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v4.17
 
  1/*
  2 * EHRPWM PWM driver
  3 *
  4 * Copyright (C) 2012 Texas Instruments, Inc. - http://www.ti.com/
  5 *
  6 * This program is free software; you can redistribute it and/or modify
  7 * it under the terms of the GNU General Public License as published by
  8 * the Free Software Foundation; either version 2 of the License, or
  9 * (at your option) any later version.
 10 *
 11 * This program is distributed in the hope that it will be useful,
 12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
 14 * GNU General Public License for more details.
 15 *
 16 * You should have received a copy of the GNU General Public License
 17 * along with this program; if not, write to the Free Software
 18 * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
 19 */
 20
 21#include <linux/module.h>
 22#include <linux/platform_device.h>
 23#include <linux/pwm.h>
 24#include <linux/io.h>
 25#include <linux/err.h>
 26#include <linux/clk.h>
 27#include <linux/pm_runtime.h>
 28#include <linux/of_device.h>
 29
 30/* EHRPWM registers and bits definitions */
 31
 32/* Time base module registers */
 33#define TBCTL			0x00
 34#define TBPRD			0x0A
 35
 36#define TBCTL_RUN_MASK		(BIT(15) | BIT(14))
 37#define TBCTL_STOP_NEXT		0
 38#define TBCTL_STOP_ON_CYCLE	BIT(14)
 39#define TBCTL_FREE_RUN		(BIT(15) | BIT(14))
 40#define TBCTL_PRDLD_MASK	BIT(3)
 41#define TBCTL_PRDLD_SHDW	0
 42#define TBCTL_PRDLD_IMDT	BIT(3)
 43#define TBCTL_CLKDIV_MASK	(BIT(12) | BIT(11) | BIT(10) | BIT(9) | \
 44				BIT(8) | BIT(7))
 45#define TBCTL_CTRMODE_MASK	(BIT(1) | BIT(0))
 46#define TBCTL_CTRMODE_UP	0
 47#define TBCTL_CTRMODE_DOWN	BIT(0)
 48#define TBCTL_CTRMODE_UPDOWN	BIT(1)
 49#define TBCTL_CTRMODE_FREEZE	(BIT(1) | BIT(0))
 50
 51#define TBCTL_HSPCLKDIV_SHIFT	7
 52#define TBCTL_CLKDIV_SHIFT	10
 53
 54#define CLKDIV_MAX		7
 55#define HSPCLKDIV_MAX		7
 56#define PERIOD_MAX		0xFFFF
 57
 58/* compare module registers */
 59#define CMPA			0x12
 60#define CMPB			0x14
 61
 62/* Action qualifier module registers */
 63#define AQCTLA			0x16
 64#define AQCTLB			0x18
 65#define AQSFRC			0x1A
 66#define AQCSFRC			0x1C
 67
 68#define AQCTL_CBU_MASK		(BIT(9) | BIT(8))
 69#define AQCTL_CBU_FRCLOW	BIT(8)
 70#define AQCTL_CBU_FRCHIGH	BIT(9)
 71#define AQCTL_CBU_FRCTOGGLE	(BIT(9) | BIT(8))
 72#define AQCTL_CAU_MASK		(BIT(5) | BIT(4))
 73#define AQCTL_CAU_FRCLOW	BIT(4)
 74#define AQCTL_CAU_FRCHIGH	BIT(5)
 75#define AQCTL_CAU_FRCTOGGLE	(BIT(5) | BIT(4))
 76#define AQCTL_PRD_MASK		(BIT(3) | BIT(2))
 77#define AQCTL_PRD_FRCLOW	BIT(2)
 78#define AQCTL_PRD_FRCHIGH	BIT(3)
 79#define AQCTL_PRD_FRCTOGGLE	(BIT(3) | BIT(2))
 80#define AQCTL_ZRO_MASK		(BIT(1) | BIT(0))
 81#define AQCTL_ZRO_FRCLOW	BIT(0)
 82#define AQCTL_ZRO_FRCHIGH	BIT(1)
 83#define AQCTL_ZRO_FRCTOGGLE	(BIT(1) | BIT(0))
 84
 85#define AQCTL_CHANA_POLNORMAL	(AQCTL_CAU_FRCLOW | AQCTL_PRD_FRCHIGH | \
 86				AQCTL_ZRO_FRCHIGH)
 87#define AQCTL_CHANA_POLINVERSED	(AQCTL_CAU_FRCHIGH | AQCTL_PRD_FRCLOW | \
 88				AQCTL_ZRO_FRCLOW)
 89#define AQCTL_CHANB_POLNORMAL	(AQCTL_CBU_FRCLOW | AQCTL_PRD_FRCHIGH | \
 90				AQCTL_ZRO_FRCHIGH)
 91#define AQCTL_CHANB_POLINVERSED	(AQCTL_CBU_FRCHIGH | AQCTL_PRD_FRCLOW | \
 92				AQCTL_ZRO_FRCLOW)
 93
 94#define AQSFRC_RLDCSF_MASK	(BIT(7) | BIT(6))
 95#define AQSFRC_RLDCSF_ZRO	0
 96#define AQSFRC_RLDCSF_PRD	BIT(6)
 97#define AQSFRC_RLDCSF_ZROPRD	BIT(7)
 98#define AQSFRC_RLDCSF_IMDT	(BIT(7) | BIT(6))
 99
100#define AQCSFRC_CSFB_MASK	(BIT(3) | BIT(2))
101#define AQCSFRC_CSFB_FRCDIS	0
102#define AQCSFRC_CSFB_FRCLOW	BIT(2)
103#define AQCSFRC_CSFB_FRCHIGH	BIT(3)
104#define AQCSFRC_CSFB_DISSWFRC	(BIT(3) | BIT(2))
105#define AQCSFRC_CSFA_MASK	(BIT(1) | BIT(0))
106#define AQCSFRC_CSFA_FRCDIS	0
107#define AQCSFRC_CSFA_FRCLOW	BIT(0)
108#define AQCSFRC_CSFA_FRCHIGH	BIT(1)
109#define AQCSFRC_CSFA_DISSWFRC	(BIT(1) | BIT(0))
110
111#define NUM_PWM_CHANNEL		2	/* EHRPWM channels */
112
113struct ehrpwm_context {
114	u16 tbctl;
115	u16 tbprd;
116	u16 cmpa;
117	u16 cmpb;
118	u16 aqctla;
119	u16 aqctlb;
120	u16 aqsfrc;
121	u16 aqcsfrc;
122};
123
124struct ehrpwm_pwm_chip {
125	struct pwm_chip chip;
126	unsigned long clk_rate;
127	void __iomem *mmio_base;
128	unsigned long period_cycles[NUM_PWM_CHANNEL];
129	enum pwm_polarity polarity[NUM_PWM_CHANNEL];
130	struct clk *tbclk;
131	struct ehrpwm_context ctx;
132};
133
134static inline struct ehrpwm_pwm_chip *to_ehrpwm_pwm_chip(struct pwm_chip *chip)
135{
136	return container_of(chip, struct ehrpwm_pwm_chip, chip);
137}
138
139static inline u16 ehrpwm_read(void __iomem *base, unsigned int offset)
140{
141	return readw(base + offset);
142}
143
144static inline void ehrpwm_write(void __iomem *base, unsigned int offset,
145				u16 value)
146{
147	writew(value, base + offset);
148}
149
150static void ehrpwm_modify(void __iomem *base, unsigned int offset, u16 mask,
151			  u16 value)
152{
153	unsigned short val;
154
155	val = readw(base + offset);
156	val &= ~mask;
157	val |= value & mask;
158	writew(val, base + offset);
159}
160
161/**
162 * set_prescale_div -	Set up the prescaler divider function
163 * @rqst_prescaler:	prescaler value min
164 * @prescale_div:	prescaler value set
165 * @tb_clk_div:		Time Base Control prescaler bits
166 */
167static int set_prescale_div(unsigned long rqst_prescaler, u16 *prescale_div,
168			    u16 *tb_clk_div)
169{
170	unsigned int clkdiv, hspclkdiv;
171
172	for (clkdiv = 0; clkdiv <= CLKDIV_MAX; clkdiv++) {
173		for (hspclkdiv = 0; hspclkdiv <= HSPCLKDIV_MAX; hspclkdiv++) {
174			/*
175			 * calculations for prescaler value :
176			 * prescale_div = HSPCLKDIVIDER * CLKDIVIDER.
177			 * HSPCLKDIVIDER =  2 ** hspclkdiv
178			 * CLKDIVIDER = (1),		if clkdiv == 0 *OR*
179			 *		(2 * clkdiv),	if clkdiv != 0
180			 *
181			 * Configure prescale_div value such that period
182			 * register value is less than 65535.
183			 */
184
