Re: [PATCH v2] staging: greybus: introduce pwm_ops::apply

Greg KH
2022-02-21T17:06:59Z

On Fri, Feb 11, 2022 at 08:02:27PM +0800, Song Chen wrote:
> Introduce apply in pwm_ops to replace legacy operations,
> like enable, disable, config and set_polarity.
>
> Signed-off-by: Song Chen <chensong_2000@189.cn>
>
> ---
> V2:
> 1, define duty_cycle and period as u64 in gb_pwm_config_operation.
> 2, define duty and period as u64 in gb_pwm_config_request.
> 3, disable before configuring duty and period if the eventual goal
> is a disabled state.
> ---
> drivers/staging/greybus/pwm.c | 61 ++++++++++++-----------
> include/linux/greybus/greybus_protocols.h | 4 +-
> 2 files changed, 34 insertions(+), 31 deletions(-)
>
> diff --git a/drivers/staging/greybus/pwm.c b/drivers/staging/greybus/pwm.c
> index 891a6a672378..03c69db5b9be 100644
> --- a/drivers/staging/greybus/pwm.c
> +++ b/drivers/staging/greybus/pwm.c
> @@ -89,7 +89,7 @@ static int gb_pwm_deactivate_operation(struct gb_pwm_chip *pwmc,
> }
>
> static int gb_pwm_config_operation(struct gb_pwm_chip *pwmc,
> - u8 which, u32 duty, u32 period)
> + u8 which, u64 duty, u64 period)
> {
> struct gb_pwm_config_request request;
> struct gbphy_device *gbphy_dev;
> @@ -99,8 +99,8 @@ static int gb_pwm_config_operation(struct gb_pwm_chip *pwmc,
> return -EINVAL;
>
> request.which = which;
> - request.duty = cpu_to_le32(duty);
> - request.period = cpu_to_le32(period);
> + request.duty = duty;
> + request.period = period;
>
> gbphy_dev = to_gbphy_dev(pwmc->chip.dev);
> ret = gbphy_runtime_get_sync(gbphy_dev);
> @@ -204,43 +204,46 @@ static void gb_pwm_free(struct pwm_chip *chip, struct pwm_device *pwm)
> gb_pwm_deactivate_operation(pwmc, pwm->hwpwm);
> }
>
> -static int gb_pwm_config(struct pwm_chip *chip, struct pwm_device *pwm,
> - int duty_ns, int period_ns)
> +static int gb_pwm_apply(struct pwm_chip *chip, struct pwm_device *pwm,
> + const struct pwm_state *state)
> {
> + int err;
> + bool enabled = pwm->state.enabled;
> struct gb_pwm_chip *pwmc = pwm_chip_to_gb_pwm_chip(chip);
>
> - return gb_pwm_config_operation(pwmc, pwm->hwpwm, duty_ns, period_ns);
> -};
> -
> -static int gb_pwm_set_polarity(struct pwm_chip *chip, struct pwm_device *pwm,
> - enum pwm_polarity polarity)
> -{
> - struct gb_pwm_chip *pwmc = pwm_chip_to_gb_pwm_chip(chip);
> -
> - return gb_pwm_set_polarity_operation(pwmc, pwm->hwpwm, polarity);
> -};
> + /* set polarity */
> + if (state->polarity != pwm->state.polarity) {
> + if (enabled) {
> + gb_pwm_disable_operation(pwmc, pwm->hwpwm);
> + enabled = false;
> + }
> + err = gb_pwm_set_polarity_operation(pwmc, pwm->hwpwm, state->polarity);
> + if (err)
> + return err;
> + }
>
> -static int gb_pwm_enable(struct pwm_chip *chip, struct pwm_device *pwm)
> -{
> - struct gb_pwm_chip *pwmc = pwm_chip_to_gb_pwm_chip(chip);
> + if (!state->enabled) {
> + if (enabled)
> + gb_pwm_disable_operation(pwmc, pwm->hwpwm);
> + return 0;
> + }
>
> - return gb_pwm_enable_operation(pwmc, pwm->hwpwm);
> -};
> + /* set period and duty cycle*/
> + err = gb_pwm_config_operation(pwmc, pwm->hwpwm, state->duty_cycle, state->period);
> + if (err)
> + return err;
>
> -static void gb_pwm_disable(struct pwm_chip *chip, struct pwm_device *pwm)
> -{
> - struct gb_pwm_chip *pwmc = pwm_chip_to_gb_pwm_chip(chip);
> + /* enable/disable */
> + if (!enabled)
> + return gb_pwm_enable_operation(pwmc, pwm->hwpwm);
>
> - gb_pwm_disable_operation(pwmc, pwm->hwpwm);
> -};
> + return 0;
> +}
>
> static const struct pwm_ops gb_pwm_ops = {
> .request = gb_pwm_request,
> .free = gb_pwm_free,
> - .config = gb_pwm_config,
> - .set_polarity = gb_pwm_set_polarity,
> - .enable = gb_pwm_enable,
> - .disable = gb_pwm_disable,
> + .apply = gb_pwm_apply,
> .owner = THIS_MODULE,
> };
>
> diff --git a/include/linux/greybus/greybus_protocols.h b/include/linux/greybus/greybus_protocols.h
> index aeb8f9243545..81a6f16de098 100644
> --- a/include/linux/greybus/greybus_protocols.h
> +++ b/include/linux/greybus/greybus_protocols.h
> @@ -812,8 +812,8 @@ struct gb_pwm_deactivate_request {
>
> struct gb_pwm_config_request {
> __u8 which;
> - __le32 duty;
> - __le32 period;
> + __u64 duty;
> + __u64 period;
> } __packed;

Did you just change a greybus protocol message that is sent over the
wire? Why? And why drop the endian marking of it?

Are you sure this is ok?

thanks,

greg k-h