pwm: Drop support for legacy drivers

There are no drivers left providing the legacy callbacks. So drop
support for these.

If this commit breaks your out-of-tree pwm driver, look at e.g. commit
ec00cd5 ("pwm: renesas-tpu: Implement .apply() callback") for an
example of the needed conversion for your driver.

Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>

drivers/pwm/core.c

@@ -235,18 +235,8 @@ 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;
 
@@ -548,73 +538,6 @@ 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
@@ -647,10 +570,7 @@ int pwm_apply_state(struct pwm_device *pwm, const struct pwm_state *state)
  state->usage_power == pwm->state.usage_power)
  return 0;
 
- if (chip->ops->apply)
- err = chip->ops->apply(chip, pwm, state);
- else
- err = pwm_apply_legacy(chip, pwm, state);
+ err = chip->ops->apply(chip, pwm, state);
  if (err)
  return err;
 

include/linux/pwm.h

@@ -261,10 +261,6 @@ pwm_set_relative_duty_cycle(struct pwm_state *state, unsigned int duty_cycle,
  * called once per PWM device when the PWM chip is
  * registered.
  * @owner: helps prevent removal of modules exporting active PWMs
- * @config: configure duty cycles and period length for this PWM
- * @set_polarity: configure the polarity of this PWM
- * @enable: enable PWM output toggling
- * @disable: disable PWM output toggling
  */
 struct pwm_ops {
  int (*request)(struct pwm_chip *chip, struct pwm_device *pwm);
@@ -276,14 +272,6 @@ struct pwm_ops {
  void (*get_state)(struct pwm_chip *chip, struct pwm_device *pwm,
  struct pwm_state *state);
  struct module *owner;
-
- /* Only used by legacy drivers */
- int (*config)(struct pwm_chip *chip, struct pwm_device *pwm,
- int duty_ns, int period_ns);
- int (*set_polarity)(struct pwm_chip *chip, struct pwm_device *pwm,
- enum pwm_polarity polarity);
- int (*enable)(struct pwm_chip *chip, struct pwm_device *pwm);
- void (*disable)(struct pwm_chip *chip, struct pwm_device *pwm);
 };
 
 /**