185			*prescale_div = (1 << clkdiv) *
186					(hspclkdiv ? (hspclkdiv * 2) : 1);
187			if (*prescale_div > rqst_prescaler) {
188				*tb_clk_div = (clkdiv << TBCTL_CLKDIV_SHIFT) |
189					(hspclkdiv << TBCTL_HSPCLKDIV_SHIFT);
190				return 0;
191			}
192		}
193	}
194
195	return 1;
196}
197
198static void configure_polarity(struct ehrpwm_pwm_chip *pc, int chan)
199{
200	u16 aqctl_val, aqctl_mask;
201	unsigned int aqctl_reg;
202
203	/*
204	 * Configure PWM output to HIGH/LOW level on counter
205	 * reaches compare register value and LOW/HIGH level
206	 * on counter value reaches period register value and
207	 * zero value on counter
208	 */
209	if (chan == 1) {
210		aqctl_reg = AQCTLB;
211		aqctl_mask = AQCTL_CBU_MASK;
212
213		if (pc->polarity[chan] == PWM_POLARITY_INVERSED)
214			aqctl_val = AQCTL_CHANB_POLINVERSED;
215		else
216			aqctl_val = AQCTL_CHANB_POLNORMAL;
217	} else {
218		aqctl_reg = AQCTLA;
219		aqctl_mask = AQCTL_CAU_MASK;
220
221		if (pc->polarity[chan] == PWM_POLARITY_INVERSED)
222			aqctl_val = AQCTL_CHANA_POLINVERSED;
223		else
224			aqctl_val = AQCTL_CHANA_POLNORMAL;
225	}
226
227	aqctl_mask |= AQCTL_PRD_MASK | AQCTL_ZRO_MASK;
228	ehrpwm_modify(pc->mmio_base, aqctl_reg, aqctl_mask, aqctl_val);
229}
230
231/*
232 * period_ns = 10^9 * (ps_divval * period_cycles) / PWM_CLK_RATE
233 * duty_ns   = 10^9 * (ps_divval * duty_cycles) / PWM_CLK_RATE
234 */
235static int ehrpwm_pwm_config(struct pwm_chip *chip, struct pwm_device *pwm,
236			     int duty_ns, int period_ns)
237{
238	struct ehrpwm_pwm_chip *pc = to_ehrpwm_pwm_chip(chip);
239	u32 period_cycles, duty_cycles;
240	u16 ps_divval, tb_divval;
241	unsigned int i, cmp_reg;
242	unsigned long long c;
243
244	if (period_ns > NSEC_PER_SEC)
245		return -ERANGE;
246
247	c = pc->clk_rate;
248	c = c * period_ns;
249	do_div(c, NSEC_PER_SEC);
250	period_cycles = (unsigned long)c;
251
252	if (period_cycles < 1) {
253		period_cycles = 1;
254		duty_cycles = 1;
255	} else {
256		c = pc->clk_rate;
257		c = c * duty_ns;
258		do_div(c, NSEC_PER_SEC);
259		duty_cycles = (unsigned long)c;
260	}
261
262	/*
263	 * Period values should be same for multiple PWM channels as IP uses
264	 * same period register for multiple channels.
265	 */
266	for (i = 0; i < NUM_PWM_CHANNEL; i++) {
267		if (pc->period_cycles[i] &&
268				(pc->period_cycles[i] != period_cycles)) {
269			/*
270			 * Allow channel to reconfigure period if no other
271			 * channels being configured.
272			 */
273			if (i == pwm->hwpwm)
274				continue;
275
276			dev_err(chip->dev,
277				"period value conflicts with channel %u\n",
278				i);
279			return -EINVAL;
280		}
281	}
282
283	pc->period_cycles[pwm->hwpwm] = period_cycles;
284
285	/* Configure clock prescaler to support Low frequency PWM wave */
286	if (set_prescale_div(period_cycles/PERIOD_MAX, &ps_divval,
287			     &tb_divval)) {
288		dev_err(chip->dev, "Unsupported values\n");
289		return -EINVAL;
290	}
291
292	pm_runtime_get_sync(chip->dev);
293
294	/* Update clock prescaler values */
295	ehrpwm_modify(pc->mmio_base, TBCTL, TBCTL_CLKDIV_MASK, tb_divval);
296
297	/* Update period & duty cycle with presacler division */
298	period_cycles = period_cycles / ps_divval;
299	duty_cycles = duty_cycles / ps_divval;
300
301	/* Configure shadow loading on Period register */
302	ehrpwm_modify(pc->mmio_base, TBCTL, TBCTL_PRDLD_MASK, TBCTL_PRDLD_SHDW);
303
304	ehrpwm_write(pc->mmio_base, TBPRD, period_cycles);
305
306	/* Configure ehrpwm counter for up-count mode */
307	ehrpwm_modify(pc->mmio_base, TBCTL, TBCTL_CTRMODE_MASK,
308		      TBCTL_CTRMODE_UP);
309
310	if (pwm->hwpwm == 1)
311		/* Channel 1 configured with compare B register */
312		cmp_reg = CMPB;
313	else
314		/* Channel 0 configured with compare A register */
315		cmp_reg = CMPA;
316
317	ehrpwm_write(pc->mmio_base, cmp_reg, duty_cycles);
318
319	pm_runtime_put_sync(chip->dev);
320
321	return 0;
322}
323
324static int ehrpwm_pwm_set_polarity(struct pwm_chip *chip,
325				   struct pwm_device *pwm,
326				   enum pwm_polarity polarity)
327{
328	struct ehrpwm_pwm_chip *pc = to_ehrpwm_pwm_chip(chip);
329
330	/* Configuration of polarity in hardware delayed, do at enable */
331	pc->polarity[pwm->hwpwm] = polarity;
332
333	return 0;
334}
335
336static int ehrpwm_pwm_enable(struct pwm_chip *chip, struct pwm_device *pwm)
337{
338	struct ehrpwm_pwm_chip *pc = to_ehrpwm_pwm_chip(chip);
339	u16 aqcsfrc_val, aqcsfrc_mask;
340	int ret;
341
342	/* Leave clock enabled on enabling PWM */
343	pm_runtime_get_sync(chip->dev);
344
345	/* Disabling Action Qualifier on PWM output */
346	if (pwm->hwpwm) {
347		aqcsfrc_val = AQCSFRC_CSFB_FRCDIS;
348		aqcsfrc_mask = AQCSFRC_CSFB_MASK;
349	} else {
350		aqcsfrc_val = AQCSFRC_CSFA_FRCDIS;
351		aqcsfrc_mask = AQCSFRC_CSFA_MASK;
352	}
353
354	/* Changes to shadow mode */
355	ehrpwm_modify(pc->mmio_base, AQSFRC, AQSFRC_RLDCSF_MASK,
356		      AQSFRC_RLDCSF_ZRO);
357
358	ehrpwm_modify(pc->mmio_base, AQCSFRC, aqcsfrc_mask, aqcsfrc_val);
359
360	/* Channels polarity can be configured from action qualifier module */
361	configure_polarity(pc, pwm->hwpwm);
362
363	/* Enable TBCLK before enabling PWM device */
364	ret = clk_enable(pc->tbclk);
365	if (ret) {
366		dev_err(chip->dev, "Failed to enable TBCLK for %s: %d\n",
367			dev_name(pc->chip.dev), ret);
368		return ret;
369	}
370
371	/* Enable time counter for free_run */
372	ehrpwm_modify(pc->mmio_base, TBCTL, TBCTL_RUN_MASK, TBCTL_FREE_RUN);
373
374	return 0;
375}
376
377static void ehrpwm_pwm_disable(struct pwm_chip *chip, struct pwm_device *pwm)
378{
379	struct ehrpwm_pwm_chip *pc = to_ehrpwm_pwm_chip(chip);
380	u16 aqcsfrc_val, aqcsfrc_mask;
381
382	/* Action Qualifier puts PWM output low forcefully */
383	if (pwm->hwpwm) {
384		aqcsfrc_val = AQCSFRC_CSFB_FRCLOW;
385		aqcsfrc_mask = AQCSFRC_CSFB_MASK;
386	} else {
387		aqcsfrc_val = AQCSFRC_CSFA_FRCLOW;
388		aqcsfrc_mask = AQCSFRC_CSFA_MASK;
389	}
390
 
