2 * Generic pwmlib implementation
4 * Copyright (C) 2011 Sascha Hauer <s.hauer@pengutronix.de>
5 * Copyright (C) 2011-2012 Avionic Design GmbH
7 * This program is free software; you can redistribute it and/or modify
8 * it under the terms of the GNU General Public License as published by
9 * the Free Software Foundation; either version 2, or (at your option)
12 * This program is distributed in the hope that it will be useful,
13 * but WITHOUT ANY WARRANTY; without even the implied warranty of
14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
15 * GNU General Public License for more details.
17 * You should have received a copy of the GNU General Public License
18 * along with this program; see the file COPYING. If not, write to
19 * the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA.
22 #include <linux/module.h>
23 #include <linux/pwm.h>
24 #include <linux/radix-tree.h>
25 #include <linux/list.h>
26 #include <linux/mutex.h>
27 #include <linux/err.h>
28 #include <linux/slab.h>
29 #include <linux/device.h>
30 #include <linux/debugfs.h>
31 #include <linux/seq_file.h>
33 #include <dt-bindings/pwm/pwm.h>
37 static DEFINE_MUTEX(pwm_lookup_lock
);
38 static LIST_HEAD(pwm_lookup_list
);
39 static DEFINE_MUTEX(pwm_lock
);
40 static LIST_HEAD(pwm_chips
);
41 static DECLARE_BITMAP(allocated_pwms
, MAX_PWMS
);
42 static RADIX_TREE(pwm_tree
, GFP_KERNEL
);
44 static struct pwm_device
*pwm_to_device(unsigned int pwm
)
46 return radix_tree_lookup(&pwm_tree
, pwm
);
49 static int alloc_pwms(int pwm
, unsigned int count
)
51 unsigned int from
= 0;
60 start
= bitmap_find_next_zero_area(allocated_pwms
, MAX_PWMS
, from
,
63 if (pwm
>= 0 && start
!= pwm
)
66 if (start
+ count
> MAX_PWMS
)
72 static void free_pwms(struct pwm_chip
*chip
)
76 for (i
= 0; i
< chip
->npwm
; i
++) {
77 struct pwm_device
*pwm
= &chip
->pwms
[i
];
78 radix_tree_delete(&pwm_tree
, pwm
->pwm
);
81 bitmap_clear(allocated_pwms
, chip
->base
, chip
->npwm
);
87 static struct pwm_chip
*pwmchip_find_by_name(const char *name
)
89 struct pwm_chip
*chip
;
94 mutex_lock(&pwm_lock
);
96 list_for_each_entry(chip
, &pwm_chips
, list
) {
97 const char *chip_name
= dev_name(chip
->dev
);
99 if (chip_name
&& strcmp(chip_name
, name
) == 0) {
100 mutex_unlock(&pwm_lock
);
105 mutex_unlock(&pwm_lock
);
110 static int pwm_device_request(struct pwm_device
*pwm
, const char *label
)
114 if (test_bit(PWMF_REQUESTED
, &pwm
->flags
))
117 if (!try_module_get(pwm
->chip
->ops
->owner
))
120 if (pwm
->chip
->ops
->request
) {
121 err
= pwm
->chip
->ops
->request(pwm
->chip
, pwm
);
123 module_put(pwm
->chip
->ops
->owner
);
128 set_bit(PWMF_REQUESTED
, &pwm
->flags
);
132 * FIXME: This should be removed once all PWM users properly make use
133 * of struct pwm_args to initialize the PWM device. As long as this is
134 * here, the PWM state and hardware state can get out of sync.
