xref: /OK3568_Linux_fs/kernel/drivers/pwm/pwm-rockchip.c (revision 4882a59341e53eb6f0b4789bf948001014eff981)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * PWM driver for Rockchip SoCs
4  *
5  * Copyright (C) 2014 Beniamino Galvani <b.galvani@gmail.com>
6  * Copyright (C) 2014 ROCKCHIP, Inc.
7  */
8 
9 #include <linux/clk.h>
10 #include <linux/interrupt.h>
11 #include <linux/io.h>
12 #include <linux/iopoll.h>
13 #include <linux/irq.h>
14 #include <linux/module.h>
15 #include <linux/of.h>
16 #include <linux/of_device.h>
17 #include <linux/pinctrl/consumer.h>
18 #include <linux/platform_device.h>
19 #include <linux/pwm.h>
20 #include <linux/time.h>
21 #include "pwm-rockchip.h"
22 
23 #define PWM_MAX_CHANNEL_NUM	4
24 
25 #define PWM_CTRL_TIMER_EN	(1 << 0)
26 #define PWM_CTRL_OUTPUT_EN	(1 << 3)
27 
28 #define PWM_ENABLE		(1 << 0)
29 #define PWM_MODE_SHIFT		1
30 #define PWM_MODE_MASK		(0x3 << PWM_MODE_SHIFT)
31 #define PWM_ONESHOT		(0 << PWM_MODE_SHIFT)
32 #define PWM_CONTINUOUS		(1 << PWM_MODE_SHIFT)
33 #define PWM_CAPTURE		(2 << PWM_MODE_SHIFT)
34 #define PWM_DUTY_POSITIVE	(1 << 3)
35 #define PWM_DUTY_NEGATIVE	(0 << 3)
36 #define PWM_INACTIVE_NEGATIVE	(0 << 4)
37 #define PWM_INACTIVE_POSITIVE	(1 << 4)
38 #define PWM_POLARITY_MASK	(PWM_DUTY_POSITIVE | PWM_INACTIVE_POSITIVE)
39 #define PWM_OUTPUT_LEFT		(0 << 5)
40 #define PWM_OUTPUT_CENTER	(1 << 5)
41 #define PWM_LOCK_EN		(1 << 6)
42 #define PWM_LP_DISABLE		(0 << 8)
43 #define PWM_CLK_SEL_SHIFT	9
44 #define PWM_CLK_SEL_MASK	(1 << PWM_CLK_SEL_SHIFT)
45 #define PWM_SEL_NO_SCALED_CLOCK	(0 << PWM_CLK_SEL_SHIFT)
46 #define PWM_SEL_SCALED_CLOCK	(1 << PWM_CLK_SEL_SHIFT)
47 #define PWM_PRESCELE_SHIFT	12
48 #define PWM_PRESCALE_MASK	(0x3 << PWM_PRESCELE_SHIFT)
49 #define PWM_SCALE_SHIFT		16
50 #define PWM_SCALE_MASK		(0xff << PWM_SCALE_SHIFT)
51 
52 #define PWM_ONESHOT_COUNT_SHIFT	24
53 #define PWM_ONESHOT_COUNT_MASK	(0xff << PWM_ONESHOT_COUNT_SHIFT)
54 #define PWM_ONESHOT_COUNT_MAX	256
55 
56 #define PWM_REG_INTSTS(n)	((3 - (n)) * 0x10 + 0x10)
57 #define PWM_REG_INT_EN(n)	((3 - (n)) * 0x10 + 0x14)
58 
59 #define PWM_CH_INT(n)		BIT(n)
60 
61 struct rockchip_pwm_chip {
62 	struct pwm_chip chip;
63 	struct clk *clk;
64 	struct clk *pclk;
65 	struct pinctrl *pinctrl;
66 	struct pinctrl_state *active_state;
67 	const struct rockchip_pwm_data *data;
68 	void __iomem *base;
69 	unsigned long clk_rate;
70 	bool vop_pwm_en; /* indicate voppwm mirror register state */
71 	bool center_aligned;
72 	bool oneshot_en;
73 	int channel_id;