 
 
 
391	/*
392	 * Changes to immediate action on Action Qualifier. This puts
393	 * Action Qualifier control on PWM output from next TBCLK
394	 */
395	ehrpwm_modify(pc->mmio_base, AQSFRC, AQSFRC_RLDCSF_MASK,
396		      AQSFRC_RLDCSF_IMDT);
397
398	ehrpwm_modify(pc->mmio_base, AQCSFRC, aqcsfrc_mask, aqcsfrc_val);
399
400	/* Disabling TBCLK on PWM disable */
401	clk_disable(pc->tbclk);
402
403	/* Stop Time base counter */
404	ehrpwm_modify(pc->mmio_base, TBCTL, TBCTL_RUN_MASK, TBCTL_STOP_NEXT);
405
406	/* Disable clock on PWM disable */
407	pm_runtime_put_sync(chip->dev);
408}
409
410static void ehrpwm_pwm_free(struct pwm_chip *chip, struct pwm_device *pwm)
411{
412	struct ehrpwm_pwm_chip *pc = to_ehrpwm_pwm_chip(chip);
413
414	if (pwm_is_enabled(pwm)) {
415		dev_warn(chip->dev, "Removing PWM device without disabling\n");
416		pm_runtime_put_sync(chip->dev);
417	}
418
419	/* set period value to zero on free */
420	pc->period_cycles[pwm->hwpwm] = 0;
421}
422
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
423static const struct pwm_ops ehrpwm_pwm_ops = {
424	.free = ehrpwm_pwm_free,
425	.config = ehrpwm_pwm_config,
426	.set_polarity = ehrpwm_pwm_set_polarity,
427	.enable = ehrpwm_pwm_enable,
428	.disable = ehrpwm_pwm_disable,
429	.owner = THIS_MODULE,
430};
431
432static const struct of_device_id ehrpwm_of_match[] = {
433	{ .compatible = "ti,am3352-ehrpwm" },
434	{ .compatible = "ti,am33xx-ehrpwm" },
435	{},
436};
437MODULE_DEVICE_TABLE(of, ehrpwm_of_match);
438
439static int ehrpwm_pwm_probe(struct platform_device *pdev)
440{
441	struct device_node *np = pdev->dev.of_node;
442	struct ehrpwm_pwm_chip *pc;
443	struct resource *r;
444	struct clk *clk;
445	int ret;
446
447	pc = devm_kzalloc(&pdev->dev, sizeof(*pc), GFP_KERNEL);
448	if (!pc)
449		return -ENOMEM;
450
451	clk = devm_clk_get(&pdev->dev, "fck");
452	if (IS_ERR(clk)) {
453		if (of_device_is_compatible(np, "ti,am33xx-ecap")) {
454			dev_warn(&pdev->dev, "Binding is obsolete.\n");
455			clk = devm_clk_get(pdev->dev.parent, "fck");
456		}
457	}
458
459	if (IS_ERR(clk)) {
460		dev_err(&pdev->dev, "failed to get clock\n");
461		return PTR_ERR(clk);
462	}
463
464	pc->clk_rate = clk_get_rate(clk);
465	if (!pc->clk_rate) {
466		dev_err(&pdev->dev, "failed to get clock rate\n");
467		return -EINVAL;
468	}
469
470	pc->chip.dev = &pdev->dev;
471	pc->chip.ops = &ehrpwm_pwm_ops;
472	pc->chip.of_xlate = of_pwm_xlate_with_flags;
473	pc->chip.of_pwm_n_cells = 3;
474	pc->chip.base = -1;
475	pc->chip.npwm = NUM_PWM_CHANNEL;
476
477	r = platform_get_resource(pdev, IORESOURCE_MEM, 0);
478	pc->mmio_base = devm_ioremap_resource(&pdev->dev, r);
479	if (IS_ERR(pc->mmio_base))
480		return PTR_ERR(pc->mmio_base);
481
482	/* Acquire tbclk for Time Base EHRPWM submodule */
483	pc->tbclk = devm_clk_get(&pdev->dev, "tbclk");
484	if (IS_ERR(pc->tbclk)) {
485		dev_err(&pdev->dev, "Failed to get tbclk\n");
486		return PTR_ERR(pc->tbclk);
487	}
488
489	ret = clk_prepare(pc->tbclk);
490	if (ret < 0) {
491		dev_err(&pdev->dev, "clk_prepare() failed: %d\n", ret);
492		return ret;
493	}
494
495	ret = pwmchip_add(&pc->chip);
496	if (ret < 0) {
497		dev_err(&pdev->dev, "pwmchip_add() failed: %d\n", ret);
498		goto err_clk_unprepare;
499	}
500
501	platform_set_drvdata(pdev, pc);
502	pm_runtime_enable(&pdev->dev);
503
504	return 0;
505
506err_clk_unprepare:
507	clk_unprepare(pc->tbclk);
508
509	return ret;
510}
511
512static int ehrpwm_pwm_remove(struct platform_device *pdev)
513{
514	struct ehrpwm_pwm_chip *pc = platform_get_drvdata(pdev);
515
 
