diff options
Diffstat (limited to 'include/linux')
| -rw-r--r-- | include/linux/pwm.h | 36 |
1 files changed, 36 insertions, 0 deletions
diff --git a/include/linux/pwm.h b/include/linux/pwm.h index 3ea73e075abe..d8cfe1c9b19d 100644 --- a/include/linux/pwm.h +++ b/include/linux/pwm.h @@ -49,6 +49,31 @@ enum { PWMF_EXPORTED = 1, }; +/** + * struct pwm_waveform - description of a PWM waveform + * @period_length_ns: PWM period + * @duty_length_ns: PWM duty cycle + * @duty_offset_ns: offset of the rising edge from the period's start + * + * This is a representation of a PWM waveform alternative to struct pwm_state + * below. It's more expressive than struct pwm_state as it contains a + * duty_offset_ns and so can represent offsets other than zero (with .polarity = + * PWM_POLARITY_NORMAL) and period - duty_cycle (.polarity = + * PWM_POLARITY_INVERSED). + * + * Note there is no explicit bool for enabled. A "disabled" PWM is represented + * by .period_length_ns = 0. Note further that the behaviour of a "disabled" PWM + * is undefined. Depending on the hardware's capabilities it might drive the + * active or inactive level, go high-z or even continue to toggle. + * + * The unit for all three members is nanoseconds. + */ +struct pwm_waveform { + u64 period_length_ns; + u64 duty_length_ns; + u64 duty_offset_ns; +}; + /* * struct pwm_state - state of a PWM channel * @period: PWM period (in nanoseconds) @@ -259,6 +284,17 @@ struct pwm_ops { void (*free)(struct pwm_chip *chip, struct pwm_device *pwm); int (*capture)(struct pwm_chip *chip, struct pwm_device *pwm, struct pwm_capture *result, unsigned long timeout); + + size_t sizeof_wfhw; + int (*round_waveform_tohw)(struct pwm_chip *chip, struct pwm_device *pwm, + const struct pwm_waveform *wf, void *wfhw); + int (*round_waveform_fromhw)(struct pwm_chip *chip, struct pwm_device *pwm, + const void *wfhw, struct pwm_waveform *wf); + int (*read_waveform)(struct pwm_chip *chip, struct pwm_device *pwm, + void *wfhw); + int (*write_waveform)(struct pwm_chip *chip, struct pwm_device *pwm, + const void *wfhw); + int (*apply)(struct pwm_chip *chip, struct pwm_device *pwm, const struct pwm_state *state); int (*get_state)(struct pwm_chip *chip, struct pwm_device *pwm, |