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v6.8
  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/io.h>
 11#include <linux/module.h>
 12#include <linux/of.h>
 
 13#include <linux/platform_device.h>
 14#include <linux/property.h>
 15#include <linux/pwm.h>
 16#include <linux/time.h>
 17
 18#define PWM_CTRL_TIMER_EN	(1 << 0)
 19#define PWM_CTRL_OUTPUT_EN	(1 << 3)
 20
 21#define PWM_ENABLE		(1 << 0)
 22#define PWM_CONTINUOUS		(1 << 1)
 23#define PWM_DUTY_POSITIVE	(1 << 3)
 24#define PWM_DUTY_NEGATIVE	(0 << 3)
 25#define PWM_INACTIVE_NEGATIVE	(0 << 4)
 26#define PWM_INACTIVE_POSITIVE	(1 << 4)
 27#define PWM_POLARITY_MASK	(PWM_DUTY_POSITIVE | PWM_INACTIVE_POSITIVE)
 28#define PWM_OUTPUT_LEFT		(0 << 5)
 29#define PWM_LOCK_EN		(1 << 6)
 30#define PWM_LP_DISABLE		(0 << 8)
 31
 32struct rockchip_pwm_chip {
 33	struct pwm_chip chip;
 34	struct clk *clk;
 35	struct clk *pclk;
 36	const struct rockchip_pwm_data *data;
 37	void __iomem *base;
 38};
 39
 40struct rockchip_pwm_regs {
 41	unsigned long duty;
 42	unsigned long period;
 43	unsigned long cntr;
 44	unsigned long ctrl;
 45};
 46
 47struct rockchip_pwm_data {
 48	struct rockchip_pwm_regs regs;
 49	unsigned int prescaler;
 50	bool supports_polarity;
 51	bool supports_lock;
 52	u32 enable_conf;
 53};
 54
 55static inline struct rockchip_pwm_chip *to_rockchip_pwm_chip(struct pwm_chip *chip)
 56{
 57	return container_of(chip, struct rockchip_pwm_chip, chip);
 58}
 59
 60static int rockchip_pwm_get_state(struct pwm_chip *chip,
 61				  struct pwm_device *pwm,
 62				  struct pwm_state *state)
 63{
 64	struct rockchip_pwm_chip *pc = to_rockchip_pwm_chip(chip);
 65	u32 enable_conf = pc->data->enable_conf;
 66	unsigned long clk_rate;
 67	u64 tmp;
 68	u32 val;
 69	int ret;
 70
 71	ret = clk_enable(pc->pclk);
 72	if (ret)
 73		return ret;
 74
 75	ret = clk_enable(pc->clk);
 76	if (ret)
 77		return ret;
 78
 79	clk_rate = clk_get_rate(pc->clk);
 80
 81	tmp = readl_relaxed(pc->base + pc->data->regs.period);
 82	tmp *= pc->data->prescaler * NSEC_PER_SEC;
 83	state->period = DIV_ROUND_CLOSEST_ULL(tmp, clk_rate);
 84
 85	tmp = readl_relaxed(pc->base + pc->data->regs.duty);
 86	tmp *= pc->data->prescaler * NSEC_PER_SEC;
 87	state->duty_cycle =  DIV_ROUND_CLOSEST_ULL(tmp, clk_rate);
 88
 89	val = readl_relaxed(pc->base + pc->data->regs.ctrl);
 90	state->enabled = (val & enable_conf) == enable_conf;
 91
 92	if (pc->data->supports_polarity && !(val & PWM_DUTY_POSITIVE))
 93		state->polarity = PWM_POLARITY_INVERSED;
 94	else
 95		state->polarity = PWM_POLARITY_NORMAL;
 96
 97	clk_disable(pc->clk);
 98	clk_disable(pc->pclk);
 99
100	return 0;
101}
102
103static void rockchip_pwm_config(struct pwm_chip *chip, struct pwm_device *pwm,
104			       const struct pwm_state *state)
105{
106	struct rockchip_pwm_chip *pc = to_rockchip_pwm_chip(chip);
107	unsigned long period, duty;
108	u64 clk_rate, div;
109	u32 ctrl;
110
111	clk_rate = clk_get_rate(pc->clk);
112
113	/*
114	 * Since period and duty cycle registers have a width of 32
115	 * bits, every possible input period can be obtained using the
116	 * default prescaler value for all practical clock rate values.