 
516	clk_unprepare(pc->tbclk);
517
518	pm_runtime_disable(&pdev->dev);
519
520	return pwmchip_remove(&pc->chip);
521}
522
523#ifdef CONFIG_PM_SLEEP
524static void ehrpwm_pwm_save_context(struct ehrpwm_pwm_chip *pc)
525{
526	pm_runtime_get_sync(pc->chip.dev);
527
528	pc->ctx.tbctl = ehrpwm_read(pc->mmio_base, TBCTL);
529	pc->ctx.tbprd = ehrpwm_read(pc->mmio_base, TBPRD);
530	pc->ctx.cmpa = ehrpwm_read(pc->mmio_base, CMPA);
531	pc->ctx.cmpb = ehrpwm_read(pc->mmio_base, CMPB);
532	pc->ctx.aqctla = ehrpwm_read(pc->mmio_base, AQCTLA);
533	pc->ctx.aqctlb = ehrpwm_read(pc->mmio_base, AQCTLB);
534	pc->ctx.aqsfrc = ehrpwm_read(pc->mmio_base, AQSFRC);
535	pc->ctx.aqcsfrc = ehrpwm_read(pc->mmio_base, AQCSFRC);
536
537	pm_runtime_put_sync(pc->chip.dev);
538}
539
540static void ehrpwm_pwm_restore_context(struct ehrpwm_pwm_chip *pc)
541{
542	ehrpwm_write(pc->mmio_base, TBPRD, pc->ctx.tbprd);
543	ehrpwm_write(pc->mmio_base, CMPA, pc->ctx.cmpa);
544	ehrpwm_write(pc->mmio_base, CMPB, pc->ctx.cmpb);
545	ehrpwm_write(pc->mmio_base, AQCTLA, pc->ctx.aqctla);
546	ehrpwm_write(pc->mmio_base, AQCTLB, pc->ctx.aqctlb);
547	ehrpwm_write(pc->mmio_base, AQSFRC, pc->ctx.aqsfrc);
548	ehrpwm_write(pc->mmio_base, AQCSFRC, pc->ctx.aqcsfrc);
549	ehrpwm_write(pc->mmio_base, TBCTL, pc->ctx.tbctl);
550}
551
552static int ehrpwm_pwm_suspend(struct device *dev)
553{
554	struct ehrpwm_pwm_chip *pc = dev_get_drvdata(dev);
555	unsigned int i;
556
557	ehrpwm_pwm_save_context(pc);
558
559	for (i = 0; i < pc->chip.npwm; i++) {
560		struct pwm_device *pwm = &pc->chip.pwms[i];
561
562		if (!pwm_is_enabled(pwm))
563			continue;
564
565		/* Disable explicitly if PWM is running */
566		pm_runtime_put_sync(dev);
567	}
568
569	return 0;
570}
571
572static int ehrpwm_pwm_resume(struct device *dev)
573{
574	struct ehrpwm_pwm_chip *pc = dev_get_drvdata(dev);
575	unsigned int i;
576
577	for (i = 0; i < pc->chip.npwm; i++) {
578		struct pwm_device *pwm = &pc->chip.pwms[i];
579
580		if (!pwm_is_enabled(pwm))
581			continue;
582
583		/* Enable explicitly if PWM was running */
584		pm_runtime_get_sync(dev);
585	}
586
587	ehrpwm_pwm_restore_context(pc);
588
589	return 0;
590}
591#endif
592
593static SIMPLE_DEV_PM_OPS(ehrpwm_pwm_pm_ops, ehrpwm_pwm_suspend,
594			 ehrpwm_pwm_resume);
595
596static struct platform_driver ehrpwm_pwm_driver = {
597	.driver = {
598		.name = "ehrpwm",
599		.of_match_table = ehrpwm_of_match,
600		.pm = &ehrpwm_pwm_pm_ops,
601	},
602	.probe = ehrpwm_pwm_probe,
603	.remove = ehrpwm_pwm_remove,
604};
605module_platform_driver(ehrpwm_pwm_driver);
606
607MODULE_DESCRIPTION("EHRPWM PWM driver");
608MODULE_AUTHOR("Texas Instruments");
609MODULE_LICENSE("GPL");
v6.8
  1// SPDX-License-Identifier: GPL-2.0-or-later
  2/*
  3 * EHRPWM PWM driver
  4 *
  5 * Copyright (C) 2012 Texas Instruments, Inc. - https://www.ti.com/
 
