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Diffstat (limited to 'include/linux/pwm.h')
-rw-r--r--include/linux/pwm.h34
1 files changed, 29 insertions, 5 deletions
diff --git a/include/linux/pwm.h b/include/linux/pwm.h
index 6853e29d9674..8cafc483db53 100644
--- a/include/linux/pwm.h
+++ b/include/linux/pwm.h
@@ -2,6 +2,7 @@
#ifndef __LINUX_PWM_H
#define __LINUX_PWM_H
+#include <linux/cdev.h>
#include <linux/device.h>
#include <linux/err.h>
#include <linux/module.h>
@@ -218,6 +219,8 @@ static inline void pwm_init_state(const struct pwm_device *pwm,
*
* pwm_get_state(pwm, &state);
* duty = pwm_get_relative_duty_cycle(&state, 100);
+ *
+ * Returns: rounded relative duty cycle multiplied by @scale
*/
static inline unsigned int
pwm_get_relative_duty_cycle(const struct pwm_state *state, unsigned int scale)
@@ -244,8 +247,8 @@ pwm_get_relative_duty_cycle(const struct pwm_state *state, unsigned int scale)
* pwm_set_relative_duty_cycle(&state, 50, 100);
* pwm_apply_might_sleep(pwm, &state);
*
- * This functions returns -EINVAL if @duty_cycle and/or @scale are
- * inconsistent (@scale == 0 or @duty_cycle > @scale).
+ * Returns: 0 on success or ``-EINVAL`` if @duty_cycle and/or @scale are
+ * inconsistent (@scale == 0 or @duty_cycle > @scale)
*/
static inline int
pwm_set_relative_duty_cycle(struct pwm_state *state, unsigned int duty_cycle,
@@ -271,6 +274,8 @@ struct pwm_capture {
unsigned int duty_cycle;
};
+#define PWM_WFHWSIZE 20
+
/**
* struct pwm_ops - PWM controller operations
* @request: optional hook for requesting a PWM
@@ -309,6 +314,7 @@ struct pwm_ops {
/**
* struct pwm_chip - abstract a PWM controller
* @dev: device providing the PWMs
+ * @cdev: &struct cdev for this device
* @ops: callbacks for this PWM controller
* @owner: module providing this chip
* @id: unique number of this PWM chip
@@ -323,6 +329,7 @@ struct pwm_ops {
*/
struct pwm_chip {
struct device dev;
+ struct cdev cdev;
const struct pwm_ops *ops;
struct module *owner;
unsigned int id;
@@ -347,12 +354,29 @@ struct pwm_chip {
struct pwm_device pwms[] __counted_by(npwm);
};
+/**
+ * pwmchip_supports_waveform() - checks if the given chip supports waveform callbacks
+ * @chip: The pwm_chip to test
+ *
+ * Returns: true iff the pwm chip support the waveform functions like
+ * pwm_set_waveform_might_sleep() and pwm_round_waveform_might_sleep()
+ */
+static inline bool pwmchip_supports_waveform(struct pwm_chip *chip)
+{
+ /*
+ * only check for .write_waveform(). If that is available,
+ * .round_waveform_tohw() and .round_waveform_fromhw() asserted to be
+ * available, too, in pwmchip_add().
+ */
+ return chip->ops->write_waveform != NULL;
+}
+
static inline struct device *pwmchip_parent(const struct pwm_chip *chip)
{
return chip->dev.parent;
}
-static inline void *pwmchip_get_drvdata(struct pwm_chip *chip)
+static inline void *pwmchip_get_drvdata(const struct pwm_chip *chip)
{
return dev_get_drvdata(&chip->dev);
}
@@ -362,7 +386,7 @@ static inline void pwmchip_set_drvdata(struct pwm_chip *chip, void *data)
dev_set_drvdata(&chip->dev, data);
}
-#if IS_ENABLED(CONFIG_PWM)
+#if IS_REACHABLE(CONFIG_PWM)
/* PWM consumer APIs */
int pwm_round_waveform_might_sleep(struct pwm_device *pwm, struct pwm_waveform *wf);
@@ -644,7 +668,7 @@ struct pwm_lookup {
PWM_LOOKUP_WITH_MODULE(_provider, _index, _dev_id, _con_id, _period, \
_polarity, NULL)
-#if IS_ENABLED(CONFIG_PWM)
+#if IS_REACHABLE(CONFIG_PWM)
void pwm_add_table(struct pwm_lookup *table, size_t num);
void pwm_remove_table(struct pwm_lookup *table, size_t num);
#else