142 of_pwm_xlate_with_flags(struct pwm_chip
*pc
, const struct of_phandle_args
*args
)
144 struct pwm_device
*pwm
;
146 if (pc
->of_pwm_n_cells
< 3)
147 return ERR_PTR(-EINVAL
);
149 if (args
->args
[0] >= pc
->npwm
)
150 return ERR_PTR(-EINVAL
);
152 pwm
= pwm_request_from_chip(pc
, args
->args
[0], NULL
);
156 pwm
->args
.period
= args
->args
[1];
158 if (args
->args
[2] & PWM_POLARITY_INVERTED
)
159 pwm
->args
.polarity
= PWM_POLARITY_INVERSED
;
161 pwm
->args
.polarity
= PWM_POLARITY_NORMAL
;
165 EXPORT_SYMBOL_GPL(of_pwm_xlate_with_flags
);
167 static struct pwm_device
*
168 of_pwm_simple_xlate(struct pwm_chip
*pc
, const struct of_phandle_args
*args
)
170 struct pwm_device
*pwm
;
172 if (pc
->of_pwm_n_cells
< 2)
173 return ERR_PTR(-EINVAL
);
175 if (args
->args
[0] >= pc
->npwm
)
176 return ERR_PTR(-EINVAL
);
178 pwm
= pwm_request_from_chip(pc
, args
->args
[0], NULL
);
182 pwm
->args
.period
= args
->args
[1];
187 static void of_pwmchip_add(struct pwm_chip
*chip
)
189 if (!chip
->dev
|| !chip
->dev
->of_node
)
192 if (!chip
->of_xlate
) {
193 chip
->of_xlate
= of_pwm_simple_xlate
;
194 chip
->of_pwm_n_cells
= 2;
197 of_node_get(chip
->dev
->of_node
);
200 static void of_pwmchip_remove(struct pwm_chip
*chip
)
203 of_node_put(chip
->dev
->of_node
);
207 * pwm_set_chip_data() - set private chip data for a PWM
209 * @data: pointer to chip-specific data
211 * Returns: 0 on success or a negative error code on failure.
213 int pwm_set_chip_data(struct pwm_device
*pwm
, void *data
)
218 pwm
->chip_data
= data
;
222 EXPORT_SYMBOL_GPL(pwm_set_chip_data
);
225 * pwm_get_chip_data() - get private chip data for a PWM
228 * Returns: A pointer to the chip-private data for the PWM device.
230 void *pwm_get_chip_data(struct pwm_device
*pwm
)
232 return pwm
? pwm
->chip_data
: NULL
;
234 EXPORT_SYMBOL_GPL(pwm_get_chip_data
);
237 * pwmchip_add_with_polarity() - register a new PWM chip
238 * @chip: the PWM chip to add
239 * @polarity: initial polarity of PWM channels
241 * Register a new PWM chip. If chip->base < 0 then a dynamically assigned base
242 * will be used. The initial polarity for all channels is specified by the
243 * @polarity parameter.
245 * Returns: 0 on success or a negative error code on failure.
247 int pwmchip_add_with_polarity(struct pwm_chip
*chip
,
248 enum pwm_polarity polarity
)
250 struct pwm_device
*pwm
;
254 if (!chip
|| !chip
->dev
|| !chip
->ops
|| !chip
->ops
->config
||
255 !chip
->ops
->enable
|| !chip
->ops
->disable
|| !chip
->npwm
)
258 mutex_lock(&pwm_lock
);
260 ret
= alloc_pwms(chip
->base
, chip
->npwm
);
264 chip
->pwms
= kzalloc(chip
->npwm
* sizeof(*pwm
), GFP_KERNEL
);
272 for (i
= 0; i
< chip
->npwm
; i
++) {
273 pwm
= &chip
->pwms
[i
];
276 pwm
->pwm
= chip
->base
+ i
;
278 pwm
->polarity
= polarity
;
279 mutex_init(&pwm
->lock
);
281 radix_tree_insert(&pwm_tree
, pwm
->pwm
, pwm
);
284 bitmap_set(allocated_pwms
, chip
->base
, chip
->npwm
);
286 INIT_LIST_HEAD(&chip
->list
);
287 list_add(&chip
->list
, &pwm_chips
);
291 if (IS_ENABLED(CONFIG_OF
))
292 of_pwmchip_add(chip
);
294 pwmchip_sysfs_export(chip
);
297 mutex_unlock(&pwm_lock
);
300 EXPORT_SYMBOL_GPL(pwmchip_add_with_polarity
);
303 * pwmchip_add() - register a new PWM chip
304 * @chip: the PWM chip to add
306 * Register a new PWM chip. If chip->base < 0 then a dynamically assigned base
307 * will be used. The initial polarity for all channels is normal.
309 * Returns: 0 on success or a negative error code on failure.
311 int pwmchip_add(struct pwm_chip
*chip
)
313 return pwmchip_add_with_polarity(chip
, PWM_POLARITY_NORMAL
);
315 EXPORT_SYMBOL_GPL(pwmchip_add
);
318 * pwmchip_remove() - remove a PWM chip
319 * @chip: the PWM chip to remove
321 * Removes a PWM chip. This function may return busy if the PWM chip provides
322 * a PWM device that is still requested.