 
 
 
 
 
 
 
 
 
 
 
 
 
  6 */
  7
  8#include <linux/module.h>
  9#include <linux/platform_device.h>
 10#include <linux/pwm.h>
 11#include <linux/io.h>
 12#include <linux/err.h>
 13#include <linux/clk.h>
 14#include <linux/pm_runtime.h>
 15#include <linux/of.h>
 16
 17/* EHRPWM registers and bits definitions */
 18
 19/* Time base module registers */
 20#define TBCTL			0x00
 21#define TBPRD			0x0A
 22
 
 
 
 
 23#define TBCTL_PRDLD_MASK	BIT(3)
 24#define TBCTL_PRDLD_SHDW	0
 25#define TBCTL_PRDLD_IMDT	BIT(3)
 26#define TBCTL_CLKDIV_MASK	(BIT(12) | BIT(11) | BIT(10) | BIT(9) | \
 27				BIT(8) | BIT(7))
 28#define TBCTL_CTRMODE_MASK	(BIT(1) | BIT(0))
 29#define TBCTL_CTRMODE_UP	0
 30#define TBCTL_CTRMODE_DOWN	BIT(0)
 31#define TBCTL_CTRMODE_UPDOWN	BIT(1)
 32#define TBCTL_CTRMODE_FREEZE	(BIT(1) | BIT(0))
 33
 34#define TBCTL_HSPCLKDIV_SHIFT	7
 35#define TBCTL_CLKDIV_SHIFT	10
 36
 37#define CLKDIV_MAX		7
 38#define HSPCLKDIV_MAX		7
 39#define PERIOD_MAX		0xFFFF
 40
 41/* compare module registers */
 42#define CMPA			0x12
 43#define CMPB			0x14
 44
 45/* Action qualifier module registers */
 46#define AQCTLA			0x16
 47#define AQCTLB			0x18
 48#define AQSFRC			0x1A
 49#define AQCSFRC			0x1C
 50
 51#define AQCTL_CBU_MASK		(BIT(9) | BIT(8))
 52#define AQCTL_CBU_FRCLOW	BIT(8)
 53#define AQCTL_CBU_FRCHIGH	BIT(9)
 54#define AQCTL_CBU_FRCTOGGLE	(BIT(9) | BIT(8))
 55#define AQCTL_CAU_MASK		(BIT(5) | BIT(4))
 56#define AQCTL_CAU_FRCLOW	BIT(4)
 57#define AQCTL_CAU_FRCHIGH	BIT(5)
 58#define AQCTL_CAU_FRCTOGGLE	(BIT(5) | BIT(4))
 59#define AQCTL_PRD_MASK		(BIT(3) | BIT(2))
 60#define AQCTL_PRD_FRCLOW	BIT(2)
 61#define AQCTL_PRD_FRCHIGH	BIT(3)
 62#define AQCTL_PRD_FRCTOGGLE	(BIT(3) | BIT(2))
 63#define AQCTL_ZRO_MASK		(BIT(1) | BIT(0))
 64#define AQCTL_ZRO_FRCLOW	BIT(0)
 65#define AQCTL_ZRO_FRCHIGH	BIT(1)
 66#define AQCTL_ZRO_FRCTOGGLE	(BIT(1) | BIT(0))
 67
 68#define AQCTL_CHANA_POLNORMAL	(AQCTL_CAU_FRCLOW | AQCTL_PRD_FRCHIGH | \
 69				AQCTL_ZRO_FRCHIGH)
 70#define AQCTL_CHANA_POLINVERSED	(AQCTL_CAU_FRCHIGH | AQCTL_PRD_FRCLOW | \
 71				AQCTL_ZRO_FRCLOW)
 72#define AQCTL_CHANB_POLNORMAL	(AQCTL_CBU_FRCLOW | AQCTL_PRD_FRCHIGH | \
 73				AQCTL_ZRO_FRCHIGH)
 74#define AQCTL_CHANB_POLINVERSED	(AQCTL_CBU_FRCHIGH | AQCTL_PRD_FRCLOW | \
 75				AQCTL_ZRO_FRCLOW)
 76
 77#define AQSFRC_RLDCSF_MASK	(BIT(7) | BIT(6))
 78#define AQSFRC_RLDCSF_ZRO	0
 79#define AQSFRC_RLDCSF_PRD	BIT(6)
 80#define AQSFRC_RLDCSF_ZROPRD	BIT(7)
 81#define AQSFRC_RLDCSF_IMDT	(BIT(7) | BIT(6))
 82
 83#define AQCSFRC_CSFB_MASK	(BIT(3) | BIT(2))
 84#define AQCSFRC_CSFB_FRCDIS	0
 85#define AQCSFRC_CSFB_FRCLOW	BIT(2)
 86#define AQCSFRC_CSFB_FRCHIGH	BIT(3)
 87#define AQCSFRC_CSFB_DISSWFRC	(BIT(3) | BIT(2))
 88#define AQCSFRC_CSFA_MASK	(BIT(1) | BIT(0))
 89#define AQCSFRC_CSFA_FRCDIS	0
 90#define AQCSFRC_CSFA_FRCLOW	BIT(0)
 91#define AQCSFRC_CSFA_FRCHIGH	BIT(1)
 92#define AQCSFRC_CSFA_DISSWFRC	(BIT(1) | BIT(0))
 93
 94#define NUM_PWM_CHANNEL		2	/* EHRPWM channels */
 95
 96struct ehrpwm_context {
 97	u16 tbctl;
 98	u16 tbprd;
 99	u16 cmpa;
100	u16 cmpb;
101	u16 aqctla;
102	u16 aqctlb;
103	u16 aqsfrc;
104	u16 aqcsfrc;
105};
106
107struct ehrpwm_pwm_chip {
108	struct pwm_chip chip;
109	unsigned long clk_rate;
110	void __iomem *mmio_base;
111	unsigned long period_cycles[NUM_PWM_CHANNEL];
112	enum pwm_polarity polarity[NUM_PWM_CHANNEL];
113	struct clk *tbclk;
114	struct ehrpwm_context ctx;
115};
116
117static inline struct ehrpwm_pwm_chip *to_ehrpwm_pwm_chip(struct pwm_chip *chip)
118{
119	return container_of(chip, struct ehrpwm_pwm_chip, chip);
120}
121
122static inline u16 ehrpwm_read(void __iomem *base, unsigned int offset)
123{
124	return readw(base + offset);
125}
126
127static inline void ehrpwm_write(void __iomem *base, unsigned int offset,
128				u16 value)
129{
130	writew(value, base + offset);
131}
132
133static void ehrpwm_modify(void __iomem *base, unsigned int offset, u16 mask,
134			  u16 value)
135{
136	unsigned short val;
137
138	val = readw(base + offset);
139	val &= ~mask;
140	val |= value & mask;
141	writew(val, base + offset);
142}
143
144/**
145 * set_prescale_div -	Set up the prescaler divider function
146 * @rqst_prescaler:	prescaler value min
147 * @prescale_div:	prescaler value set
148 * @tb_clk_div:		Time Base Control prescaler bits
149 */
150static int set_prescale_div(unsigned long rqst_prescaler, u16 *prescale_div,
151			    u16 *tb_clk_div)
152{
153	unsigned int clkdiv, hspclkdiv;
154
155	for (clkdiv = 0; clkdiv <= CLKDIV_MAX; clkdiv++) {
156		for (hspclkdiv = 0; hspclkdiv <= HSPCLKDIV_MAX; hspclkdiv++) {
157			/*
158			 * calculations for prescaler value :
159			 * prescale_div = HSPCLKDIVIDER * CLKDIVIDER.
160			 * HSPCLKDIVIDER =  2 ** hspclkdiv
161			 * CLKDIVIDER = (1),		if clkdiv == 0 *OR*
162			 *		(2 * clkdiv),	if clkdiv != 0
163			 *
164			 * Configure prescale_div value such that period
165			 * register value is less than 65535.
166			 */
167
168			*prescale_div = (1 << clkdiv) *
169					(hspclkdiv ? (hspclkdiv * 2) : 1);
170			if (*prescale_div > rqst_prescaler) {
171				*tb_clk_div = (clkdiv << TBCTL_CLKDIV_SHIFT) |
