rz_mtu3_pwm->clk = parent_ddata->clk;
489 
490 	for (i = 0; i < RZ_MTU_NUM_CHANNELS; i++) {
491 		if (i == RZ_MTU3_CHAN_5 || i == RZ_MTU3_CHAN_8)
492 			continue;
493 
494 		rz_mtu3_pwm->channel_data[j].mtu = &parent_ddata->channels[i];
495 		rz_mtu3_pwm->channel_data[j].mtu->dev = dev;
496 		rz_mtu3_pwm->channel_data[j].map = &channel_map[j];
497 		j++;
498 	}
499 
500 	mutex_init(&rz_mtu3_pwm->lock);
501 	platform_set_drvdata(pdev, chip);
502 	ret = clk_prepare_enable(rz_mtu3_pwm->clk);
503 	if (ret)
504 		return dev_err_probe(dev, ret, "Clock enable failed\n");
505 
506 	clk_rate_exclusive_get(rz_mtu3_pwm->clk);
507 
508 	rz_mtu3_pwm->rate = clk_get_rate(rz_mtu3_pwm->clk);
509 	/*
510 	 * Refuse clk rates > 1 GHz to prevent overflow later for computing
511 	 * period and duty cycle.
512 	 */
513 	if (rz_mtu3_pwm->rate > NSEC_PER_SEC) {
514 		ret = -EINVAL;
515 		clk_rate_exclusive_put(rz_mtu3_pwm->clk);
516 		goto disable_clock;
517 	}
518 
519 	pm_runtime_set_active(&pdev->dev);
520 	pm_runtime_enable(&pdev->dev);
521 	ret = devm_add_action_or_reset(&pdev->dev, rz_mtu3_pwm_pm_disable,
522 				       chip);
523 	if (ret < 0)
524 		return ret;
525 
526 	chip->ops = &rz_mtu3_pwm_ops;
527 	ret = devm_pwmchip_add(&pdev->dev, chip);
528 	if (ret)
529 		return dev_err_probe(&pdev->dev, ret, "failed to add PWM chip\n");
530 
531 	pm_runtime_idle(&pdev->dev);
532 
533 	return 0;
534 
535 disable_clock:
536 	clk_disable_unprepare(rz_mtu3_pwm->clk);
537 	return ret;
538 }
539 
540 static struct platform_driver rz_mtu3_pwm_driver = {
541 	.driver = {
542 		.name = "pwm-rz-mtu3",
543 		.pm = pm_ptr(&rz_mtu3_pwm_pm_ops),
544 	},
545 	.probe = rz_mtu3_pwm_probe,
546 };
547 module_platform_driver(rz_mtu3_pwm_driver);
548 
549 MODULE_AUTHOR("Biju Das <biju.das.jz@bp.renesas.com>");
550 MODULE_ALIAS("platform:pwm-rz-mtu3");
551 MODULE_DESCRIPTION("Renesas RZ/G2L MTU3a PWM Timer Driver");
552 MODULE_LICENSE("GPL");
553