diff options
| -rw-r--r-- | drivers/pwm/core.c | 40 | ||||
| -rw-r--r-- | include/linux/pwm.h | 6 |
2 files changed, 33 insertions, 13 deletions
diff --git a/drivers/pwm/core.c b/drivers/pwm/core.c index 4399e793efaf..ccbdd6dd1410 100644 --- a/drivers/pwm/core.c +++ b/drivers/pwm/core.c @@ -718,40 +718,54 @@ int pwm_apply_atomic(struct pwm_device *pwm, const struct pwm_state *state) } EXPORT_SYMBOL_GPL(pwm_apply_atomic); -static int pwm_get_state_hw(struct pwm_device *pwm, struct pwm_state *state) +/** + * pwm_get_state_hw() - get the current PWM state from hardware + * @pwm: PWM device + * @state: state to fill with the current PWM state + * + * Similar to pwm_get_state() but reads the current PWM state from hardware + * instead of the requested state. + * + * Returns: 0 on success or a negative error code on failure. + * Context: May sleep. + */ +int pwm_get_state_hw(struct pwm_device *pwm, struct pwm_state *state) { struct pwm_chip *chip = pwm->chip; const struct pwm_ops *ops = chip->ops; int ret = -EOPNOTSUPP; + might_sleep(); + + guard(pwmchip)(chip); + + if (!chip->operational) + return -ENODEV; + if (ops->read_waveform) { char wfhw[WFHWSIZE]; struct pwm_waveform wf; BUG_ON(WFHWSIZE < ops->sizeof_wfhw); - scoped_guard(pwmchip, chip) { + ret = __pwm_read_waveform(chip, pwm, &wfhw); + if (ret) + return ret; - ret = __pwm_read_waveform(chip, pwm, &wfhw); - if (ret) - return ret; - - ret = __pwm_round_waveform_fromhw(chip, pwm, &wfhw, &wf); - if (ret) - return ret; - } + ret = __pwm_round_waveform_fromhw(chip, pwm, &wfhw, &wf); + if (ret) + return ret; pwm_wf2state(&wf, state); } else if (ops->get_state) { - scoped_guard(pwmchip, chip) - ret = ops->get_state(chip, pwm, state); - + ret = ops->get_state(chip, pwm, state); trace_pwm_get(pwm, state, ret); } return ret; } +EXPORT_SYMBOL_GPL(pwm_get_state_hw); /** * pwm_adjust_config() - adjust the current PWM config to the PWM arguments diff --git a/include/linux/pwm.h b/include/linux/pwm.h index f1cb1e5b0a36..78827f312407 100644 --- a/include/linux/pwm.h +++ b/include/linux/pwm.h @@ -370,6 +370,7 @@ int pwm_get_waveform_might_sleep(struct pwm_device *pwm, struct pwm_waveform *wf int pwm_set_waveform_might_sleep(struct pwm_device *pwm, const struct pwm_waveform *wf, bool exact); int pwm_apply_might_sleep(struct pwm_device *pwm, const struct pwm_state *state); int pwm_apply_atomic(struct pwm_device *pwm, const struct pwm_state *state); +int pwm_get_state_hw(struct pwm_device *pwm, struct pwm_state *state); int pwm_adjust_config(struct pwm_device *pwm); /** @@ -494,6 +495,11 @@ static inline int pwm_apply_atomic(struct pwm_device *pwm, return -EOPNOTSUPP; } +static inline int pwm_get_state_hw(struct pwm_device *pwm, struct pwm_state *state) +{ + return -EOPNOTSUPP; +} + static inline int pwm_adjust_config(struct pwm_device *pwm) { return -EOPNOTSUPP; |