74 	int irq;
75 };
76 
77 struct rockchip_pwm_regs {
78 	unsigned long duty;
79 	unsigned long period;
80 	unsigned long cntr;
81 	unsigned long ctrl;
82 };
83 
84 struct rockchip_pwm_data {
85 	struct rockchip_pwm_regs regs;
86 	unsigned int prescaler;
87 	bool supports_polarity;
88 	bool supports_lock;
89 	bool vop_pwm;
90 	u32 enable_conf;
91 	u32 enable_conf_mask;
92 };
93 
to_rockchip_pwm_chip(struct pwm_chip * c)94 static inline struct rockchip_pwm_chip *to_rockchip_pwm_chip(struct pwm_chip *c)
95 {
96 	return container_of(c, struct rockchip_pwm_chip, chip);
97 }
98 
rockchip_pwm_get_state(struct pwm_chip * chip,struct pwm_device * pwm,struct pwm_state * state)99 static void rockchip_pwm_get_state(struct pwm_chip *chip,
100 				   struct pwm_device *pwm,
101 				   struct pwm_state *state)
102 {
103 	struct rockchip_pwm_chip *pc = to_rockchip_pwm_chip(chip);
104 	u32 enable_conf = pc->data->enable_conf;
105 	u64 tmp;
106 	u32 val;
107 	u32 dclk_div;
108 	int ret;
109 
110 	if (!pc->oneshot_en) {
111 		ret = clk_enable(pc->pclk);
112 		if (ret)
113 			return;
114 	}
115 
116 	dclk_div = pc->oneshot_en ? 2 : 1;
117 
118 	tmp = readl_relaxed(pc->base + pc->data->regs.period);
119 	tmp *= dclk_div * pc->data->prescaler * NSEC_PER_SEC;
120 	state->period = DIV_ROUND_CLOSEST_ULL(tmp, pc->clk_rate);
121 
122 	tmp = readl_relaxed(pc->base + pc->data->regs.duty);
123 	tmp *= dclk_div * pc->data->prescaler * NSEC_PER_SEC;
124 	state->duty_cycle =  DIV_ROUND_CLOSEST_ULL(tmp, pc->clk_rate);
125 
126 	val = readl_relaxed(pc->base + pc->data->regs.ctrl);
127 	if (pc->oneshot_en)
128 		enable_conf &= ~PWM_CONTINUOUS;
129 	state->enabled = (val & enable_conf) == enable_conf;
130 
131 	if (pc->data->supports_polarity && !(val & PWM_DUTY_POSITIVE))
132 		state->polarity = PWM_POLARITY_INVERSED;
133 	else
134 		state->polarity = PWM_POLARITY_NORMAL;
135 
136 	if (!pc->oneshot_en)
137 		clk_disable(pc->pclk);
138 }
139 
rockchip_pwm_oneshot_irq(int irq,void * data)140 static irqreturn_t rockchip_pwm_oneshot_irq(int irq, void *data)
141 {
142 	struct rockchip_pwm_chip *pc = data;
143 	struct pwm_state state;
144 	unsigned int id = pc->channel_id;
145 	int val;
146 
147 	if (id > 3)
148 		return IRQ_NONE;
149 	val = readl_relaxed(pc->base + PWM_REG_INTSTS(id));
150 
151 	if ((val & PWM_CH_INT(id)) == 0)
152 		return IRQ_NONE;
153 
154 	writel_relaxed(PWM_CH_INT(id), pc->base + PWM_REG_INTSTS(id));
155 
156 	/*
157 	 * Set pwm state to disabled when the oneshot mode finished.