117	 */
118	div = clk_rate * state->period;
119	period = DIV_ROUND_CLOSEST_ULL(div,
120				       pc->data->prescaler * NSEC_PER_SEC);
121
122	div = clk_rate * state->duty_cycle;
123	duty = DIV_ROUND_CLOSEST_ULL(div, pc->data->prescaler * NSEC_PER_SEC);
124
125	/*
126	 * Lock the period and duty of previous configuration, then
127	 * change the duty and period, that would not be effective.
128	 */
129	ctrl = readl_relaxed(pc->base + pc->data->regs.ctrl);
130	if (pc->data->supports_lock) {
131		ctrl |= PWM_LOCK_EN;
132		writel_relaxed(ctrl, pc->base + pc->data->regs.ctrl);
133	}
134
135	writel(period, pc->base + pc->data->regs.period);
136	writel(duty, pc->base + pc->data->regs.duty);
137
138	if (pc->data->supports_polarity) {
139		ctrl &= ~PWM_POLARITY_MASK;
140		if (state->polarity == PWM_POLARITY_INVERSED)
141			ctrl |= PWM_DUTY_NEGATIVE | PWM_INACTIVE_POSITIVE;
142		else
143			ctrl |= PWM_DUTY_POSITIVE | PWM_INACTIVE_NEGATIVE;
144	}
145
146	/*
147	 * Unlock and set polarity at the same time,
148	 * the configuration of duty, period and polarity
149	 * would be effective together at next period.
150	 */
151	if (pc->data->supports_lock)
152		ctrl &= ~PWM_LOCK_EN;
153
154	writel(ctrl, pc->base + pc->data->regs.ctrl);
155}
156
157static int rockchip_pwm_enable(struct pwm_chip *chip,
158			       struct pwm_device *pwm,
159			       bool enable)
160{
161	struct rockchip_pwm_chip *pc = to_rockchip_pwm_chip(chip);
162	u32 enable_conf = pc->data->enable_conf;
163	int ret;
164	u32 val;
165
166	if (enable) {
167		ret = clk_enable(pc->clk);
168		if (ret)
169			return ret;
170	}
171
172	val = readl_relaxed(pc->base + pc->data->regs.ctrl);
173
174	if (enable)
175		val |= enable_conf;
176	else
177		val &= ~enable_conf;
178
179	writel_relaxed(val, pc->base + pc->data->regs.ctrl);
180
181	if (!enable)
182		clk_disable(pc->clk);
183
184	return 0;
185}
186
187static int rockchip_pwm_apply(struct pwm_chip *chip, struct pwm_device *pwm,
188			      const struct pwm_state *state)
189{
190	struct rockchip_pwm_chip *pc = to_rockchip_pwm_chip(chip);
191	struct pwm_state curstate;
192	bool enabled;
193	int ret = 0;
194
195	ret = clk_enable(pc->pclk);
196	if (ret)
197		return ret;
198
199	ret = clk_enable(pc->clk);
200	if (ret)
201		return ret;
202
203	pwm_get_state(pwm, &curstate);
204	enabled = curstate.enabled;
205
206	if (state->polarity != curstate.polarity && enabled &&
207	    !pc->data->supports_lock) {
208		ret = rockchip_pwm_enable(chip, pwm, false);
209		if (ret)
210			goto out;
211		enabled = false;
212	}
213
214	rockchip_pwm_config(chip, pwm, state);
215	if (state->enabled != enabled) {
216		ret = rockchip_pwm_enable(chip, pwm, state->enabled);
217		if (ret)
218			goto out;
219	}
220
221out:
222	clk_disable(pc->clk);
223	clk_disable(pc->pclk);
224
225	return ret;
226}
227
228static const struct pwm_ops rockchip_pwm_ops = {
229	.get_state = rockchip_pwm_get_state,
