pwm: core: Add option to config PWM duty/period with u64 data length
Currently, PWM core driver provides interfaces for configuring PWM
period and duty length in nanoseconds with an integer data type, so
the max period can be only set to ~2.147 seconds. Add interfaces which
can set PWM period and duty with u64 data type to remove this
limitation.
Change-Id: Ic8722088510d447fc939ab6a5014711aef1b832f
Signed-off-by: Fenglin Wu <fenglinw@codeaurora.org>
diff --git a/include/linux/pwm.h b/include/linux/pwm.h
index 6c0168b..b40287e 100644
--- a/include/linux/pwm.h
+++ b/include/linux/pwm.h
@@ -38,7 +38,7 @@
* current PWM hardware state.
*/
struct pwm_args {
- unsigned int period;
+ u64 period;
enum pwm_polarity polarity;
};
@@ -65,9 +65,9 @@
* @cycles_per_duty: number of PWM period cycles an entry stays at
*/
struct pwm_output_pattern {
- unsigned int *duty_pattern;
+ u64 *duty_pattern;
unsigned int num_entries;
- unsigned int cycles_per_duty;
+ u64 cycles_per_duty;
};
/*
@@ -78,8 +78,8 @@
* @enabled: PWM enabled status
*/
struct pwm_state {
- unsigned int period;
- unsigned int duty_cycle;
+ u64 period;
+ u64 duty_cycle;
enum pwm_polarity polarity;
enum pwm_output_type output_type;
struct pwm_output_pattern *output_pattern;
@@ -135,12 +135,30 @@
pwm->state.period = period;
}
+static inline void pwm_set_period_extend(struct pwm_device *pwm, u64 period)
+{
+ if (pwm)
+ pwm->state.period = period;
+}
+
static inline unsigned int pwm_get_period(const struct pwm_device *pwm)
{
struct pwm_state state;
pwm_get_state(pwm, &state);
+ if (state.period > UINT_MAX)
+ pr_warn("PWM period %llu is truncated\n", state.period);
+
+ return (unsigned int)state.period;
+}
+
+static inline u64 pwm_get_period_extend(const struct pwm_device *pwm)
+{
+ struct pwm_state state;
+
+ pwm_get_state(pwm, &state);
+
return state.period;
}
@@ -150,12 +168,30 @@
pwm->state.duty_cycle = duty;
}
+static inline void pwm_set_duty_cycle_extend(struct pwm_device *pwm, u64 duty)
+{
+ if (pwm)
+ pwm->state.duty_cycle = duty;
+}
+
static inline unsigned int pwm_get_duty_cycle(const struct pwm_device *pwm)
{
struct pwm_state state;
pwm_get_state(pwm, &state);
+ if (state.duty_cycle > UINT_MAX)
+ pr_warn("PWM duty cycle %llu is truncated\n", state.duty_cycle);
+
+ return (unsigned int)state.duty_cycle;
+}
+
+static inline u64 pwm_get_duty_cycle_extend(const struct pwm_device *pwm)
+{
+ struct pwm_state state;
+
+ pwm_get_state(pwm, &state);
+
return state.duty_cycle;
}
@@ -287,6 +323,8 @@
* @request: optional hook for requesting a PWM
* @free: optional hook for freeing a PWM
* @config: configure duty cycles and period length for this PWM
+ * @config_extend: configure duty cycles and period length for this
+ * PWM with u64 data type
* @set_polarity: configure the polarity of this PWM
* @capture: capture and report PWM signal
* @enable: enable PWM output toggling
@@ -309,6 +347,8 @@
void (*free)(struct pwm_chip *chip, struct pwm_device *pwm);
int (*config)(struct pwm_chip *chip, struct pwm_device *pwm,
int duty_ns, int period_ns);
+ int (*config_extend)(struct pwm_chip *chip, struct pwm_device *pwm,
+ u64 duty_ns, u64 period_ns);
int (*set_polarity)(struct pwm_chip *chip, struct pwm_device *pwm,
enum pwm_polarity polarity);
int (*capture)(struct pwm_chip *chip, struct pwm_device *pwm,
@@ -366,8 +406,8 @@
* @duty_cycle: duty cycle of the PWM signal (in nanoseconds)
*/
struct pwm_capture {
- unsigned int period;
- unsigned int duty_cycle;
+ u64 period;
+ u64 duty_cycle;
};
#if IS_ENABLED(CONFIG_PWM)
@@ -421,6 +461,31 @@
}
/**
+ * pwm_config_extend() - change PWM period and duty length with u64 data type
+ * @pwm: PWM device
+ * @duty_ns: "on" time (in nanoseconds)
+ * @period_ns: duration (in nanoseconds) of one cycle
+ *
+ * Returns: 0 on success or a negative error code on failure.
+ */
+static inline int pwm_config_extend(struct pwm_device *pwm, u64 duty_ns,
+ u64 period_ns)
+{
+ struct pwm_state state;
+
+ if (!pwm)
+ return -EINVAL;
+
+ pwm_get_state(pwm, &state);
+ if (state.duty_cycle == duty_ns && state.period == period_ns)
+ return 0;
+
+ state.duty_cycle = duty_ns;
+ state.period = period_ns;
+ return pwm_apply_state(pwm, &state);
+}
+
+/**
* pwm_set_polarity() - configure the polarity of a PWM signal
* @pwm: PWM device
* @polarity: new polarity of the PWM signal