158 	 */
159 	pwm_get_state(&pc->chip.pwms[0], &state);
160 	state.enabled = false;
161 	pwm_apply_state(&pc->chip.pwms[0], &state);
162 
163 	rockchip_pwm_oneshot_callback(&pc->chip.pwms[0], &state);
164 
165 	return IRQ_HANDLED;
166 }
167 
rockchip_pwm_config(struct pwm_chip * chip,struct pwm_device * pwm,const struct pwm_state * state)168 static void rockchip_pwm_config(struct pwm_chip *chip, struct pwm_device *pwm,
169 			       const struct pwm_state *state)
170 {
171 	struct rockchip_pwm_chip *pc = to_rockchip_pwm_chip(chip);
172 	unsigned long period, duty;
173 	unsigned long flags;
174 	u64 div;
175 	u32 ctrl;
176 	u8 dclk_div = 1;
177 
178 #ifdef CONFIG_PWM_ROCKCHIP_ONESHOT
179 	if (state->oneshot_count > 0 && state->oneshot_count <= PWM_ONESHOT_COUNT_MAX)
180 		dclk_div = 2;
181 #endif
182 
183 	/*
184 	 * Since period and duty cycle registers have a width of 32
185 	 * bits, every possible input period can be obtained using the
186 	 * default prescaler value for all practical clock rate values.
187 	 */
188 	div = (u64)pc->clk_rate * state->period;
189 	period = DIV_ROUND_CLOSEST_ULL(div, dclk_div * pc->data->prescaler * NSEC_PER_SEC);
190 
191 	div = (u64)pc->clk_rate * state->duty_cycle;
192 	duty = DIV_ROUND_CLOSEST_ULL(div, dclk_div * pc->data->prescaler * NSEC_PER_SEC);
193 
194 	local_irq_save(flags);
195 	/*
196 	 * Lock the period and duty of previous configuration, then
197 	 * change the duty and period, that would not be effective.
198 	 */
199 	ctrl = readl_relaxed(pc->base + pc->data->regs.ctrl);
200 	if (pc->data->vop_pwm) {
201 		if (pc->vop_pwm_en)
202 			ctrl |= PWM_ENABLE;
203 		else
204 			ctrl &= ~PWM_ENABLE;
205 	}
206 
207 #ifdef CONFIG_PWM_ROCKCHIP_ONESHOT
208 	if (state->oneshot_count > 0 && state->oneshot_count <= PWM_ONESHOT_COUNT_MAX) {
209 		u32 int_ctrl;
210 
211 		/*
212 		 * This is a workaround, an uncertain waveform will be
213 		 * generated after oneshot ends. It is needed to enable
214 		 * the dclk scale function to resolve it. It doesn't
215 		 * matter what the scale factor is, just make sure the
216 		 * scale function is turned on, for which we set scale
217 		 * factor to 2.
218 		 */
219 		ctrl &= ~PWM_SCALE_MASK;
220 		ctrl |= (dclk_div / 2) << PWM_SCALE_SHIFT;
221 		ctrl &= ~PWM_CLK_SEL_MASK;
222 		ctrl |= PWM_SEL_SCALED_CLOCK;
223 
224 		pc->oneshot_en = true;
225 		ctrl &= ~PWM_MODE_MASK;
226 		ctrl |= PWM_ONESHOT;
227 
228 		ctrl &= ~PWM_ONESHOT_COUNT_MASK;
229 		ctrl |= (state->oneshot_count - 1) << PWM_ONESHOT_COUNT_SHIFT;
230 
231 		int_ctrl = readl_relaxed(pc->base + PWM_REG_INT_EN(pc->channel_id));
232 		int_ctrl |= PWM_CH_INT(pc->channel_id);
233 		writel_relaxed(int_ctrl, pc->base + PWM_REG_INT_EN(pc->channel_id));
234 	} else {
235 		u32 int_ctrl;
236 
237 		ctrl &= ~PWM_SCALE_MASK;
238 		ctrl &= ~PWM_CLK_SEL_MASK;
239 		ctrl |= PWM_SEL_NO_SCALED_CLOCK;
240 
241 		if (state->oneshot_count)
242 			dev_err(chip->dev, "Oneshot_count must be between 1 and 256.\n");
243 
244 		pc->oneshot_en = false;
245 		ctrl &= ~PWM_MODE_MASK;
246 		ctrl |= PWM_CONTINUOUS;
247 
248 		ctrl &= ~PWM_ONESHOT_COUNT_MASK;
249 
250 		int_ctrl = readl_relaxed(pc->base + PWM_REG_INT_EN(pc->channel_id));
251 		int_ctrl &= ~PWM_CH_INT(pc->channel_id);
252 		writel_relaxed(int_ctrl, pc->base + PWM_REG_INT_EN(pc->channel_id));
253 	}
254 #endif
255 
256 	if (pc->data->supports_lock) {
257 		ctrl |= PWM_LOCK_EN;
258 		writel_relaxed(ctrl, pc->base + pc->data->regs.ctrl);
259 	}
260 
261 	writel(period, pc->base + pc->data->regs.period);
262 	writel(duty, pc->base + pc->data->regs.duty);
263 
264 	if (pc->data->supports_polarity) {
265 		ctrl &= ~PWM_POLARITY_MASK;
266 		if (state->polarity == PWM_POLARITY_INVERSED)
267 			ctrl |= PWM_DUTY_NEGATIVE | PWM_INACTIVE_POSITIVE;
268 		else
269 			ctrl |= PWM_DUTY_POSITIVE | PWM_INACTIVE_NEGATIVE;
270 	}
271 
272 	/*
273 	 * Unlock and set polarity at the same time,
274 	 * the configuration of duty, period and polarity
275 	 * would be effective together at next period.