230	.apply = rockchip_pwm_apply,
 
231};
232
233static const struct rockchip_pwm_data pwm_data_v1 = {
234	.regs = {
235		.duty = 0x04,
236		.period = 0x08,
237		.cntr = 0x00,
238		.ctrl = 0x0c,
239	},
240	.prescaler = 2,
241	.supports_polarity = false,
242	.supports_lock = false,
243	.enable_conf = PWM_CTRL_OUTPUT_EN | PWM_CTRL_TIMER_EN,
244};
245
246static const struct rockchip_pwm_data pwm_data_v2 = {
247	.regs = {
248		.duty = 0x08,
249		.period = 0x04,
250		.cntr = 0x00,
251		.ctrl = 0x0c,
252	},
253	.prescaler = 1,
254	.supports_polarity = true,
255	.supports_lock = false,
256	.enable_conf = PWM_OUTPUT_LEFT | PWM_LP_DISABLE | PWM_ENABLE |
257		       PWM_CONTINUOUS,
258};
259
260static const struct rockchip_pwm_data pwm_data_vop = {
261	.regs = {
262		.duty = 0x08,
263		.period = 0x04,
264		.cntr = 0x0c,
265		.ctrl = 0x00,
266	},
267	.prescaler = 1,
268	.supports_polarity = true,
269	.supports_lock = false,
270	.enable_conf = PWM_OUTPUT_LEFT | PWM_LP_DISABLE | PWM_ENABLE |
271		       PWM_CONTINUOUS,
272};
273
274static const struct rockchip_pwm_data pwm_data_v3 = {
275	.regs = {
276		.duty = 0x08,
277		.period = 0x04,
278		.cntr = 0x00,
279		.ctrl = 0x0c,
280	},
281	.prescaler = 1,
282	.supports_polarity = true,
283	.supports_lock = true,
284	.enable_conf = PWM_OUTPUT_LEFT | PWM_LP_DISABLE | PWM_ENABLE |
285		       PWM_CONTINUOUS,
286};
287
288static const struct of_device_id rockchip_pwm_dt_ids[] = {
289	{ .compatible = "rockchip,rk2928-pwm", .data = &pwm_data_v1},
290	{ .compatible = "rockchip,rk3288-pwm", .data = &pwm_data_v2},
291	{ .compatible = "rockchip,vop-pwm", .data = &pwm_data_vop},
292	{ .compatible = "rockchip,rk3328-pwm", .data = &pwm_data_v3},
293	{ /* sentinel */ }
294};
295MODULE_DEVICE_TABLE(of, rockchip_pwm_dt_ids);
296
297static int rockchip_pwm_probe(struct platform_device *pdev)
298{
 
299	struct rockchip_pwm_chip *pc;
300	u32 enable_conf, ctrl;
301	bool enabled;
302	int ret, count;
303
 
 
 
 
304	pc = devm_kzalloc(&pdev->dev, sizeof(*pc), GFP_KERNEL);
305	if (!pc)
306		return -ENOMEM;
307
308	pc->base = devm_platform_ioremap_resource(pdev, 0);
309	if (IS_ERR(pc->base))
310		return PTR_ERR(pc->base);
311
312	pc->clk = devm_clk_get(&pdev->dev, "pwm");
313	if (IS_ERR(pc->clk)) {
314		pc->clk = devm_clk_get(&pdev->dev, NULL);
315		if (IS_ERR(pc->clk))
316			return dev_err_probe(&pdev->dev, PTR_ERR(pc->clk),
317					     "Can't get PWM clk\n");
318	}
319
320	count = of_count_phandle_with_args(pdev->dev.of_node,
321					   "clocks", "#clock-cells");
322	if (count == 2)
323		pc->pclk = devm_clk_get(&pdev->dev, "pclk");
324	else
325		pc->pclk = pc->clk;
326
327	if (IS_ERR(pc->pclk))
328		return dev_err_probe(&pdev->dev, PTR_ERR(pc->pclk), "Can't get APB clk\n");
329
330	ret = clk_prepare_enable(pc->clk);
331	if (ret)
332		return dev_err_probe(&pdev->dev, ret, "Can't prepare enable PWM clk\n");
333
