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v4.6
 
  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#include "pwm-tipwmss.h"
 31
 32/* EHRPWM registers and bits definitions */
 33
 34/* Time base module registers */
 35#define TBCTL			0x00
 36#define TBPRD			0x0A
 37
 38#define TBCTL_RUN_MASK		(BIT(15) | BIT(14))
 39#define TBCTL_STOP_NEXT		0
 40#define TBCTL_STOP_ON_CYCLE	BIT(14)
 41#define TBCTL_FREE_RUN		(BIT(15) | BIT(14))
 42#define TBCTL_PRDLD_MASK	BIT(3)
 43#define TBCTL_PRDLD_SHDW	0
 44#define TBCTL_PRDLD_IMDT	BIT(3)
 45#define TBCTL_CLKDIV_MASK	(BIT(12) | BIT(11) | BIT(10) | BIT(9) | \
 46				BIT(8) | BIT(7))
 47#define TBCTL_CTRMODE_MASK	(BIT(1) | BIT(0))
 48#define TBCTL_CTRMODE_UP	0
 49#define TBCTL_CTRMODE_DOWN	BIT(0)
 50#define TBCTL_CTRMODE_UPDOWN	BIT(1)
 51#define TBCTL_CTRMODE_FREEZE	(BIT(1) | BIT(0))
 52
 53#define TBCTL_HSPCLKDIV_SHIFT	7
 54#define TBCTL_CLKDIV_SHIFT	10
 55
 56#define CLKDIV_MAX		7
 57#define HSPCLKDIV_MAX		7
 58#define PERIOD_MAX		0xFFFF
 59
 60/* compare module registers */
 61#define CMPA			0x12
 62#define CMPB			0x14
 63
 64/* Action qualifier module registers */
 65#define AQCTLA			0x16
 66#define AQCTLB			0x18
 67#define AQSFRC			0x1A
 68#define AQCSFRC			0x1C
 69
 70#define AQCTL_CBU_MASK		(BIT(9) | BIT(8))
 71#define AQCTL_CBU_FRCLOW	BIT(8)
 72#define AQCTL_CBU_FRCHIGH	BIT(9)
 73#define AQCTL_CBU_FRCTOGGLE	(BIT(9) | BIT(8))
 74#define AQCTL_CAU_MASK		(BIT(5) | BIT(4))
 75#define AQCTL_CAU_FRCLOW	BIT(4)
 76#define AQCTL_CAU_FRCHIGH	BIT(5)
 77#define AQCTL_CAU_FRCTOGGLE	(BIT(5) | BIT(4))
 78#define AQCTL_PRD_MASK		(BIT(3) | BIT(2))
 79#define AQCTL_PRD_FRCLOW	BIT(2)
 80#define AQCTL_PRD_FRCHIGH	BIT(3)
 81#define AQCTL_PRD_FRCTOGGLE	(BIT(3) | BIT(2))
 82#define AQCTL_ZRO_MASK		(BIT(1) | BIT(0))
 83#define AQCTL_ZRO_FRCLOW	BIT(0)
 84#define AQCTL_ZRO_FRCHIGH	BIT(1)
 85#define AQCTL_ZRO_FRCTOGGLE	(BIT(1) | BIT(0))
 86
 87#define AQCTL_CHANA_POLNORMAL	(AQCTL_CAU_FRCLOW | AQCTL_PRD_FRCHIGH | \
 88				AQCTL_ZRO_FRCHIGH)
 89#define AQCTL_CHANA_POLINVERSED	(AQCTL_CAU_FRCHIGH | AQCTL_PRD_FRCLOW | \
 90				AQCTL_ZRO_FRCLOW)
 91#define AQCTL_CHANB_POLNORMAL	(AQCTL_CBU_FRCLOW | AQCTL_PRD_FRCHIGH | \
 92				AQCTL_ZRO_FRCHIGH)
 93#define AQCTL_CHANB_POLINVERSED	(AQCTL_CBU_FRCHIGH | AQCTL_PRD_FRCLOW | \
 94				AQCTL_ZRO_FRCLOW)
 95
 96#define AQSFRC_RLDCSF_MASK	(BIT(7) | BIT(6))
 97#define AQSFRC_RLDCSF_ZRO	0
 98#define AQSFRC_RLDCSF_PRD	BIT(6)
 99#define AQSFRC_RLDCSF_ZROPRD	BIT(7)
100#define AQSFRC_RLDCSF_IMDT	(BIT(7) | BIT(6))
101
102#define AQCSFRC_CSFB_MASK	(BIT(3) | BIT(2))
103#define AQCSFRC_CSFB_FRCDIS	0
104#define AQCSFRC_CSFB_FRCLOW	BIT(2)
105#define AQCSFRC_CSFB_FRCHIGH	BIT(3)
106#define AQCSFRC_CSFB_DISSWFRC	(BIT(3) | BIT(2))
107#define AQCSFRC_CSFA_MASK	(BIT(1) | BIT(0))
108#define AQCSFRC_CSFA_FRCDIS	0
109#define AQCSFRC_CSFA_FRCLOW	BIT(0)
110#define AQCSFRC_CSFA_FRCHIGH	BIT(1)
111#define AQCSFRC_CSFA_DISSWFRC	(BIT(1) | BIT(0))
112
113#define NUM_PWM_CHANNEL		2	/* EHRPWM channels */
114
115struct ehrpwm_context {
116	u16 tbctl;
117	u16 tbprd;
118	u16 cmpa;
119	u16 cmpb;
120	u16 aqctla;
121	u16 aqctlb;
122	u16 aqsfrc;
123	u16 aqcsfrc;
124};
125
126struct ehrpwm_pwm_chip {
127	struct pwm_chip	chip;
128	unsigned int	clk_rate;
129	void __iomem	*mmio_base;
130	unsigned long period_cycles[NUM_PWM_CHANNEL];
131	enum pwm_polarity polarity[NUM_PWM_CHANNEL];
132	struct	clk	*tbclk;
133	struct ehrpwm_context ctx;
134};
135
136static inline struct ehrpwm_pwm_chip *to_ehrpwm_pwm_chip(struct pwm_chip *chip)
137{
138	return container_of(chip, struct ehrpwm_pwm_chip, chip);
139}
140
141static inline u16 ehrpwm_read(void __iomem *base, int offset)
142{
143	return readw(base + offset);
144}
145
146static inline void ehrpwm_write(void __iomem *base, int offset, unsigned int val)
 