276 	 */
277 	if (pc->data->supports_lock)
278 		ctrl &= ~PWM_LOCK_EN;
279 
280 	writel(ctrl, pc->base + pc->data->regs.ctrl);
281 	local_irq_restore(flags);
282 }
283 
rockchip_pwm_enable(struct pwm_chip * chip,struct pwm_device * pwm,bool enable)284 static int rockchip_pwm_enable(struct pwm_chip *chip,
285 			       struct pwm_device *pwm,
286 			       bool enable)
287 {
288 	struct rockchip_pwm_chip *pc = to_rockchip_pwm_chip(chip);
289 	u32 enable_conf = pc->data->enable_conf;
290 	int ret;
291 	u32 val;
292 
293 	if (enable) {
294 		ret = clk_enable(pc->clk);
295 		if (ret)
296 			return ret;
297 	}
298 
299 	val = readl_relaxed(pc->base + pc->data->regs.ctrl);
300 	val &= ~pc->data->enable_conf_mask;
301 
302 	if (PWM_OUTPUT_CENTER & pc->data->enable_conf_mask) {
303 		if (pc->center_aligned)
304 			val |= PWM_OUTPUT_CENTER;
305 	}
306 
307 	if (enable) {
308 		val |= enable_conf;
309 		if (pc->oneshot_en)
310 			val &= ~PWM_CONTINUOUS;
311 	} else {
312 		val &= ~enable_conf;
313 	}
314 
315 	writel_relaxed(val, pc->base + pc->data->regs.ctrl);
316 	if (pc->data->vop_pwm)
317 		pc->vop_pwm_en = enable;
318 
319 	if (!enable)
320 		clk_disable(pc->clk);
321 
322 	return 0;
323 }
324 
rockchip_pwm_apply(struct pwm_chip * chip,struct pwm_device * pwm,const struct pwm_state * state)325 static int rockchip_pwm_apply(struct pwm_chip *chip, struct pwm_device *pwm,
326 			      const struct pwm_state *state)
327 {
328 	struct rockchip_pwm_chip *pc = to_rockchip_pwm_chip(chip);
329 	struct pwm_state curstate;
330 	bool enabled;
331 	int ret = 0;
332 
333 	if (!pc->oneshot_en) {
334 		ret = clk_enable(pc->pclk);
335 		if (ret)
336 			return ret;
337 	}
338 
339 	pwm_get_state(pwm, &curstate);
340 	enabled = curstate.enabled;
341 
342 	if (state->polarity != curstate.polarity && enabled &&
343 	    !pc->data->supports_lock) {
344 		ret = rockchip_pwm_enable(chip, pwm, false);
345 		if (ret)
346 			goto out;
347 		enabled = false;
348 	}
349 
350 	rockchip_pwm_config(chip, pwm, state);
351 	if (state->enabled != enabled) {
352 		ret = rockchip_pwm_enable(chip, pwm, state->enabled);
353 		if (ret)
354 			goto out;
355 	}
356 
357 	if (state->enabled)
358 		ret = pinctrl_select_state(pc->pinctrl, pc->active_state);
359 out:
360 	if (!pc->oneshot_en)
361 		clk_disable(pc->pclk);
362 
363 	return ret;
364 }
365 
366 static const struct pwm_ops rockchip_pwm_ops = {
367 	.get_state = rockchip_pwm_get_state,
368 	.apply = rockchip_pwm_apply,
369 	.owner = THIS_MODULE,
370 };
371 
372 static const struct rockchip_pwm_data pwm_data_v1 = {
373 	.regs = {
374 		.duty = 0x04,
375 		.period = 0x08,
376 		.cntr = 0x00,
377 		.ctrl = 0x0c,
