[PATCH v3 03/12] pwm: move the enabled/disabled info to pwm_state struct

From: Boris Brezillon
Date: Mon Sep 21 2015 - 05:38:34 EST


Prepare the transition to PWM atomic update by moving the enabled/disabled
state into the pwm_state struct. This way we can easily update the whole
PWM state by copying the new state in the ->state field.

Signed-off-by: Boris Brezillon <boris.brezillon@xxxxxxxxxxxxxxxxxx>
---
drivers/pwm/core.c | 15 ++++++++++++---
include/linux/pwm.h | 7 ++++---
2 files changed, 16 insertions(+), 6 deletions(-)

diff --git a/drivers/pwm/core.c b/drivers/pwm/core.c
index 09037de..963238c3 100644
--- a/drivers/pwm/core.c
+++ b/drivers/pwm/core.c
@@ -494,8 +494,15 @@ EXPORT_SYMBOL_GPL(pwm_set_polarity);
*/
int pwm_enable(struct pwm_device *pwm)
{
- if (pwm && !test_and_set_bit(PWMF_ENABLED, &pwm->flags))
- return pwm->chip->ops->enable(pwm->chip, pwm);
+ if (pwm && !pwm_is_enabled(pwm)) {
+ int err;
+
+ err = pwm->chip->ops->enable(pwm->chip, pwm);
+ if (!err)
+ pwm->state.enabled = true;
+
+ return err;
+ }

return pwm ? 0 : -EINVAL;
}
@@ -507,8 +514,10 @@ EXPORT_SYMBOL_GPL(pwm_enable);
*/
void pwm_disable(struct pwm_device *pwm)
{
- if (pwm && test_and_clear_bit(PWMF_ENABLED, &pwm->flags))
+ if (pwm && pwm_is_enabled(pwm)) {
pwm->chip->ops->disable(pwm->chip, pwm);
+ pwm->state.enabled = false;
+ }
}
EXPORT_SYMBOL_GPL(pwm_disable);

diff --git a/include/linux/pwm.h b/include/linux/pwm.h
index e0e0ed8..433a097 100644
--- a/include/linux/pwm.h
+++ b/include/linux/pwm.h
@@ -75,8 +75,7 @@ enum pwm_polarity {

enum {
PWMF_REQUESTED = 1 << 0,
- PWMF_ENABLED = 1 << 1,
- PWMF_EXPORTED = 1 << 2,
+ PWMF_EXPORTED = 1 << 1,
};

/*
@@ -84,11 +83,13 @@ enum {
* @period: PWM period (in nanoseconds)
* @duty_cycle: PWM duty cycle (in nanoseconds)
* @polarity: PWM polarity
+ * @enabled: PWM enabled status
*/
struct pwm_state {
unsigned int period;
unsigned int duty_cycle;
enum pwm_polarity polarity;
+ bool enabled;
};

/**
@@ -114,7 +115,7 @@ struct pwm_device {

static inline bool pwm_is_enabled(const struct pwm_device *pwm)
{
- return test_bit(PWMF_ENABLED, &pwm->flags);
+ return pwm->state.enabled;
}

static inline void pwm_set_period(struct pwm_device *pwm, unsigned int period)
--
1.9.1

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