147{
148	writew(val & 0xFFFF, base + offset);
149}
150
151static void ehrpwm_modify(void __iomem *base, int offset,
152		unsigned short mask, unsigned short val)
153{
154	unsigned short regval;
155
156	regval = readw(base + offset);
157	regval &= ~mask;
158	regval |= val & mask;
159	writew(regval, base + offset);
160}
161
162/**
163 * set_prescale_div -	Set up the prescaler divider function
164 * @rqst_prescaler:	prescaler value min
165 * @prescale_div:	prescaler value set
166 * @tb_clk_div:		Time Base Control prescaler bits
167 */
168static int set_prescale_div(unsigned long rqst_prescaler,
169		unsigned short *prescale_div, unsigned short *tb_clk_div)
170{
171	unsigned int clkdiv, hspclkdiv;
172
173	for (clkdiv = 0; clkdiv <= CLKDIV_MAX; clkdiv++) {
174		for (hspclkdiv = 0; hspclkdiv <= HSPCLKDIV_MAX; hspclkdiv++) {
175
176			/*
177			 * calculations for prescaler value :
178			 * prescale_div = HSPCLKDIVIDER * CLKDIVIDER.
179			 * HSPCLKDIVIDER =  2 ** hspclkdiv
180			 * CLKDIVIDER = (1),		if clkdiv == 0 *OR*
181			 *		(2 * clkdiv),	if clkdiv != 0
182			 *
183			 * Configure prescale_div value such that period
184			 * register value is less than 65535.
185			 */
186
187			*prescale_div = (1 << clkdiv) *
188					(hspclkdiv ? (hspclkdiv * 2) : 1);
189			if (*prescale_div > rqst_prescaler) {
190				*tb_clk_div = (clkdiv << TBCTL_CLKDIV_SHIFT) |
191					(hspclkdiv << TBCTL_HSPCLKDIV_SHIFT);
192				return 0;
193			}
194		}
195	}
 
196	return 1;
197}
198
199static void configure_polarity(struct ehrpwm_pwm_chip *pc, int chan)
200{
201	int aqctl_reg;
202	unsigned short aqctl_val, aqctl_mask;
203
204	/*
205	 * Configure PWM output to HIGH/LOW level on counter
206	 * reaches compare register value and LOW/HIGH level
207	 * on counter value reaches period register value and
208	 * zero value on counter
209	 */
210	if (chan == 1) {
211		aqctl_reg = AQCTLB;
212		aqctl_mask = AQCTL_CBU_MASK;
213
214		if (pc->polarity[chan] == PWM_POLARITY_INVERSED)
215			aqctl_val = AQCTL_CHANB_POLINVERSED;
216		else
217			aqctl_val = AQCTL_CHANB_POLNORMAL;
218	} else {
219		aqctl_reg = AQCTLA;
220		aqctl_mask = AQCTL_CAU_MASK;
221
222		if (pc->polarity[chan] == PWM_POLARITY_INVERSED)
223			aqctl_val = AQCTL_CHANA_POLINVERSED;
224		else
225			aqctl_val = AQCTL_CHANA_POLNORMAL;
226	}
227
228	aqctl_mask |= AQCTL_PRD_MASK | AQCTL_ZRO_MASK;
229	ehrpwm_modify(pc->mmio_base, aqctl_reg, aqctl_mask, aqctl_val);
230}
231
232/*
233 * period_ns = 10^9 * (ps_divval * period_cycles) / PWM_CLK_RATE
234 * duty_ns   = 10^9 * (ps_divval * duty_cycles) / PWM_CLK_RATE
235 */
236static int ehrpwm_pwm_config(struct pwm_chip *chip, struct pwm_device *pwm,
237		int duty_ns, int period_ns)
238{
239	struct ehrpwm_pwm_chip *pc = to_ehrpwm_pwm_chip(chip);
 
 
 
240	unsigned long long c;
241	unsigned long period_cycles, duty_cycles;
242	unsigned short ps_divval, tb_divval;
243	int i, cmp_reg;
244
245	if (period_ns > NSEC_PER_SEC)
246		return -ERANGE;
247
248	c = pc->clk_rate;
249	c = c * period_ns;
250	do_div(c, NSEC_PER_SEC);
251	period_cycles = (unsigned long)c;
252
253	if (period_cycles < 1) {
254		period_cycles = 1;
255		duty_cycles = 1;
256	} else {
257		c = pc->clk_rate;
258		c = c * duty_ns;
259		do_div(c, NSEC_PER_SEC);
260		duty_cycles = (unsigned long)c;
261	}
262
263	/*
264	 * Period values should be same for multiple PWM channels as IP uses
265	 * same period register for multiple channels.
266	 */
267	for (i = 0; i < NUM_PWM_CHANNEL; i++) {
268		if (pc->period_cycles[i] &&
269				(pc->period_cycles[i] != period_cycles)) {
270			/*
271			 * Allow channel to reconfigure period if no other
272			 * channels being configured.
273			 */
274			if (i == pwm->hwpwm)
275				continue;
276
277			dev_err(chip->dev, "Period value conflicts with channel %d\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	return 0;
321}
322
323static int ehrpwm_pwm_set_polarity(struct pwm_chip *chip,
324		struct pwm_device *pwm,	enum pwm_polarity polarity)
 