324 * Returns: 0 on success or a negative error code on failure.
326 int pwmchip_remove(struct pwm_chip
*chip
)
331 mutex_lock(&pwm_lock
);
333 for (i
= 0; i
< chip
->npwm
; i
++) {
334 struct pwm_device
*pwm
= &chip
->pwms
[i
];
336 if (test_bit(PWMF_REQUESTED
, &pwm
->flags
)) {
342 list_del_init(&chip
->list
);
344 if (IS_ENABLED(CONFIG_OF
))
345 of_pwmchip_remove(chip
);
349 pwmchip_sysfs_unexport(chip
);
352 mutex_unlock(&pwm_lock
);
355 EXPORT_SYMBOL_GPL(pwmchip_remove
);
358 * pwm_request() - request a PWM device
359 * @pwm: global PWM device index
360 * @label: PWM device label
362 * This function is deprecated, use pwm_get() instead.
364 * Returns: A pointer to a PWM device or an ERR_PTR()-encoded error code on
367 struct pwm_device
*pwm_request(int pwm
, const char *label
)
369 struct pwm_device
*dev
;
372 if (pwm
< 0 || pwm
>= MAX_PWMS
)
373 return ERR_PTR(-EINVAL
);
375 mutex_lock(&pwm_lock
);
377 dev
= pwm_to_device(pwm
);
379 dev
= ERR_PTR(-EPROBE_DEFER
);
383 err
= pwm_device_request(dev
, label
);
388 mutex_unlock(&pwm_lock
);
392 EXPORT_SYMBOL_GPL(pwm_request
);
395 * pwm_request_from_chip() - request a PWM device relative to a PWM chip
397 * @index: per-chip index of the PWM to request
398 * @label: a literal description string of this PWM
400 * Returns: A pointer to the PWM device at the given index of the given PWM
401 * chip. A negative error code is returned if the index is not valid for the
402 * specified PWM chip or if the PWM device cannot be requested.
404 struct pwm_device
*pwm_request_from_chip(struct pwm_chip
*chip
,
408 struct pwm_device
*pwm
;
411 if (!chip
|| index
>= chip
->npwm
)
412 return ERR_PTR(-EINVAL
);
414 mutex_lock(&pwm_lock
);
415 pwm
= &chip
->pwms
[index
];
417 err
= pwm_device_request(pwm
, label
);
421 mutex_unlock(&pwm_lock
);
424 EXPORT_SYMBOL_GPL(pwm_request_from_chip
);
427 * pwm_free() - free a PWM device
430 * This function is deprecated, use pwm_put() instead.
432 void pwm_free(struct pwm_device
*pwm
)
436 EXPORT_SYMBOL_GPL(pwm_free
);
439 * pwm_config() - change a PWM device configuration
441 * @duty_ns: "on" time (in nanoseconds)
442 * @period_ns: duration (in nanoseconds) of one cycle
444 * Returns: 0 on success or a negative error code on failure.
446 int pwm_config(struct pwm_device
*pwm
, int duty_ns
, int period_ns
)
450 if (!pwm
|| duty_ns
< 0 || period_ns
<= 0 || duty_ns
> period_ns
)
453 err
= pwm
->chip
->ops
->config(pwm
->chip
, pwm
, duty_ns
, period_ns
);
457 pwm
->duty_cycle
= duty_ns
;
458 pwm
->period
= period_ns
;
462 EXPORT_SYMBOL_GPL(pwm_config
);
465 * pwm_set_polarity() - configure the polarity of a PWM signal
467 * @polarity: new polarity of the PWM signal
469 * Note that the polarity cannot be configured while the PWM device is
472 * Returns: 0 on success or a negative error code on failure.
474 int pwm_set_polarity(struct pwm_device
*pwm
, enum pwm_polarity polarity
)
478 if (!pwm
|| !pwm
->chip
->ops
)
481 if (!pwm
->chip
->ops
->set_polarity
)
484 mutex_lock(&pwm
->lock
);
486 if (pwm_is_enabled(pwm
)) {
491 err
= pwm
->chip
->ops
->set_polarity(pwm
->chip
, pwm
, polarity
);
495 pwm
->polarity
= polarity
;
498 mutex_unlock(&pwm
->lock
);
501 EXPORT_SYMBOL_GPL(pwm_set_polarity
);
504 * pwm_enable() - start a PWM output toggling
507 * Returns: 0 on success or a negative error code on failure.