172					(hspclkdiv << TBCTL_HSPCLKDIV_SHIFT);
173				return 0;
174			}
175		}
176	}
177
178	return 1;
179}
180
181static void configure_polarity(struct ehrpwm_pwm_chip *pc, int chan)
182{
183	u16 aqctl_val, aqctl_mask;
184	unsigned int aqctl_reg;
185
186	/*
187	 * Configure PWM output to HIGH/LOW level on counter
188	 * reaches compare register value and LOW/HIGH level
189	 * on counter value reaches period register value and
190	 * zero value on counter
191	 */
192	if (chan == 1) {
193		aqctl_reg = AQCTLB;
194		aqctl_mask = AQCTL_CBU_MASK;
195
196		if (pc->polarity[chan] == PWM_POLARITY_INVERSED)
197			aqctl_val = AQCTL_CHANB_POLINVERSED;
198		else
199			aqctl_val = AQCTL_CHANB_POLNORMAL;
200	} else {
201		aqctl_reg = AQCTLA;
202		aqctl_mask = AQCTL_CAU_MASK;
203
204		if (pc->polarity[chan] == PWM_POLARITY_INVERSED)
205			aqctl_val = AQCTL_CHANA_POLINVERSED;
206		else
207			aqctl_val = AQCTL_CHANA_POLNORMAL;
208	}
209
210	aqctl_mask |= AQCTL_PRD_MASK | AQCTL_ZRO_MASK;
211	ehrpwm_modify(pc->mmio_base, aqctl_reg, aqctl_mask, aqctl_val);
212}
213
214/*
215 * period_ns = 10^9 * (ps_divval * period_cycles) / PWM_CLK_RATE
216 * duty_ns   = 10^9 * (ps_divval * duty_cycles) / PWM_CLK_RATE
217 */
218static int ehrpwm_pwm_config(struct pwm_chip *chip, struct pwm_device *pwm,
219			     u64 duty_ns, u64 period_ns)
220{
221	struct ehrpwm_pwm_chip *pc = to_ehrpwm_pwm_chip(chip);
222	u32 period_cycles, duty_cycles;
223	u16 ps_divval, tb_divval;
224	unsigned int i, cmp_reg;
225	unsigned long long c;
226
227	if (period_ns > NSEC_PER_SEC)
228		return -ERANGE;
229
230	c = pc->clk_rate;
231	c = c * period_ns;
232	do_div(c, NSEC_PER_SEC);
233	period_cycles = (unsigned long)c;
234
235	if (period_cycles < 1) {
236		period_cycles = 1;
237		duty_cycles = 1;
238	} else {
239		c = pc->clk_rate;
240		c = c * duty_ns;
241		do_div(c, NSEC_PER_SEC);
242		duty_cycles = (unsigned long)c;
243	}
244
245	/*
246	 * Period values should be same for multiple PWM channels as IP uses
247	 * same period register for multiple channels.
248	 */
249	for (i = 0; i < NUM_PWM_CHANNEL; i++) {
250		if (pc->period_cycles[i] &&
251				(pc->period_cycles[i] != period_cycles)) {
252			/*
253			 * Allow channel to reconfigure period if no other
254			 * channels being configured.
255			 */
256			if (i == pwm->hwpwm)
257				continue;
258
259			dev_err(chip->dev,
260				"period value conflicts with channel %u\n",
261				i);
262			return -EINVAL;
263		}
264	}
265
266	pc->period_cycles[pwm->hwpwm] = period_cycles;
267
268	/* Configure clock prescaler to support Low frequency PWM wave */
269	if (set_prescale_div(period_cycles/PERIOD_MAX, &ps_divval,
270			     &tb_divval)) {
271		dev_err(chip->dev, "Unsupported values\n");
272		return -EINVAL;
273	}
274
275	pm_runtime_get_sync(chip->dev);
276
277	/* Update clock prescaler values */
278	ehrpwm_modify(pc->mmio_base, TBCTL, TBCTL_CLKDIV_MASK, tb_divval);
279
280	/* Update period & duty cycle with presacler division */
281	period_cycles = period_cycles / ps_divval;
282	duty_cycles = duty_cycles / ps_divval;
283
284	/* Configure shadow loading on Period register */
285	ehrpwm_modify(pc->mmio_base, TBCTL, TBCTL_PRDLD_MASK, TBCTL_PRDLD_SHDW);
286
287	ehrpwm_write(pc->mmio_base, TBPRD, period_cycles);
288
289	/* Configure ehrpwm counter for up-count mode */
290	ehrpwm_modify(pc->mmio_base, TBCTL, TBCTL_CTRMODE_MASK,
291		      TBCTL_CTRMODE_UP);
292
293	if (pwm->hwpwm == 1)
294		/* Channel 1 configured with compare B register */
295		cmp_reg = CMPB;
296	else
297		/* Channel 0 configured with compare A register */
298		cmp_reg = CMPA;
299
300	ehrpwm_write(pc->mmio_base, cmp_reg, duty_cycles);
301
302	pm_runtime_put_sync(chip->dev);
303
304	return 0;
305}
306
307static int ehrpwm_pwm_set_polarity(struct pwm_chip *chip,
308				   struct pwm_device *pwm,
309				   enum pwm_polarity polarity)
310{
311	struct ehrpwm_pwm_chip *pc = to_ehrpwm_pwm_chip(chip);
312
313	/* Configuration of polarity in hardware delayed, do at enable */
314	pc->polarity[pwm->hwpwm] = polarity;
315
316	return 0;
317}
318
319static int ehrpwm_pwm_enable(struct pwm_chip *chip, struct pwm_device *pwm)
320{
321	struct ehrpwm_pwm_chip *pc = to_ehrpwm_pwm_chip(chip);
322	u16 aqcsfrc_val, aqcsfrc_mask;
323	int ret;
324
325	/* Leave clock enabled on enabling PWM */
326	pm_runtime_get_sync(chip->dev);
327
328	/* Disabling Action Qualifier on PWM output */
329	if (pwm->hwpwm) {
330		aqcsfrc_val = AQCSFRC_CSFB_FRCDIS;
331		aqcsfrc_mask = AQCSFRC_CSFB_MASK;
332	} else {
333		aqcsfrc_val = AQCSFRC_CSFA_FRCDIS;
334		aqcsfrc_mask = AQCSFRC_CSFA_MASK;
335	}
336
337	/* Changes to shadow mode */
338	ehrpwm_modify(pc->mmio_base, AQSFRC, AQSFRC_RLDCSF_MASK,
339		      AQSFRC_RLDCSF_ZRO);
340
341	ehrpwm_modify(pc->mmio_base, AQCSFRC, aqcsfrc_mask, aqcsfrc_val);
342
343	/* Channels polarity can be configured from action qualifier module */
344	configure_polarity(pc, pwm->hwpwm);
345
346	/* Enable TBCLK */
347	ret = clk_enable(pc->tbclk);
348	if (ret) {
349		dev_err(chip->dev, "Failed to enable TBCLK for %s: %d\n",
350			dev_name(pc->chip.dev), ret);
351		return ret;
352	}
353
 