325{
326	struct ehrpwm_pwm_chip *pc = to_ehrpwm_pwm_chip(chip);
327
328	/* Configuration of polarity in hardware delayed, do at enable */
329	pc->polarity[pwm->hwpwm] = polarity;
 
330	return 0;
331}
332
333static int ehrpwm_pwm_enable(struct pwm_chip *chip, struct pwm_device *pwm)
334{
335	struct ehrpwm_pwm_chip *pc = to_ehrpwm_pwm_chip(chip);
336	unsigned short aqcsfrc_val, aqcsfrc_mask;
337	int ret;
338
339	/* Leave clock enabled on enabling PWM */
340	pm_runtime_get_sync(chip->dev);
341
342	/* Disabling Action Qualifier on PWM output */
343	if (pwm->hwpwm) {
344		aqcsfrc_val = AQCSFRC_CSFB_FRCDIS;
345		aqcsfrc_mask = AQCSFRC_CSFB_MASK;
346	} else {
347		aqcsfrc_val = AQCSFRC_CSFA_FRCDIS;
348		aqcsfrc_mask = AQCSFRC_CSFA_MASK;
349	}
350
351	/* Changes to shadow mode */
352	ehrpwm_modify(pc->mmio_base, AQSFRC, AQSFRC_RLDCSF_MASK,
353			AQSFRC_RLDCSF_ZRO);
354
355	ehrpwm_modify(pc->mmio_base, AQCSFRC, aqcsfrc_mask, aqcsfrc_val);
356
357	/* Channels polarity can be configured from action qualifier module */
358	configure_polarity(pc, pwm->hwpwm);
359
360	/* Enable TBCLK before enabling PWM device */
361	ret = clk_enable(pc->tbclk);
362	if (ret) {
363		dev_err(chip->dev, "Failed to enable TBCLK for %s\n",
364			dev_name(pc->chip.dev));
365		return ret;
366	}
367
368	/* Enable time counter for free_run */
369	ehrpwm_modify(pc->mmio_base, TBCTL, TBCTL_RUN_MASK, TBCTL_FREE_RUN);
370	return 0;
371}
372
373static void ehrpwm_pwm_disable(struct pwm_chip *chip, struct pwm_device *pwm)
374{
375	struct ehrpwm_pwm_chip *pc = to_ehrpwm_pwm_chip(chip);
376	unsigned short aqcsfrc_val, aqcsfrc_mask;
377
378	/* Action Qualifier puts PWM output low forcefully */
379	if (pwm->hwpwm) {
380		aqcsfrc_val = AQCSFRC_CSFB_FRCLOW;
381		aqcsfrc_mask = AQCSFRC_CSFB_MASK;
382	} else {
383		aqcsfrc_val = AQCSFRC_CSFA_FRCLOW;
384		aqcsfrc_mask = AQCSFRC_CSFA_MASK;
385	}
386
 
 
 
 
387	/*
388	 * Changes to immediate action on Action Qualifier. This puts
389	 * Action Qualifier control on PWM output from next TBCLK
390	 */
391	ehrpwm_modify(pc->mmio_base, AQSFRC, AQSFRC_RLDCSF_MASK,
392			AQSFRC_RLDCSF_IMDT);
393
394	ehrpwm_modify(pc->mmio_base, AQCSFRC, aqcsfrc_mask, aqcsfrc_val);
395
396	/* Disabling TBCLK on PWM disable */
397	clk_disable(pc->tbclk);
398
399	/* Stop Time base counter */
400	ehrpwm_modify(pc->mmio_base, TBCTL, TBCTL_RUN_MASK, TBCTL_STOP_NEXT);
401
402	/* Disable clock on PWM disable */
403	pm_runtime_put_sync(chip->dev);
404}
405
406static void ehrpwm_pwm_free(struct pwm_chip *chip, struct pwm_device *pwm)
407{
408	struct ehrpwm_pwm_chip *pc = to_ehrpwm_pwm_chip(chip);
409
410	if (pwm_is_enabled(pwm)) {
411		dev_warn(chip->dev, "Removing PWM device without disabling\n");
412		pm_runtime_put_sync(chip->dev);
413	}
414
415	/* set period value to zero on free */
416	pc->period_cycles[pwm->hwpwm] = 0;
417}
418
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
419static const struct pwm_ops ehrpwm_pwm_ops = {
420	.free		= ehrpwm_pwm_free,
421	.config		= ehrpwm_pwm_config,
422	.set_polarity	= ehrpwm_pwm_set_polarity,
423	.enable		= ehrpwm_pwm_enable,
424	.disable	= ehrpwm_pwm_disable,
425	.owner		= THIS_MODULE,
426};
427
428static const struct of_device_id ehrpwm_of_match[] = {
429	{ .compatible	= "ti,am33xx-ehrpwm" },
 
430	{},
431};
432MODULE_DEVICE_TABLE(of, ehrpwm_of_match);
433
434static int ehrpwm_pwm_probe(struct platform_device *pdev)
435{
436	int ret;
437	struct resource *r;
438	struct clk *clk;
439	struct ehrpwm_pwm_chip *pc;
440	u16 status;
 