509 int pwm_enable(struct pwm_device
*pwm
)
516 mutex_lock(&pwm
->lock
);
518 if (!test_and_set_bit(PWMF_ENABLED
, &pwm
->flags
)) {
519 err
= pwm
->chip
->ops
->enable(pwm
->chip
, pwm
);
521 clear_bit(PWMF_ENABLED
, &pwm
->flags
);
524 mutex_unlock(&pwm
->lock
);
528 EXPORT_SYMBOL_GPL(pwm_enable
);
531 * pwm_disable() - stop a PWM output toggling
534 void pwm_disable(struct pwm_device
*pwm
)
536 if (pwm
&& test_and_clear_bit(PWMF_ENABLED
, &pwm
->flags
))
537 pwm
->chip
->ops
->disable(pwm
->chip
, pwm
);
539 EXPORT_SYMBOL_GPL(pwm_disable
);
541 static struct pwm_chip
*of_node_to_pwmchip(struct device_node
*np
)
543 struct pwm_chip
*chip
;
545 mutex_lock(&pwm_lock
);
547 list_for_each_entry(chip
, &pwm_chips
, list
)
548 if (chip
->dev
&& chip
->dev
->of_node
== np
) {
549 mutex_unlock(&pwm_lock
);
553 mutex_unlock(&pwm_lock
);
555 return ERR_PTR(-EPROBE_DEFER
);
559 * of_pwm_get() - request a PWM via the PWM framework
560 * @np: device node to get the PWM from
561 * @con_id: consumer name
563 * Returns the PWM device parsed from the phandle and index specified in the
564 * "pwms" property of a device tree node or a negative error-code on failure.
565 * Values parsed from the device tree are stored in the returned PWM device
568 * If con_id is NULL, the first PWM device listed in the "pwms" property will
569 * be requested. Otherwise the "pwm-names" property is used to do a reverse
570 * lookup of the PWM index. This also means that the "pwm-names" property
571 * becomes mandatory for devices that look up the PWM device via the con_id
574 * Returns: A pointer to the requested PWM device or an ERR_PTR()-encoded
575 * error code on failure.
577 struct pwm_device
*of_pwm_get(struct device_node
*np
, const char *con_id
)
579 struct pwm_device
*pwm
= NULL
;
580 struct of_phandle_args args
;
586 index
= of_property_match_string(np
, "pwm-names", con_id
);
588 return ERR_PTR(index
);
591 err
= of_parse_phandle_with_args(np
, "pwms", "#pwm-cells", index
,
594 pr_debug("%s(): can't parse \"pwms\" property\n", __func__
);
598 pc
= of_node_to_pwmchip(args
.np
);
600 pr_debug("%s(): PWM chip not found\n", __func__
);
605 if (args
.args_count
!= pc
->of_pwm_n_cells
) {
606 pr_debug("%s: wrong #pwm-cells for %s\n", np
->full_name
,
608 pwm
= ERR_PTR(-EINVAL
);
612 pwm
= pc
->of_xlate(pc
, &args
);
617 * If a consumer name was not given, try to look it up from the
618 * "pwm-names" property if it exists. Otherwise use the name of
619 * the user device node.
622 err
= of_property_read_string_index(np
, "pwm-names", index
,
631 of_node_put(args
.np
);
635 EXPORT_SYMBOL_GPL(of_pwm_get
);
638 * pwm_add_table() - register PWM device consumers
639 * @table: array of consumers to register
640 * @num: number of consumers in table
642 void pwm_add_table(struct pwm_lookup
*table
, size_t num
)
644 mutex_lock(&pwm_lookup_lock
);
647 list_add_tail(&table
->list
, &pwm_lookup_list
);
651 mutex_unlock(&pwm_lookup_lock
);
655 * pwm_remove_table() - unregister PWM device consumers
656 * @table: array of consumers to unregister
657 * @num: number of consumers in table
659 void pwm_remove_table(struct pwm_lookup
*table
, size_t num
)
661 mutex_lock(&pwm_lookup_lock
);
664 list_del(&table
->list
);
668 mutex_unlock(&pwm_lookup_lock
);
672 * pwm_get() - look up and request a PWM device
673 * @dev: device for PWM consumer
674 * @con_id: consumer name
676 * Lookup is first attempted using DT. If the device was not instantiated from
677 * a device tree, a PWM chip and a relative index is looked up via a table
678 * supplied by board setup code (see pwm_add_table()).
