vfs: do bulk POLL* -> EPOLL* replacement
[sfrench/cifs-2.6.git] / drivers / pwm / pwm-tiehrpwm.c
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
113 struct 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
124 struct 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
134 static 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
139 static inline u16 ehrpwm_read(void __iomem *base, unsigned int offset)
140 {
141         return readw(base + offset);
142 }
143
144 static inline void ehrpwm_write(void __iomem *base, unsigned int offset,
145                                 u16 value)
146 {
147         writew(value, base + offset);
148 }
149
150 static 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  */
167 static 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
198 static 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  */
235 static 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
324 static 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
336 static 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
377 static 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
410 static 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
423 static 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
432 static const struct of_device_id ehrpwm_of_match[] = {
433         { .compatible = "ti,am3352-ehrpwm" },
434         { .compatible = "ti,am33xx-ehrpwm" },
435         {},
436 };
437 MODULE_DEVICE_TABLE(of, ehrpwm_of_match);
438
439 static 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
506 err_clk_unprepare:
507         clk_unprepare(pc->tbclk);
508
509         return ret;
510 }
511
512 static 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
524 static 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
540 static 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
552 static 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
572 static 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
593 static SIMPLE_DEV_PM_OPS(ehrpwm_pwm_pm_ops, ehrpwm_pwm_suspend,
594                          ehrpwm_pwm_resume);
595
596 static 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 };
605 module_platform_driver(ehrpwm_pwm_driver);
606
607 MODULE_DESCRIPTION("EHRPWM PWM driver");
608 MODULE_AUTHOR("Texas Instruments");
609 MODULE_LICENSE("GPL");