 
441
442	pc = devm_kzalloc(&pdev->dev, sizeof(*pc), GFP_KERNEL);
443	if (!pc)
444		return -ENOMEM;
 
445
446	clk = devm_clk_get(&pdev->dev, "fck");
447	if (IS_ERR(clk)) {
448		dev_err(&pdev->dev, "failed to get clock\n");
449		return PTR_ERR(clk);
 
 
450	}
451
 
 
 
452	pc->clk_rate = clk_get_rate(clk);
453	if (!pc->clk_rate) {
454		dev_err(&pdev->dev, "failed to get clock rate\n");
455		return -EINVAL;
456	}
457
458	pc->chip.dev = &pdev->dev;
459	pc->chip.ops = &ehrpwm_pwm_ops;
460	pc->chip.of_xlate = of_pwm_xlate_with_flags;
461	pc->chip.of_pwm_n_cells = 3;
462	pc->chip.base = -1;
463	pc->chip.npwm = NUM_PWM_CHANNEL;
464
465	r = platform_get_resource(pdev, IORESOURCE_MEM, 0);
466	pc->mmio_base = devm_ioremap_resource(&pdev->dev, r);
467	if (IS_ERR(pc->mmio_base))
468		return PTR_ERR(pc->mmio_base);
469
470	/* Acquire tbclk for Time Base EHRPWM submodule */
471	pc->tbclk = devm_clk_get(&pdev->dev, "tbclk");
472	if (IS_ERR(pc->tbclk)) {
473		dev_err(&pdev->dev, "Failed to get tbclk\n");
474		return PTR_ERR(pc->tbclk);
475	}
476
477	ret = clk_prepare(pc->tbclk);
478	if (ret < 0) {
479		dev_err(&pdev->dev, "clk_prepare() failed: %d\n", ret);
480		return ret;
481	}
482
483	ret = pwmchip_add(&pc->chip);
484	if (ret < 0) {
485		dev_err(&pdev->dev, "pwmchip_add() failed: %d\n", ret);
486		return ret;
487	}
488
 
489	pm_runtime_enable(&pdev->dev);
490	pm_runtime_get_sync(&pdev->dev);
491
492	status = pwmss_submodule_state_change(pdev->dev.parent,
493			PWMSS_EPWMCLK_EN);
494	if (!(status & PWMSS_EPWMCLK_EN_ACK)) {
495		dev_err(&pdev->dev, "PWMSS config space clock enable failed\n");
496		ret = -EINVAL;
497		goto pwmss_clk_failure;
498	}
499
500	pm_runtime_put_sync(&pdev->dev);
501
502	platform_set_drvdata(pdev, pc);
503	return 0;
504
505pwmss_clk_failure:
506	pm_runtime_put_sync(&pdev->dev);
507	pm_runtime_disable(&pdev->dev);
508	pwmchip_remove(&pc->chip);
509	clk_unprepare(pc->tbclk);
 
510	return ret;
511}
512
513static int ehrpwm_pwm_remove(struct platform_device *pdev)
514{
515	struct ehrpwm_pwm_chip *pc = platform_get_drvdata(pdev);
 
516
517	clk_unprepare(pc->tbclk);
518
519	pm_runtime_get_sync(&pdev->dev);
520	/*
521	 * Due to hardware misbehaviour, acknowledge of the stop_req
522	 * is missing. Hence checking of the status bit skipped.
523	 */
524	pwmss_submodule_state_change(pdev->dev.parent, PWMSS_EPWMCLK_STOP_REQ);
525	pm_runtime_put_sync(&pdev->dev);
526
527	pm_runtime_put_sync(&pdev->dev);
528	pm_runtime_disable(&pdev->dev);
529	return pwmchip_remove(&pc->chip);
530}
531
532#ifdef CONFIG_PM_SLEEP
533static void ehrpwm_pwm_save_context(struct ehrpwm_pwm_chip *pc)
534{
535	pm_runtime_get_sync(pc->chip.dev);
 
 
 
536	pc->ctx.tbctl = ehrpwm_read(pc->mmio_base, TBCTL);
537	pc->ctx.tbprd = ehrpwm_read(pc->mmio_base, TBPRD);
538	pc->ctx.cmpa = ehrpwm_read(pc->mmio_base, CMPA);
539	pc->ctx.cmpb = ehrpwm_read(pc->mmio_base, CMPB);
540	pc->ctx.aqctla = ehrpwm_read(pc->mmio_base, AQCTLA);
541	pc->ctx.aqctlb = ehrpwm_read(pc->mmio_base, AQCTLB);
542	pc->ctx.aqsfrc = ehrpwm_read(pc->mmio_base, AQSFRC);
543	pc->ctx.aqcsfrc = ehrpwm_read(pc->mmio_base, AQCSFRC);
544	pm_runtime_put_sync(pc->chip.dev);
 
545}
546
547static void ehrpwm_pwm_restore_context(struct ehrpwm_pwm_chip *pc)
548{
 
 
549	ehrpwm_write(pc->mmio_base, TBPRD, pc->ctx.tbprd);
550	ehrpwm_write(pc->mmio_base, CMPA, pc->ctx.cmpa);
551	ehrpwm_write(pc->mmio_base, CMPB, pc->ctx.cmpb);
552	ehrpwm_write(pc->mmio_base, AQCTLA, pc->ctx.aqctla);
553	ehrpwm_write(pc->mmio_base, AQCTLB, pc->ctx.aqctlb);
554	ehrpwm_write(pc->mmio_base, AQSFRC, pc->ctx.aqsfrc);
555	ehrpwm_write(pc->mmio_base, AQCSFRC, pc->ctx.aqcsfrc);
556	ehrpwm_write(pc->mmio_base, TBCTL, pc->ctx.tbctl);
557}
558
559static int ehrpwm_pwm_suspend(struct device *dev)
560{
561	struct ehrpwm_pwm_chip *pc = dev_get_drvdata(dev);
562	int i;
 