680 * Once a PWM chip has been found the specified PWM device will be requested
681 * and is ready to be used.
683 * Returns: A pointer to the requested PWM device or an ERR_PTR()-encoded
684 * error code on failure.
686 struct pwm_device
*pwm_get(struct device
*dev
, const char *con_id
)
688 struct pwm_device
*pwm
= ERR_PTR(-EPROBE_DEFER
);
689 const char *dev_id
= dev
? dev_name(dev
) : NULL
;
690 struct pwm_chip
*chip
= NULL
;
691 unsigned int best
= 0;
692 struct pwm_lookup
*p
, *chosen
= NULL
;
695 /* look up via DT first */
696 if (IS_ENABLED(CONFIG_OF
) && dev
&& dev
->of_node
)
697 return of_pwm_get(dev
->of_node
, con_id
);
700 * We look up the provider in the static table typically provided by
701 * board setup code. We first try to lookup the consumer device by
702 * name. If the consumer device was passed in as NULL or if no match
703 * was found, we try to find the consumer by directly looking it up
706 * If a match is found, the provider PWM chip is looked up by name
707 * and a PWM device is requested using the PWM device per-chip index.
709 * The lookup algorithm was shamelessly taken from the clock
712 * We do slightly fuzzy matching here:
713 * An entry with a NULL ID is assumed to be a wildcard.
714 * If an entry has a device ID, it must match
715 * If an entry has a connection ID, it must match
716 * Then we take the most specific entry - with the following order
717 * of precedence: dev+con > dev only > con only.
719 mutex_lock(&pwm_lookup_lock
);
721 list_for_each_entry(p
, &pwm_lookup_list
, list
) {
725 if (!dev_id
|| strcmp(p
->dev_id
, dev_id
))
732 if (!con_id
|| strcmp(p
->con_id
, con_id
))
749 pwm
= ERR_PTR(-ENODEV
);
753 chip
= pwmchip_find_by_name(chosen
->provider
);
757 pwm
->args
.period
= chosen
->period
;
758 pwm
->args
.polarity
= chosen
->polarity
;
760 pwm
= pwm_request_from_chip(chip
, chosen
->index
, con_id
?: dev_id
);
765 mutex_unlock(&pwm_lookup_lock
);
768 EXPORT_SYMBOL_GPL(pwm_get
);
771 * pwm_put() - release a PWM device
774 void pwm_put(struct pwm_device
*pwm
)
779 mutex_lock(&pwm_lock
);
781 if (!test_and_clear_bit(PWMF_REQUESTED
, &pwm
->flags
)) {
782 pr_warn("PWM device already freed\n");
786 if (pwm
->chip
->ops
->free
)
787 pwm
->chip
->ops
->free(pwm
->chip
, pwm
);
791 module_put(pwm
->chip
->ops
->owner
);
793 mutex_unlock(&pwm_lock
);
795 EXPORT_SYMBOL_GPL(pwm_put
);
797 static void devm_pwm_release(struct device
*dev
, void *res
)
799 pwm_put(*(struct pwm_device
**)res
);
803 * devm_pwm_get() - resource managed pwm_get()
804 * @dev: device for PWM consumer
805 * @con_id: consumer name
807 * This function performs like pwm_get() but the acquired PWM device will
808 * automatically be released on driver detach.
810 * Returns: A pointer to the requested PWM device or an ERR_PTR()-encoded
811 * error code on failure.
813 struct pwm_device
*devm_pwm_get(struct device
*dev
, const char *con_id
)
815 struct pwm_device
**ptr
, *pwm
;
817 ptr
= devres_alloc(devm_pwm_release
, sizeof(*ptr
), GFP_KERNEL
);
819 return ERR_PTR(-ENOMEM
);
821 pwm
= pwm_get(dev
, con_id
);
824 devres_add(dev
, ptr
);
831 EXPORT_SYMBOL_GPL(devm_pwm_get
);
834 * devm_of_pwm_get() - resource managed of_pwm_get()
835 * @dev: device for PWM consumer
836 * @np: device node to get the PWM from
837 * @con_id: consumer name
839 * This function performs like of_pwm_get() but the acquired PWM device will
840 * automatically be released on driver detach.