334	ret = clk_prepare_enable(pc->pclk);
335	if (ret) {
336		dev_err_probe(&pdev->dev, ret, "Can't prepare enable APB clk\n");
337		goto err_clk;
338	}
339
340	platform_set_drvdata(pdev, pc);
341
342	pc->data = device_get_match_data(&pdev->dev);
343	pc->chip.dev = &pdev->dev;
344	pc->chip.ops = &rockchip_pwm_ops;
345	pc->chip.npwm = 1;
346
347	enable_conf = pc->data->enable_conf;
348	ctrl = readl_relaxed(pc->base + pc->data->regs.ctrl);
349	enabled = (ctrl & enable_conf) == enable_conf;
350
351	ret = pwmchip_add(&pc->chip);
352	if (ret < 0) {
353		dev_err_probe(&pdev->dev, ret, "pwmchip_add() failed\n");
354		goto err_pclk;
355	}
356
357	/* Keep the PWM clk enabled if the PWM appears to be up and running. */
358	if (!enabled)
359		clk_disable(pc->clk);
360
361	clk_disable(pc->pclk);
362
363	return 0;
364
365err_pclk:
366	clk_disable_unprepare(pc->pclk);
367err_clk:
368	clk_disable_unprepare(pc->clk);
369
370	return ret;
371}
372
373static void rockchip_pwm_remove(struct platform_device *pdev)
374{
375	struct rockchip_pwm_chip *pc = platform_get_drvdata(pdev);
376
377	pwmchip_remove(&pc->chip);
378
379	clk_unprepare(pc->pclk);
380	clk_unprepare(pc->clk);
 
 
381}
382
383static struct platform_driver rockchip_pwm_driver = {
384	.driver = {
385		.name = "rockchip-pwm",
386		.of_match_table = rockchip_pwm_dt_ids,
387	},
388	.probe = rockchip_pwm_probe,
389	.remove_new = rockchip_pwm_remove,
390};
391module_platform_driver(rockchip_pwm_driver);
392
393MODULE_AUTHOR("Beniamino Galvani <b.galvani@gmail.com>");
394MODULE_DESCRIPTION("Rockchip SoC PWM driver");
395MODULE_LICENSE("GPL v2");
v6.2
  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/io.h>
 11#include <linux/module.h>
 12#include <linux/of.h>
 13#include <linux/of_device.h>
 14#include <linux/platform_device.h>
 
 15#include <linux/pwm.h>
 16#include <linux/time.h>
 17
 18#define PWM_CTRL_TIMER_EN	(1 << 0)
 19#define PWM_CTRL_OUTPUT_EN	(1 << 3)
 20
 21#define PWM_ENABLE		(1 << 0)
 22#define PWM_CONTINUOUS		(1 << 1)
 23#define PWM_DUTY_POSITIVE	(1 << 3)
 24#define PWM_DUTY_NEGATIVE	(0 << 3)
 25#define PWM_INACTIVE_NEGATIVE	(0 << 4)
 26#define PWM_INACTIVE_POSITIVE	(1 << 4)
 27#define PWM_POLARITY_MASK	(PWM_DUTY_POSITIVE | PWM_INACTIVE_POSITIVE)
 28#define PWM_OUTPUT_LEFT		(0 << 5)
 29#define PWM_LOCK_EN		(1 << 6)
 30#define PWM_LP_DISABLE		(0 << 8)
 31
 32struct rockchip_pwm_chip {
 33	struct pwm_chip chip;
 34	struct clk *clk;
 35	struct clk *pclk;
 36	const struct rockchip_pwm_data *data;
 37	void __iomem *base;
 38};
 39
 40struct rockchip_pwm_regs {
 41	unsigned long duty;
 42	unsigned long period;
 43	unsigned long cntr;
 44	unsigned long ctrl;
 45};
 46
 47struct rockchip_pwm_data {
 48	struct rockchip_pwm_regs regs;
 49	unsigned int prescaler;
 50	bool supports_polarity;
 51	bool supports_lock;
 52	u32 enable_conf;
 53};
 54
 55static inline struct rockchip_pwm_chip *to_rockchip_pwm_chip(struct pwm_chip *c)