 
563
564	ehrpwm_pwm_save_context(pc);
565	for (i = 0; i < pc->chip.npwm; i++) {
566		struct pwm_device *pwm = &pc->chip.pwms[i];
567
568		if (!pwm_is_enabled(pwm))
569			continue;
570
571		/* Disable explicitly if PWM is running */
572		pm_runtime_put_sync(dev);
573	}
 
574	return 0;
575}
576
577static int ehrpwm_pwm_resume(struct device *dev)
578{
579	struct ehrpwm_pwm_chip *pc = dev_get_drvdata(dev);
580	int i;
581
582	for (i = 0; i < pc->chip.npwm; i++) {
583		struct pwm_device *pwm = &pc->chip.pwms[i];
584
585		if (!pwm_is_enabled(pwm))
586			continue;
587
588		/* Enable explicitly if PWM was running */
589		pm_runtime_get_sync(dev);
590	}
591	ehrpwm_pwm_restore_context(pc);
 
 
592	return 0;
593}
594#endif
595
596static SIMPLE_DEV_PM_OPS(ehrpwm_pwm_pm_ops, ehrpwm_pwm_suspend,
597		ehrpwm_pwm_resume);
598
599static struct platform_driver ehrpwm_pwm_driver = {
600	.driver = {
601		.name	= "ehrpwm",
602		.of_match_table = ehrpwm_of_match,
603		.pm	= &ehrpwm_pwm_pm_ops,
604	},
605	.probe = ehrpwm_pwm_probe,
606	.remove = ehrpwm_pwm_remove,
607};
608
609module_platform_driver(ehrpwm_pwm_driver);
610
611MODULE_DESCRIPTION("EHRPWM PWM driver");
612MODULE_AUTHOR("Texas Instruments");
613MODULE_LICENSE("GPL");
v6.13.7
  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	unsigned long clk_rate;
109	void __iomem *mmio_base;
 
110	unsigned long period_cycles[NUM_PWM_CHANNEL];
111	enum pwm_polarity polarity[NUM_PWM_CHANNEL];
112	struct clk *tbclk;
113	struct ehrpwm_context ctx;
114};
115
116static inline struct ehrpwm_pwm_chip *to_ehrpwm_pwm_chip(struct pwm_chip *chip)
117{
118	return pwmchip_get_drvdata(chip);
119}
120
121static inline u16 ehrpwm_read(void __iomem *base, unsigned int offset)
122{
123	return readw(base + offset);
124}
125
126static inline void ehrpwm_write(void __iomem *base, unsigned int offset,
127				u16 value)
128{
129	writew(value, base + offset);
130}
131
132static void ehrpwm_modify(void __iomem *base, unsigned int offset, u16 mask,
133			  u16 value)
134{
135	unsigned short val;
136
137	val = readw(base + offset);
138	val &= ~mask;
139	val |= value & mask;
140	writew(val, base + offset);
141}
142
143/**
144 * set_prescale_div -	Set up the prescaler divider function
145 * @rqst_prescaler:	prescaler value min
146 * @prescale_div:	prescaler value set
147 * @tb_clk_div:		Time Base Control prescaler bits
148 */
149static int set_prescale_div(unsigned long rqst_prescaler, u16 *prescale_div,
150			    u16 *tb_clk_div)
151{
152	unsigned int clkdiv, hspclkdiv;
153
154	for (clkdiv = 0; clkdiv <= CLKDIV_MAX; clkdiv++) {
155		for (hspclkdiv = 0; hspclkdiv <= HSPCLKDIV_MAX; hspclkdiv++) {
 
156			/*
157			 * calculations for prescaler value :
158			 * prescale_div = HSPCLKDIVIDER * CLKDIVIDER.
159			 * HSPCLKDIVIDER =  2 ** hspclkdiv
160			 * CLKDIVIDER = (1),		if clkdiv == 0 *OR*
161			 *		(2 * clkdiv),	if clkdiv != 0
162			 *
163			 * Configure prescale_div value such that period
164			 * register value is less than 65535.
165			 */
166
167			*prescale_div = (1 << clkdiv) *
168					(hspclkdiv ? (hspclkdiv * 2) : 1);
169			if (*prescale_div > rqst_prescaler) {
170				*tb_clk_div = (clkdiv << TBCTL_CLKDIV_SHIFT) |
171					(hspclkdiv << TBCTL_HSPCLKDIV_SHIFT);
172				return 0;
173			}
174		}
175	}
176
177	return 1;
178}
179
180static void configure_polarity(struct ehrpwm_pwm_chip *pc, int chan)
181{
182	u16 aqctl_val, aqctl_mask;
183	unsigned int aqctl_reg;
184
185	/*
186	 * Configure PWM output to HIGH/LOW level on counter
187	 * reaches compare register value and LOW/HIGH level
188	 * on counter value reaches period register value and
189	 * zero value on counter
190	 */
191	if (chan == 1) {
192		aqctl_reg = AQCTLB;
193		aqctl_mask = AQCTL_CBU_MASK;
194
195		if (pc->polarity[chan] == PWM_POLARITY_INVERSED)
196			aqctl_val = AQCTL_CHANB_POLINVERSED;
197		else
198			aqctl_val = AQCTL_CHANB_POLNORMAL;
199	} else {
200		aqctl_reg = AQCTLA;
201		aqctl_mask = AQCTL_CAU_MASK;
202
203		if (pc->polarity[chan] == PWM_POLARITY_INVERSED)
204			aqctl_val = AQCTL_CHANA_POLINVERSED;
205		else
206			aqctl_val = AQCTL_CHANA_POLNORMAL;
207	}
208
209	aqctl_mask |= AQCTL_PRD_MASK | AQCTL_ZRO_MASK;
210	ehrpwm_modify(pc->mmio_base, aqctl_reg, aqctl_mask, aqctl_val);
211}
212
213/*
214 * period_ns = 10^9 * (ps_divval * period_cycles) / PWM_CLK_RATE
215 * duty_ns   = 10^9 * (ps_divval * duty_cycles) / PWM_CLK_RATE
216 */
217static int ehrpwm_pwm_config(struct pwm_chip *chip, struct pwm_device *pwm,
218			     u64 duty_ns, u64 period_ns)
219{
220	struct ehrpwm_pwm_chip *pc = to_ehrpwm_pwm_chip(chip);
221	u32 period_cycles, duty_cycles;
222	u16 ps_divval, tb_divval;
223	unsigned int i, cmp_reg;
224	unsigned long long c;
 