378 	},
379 	.prescaler = 2,
380 	.supports_polarity = false,
381 	.supports_lock = false,
382 	.vop_pwm = false,
383 	.enable_conf = PWM_CTRL_OUTPUT_EN | PWM_CTRL_TIMER_EN,
384 	.enable_conf_mask = BIT(1) | BIT(3),
385 };
386 
387 static const struct rockchip_pwm_data pwm_data_v2 = {
388 	.regs = {
389 		.duty = 0x08,
390 		.period = 0x04,
391 		.cntr = 0x00,
392 		.ctrl = 0x0c,
393 	},
394 	.prescaler = 1,
395 	.supports_polarity = true,
396 	.supports_lock = false,
397 	.vop_pwm = false,
398 	.enable_conf = PWM_OUTPUT_LEFT | PWM_LP_DISABLE | PWM_ENABLE |
399 		       PWM_CONTINUOUS,
400 	.enable_conf_mask = GENMASK(2, 0) | BIT(5) | BIT(8),
401 };
402 
403 static const struct rockchip_pwm_data pwm_data_vop = {
404 	.regs = {
405 		.duty = 0x08,
406 		.period = 0x04,
407 		.cntr = 0x0c,
408 		.ctrl = 0x00,
409 	},
410 	.prescaler = 1,
411 	.supports_polarity = true,
412 	.supports_lock = false,
413 	.vop_pwm = true,
414 	.enable_conf = PWM_OUTPUT_LEFT | PWM_LP_DISABLE | PWM_ENABLE |
415 		       PWM_CONTINUOUS,
416 	.enable_conf_mask = GENMASK(2, 0) | BIT(5) | BIT(8),
417 };
418 
419 static const struct rockchip_pwm_data pwm_data_v3 = {
420 	.regs = {
421 		.duty = 0x08,
422 		.period = 0x04,
423 		.cntr = 0x00,
424 		.ctrl = 0x0c,
425 	},
426 	.prescaler = 1,
427 	.supports_polarity = true,
428 	.supports_lock = true,
429 	.vop_pwm = false,
430 	.enable_conf = PWM_OUTPUT_LEFT | PWM_LP_DISABLE | PWM_ENABLE |
431 		       PWM_CONTINUOUS,
432 	.enable_conf_mask = GENMASK(2, 0) | BIT(5) | BIT(8),
433 };
434 
435 static const struct of_device_id rockchip_pwm_dt_ids[] = {
436 	{ .compatible = "rockchip,rk2928-pwm", .data = &pwm_data_v1},
437 	{ .compatible = "rockchip,rk3288-pwm", .data = &pwm_data_v2},
438 	{ .compatible = "rockchip,vop-pwm", .data = &pwm_data_vop},
439 	{ .compatible = "rockchip,rk3328-pwm", .data = &pwm_data_v3},
440 	{ /* sentinel */ }
441 };
442 MODULE_DEVICE_TABLE(of, rockchip_pwm_dt_ids);
443 
rockchip_pwm_get_channel_id(const char * name)444 static int rockchip_pwm_get_channel_id(const char *name)
445 {
446 	int len = strlen(name);
447 
448 	return name[len - 2] - '0';
449 }
450 
rockchip_pwm_probe(struct platform_device * pdev)451 static int rockchip_pwm_probe(struct platform_device *pdev)
452 {
453 	const struct of_device_id *id;
454 	struct rockchip_pwm_chip *pc;
455 	struct resource *r;
456 	u32 enable_conf, ctrl;
457 	bool enabled;
458 	int ret, count;
459 
460 	id = of_match_device(rockchip_pwm_dt_ids, &pdev->dev);
461 	if (!id)
462 		return -EINVAL;
463 
464 	pc = devm_kzalloc(&pdev->dev, sizeof(*pc), GFP_KERNEL);
465 	if (!pc)
466 		return -ENOMEM;
467 
468 	r = platform_get_resource(pdev, IORESOURCE_MEM, 0);