 
 
354	return 0;
355}
356
357static void ehrpwm_pwm_disable(struct pwm_chip *chip, struct pwm_device *pwm)
358{
359	struct ehrpwm_pwm_chip *pc = to_ehrpwm_pwm_chip(chip);
360	u16 aqcsfrc_val, aqcsfrc_mask;
361
362	/* Action Qualifier puts PWM output low forcefully */
363	if (pwm->hwpwm) {
364		aqcsfrc_val = AQCSFRC_CSFB_FRCLOW;
365		aqcsfrc_mask = AQCSFRC_CSFB_MASK;
366	} else {
367		aqcsfrc_val = AQCSFRC_CSFA_FRCLOW;
368		aqcsfrc_mask = AQCSFRC_CSFA_MASK;
369	}
370
371	/* Update shadow register first before modifying active register */
372	ehrpwm_modify(pc->mmio_base, AQSFRC, AQSFRC_RLDCSF_MASK,
373		      AQSFRC_RLDCSF_ZRO);
374	ehrpwm_modify(pc->mmio_base, AQCSFRC, aqcsfrc_mask, aqcsfrc_val);
375	/*
376	 * Changes to immediate action on Action Qualifier. This puts
377	 * Action Qualifier control on PWM output from next TBCLK
378	 */
379	ehrpwm_modify(pc->mmio_base, AQSFRC, AQSFRC_RLDCSF_MASK,
380		      AQSFRC_RLDCSF_IMDT);
381
382	ehrpwm_modify(pc->mmio_base, AQCSFRC, aqcsfrc_mask, aqcsfrc_val);
383
384	/* Disabling TBCLK on PWM disable */
385	clk_disable(pc->tbclk);
386
 
 
 
387	/* Disable clock on PWM disable */
388	pm_runtime_put_sync(chip->dev);
389}
390
391static void ehrpwm_pwm_free(struct pwm_chip *chip, struct pwm_device *pwm)
392{
393	struct ehrpwm_pwm_chip *pc = to_ehrpwm_pwm_chip(chip);
394
395	if (pwm_is_enabled(pwm)) {
396		dev_warn(chip->dev, "Removing PWM device without disabling\n");
397		pm_runtime_put_sync(chip->dev);
398	}
399
400	/* set period value to zero on free */
401	pc->period_cycles[pwm->hwpwm] = 0;
402}
403
404static int ehrpwm_pwm_apply(struct pwm_chip *chip, struct pwm_device *pwm,
405			    const struct pwm_state *state)
406{
407	int err;
408	bool enabled = pwm->state.enabled;
409
410	if (state->polarity != pwm->state.polarity) {
411		if (enabled) {
412			ehrpwm_pwm_disable(chip, pwm);
413			enabled = false;
414		}
415
416		err = ehrpwm_pwm_set_polarity(chip, pwm, state->polarity);
417		if (err)
418			return err;
419	}
420
421	if (!state->enabled) {
422		if (enabled)
423			ehrpwm_pwm_disable(chip, pwm);
424		return 0;
425	}
426
427	err = ehrpwm_pwm_config(chip, pwm, state->duty_cycle, state->period);
428	if (err)
429		return err;
430
431	if (!enabled)
432		err = ehrpwm_pwm_enable(chip, pwm);
433
434	return err;
435}
436
437static const struct pwm_ops ehrpwm_pwm_ops = {
438	.free = ehrpwm_pwm_free,
439	.apply = ehrpwm_pwm_apply,
 
 
 
 
440};
441
442static const struct of_device_id ehrpwm_of_match[] = {
443	{ .compatible = "ti,am3352-ehrpwm" },
444	{ .compatible = "ti,am33xx-ehrpwm" },
445	{},
446};
447MODULE_DEVICE_TABLE(of, ehrpwm_of_match);
448
449static int ehrpwm_pwm_probe(struct platform_device *pdev)
450{
451	struct device_node *np = pdev->dev.of_node;
452	struct ehrpwm_pwm_chip *pc;
 