 
 
225
226	if (period_ns > NSEC_PER_SEC)
227		return -ERANGE;
228
229	c = pc->clk_rate;
230	c = c * period_ns;
231	do_div(c, NSEC_PER_SEC);
232	period_cycles = (unsigned long)c;
233
234	if (period_cycles < 1) {
235		period_cycles = 1;
236		duty_cycles = 1;
237	} else {
238		c = pc->clk_rate;
239		c = c * duty_ns;
240		do_div(c, NSEC_PER_SEC);
241		duty_cycles = (unsigned long)c;
242	}
243
244	/*
245	 * Period values should be same for multiple PWM channels as IP uses
246	 * same period register for multiple channels.
247	 */
248	for (i = 0; i < NUM_PWM_CHANNEL; i++) {
249		if (pc->period_cycles[i] &&
250				(pc->period_cycles[i] != period_cycles)) {
251			/*
252			 * Allow channel to reconfigure period if no other
253			 * channels being configured.
254			 */
255			if (i == pwm->hwpwm)
256				continue;
257
258			dev_err(pwmchip_parent(chip),
259				"period value conflicts with channel %u\n",
260				i);
261			return -EINVAL;
262		}
263	}
264
265	pc->period_cycles[pwm->hwpwm] = period_cycles;
266
267	/* Configure clock prescaler to support Low frequency PWM wave */
268	if (set_prescale_div(period_cycles/PERIOD_MAX, &ps_divval,
269			     &tb_divval)) {
270		dev_err(pwmchip_parent(chip), "Unsupported values\n");
271		return -EINVAL;
272	}
273
274	pm_runtime_get_sync(pwmchip_parent(chip));
275
276	/* Update clock prescaler values */
277	ehrpwm_modify(pc->mmio_base, TBCTL, TBCTL_CLKDIV_MASK, tb_divval);
278
279	/* Update period & duty cycle with presacler division */
280	period_cycles = period_cycles / ps_divval;
281	duty_cycles = duty_cycles / ps_divval;
282
283	/* Configure shadow loading on Period register */
284	ehrpwm_modify(pc->mmio_base, TBCTL, TBCTL_PRDLD_MASK, TBCTL_PRDLD_SHDW);
285
286	ehrpwm_write(pc->mmio_base, TBPRD, period_cycles);
287
288	/* Configure ehrpwm counter for up-count mode */
289	ehrpwm_modify(pc->mmio_base, TBCTL, TBCTL_CTRMODE_MASK,
290		      TBCTL_CTRMODE_UP);
291
292	if (pwm->hwpwm == 1)
293		/* Channel 1 configured with compare B register */
294		cmp_reg = CMPB;
295	else
296		/* Channel 0 configured with compare A register */
297		cmp_reg = CMPA;
298
299	ehrpwm_write(pc->mmio_base, cmp_reg, duty_cycles);
300
301	pm_runtime_put_sync(pwmchip_parent(chip));
302
303	return 0;
304}
305
306static int ehrpwm_pwm_set_polarity(struct pwm_chip *chip,
307				   struct pwm_device *pwm,
308				   enum pwm_polarity polarity)
309{
310	struct ehrpwm_pwm_chip *pc = to_ehrpwm_pwm_chip(chip);
311
312	/* Configuration of polarity in hardware delayed, do at enable */
313	pc->polarity[pwm->hwpwm] = polarity;
314
315	return 0;
316}
317
318static int ehrpwm_pwm_enable(struct pwm_chip *chip, struct pwm_device *pwm)
319{
320	struct ehrpwm_pwm_chip *pc = to_ehrpwm_pwm_chip(chip);
321	u16 aqcsfrc_val, aqcsfrc_mask;
322	int ret;
323
324	/* Leave clock enabled on enabling PWM */
325	pm_runtime_get_sync(pwmchip_parent(chip));
326
327	/* Disabling Action Qualifier on PWM output */
328	if (pwm->hwpwm) {
329		aqcsfrc_val = AQCSFRC_CSFB_FRCDIS;
330		aqcsfrc_mask = AQCSFRC_CSFB_MASK;
331	} else {
332		aqcsfrc_val = AQCSFRC_CSFA_FRCDIS;
333		aqcsfrc_mask = AQCSFRC_CSFA_MASK;
334	}
335
336	/* Changes to shadow mode */
337	ehrpwm_modify(pc->mmio_base, AQSFRC, AQSFRC_RLDCSF_MASK,
338		      AQSFRC_RLDCSF_ZRO);
339
340	ehrpwm_modify(pc->mmio_base, AQCSFRC, aqcsfrc_mask, aqcsfrc_val);
341
342	/* Channels polarity can be configured from action qualifier module */
343	configure_polarity(pc, pwm->hwpwm);
344
345	/* Enable TBCLK */
346	ret = clk_enable(pc->tbclk);
347	if (ret) {
348		dev_err(pwmchip_parent(chip), "Failed to enable TBCLK for %s: %d\n",
349			dev_name(pwmchip_parent(chip)), ret);
350		return ret;
351	}
352
 
