Your Name
106 lines
2.6 KiB
Diff
Executable File
106 lines
2.6 KiB
Diff
Executable File
diff --git a/drivers/pwm/core.c b/drivers/pwm/core.c
|
|
index d333e7422f4a..f586deaf9d38 100644
|
|
--- a/drivers/pwm/core.c
|
|
+++ b/drivers/pwm/core.c
|
|
@@ -236,7 +236,14 @@ EXPORT_SYMBOL_GPL(pwm_get_chip_data);
|
|
static bool pwm_ops_check(const struct pwm_chip *chip)
|
|
{
|
|
const struct pwm_ops *ops = chip->ops;
|
|
+ /* driver supports legacy, non-atomic operation */
|
|
+ if (ops->config && ops->enable && ops->disable) {
|
|
+ if (IS_ENABLED(CONFIG_PWM_DEBUG))
|
|
+ dev_warn(chip->dev,
|
|
+ "Driver needs updating to atomic API\n");
|
|
|
|
+ return true;
|
|
+ }
|
|
if (!ops->apply)
|
|
return false;
|
|
|
|
@@ -538,6 +545,73 @@ static void pwm_apply_state_debug(struct pwm_device *pwm,
|
|
}
|
|
}
|
|
|
|
+static int pwm_apply_legacy(struct pwm_chip *chip, struct pwm_device *pwm,
|
|
+ const struct pwm_state *state)
|
|
+{
|
|
+ int err;
|
|
+ struct pwm_state initial_state = pwm->state;
|
|
+
|
|
+ if (state->polarity != pwm->state.polarity) {
|
|
+ if (!chip->ops->set_polarity)
|
|
+ return -EINVAL;
|
|
+
|
|
+ /*
|
|
+ * Changing the polarity of a running PWM is only allowed when
|
|
+ * the PWM driver implements ->apply().
|
|
+ */
|
|
+ if (pwm->state.enabled) {
|
|
+ chip->ops->disable(chip, pwm);
|
|
+
|
|
+ /*
|
|
+ * Update pwm->state already here in case
|
|
+ * .set_polarity() or another callback depend on that.
|
|
+ */
|
|
+ pwm->state.enabled = false;
|
|
+ }
|
|
+
|
|
+ err = chip->ops->set_polarity(chip, pwm, state->polarity);
|
|
+ if (err)
|
|
+ goto rollback;
|
|
+
|
|
+ pwm->state.polarity = state->polarity;
|
|
+ }
|
|
+
|
|
+ if (!state->enabled) {
|
|
+ if (pwm->state.enabled)
|
|
+ chip->ops->disable(chip, pwm);
|
|
+
|
|
+ return 0;
|
|
+ }
|
|
+
|
|
+ /*
|
|
+ * We cannot skip calling ->config even if state->period ==
|
|
+ * pwm->state.period && state->duty_cycle == pwm->state.duty_cycle
|
|
+ * because we might have exited early in the last call to
|
|
+ * pwm_apply_state because of !state->enabled and so the two values in
|
|
+ * pwm->state might not be configured in hardware.
|
|
+ */
|
|
+ err = chip->ops->config(pwm->chip, pwm,
|
|
+ state->duty_cycle,
|
|
+ state->period);
|
|
+ if (err)
|
|
+ goto rollback;
|
|
+
|
|
+ pwm->state.period = state->period;
|
|
+ pwm->state.duty_cycle = state->duty_cycle;
|
|
+
|
|
+ if (!pwm->state.enabled) {
|
|
+ err = chip->ops->enable(chip, pwm);
|
|
+ if (err)
|
|
+ goto rollback;
|
|
+ }
|
|
+
|
|
+ return 0;
|
|
+
|
|
+rollback:
|
|
+ pwm->state = initial_state;
|
|
+ return err;
|
|
+}
|
|
+
|
|
/**
|
|
* pwm_apply_state() - atomically apply a new state to a PWM device
|
|
* @pwm: PWM device
|
|
@@ -570,7 +644,10 @@ int pwm_apply_state(struct pwm_device *pwm, const struct pwm_state *state)
|
|
state->usage_power == pwm->state.usage_power)
|
|
return 0;
|
|
|
|
- err = chip->ops->apply(chip, pwm, state);
|
|
+ if (chip->ops->apply)
|
|
+ err = chip->ops->apply(chip, pwm, state);
|
|
+ else
|
|
+ err = pwm_apply_legacy(chip, pwm, state);
|
|
if (err)
|
|
return err;
|
|
|