469 	pc->base = devm_ioremap(&pdev->dev, r->start,
470 				resource_size(r));
471 	if (IS_ERR(pc->base))
472 		return PTR_ERR(pc->base);
473 
474 	pc->clk = devm_clk_get(&pdev->dev, "pwm");
475 	if (IS_ERR(pc->clk)) {
476 		pc->clk = devm_clk_get(&pdev->dev, NULL);
477 		if (IS_ERR(pc->clk))
478 			return dev_err_probe(&pdev->dev, PTR_ERR(pc->clk),
479 					     "Can't get bus clk\n");
480 	}
481 
482 	count = of_count_phandle_with_args(pdev->dev.of_node,
483 					   "clocks", "#clock-cells");
484 	if (count == 2)
485 		pc->pclk = devm_clk_get(&pdev->dev, "pclk");
486 	else
487 		pc->pclk = pc->clk;
488 
489 	if (IS_ERR(pc->pclk)) {
490 		ret = PTR_ERR(pc->pclk);
491 		if (ret != -EPROBE_DEFER)
492 			dev_err(&pdev->dev, "Can't get APB clk: %d\n", ret);
493 		return ret;
494 	}
495 
496 	ret = clk_prepare_enable(pc->clk);
497 	if (ret) {
498 		dev_err(&pdev->dev, "Can't prepare enable bus clk: %d\n", ret);
499 		return ret;
500 	}
501 
502 	ret = clk_prepare_enable(pc->pclk);
503 	if (ret) {
504 		dev_err(&pdev->dev, "Can't prepare enable APB clk: %d\n", ret);
505 		goto err_clk;
506 	}
507 
508 	pc->channel_id = rockchip_pwm_get_channel_id(pdev->dev.of_node->full_name);
509 	if (pc->channel_id < 0 || pc->channel_id >= PWM_MAX_CHANNEL_NUM) {
510 		dev_err(&pdev->dev, "Channel id is out of range: %d\n", pc->channel_id);
511 		ret = -EINVAL;
512 		goto err_pclk;
513 	}
514 
515 	if (IS_ENABLED(CONFIG_PWM_ROCKCHIP_ONESHOT)) {
516 		pc->irq = platform_get_irq(pdev, 0);
517 		if (pc->irq < 0) {
518 			dev_err(&pdev->dev, "Get oneshot mode irq failed\n");
519 			ret = pc->irq;
520 			goto err_pclk;
521 		}
522 
523 		ret = devm_request_irq(&pdev->dev, pc->irq, rockchip_pwm_oneshot_irq,
524 				       IRQF_NO_SUSPEND | IRQF_SHARED,
525 				       "rk_pwm_oneshot_irq", pc);
526 		if (ret) {
527 			dev_err(&pdev->dev, "Claim oneshot IRQ failed\n");
528 			goto err_pclk;
529 		}
530 	}
531 
532 	pc->pinctrl = devm_pinctrl_get(&pdev->dev);
533 	if (IS_ERR(pc->pinctrl)) {
534 		dev_err(&pdev->dev, "Get pinctrl failed!\n");
535 		ret = PTR_ERR(pc->pinctrl);
536 		goto err_pclk;
537 	}
538 
539 	pc->active_state = pinctrl_lookup_state(pc->pinctrl, "active");
540 	if (IS_ERR(pc->active_state)) {
541 		dev_err(&pdev->dev, "No active pinctrl state\n");
542 		ret = PTR_ERR(pc->active_state);
543 		goto err_pclk;
544 	}
545 
546 	platform_set_drvdata(pdev, pc);
547 
548 	pc->data = id->data;
549 	pc->chip.dev = &pdev->dev;
550 	pc->chip.ops = &rockchip_pwm_ops;
551 	pc->chip.base = of_alias_get_id(pdev->dev.of_node, "pwm");
552 	pc->chip.npwm = 1;
553 	pc->clk_rate = clk_get_rate(pc->clk);
554 
555 	if (pc->data->supports_polarity) {