842 * Returns: A pointer to the requested PWM device or an ERR_PTR()-encoded
843 * error code on failure.
845 struct pwm_device
*devm_of_pwm_get(struct device
*dev
, struct device_node
*np
,
848 struct pwm_device
**ptr
, *pwm
;
850 ptr
= devres_alloc(devm_pwm_release
, sizeof(*ptr
), GFP_KERNEL
);
852 return ERR_PTR(-ENOMEM
);
854 pwm
= of_pwm_get(np
, con_id
);
857 devres_add(dev
, ptr
);
864 EXPORT_SYMBOL_GPL(devm_of_pwm_get
);
866 static int devm_pwm_match(struct device
*dev
, void *res
, void *data
)
868 struct pwm_device
**p
= res
;
870 if (WARN_ON(!p
|| !*p
))
877 * devm_pwm_put() - resource managed pwm_put()
878 * @dev: device for PWM consumer
881 * Release a PWM previously allocated using devm_pwm_get(). Calling this
882 * function is usually not needed because devm-allocated resources are
883 * automatically released on driver detach.
885 void devm_pwm_put(struct device
*dev
, struct pwm_device
*pwm
)
887 WARN_ON(devres_release(dev
, devm_pwm_release
, devm_pwm_match
, pwm
));
889 EXPORT_SYMBOL_GPL(devm_pwm_put
);
892 * pwm_can_sleep() - report whether PWM access will sleep
895 * Returns: True if accessing the PWM can sleep, false otherwise.
897 bool pwm_can_sleep(struct pwm_device
*pwm
)
901 EXPORT_SYMBOL_GPL(pwm_can_sleep
);
903 #ifdef CONFIG_DEBUG_FS
904 static void pwm_dbg_show(struct pwm_chip
*chip
, struct seq_file
*s
)
908 for (i
= 0; i
< chip
->npwm
; i
++) {
909 struct pwm_device
*pwm
= &chip
->pwms
[i
];
911 seq_printf(s
, " pwm-%-3d (%-20.20s):", i
, pwm
->label
);
913 if (test_bit(PWMF_REQUESTED
, &pwm
->flags
))
914 seq_puts(s
, " requested");
916 if (pwm_is_enabled(pwm
))
917 seq_puts(s
, " enabled");
923 static void *pwm_seq_start(struct seq_file
*s
, loff_t
*pos
)
925 mutex_lock(&pwm_lock
);
928 return seq_list_start(&pwm_chips
, *pos
);
931 static void *pwm_seq_next(struct seq_file
*s
, void *v
, loff_t
*pos
)
935 return seq_list_next(v
, &pwm_chips
, pos
);
938 static void pwm_seq_stop(struct seq_file
*s
, void *v
)
940 mutex_unlock(&pwm_lock
);
943 static int pwm_seq_show(struct seq_file
*s
, void *v
)
945 struct pwm_chip
*chip
= list_entry(v
, struct pwm_chip
, list
);
947 seq_printf(s
, "%s%s/%s, %d PWM device%s\n", (char *)s
->private,
948 chip
->dev
->bus
? chip
->dev
->bus
->name
: "no-bus",
949 dev_name(chip
->dev
), chip
->npwm
,
950 (chip
->npwm
!= 1) ? "s" : "");
952 if (chip
->ops
->dbg_show
)
953 chip
->ops
->dbg_show(chip
, s
);
955 pwm_dbg_show(chip
, s
);
960 static const struct seq_operations pwm_seq_ops
= {
961 .start
= pwm_seq_start
,
962 .next
= pwm_seq_next
,
963 .stop
= pwm_seq_stop
,
964 .show
= pwm_seq_show
,
967 static int pwm_seq_open(struct inode
*inode
, struct file
*file
)
969 return seq_open(file
, &pwm_seq_ops
);
972 static const struct file_operations pwm_debugfs_ops
= {
973 .owner
= THIS_MODULE
,
974 .open
= pwm_seq_open
,
977 .release
= seq_release
,
980 static int __init
pwm_debugfs_init(void)
982 debugfs_create_file("pwm", S_IFREG
| S_IRUGO
, NULL
, NULL
,
987 subsys_initcall(pwm_debugfs_init
);
988 #endif /* CONFIG_DEBUG_FS */