453	struct clk *clk;
454	int ret;
455
456	pc = devm_kzalloc(&pdev->dev, sizeof(*pc), GFP_KERNEL);
457	if (!pc)
458		return -ENOMEM;
459
460	clk = devm_clk_get(&pdev->dev, "fck");
461	if (IS_ERR(clk)) {
462		if (of_device_is_compatible(np, "ti,am33xx-ecap")) {
463			dev_warn(&pdev->dev, "Binding is obsolete.\n");
464			clk = devm_clk_get(pdev->dev.parent, "fck");
465		}
466	}
467
468	if (IS_ERR(clk))
469		return dev_err_probe(&pdev->dev, PTR_ERR(clk), "Failed to get fck\n");
 
 
470
471	pc->clk_rate = clk_get_rate(clk);
472	if (!pc->clk_rate) {
473		dev_err(&pdev->dev, "failed to get clock rate\n");
474		return -EINVAL;
475	}
476
477	pc->chip.dev = &pdev->dev;
478	pc->chip.ops = &ehrpwm_pwm_ops;
 
 
 
479	pc->chip.npwm = NUM_PWM_CHANNEL;
480
481	pc->mmio_base = devm_platform_ioremap_resource(pdev, 0);
 
482	if (IS_ERR(pc->mmio_base))
483		return PTR_ERR(pc->mmio_base);
484
485	/* Acquire tbclk for Time Base EHRPWM submodule */
486	pc->tbclk = devm_clk_get(&pdev->dev, "tbclk");
487	if (IS_ERR(pc->tbclk))
488		return dev_err_probe(&pdev->dev, PTR_ERR(pc->tbclk), "Failed to get tbclk\n");
 
 
489
490	ret = clk_prepare(pc->tbclk);
491	if (ret < 0) {
492		dev_err(&pdev->dev, "clk_prepare() failed: %d\n", ret);
493		return ret;
494	}
495
496	ret = pwmchip_add(&pc->chip);
497	if (ret < 0) {
498		dev_err(&pdev->dev, "pwmchip_add() failed: %d\n", ret);
499		goto err_clk_unprepare;
500	}
501
502	platform_set_drvdata(pdev, pc);
503	pm_runtime_enable(&pdev->dev);
504
505	return 0;
506
507err_clk_unprepare:
508	clk_unprepare(pc->tbclk);
509
510	return ret;
511}
512
513static void ehrpwm_pwm_remove(struct platform_device *pdev)
514{
515	struct ehrpwm_pwm_chip *pc = platform_get_drvdata(pdev);
516
517	pwmchip_remove(&pc->chip);
518
519	clk_unprepare(pc->tbclk);
520
521	pm_runtime_disable(&pdev->dev);
 
 
522}
523
 
524static void ehrpwm_pwm_save_context(struct ehrpwm_pwm_chip *pc)
525{
526	pm_runtime_get_sync(pc->chip.dev);
527
528	pc->ctx.tbctl = ehrpwm_read(pc->mmio_base, TBCTL);
529	pc->ctx.tbprd = ehrpwm_read(pc->mmio_base, TBPRD);
530	pc->ctx.cmpa = ehrpwm_read(pc->mmio_base, CMPA);
531	pc->ctx.cmpb = ehrpwm_read(pc->mmio_base, CMPB);
532	pc->ctx.aqctla = ehrpwm_read(pc->mmio_base, AQCTLA);
533	pc->ctx.aqctlb = ehrpwm_read(pc->mmio_base, AQCTLB);
534	pc->ctx.aqsfrc = ehrpwm_read(pc->mmio_base, AQSFRC);
535	pc->ctx.aqcsfrc = ehrpwm_read(pc->mmio_base, AQCSFRC);
536
537	pm_runtime_put_sync(pc->chip.dev);
538}
539
540static void ehrpwm_pwm_restore_context(struct ehrpwm_pwm_chip *pc)
541{
542	ehrpwm_write(pc->mmio_base, TBPRD, pc->ctx.tbprd);
543	ehrpwm_write(pc->mmio_base, CMPA, pc->ctx.cmpa);
544	ehrpwm_write(pc->mmio_base, CMPB, pc->ctx.cmpb);
545	ehrpwm_write(pc->mmio_base, AQCTLA, pc->ctx.aqctla);
546	ehrpwm_write(pc->mmio_base, AQCTLB, pc->ctx.aqctlb);
547	ehrpwm_write(pc->mmio_base, AQSFRC, pc->ctx.aqsfrc);
548	ehrpwm_write(pc->mmio_base, AQCSFRC, pc->ctx.aqcsfrc);
549	ehrpwm_write(pc->mmio_base, TBCTL, pc->ctx.tbctl);
550}
551
552static int ehrpwm_pwm_suspend(struct device *dev)
553{
554	struct ehrpwm_pwm_chip *pc = dev_get_drvdata(dev);
555	unsigned int i;
556
557	ehrpwm_pwm_save_context(pc);
558
559	for (i = 0; i < pc->chip.npwm; i++) {
560		struct pwm_device *pwm = &pc->chip.pwms[i];
561
562		if (!pwm_is_enabled(pwm))
563			continue;
564
565		/* Disable explicitly if PWM is running */
566		pm_runtime_put_sync(dev);
567	}
568
569	return 0;
570}
571
572static int ehrpwm_pwm_resume(struct device *dev)
573{
574	struct ehrpwm_pwm_chip *pc = dev_get_drvdata(dev);
575	unsigned int i;
576
577	for (i = 0; i < pc->chip.npwm; i++) {
578		struct pwm_device *pwm = &pc->chip.pwms[i];
579
580		if (!pwm_is_enabled(pwm))
581			continue;
582
583		/* Enable explicitly if PWM was running */
584		pm_runtime_get_sync(dev);
585	}
586
587	ehrpwm_pwm_restore_context(pc);
588
589	return 0;
590}
 
591
592static DEFINE_SIMPLE_DEV_PM_OPS(ehrpwm_pwm_pm_ops, ehrpwm_pwm_suspend,
593				ehrpwm_pwm_resume);
594
595static struct platform_driver ehrpwm_pwm_driver = {
596	.driver = {
597		.name = "ehrpwm",
598		.of_match_table = ehrpwm_of_match,
599		.pm = pm_ptr(&ehrpwm_pwm_pm_ops),
600	},
601	.probe = ehrpwm_pwm_probe,
602	.remove_new = ehrpwm_pwm_remove,
603};
604module_platform_driver(ehrpwm_pwm_driver);
605
606MODULE_DESCRIPTION("EHRPWM PWM driver");
607MODULE_AUTHOR("Texas Instruments");
608MODULE_LICENSE("GPL");