 56{
 57	return container_of(c, struct rockchip_pwm_chip, chip);
 58}
 59
 60static int rockchip_pwm_get_state(struct pwm_chip *chip,
 61				  struct pwm_device *pwm,
 62				  struct pwm_state *state)
 63{
 64	struct rockchip_pwm_chip *pc = to_rockchip_pwm_chip(chip);
 65	u32 enable_conf = pc->data->enable_conf;
 66	unsigned long clk_rate;
 67	u64 tmp;
 68	u32 val;
 69	int ret;
 70
 71	ret = clk_enable(pc->pclk);
 72	if (ret)
 73		return ret;
 74
 75	ret = clk_enable(pc->clk);
 76	if (ret)
 77		return ret;
 78
 79	clk_rate = clk_get_rate(pc->clk);
 80
 81	tmp = readl_relaxed(pc->base + pc->data->regs.period);
 82	tmp *= pc->data->prescaler * NSEC_PER_SEC;
 83	state->period = DIV_ROUND_CLOSEST_ULL(tmp, clk_rate);
 84
 85	tmp = readl_relaxed(pc->base + pc->data->regs.duty);
 86	tmp *= pc->data->prescaler * NSEC_PER_SEC;
 87	state->duty_cycle =  DIV_ROUND_CLOSEST_ULL(tmp, clk_rate);
 88
 89	val = readl_relaxed(pc->base + pc->data->regs.ctrl);
 90	state->enabled = (val & enable_conf) == enable_conf;
 91
 92	if (pc->data->supports_polarity && !(val & PWM_DUTY_POSITIVE))
 93		state->polarity = PWM_POLARITY_INVERSED;
 94	else
 95		state->polarity = PWM_POLARITY_NORMAL;
 96
 97	clk_disable(pc->clk);
 98	clk_disable(pc->pclk);
 99
100	return 0;
101}
102
103static void rockchip_pwm_config(struct pwm_chip *chip, struct pwm_device *pwm,
104			       const struct pwm_state *state)
105{
106	struct rockchip_pwm_chip *pc = to_rockchip_pwm_chip(chip);
107	unsigned long period, duty;
108	u64 clk_rate, div;
109	u32 ctrl;
110
111	clk_rate = clk_get_rate(pc->clk);
112
113	/*
114	 * Since period and duty cycle registers have a width of 32
115	 * bits, every possible input period can be obtained using the
116	 * default prescaler value for all practical clock rate values.
117	 */
118	div = clk_rate * state->period;
119	period = DIV_ROUND_CLOSEST_ULL(div,
120				       pc->data->prescaler * NSEC_PER_SEC);
121
122	div = clk_rate * state->duty_cycle;
123	duty = DIV_ROUND_CLOSEST_ULL(div, pc->data->prescaler * NSEC_PER_SEC);
124
125	/*
126	 * Lock the period and duty of previous configuration, then
127	 * change the duty and period, that would not be effective.
128	 */
129	ctrl = readl_relaxed(pc->base + pc->data->regs.ctrl);
130	if (pc->data->supports_lock) {
131		ctrl |= PWM_LOCK_EN;
132		writel_relaxed(ctrl, pc->base + pc->data->regs.ctrl);
133	}
134
135	writel(period, pc->base + pc->data->regs.period);
136	writel(duty, pc->base + pc->data->regs.duty);
137
138	if (pc->data->supports_polarity) {
139		ctrl &= ~PWM_POLARITY_MASK;
140		if (state->polarity == PWM_POLARITY_INVERSED)
141			ctrl |= PWM_DUTY_NEGATIVE | PWM_INACTIVE_POSITIVE;
142		else
143			ctrl |= PWM_DUTY_POSITIVE | PWM_INACTIVE_NEGATIVE;
144	}
145
146	/*
147	 * Unlock and set polarity at the same time,
148	 * the configuration of duty, period and polarity
149	 * would be effective together at next period.