556 		pc->chip.of_xlate = of_pwm_xlate_with_flags;
557 		pc->chip.of_pwm_n_cells = 3;
558 	}
559 
560 	enable_conf = pc->data->enable_conf;
561 	ctrl = readl_relaxed(pc->base + pc->data->regs.ctrl);
562 	enabled = (ctrl & enable_conf) == enable_conf;
563 
564 	pc->center_aligned =
565 		device_property_read_bool(&pdev->dev, "center-aligned");
566 
567 	ret = pwmchip_add(&pc->chip);
568 	if (ret < 0) {
569 		dev_err(&pdev->dev, "pwmchip_add() failed: %d\n", ret);
570 		goto err_pclk;
571 	}
572 
573 	/* Keep the PWM clk enabled if the PWM appears to be up and running. */
574 	if (!enabled)
575 		clk_disable(pc->clk);
576 
577 	clk_disable(pc->pclk);
578 
579 	return 0;
580 
581 err_pclk:
582 	clk_disable_unprepare(pc->pclk);
583 err_clk:
584 	clk_disable_unprepare(pc->clk);
585 
586 	return ret;
587 }
588 
rockchip_pwm_remove(struct platform_device * pdev)589 static int rockchip_pwm_remove(struct platform_device *pdev)
590 {
591 	struct rockchip_pwm_chip *pc = platform_get_drvdata(pdev);
592 	struct pwm_state state;
593 	u32 val;
594 
595 	/*
596 	 * For oneshot mode, it is needed to wait for bit PWM_ENABLE
597 	 * to 0, which is automatic if all periods have been sent.
598 	 */
599 	pwm_get_state(&pc->chip.pwms[0], &state);
600 	if (state.enabled) {
601 		if (pc->oneshot_en) {
602 			if (readl_poll_timeout(pc->base + pc->data->regs.ctrl,
603 					       val, !(val & PWM_ENABLE), 1000, 10 * 1000))
604 				dev_err(&pdev->dev, "Wait for oneshot to complete failed\n");
605 		} else {
606 			state.enabled = false;
607 			pwm_apply_state(&pc->chip.pwms[0], &state);
608 		}
609 	}
610 
611 	if (pc->oneshot_en)
612 		clk_disable(pc->pclk);
613 	clk_unprepare(pc->pclk);
614 	clk_unprepare(pc->clk);
615 
616 	return pwmchip_remove(&pc->chip);
617 }
618 
619 static struct platform_driver rockchip_pwm_driver = {
620 	.driver = {
621 		.name = "rockchip-pwm",
622 		.of_match_table = rockchip_pwm_dt_ids,
623 	},
624 	.probe = rockchip_pwm_probe,
625 	.remove = rockchip_pwm_remove,
626 };
627 #ifdef CONFIG_ROCKCHIP_THUNDER_BOOT
rockchip_pwm_driver_init(void)628 static int __init rockchip_pwm_driver_init(void)
629 {
630 	return platform_driver_register(&rockchip_pwm_driver);
631 }
632 subsys_initcall(rockchip_pwm_driver_init);
633 
rockchip_pwm_driver_exit(void)634 static void __exit rockchip_pwm_driver_exit(void)
635 {
636 	platform_driver_unregister(&rockchip_pwm_driver);
637 }
638 module_exit(rockchip_pwm_driver_exit);
639 #else
640 module_platform_driver(rockchip_pwm_driver);
641 #endif
642 
643 MODULE_AUTHOR("Beniamino Galvani <b.galvani@gmail.com>");
644 MODULE_DESCRIPTION("Rockchip SoC PWM driver");
645 MODULE_LICENSE("GPL v2");
646