 
353	return 0;
354}
355
356static void ehrpwm_pwm_disable(struct pwm_chip *chip, struct pwm_device *pwm)
357{
358	struct ehrpwm_pwm_chip *pc = to_ehrpwm_pwm_chip(chip);
359	u16 aqcsfrc_val, aqcsfrc_mask;
360
361	/* Action Qualifier puts PWM output low forcefully */
362	if (pwm->hwpwm) {
363		aqcsfrc_val = AQCSFRC_CSFB_FRCLOW;
364		aqcsfrc_mask = AQCSFRC_CSFB_MASK;
365	} else {
366		aqcsfrc_val = AQCSFRC_CSFA_FRCLOW;
367		aqcsfrc_mask = AQCSFRC_CSFA_MASK;
368	}
369
370	/* Update shadow register first before modifying active register */
371	ehrpwm_modify(pc->mmio_base, AQSFRC, AQSFRC_RLDCSF_MASK,
372		      AQSFRC_RLDCSF_ZRO);
373	ehrpwm_modify(pc->mmio_base, AQCSFRC, aqcsfrc_mask, aqcsfrc_val);
374	/*
375	 * Changes to immediate action on Action Qualifier. This puts
376	 * Action Qualifier control on PWM output from next TBCLK
377	 */
378	ehrpwm_modify(pc->mmio_base, AQSFRC, AQSFRC_RLDCSF_MASK,
379		      AQSFRC_RLDCSF_IMDT);
380
381	ehrpwm_modify(pc->mmio_base, AQCSFRC, aqcsfrc_mask, aqcsfrc_val);
382
383	/* Disabling TBCLK on PWM disable */
384	clk_disable(pc->tbclk);
385
 
 
 
386	/* Disable clock on PWM disable */
387	pm_runtime_put_sync(pwmchip_parent(chip));
388}
389
390static void ehrpwm_pwm_free(struct pwm_chip *chip, struct pwm_device *pwm)
391{
392	struct ehrpwm_pwm_chip *pc = to_ehrpwm_pwm_chip(chip);
393
394	if (pwm_is_enabled(pwm)) {
395		dev_warn(pwmchip_parent(chip), "Removing PWM device without disabling\n");
396		pm_runtime_put_sync(pwmchip_parent(chip));
397	}
398
399	/* set period value to zero on free */
400	pc->period_cycles[pwm->hwpwm] = 0;
401}
402
403static int ehrpwm_pwm_apply(struct pwm_chip *chip, struct pwm_device *pwm,
404			    const struct pwm_state *state)
405{
406	int err;
407	bool enabled = pwm->state.enabled;
408
409	if (state->polarity != pwm->state.polarity) {
410		if (enabled) {
411			ehrpwm_pwm_disable(chip, pwm);
412			enabled = false;
413		}
414
415		err = ehrpwm_pwm_set_polarity(chip, pwm, state->polarity);
416		if (err)
417			return err;
418	}
419
420	if (!state->enabled) {
421		if (enabled)
422			ehrpwm_pwm_disable(chip, pwm);
423		return 0;
424	}
425
426	err = ehrpwm_pwm_config(chip, pwm, state->duty_cycle, state->period);
427	if (err)
428		return err;
429
430	if (!enabled)
431		err = ehrpwm_pwm_enable(chip, pwm);
432
433	return err;
434}
435
436static const struct pwm_ops ehrpwm_pwm_ops = {
437	.free = ehrpwm_pwm_free,
438	.apply = ehrpwm_pwm_apply,
 
 
 
 
439};
440
441static const struct of_device_id ehrpwm_of_match[] = {
442	{ .compatible = "ti,am3352-ehrpwm" },
443	{ .compatible = "ti,am33xx-ehrpwm" },
444	{},
445};
446MODULE_DEVICE_TABLE(of, ehrpwm_of_match);
447
448static int ehrpwm_pwm_probe(struct platform_device *pdev)
449{
450	struct device_node *np = pdev->dev.of_node;
 
 
451	struct ehrpwm_pwm_chip *pc;
452	struct pwm_chip *chip;
453	struct clk *clk;
454	int ret;
455
456	chip = devm_pwmchip_alloc(&pdev->dev, NUM_PWM_CHANNEL, sizeof(*pc));
457	if (IS_ERR(chip))
458		return PTR_ERR(chip);
459	pc = to_ehrpwm_pwm_chip(chip);
460
461	clk = devm_clk_get(&pdev->dev, "fck");
462	if (IS_ERR(clk)) {
463		if (of_device_is_compatible(np, "ti,am33xx-ecap")) {
464			dev_warn(&pdev->dev, "Binding is obsolete.\n");
465			clk = devm_clk_get(pdev->dev.parent, "fck");
466		}
467	}
468
469	if (IS_ERR(clk))
470		return dev_err_probe(&pdev->dev, PTR_ERR(clk), "Failed to get fck\n");
471
472	pc->clk_rate = clk_get_rate(clk);
473	if (!pc->clk_rate) {
474		dev_err(&pdev->dev, "failed to get clock rate\n");
475		return -EINVAL;
476	}
477
478	chip->ops = &ehrpwm_pwm_ops;
 