150	 */
151	if (pc->data->supports_lock)
152		ctrl &= ~PWM_LOCK_EN;
153
154	writel(ctrl, pc->base + pc->data->regs.ctrl);
155}
156
157static int rockchip_pwm_enable(struct pwm_chip *chip,
158			       struct pwm_device *pwm,
159			       bool enable)
160{
161	struct rockchip_pwm_chip *pc = to_rockchip_pwm_chip(chip);
162	u32 enable_conf = pc->data->enable_conf;
163	int ret;
164	u32 val;
165
166	if (enable) {
167		ret = clk_enable(pc->clk);
168		if (ret)
169			return ret;
170	}
171
172	val = readl_relaxed(pc->base + pc->data->regs.ctrl);
173
174	if (enable)
175		val |= enable_conf;
176	else
177		val &= ~enable_conf;
178
179	writel_relaxed(val, pc->base + pc->data->regs.ctrl);
180
181	if (!enable)
182		clk_disable(pc->clk);
183
184	return 0;
185}
186
187static int rockchip_pwm_apply(struct pwm_chip *chip, struct pwm_device *pwm,
188			      const struct pwm_state *state)
189{
190	struct rockchip_pwm_chip *pc = to_rockchip_pwm_chip(chip);
191	struct pwm_state curstate;
192	bool enabled;
193	int ret = 0;
194
195	ret = clk_enable(pc->pclk);
196	if (ret)
197		return ret;
198
199	ret = clk_enable(pc->clk);
200	if (ret)
201		return ret;
202
203	pwm_get_state(pwm, &curstate);
204	enabled = curstate.enabled;
205
206	if (state->polarity != curstate.polarity && enabled &&
207	    !pc->data->supports_lock) {
208		ret = rockchip_pwm_enable(chip, pwm, false);
209		if (ret)
210			goto out;
211		enabled = false;
212	}
213
214	rockchip_pwm_config(chip, pwm, state);
215	if (state->enabled != enabled) {
216		ret = rockchip_pwm_enable(chip, pwm, state->enabled);
217		if (ret)
218			goto out;
219	}
220
221out:
222	clk_disable(pc->clk);
223	clk_disable(pc->pclk);
224
225	return ret;
226}
227
228static const struct pwm_ops rockchip_pwm_ops = {
229	.get_state = rockchip_pwm_get_state,
230	.apply = rockchip_pwm_apply,
231	.owner = THIS_MODULE,
232};
233
234static const struct rockchip_pwm_data pwm_data_v1 = {
235	.regs = {
236		.duty = 0x04,
237		.period = 0x08,
238		.cntr = 0x00,
239		.ctrl = 0x0c,
240	},
241	.prescaler = 2,
242	.supports_polarity = false,
243	.supports_lock = false,
244	.enable_conf = PWM_CTRL_OUTPUT_EN | PWM_CTRL_TIMER_EN,
245};
246
247static const struct rockchip_pwm_data pwm_data_v2 = {
248	.regs = {
249		.duty = 0x08,
250		.period = 0x04,
251		.cntr = 0x00,
252		.ctrl = 0x0c,
253	},
254	.prescaler = 1,
255	.supports_polarity = true,
256	.supports_lock = false,
257	.enable_conf = PWM_OUTPUT_LEFT | PWM_LP_DISABLE | PWM_ENABLE |
258		       PWM_CONTINUOUS,
259};
260
261static const struct rockchip_pwm_data pwm_data_vop = {
262	.regs = {
263		.duty = 0x08,
264		.period = 0x04,
265		.cntr = 0x0c,
266		.ctrl = 0x00,
267	},
268	.prescaler = 1,
269	.supports_polarity = true,
270	.supports_lock = false,
271	.enable_conf = PWM_OUTPUT_LEFT | PWM_LP_DISABLE | PWM_ENABLE |
272		       PWM_CONTINUOUS,
273};
274
275static const struct rockchip_pwm_data pwm_data_v3 = {
276	.regs = {
277		.duty = 0x08,
278		.period = 0x04,
279		.cntr = 0x00,
280		.ctrl = 0x0c,
281	},
282	.prescaler = 1,
283	.supports_polarity = true,
284	.supports_lock = true,
285	.enable_conf = PWM_OUTPUT_LEFT | PWM_LP_DISABLE | PWM_ENABLE |
286		       PWM_CONTINUOUS,
287};
288
289static const struct of_device_id rockchip_pwm_dt_ids[] = {
290	{ .compatible = "rockchip,rk2928-pwm", .data = &pwm_data_v1},
291	{ .compatible = "rockchip,rk3288-pwm", .data = &pwm_data_v2},
292	{ .compatible = "rockchip,vop-pwm", .data = &pwm_data_vop},
293	{ .compatible = "rockchip,rk3328-pwm", .data = &pwm_data_v3},
294	{ /* sentinel */ }
295};
296MODULE_DEVICE_TABLE(of, rockchip_pwm_dt_ids);
297
298static int rockchip_pwm_probe(struct platform_device *pdev)
299{
300	const struct of_device_id *id;
301	struct rockchip_pwm_chip *pc;
302	u32 enable_conf, ctrl;
303	bool enabled;
304	int ret, count;
305
306	id = of_match_device(rockchip_pwm_dt_ids, &pdev->dev);
307	if (!id)
308		return -EINVAL;
309
310	pc = devm_kzalloc(&pdev->dev, sizeof(*pc), GFP_KERNEL);
311	if (!pc)
312		return -ENOMEM;
313
314	pc->base = devm_platform_ioremap_resource(pdev, 0);
315	if (IS_ERR(pc->base))
316		return PTR_ERR(pc->base);
317
318	pc->clk = devm_clk_get(&pdev->dev, "pwm");
319	if (IS_ERR(pc->clk)) {
320		pc->clk = devm_clk_get(&pdev->dev, NULL);
321		if (IS_ERR(pc->clk))
322			return dev_err_probe(&pdev->dev, PTR_ERR(pc->clk),
323					     "Can't get PWM clk\n");
324	}
325
326	count = of_count_phandle_with_args(pdev->dev.of_node,
327					   "clocks", "#clock-cells");
328	if (count == 2)
329		pc->pclk = devm_clk_get(&pdev->dev, "pclk");
330	else
331		pc->pclk = pc->clk;
332
333	if (IS_ERR(pc->pclk))
334		return dev_err_probe(&pdev->dev, PTR_ERR(pc->pclk), "Can't get APB clk\n");
335
336	ret = clk_prepare_enable(pc->clk);
337	if (ret)
338		return dev_err_probe(&pdev->dev, ret, "Can't prepare enable PWM clk\n");
339
340	ret = clk_prepare_enable(pc->pclk);
341	if (ret) {
342		dev_err_probe(&pdev->dev, ret, "Can't prepare enable APB clk\n");
343		goto err_clk;
344	}
345
346	platform_set_drvdata(pdev, pc);
347
348	pc->data = id->data;
349	pc->chip.dev = &pdev->dev;
350	pc->chip.ops = &rockchip_pwm_ops;
351	pc->chip.npwm = 1;
352
353	enable_conf = pc->data->enable_conf;
354	ctrl = readl_relaxed(pc->base + pc->data->regs.ctrl);
355	enabled = (ctrl & enable_conf) == enable_conf;
356
357	ret = pwmchip_add(&pc->chip);
358	if (ret < 0) {
359		dev_err_probe(&pdev->dev, ret, "pwmchip_add() failed\n");
360		goto err_pclk;
361	}
362
363	/* Keep the PWM clk enabled if the PWM appears to be up and running. */
364	if (!enabled)
365		clk_disable(pc->clk);
366
367	clk_disable(pc->pclk);
368
369	return 0;
370
371err_pclk:
372	clk_disable_unprepare(pc->pclk);
373err_clk:
374	clk_disable_unprepare(pc->clk);
375
376	return ret;
377}
378
379static int rockchip_pwm_remove(struct platform_device *pdev)
380{
381	struct rockchip_pwm_chip *pc = platform_get_drvdata(pdev);
382
383	pwmchip_remove(&pc->chip);
384
385	clk_unprepare(pc->pclk);
386	clk_unprepare(pc->clk);
387
388	return 0;
389}
390
391static struct platform_driver rockchip_pwm_driver = {
392	.driver = {
393		.name = "rockchip-pwm",
394		.of_match_table = rockchip_pwm_dt_ids,
395	},
396	.probe = rockchip_pwm_probe,
397	.remove = rockchip_pwm_remove,
398};
399module_platform_driver(rockchip_pwm_driver);
400
401MODULE_AUTHOR("Beniamino Galvani <b.galvani@gmail.com>");
402MODULE_DESCRIPTION("Rockchip SoC PWM driver");
403MODULE_LICENSE("GPL v2");