 
 
 
 
479
480	pc->mmio_base = devm_platform_ioremap_resource(pdev, 0);
 
481	if (IS_ERR(pc->mmio_base))
482		return PTR_ERR(pc->mmio_base);
483
484	/* Acquire tbclk for Time Base EHRPWM submodule */
485	pc->tbclk = devm_clk_get(&pdev->dev, "tbclk");
486	if (IS_ERR(pc->tbclk))
487		return dev_err_probe(&pdev->dev, PTR_ERR(pc->tbclk), "Failed to get tbclk\n");
 
 
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(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, chip);
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 void ehrpwm_pwm_remove(struct platform_device *pdev)
513{
514	struct pwm_chip *chip = platform_get_drvdata(pdev);
515	struct ehrpwm_pwm_chip *pc = to_ehrpwm_pwm_chip(chip);
516
517	pwmchip_remove(chip);
518
519	clk_unprepare(pc->tbclk);
 
 
 
 
 
 
520
 
521	pm_runtime_disable(&pdev->dev);
 
522}
523
524static void ehrpwm_pwm_save_context(struct pwm_chip *chip)
 
525{
526	struct ehrpwm_pwm_chip *pc = to_ehrpwm_pwm_chip(chip);
527
528	pm_runtime_get_sync(pwmchip_parent(chip));
529
530	pc->ctx.tbctl = ehrpwm_read(pc->mmio_base, TBCTL);
531	pc->ctx.tbprd = ehrpwm_read(pc->mmio_base, TBPRD);
532	pc->ctx.cmpa = ehrpwm_read(pc->mmio_base, CMPA);
533	pc->ctx.cmpb = ehrpwm_read(pc->mmio_base, CMPB);
534	pc->ctx.aqctla = ehrpwm_read(pc->mmio_base, AQCTLA);
535	pc->ctx.aqctlb = ehrpwm_read(pc->mmio_base, AQCTLB);
536	pc->ctx.aqsfrc = ehrpwm_read(pc->mmio_base, AQSFRC);
537	pc->ctx.aqcsfrc = ehrpwm_read(pc->mmio_base, AQCSFRC);
538
539	pm_runtime_put_sync(pwmchip_parent(chip));
540}
541
542static void ehrpwm_pwm_restore_context(struct pwm_chip *chip)
543{
544	struct ehrpwm_pwm_chip *pc = to_ehrpwm_pwm_chip(chip);
545
546	ehrpwm_write(pc->mmio_base, TBPRD, pc->ctx.tbprd);
547	ehrpwm_write(pc->mmio_base, CMPA, pc->ctx.cmpa);
548	ehrpwm_write(pc->mmio_base, CMPB, pc->ctx.cmpb);
549	ehrpwm_write(pc->mmio_base, AQCTLA, pc->ctx.aqctla);
550	ehrpwm_write(pc->mmio_base, AQCTLB, pc->ctx.aqctlb);
551	ehrpwm_write(pc->mmio_base, AQSFRC, pc->ctx.aqsfrc);
552	ehrpwm_write(pc->mmio_base, AQCSFRC, pc->ctx.aqcsfrc);
553	ehrpwm_write(pc->mmio_base, TBCTL, pc->ctx.tbctl);
554}
555
556static int ehrpwm_pwm_suspend(struct device *dev)
557{
558	struct pwm_chip *chip = dev_get_drvdata(dev);
559	unsigned int i;
560
561	ehrpwm_pwm_save_context(chip);
562
563	for (i = 0; i < chip->npwm; i++) {
564		struct pwm_device *pwm = &chip->pwms[i];
 
565
566		if (!pwm_is_enabled(pwm))
567			continue;
568
569		/* Disable explicitly if PWM is running */
570		pm_runtime_put_sync(dev);
571	}
572
573	return 0;
574}
575
576static int ehrpwm_pwm_resume(struct device *dev)
577{
578	struct pwm_chip *chip = dev_get_drvdata(dev);
579	unsigned int i;
580
581	for (i = 0; i < chip->npwm; i++) {
582		struct pwm_device *pwm = &chip->pwms[i];
583
584		if (!pwm_is_enabled(pwm))
585			continue;
586
587		/* Enable explicitly if PWM was running */
588		pm_runtime_get_sync(dev);
589	}
590
591	ehrpwm_pwm_restore_context(chip);
592
593	return 0;
594}
 
595
596static DEFINE_SIMPLE_DEV_PM_OPS(ehrpwm_pwm_pm_ops, ehrpwm_pwm_suspend,
597				ehrpwm_pwm_resume);
598
599static struct platform_driver ehrpwm_pwm_driver = {
600	.driver = {
601		.name = "ehrpwm",
602		.of_match_table = ehrpwm_of_match,
603		.pm = pm_ptr(&ehrpwm_pwm_pm_ops),
604	},
605	.probe = ehrpwm_pwm_probe,
606	.remove = ehrpwm_pwm_remove,
607};
 
608module_platform_driver(ehrpwm_pwm_driver);
609
610MODULE_DESCRIPTION("EHRPWM PWM driver");
611MODULE_AUTHOR("Texas Instruments");
612MODULE_LICENSE("GPL");