On Fri, Jul 17, 2020 at 03:37:48PM +0200, Hans de Goede wrote:
> Replace the enable, disable and config pwm_ops with an apply op,
> to support the new atomic PWM API.
I didn't notice any visible issue, so
Reviewed-by: Andy Shevchenko <andriy.shevchenko@xxxxxxxxxxxxxxx>
Perhaps you may consider reusing existing _enable() / _disable(), but I don't
see if there will be nice improvement (maybe if in on of the previous patches
you also add an error handling to them first).
> Signed-off-by: Hans de Goede <hdegoede@xxxxxxxxxx>
> ---
> Changes in v3:
> - Keep crc_pwm_calc_clk_div() helper to avoid needless churn
> ---
> drivers/pwm/pwm-crc.c | 89 ++++++++++++++++++++++++++-----------------
> 1 file changed, 53 insertions(+), 36 deletions(-)
>
> diff --git a/drivers/pwm/pwm-crc.c b/drivers/pwm/pwm-crc.c
> index b72008c9b072..8a7f4707279c 100644
> --- a/drivers/pwm/pwm-crc.c
> +++ b/drivers/pwm/pwm-crc.c
> @@ -51,59 +51,76 @@ static int crc_pwm_calc_clk_div(int period_ns)
> return clk_div;
> }
>
> -static int crc_pwm_enable(struct pwm_chip *c, struct pwm_device *pwm)
> +static int crc_pwm_apply(struct pwm_chip *chip, struct pwm_device *pwm,
> + const struct pwm_state *state)
> {
> - struct crystalcove_pwm *crc_pwm = to_crc_pwm(c);
> - int div = crc_pwm_calc_clk_div(pwm_get_period(pwm));
> -
> - regmap_write(crc_pwm->regmap, PWM0_CLK_DIV, div | PWM_OUTPUT_ENABLE);
> - regmap_write(crc_pwm->regmap, BACKLIGHT_EN, 1);
> -
> - return 0;
> -}
> -
> -static void crc_pwm_disable(struct pwm_chip *c, struct pwm_device *pwm)
> -{
> - struct crystalcove_pwm *crc_pwm = to_crc_pwm(c);
> - int div = crc_pwm_calc_clk_div(pwm_get_period(pwm));
> -
> - regmap_write(crc_pwm->regmap, BACKLIGHT_EN, 0);
> - regmap_write(crc_pwm->regmap, PWM0_CLK_DIV, div);
> -}
> -
> -static int crc_pwm_config(struct pwm_chip *c, struct pwm_device *pwm,
> - int duty_ns, int period_ns)
> -{
> - struct crystalcove_pwm *crc_pwm = to_crc_pwm(c);
> + struct crystalcove_pwm *crc_pwm = to_crc_pwm(chip);
> struct device *dev = crc_pwm->chip.dev;
> - int level;
> + int err;
>
> - if (period_ns > PWM_MAX_PERIOD_NS) {
> + if (state->period > PWM_MAX_PERIOD_NS) {
> dev_err(dev, "un-supported period_ns\n");
> return -EINVAL;
> }
>
> - if (pwm_get_period(pwm) != period_ns) {
> - int clk_div = crc_pwm_calc_clk_div(period_ns);
> + if (state->polarity != PWM_POLARITY_NORMAL)
> + return -EOPNOTSUPP;
> +
> + if (pwm_is_enabled(pwm) && !state->enabled) {
> + err = regmap_write(crc_pwm->regmap, BACKLIGHT_EN, 0);
> + if (err) {
> + dev_err(dev, "Error writing BACKLIGHT_EN %d\n", err);
> + return err;
> + }
> + }
> +
> + if (pwm_get_duty_cycle(pwm) != state->duty_cycle ||
> + pwm_get_period(pwm) != state->period) {
> + int level = state->duty_cycle * PWM_MAX_LEVEL / state->period;
>
> + err = regmap_write(crc_pwm->regmap, PWM0_DUTY_CYCLE, level);
> + if (err) {
> + dev_err(dev, "Error writing PWM0_DUTY_CYCLE %d\n", err);
> + return err;
> + }
> + }
> +
> + if (pwm_is_enabled(pwm) && state->enabled &&
> + pwm_get_period(pwm) != state->period) {
> /* changing the clk divisor, clear PWM_OUTPUT_ENABLE first */
> - regmap_write(crc_pwm->regmap, PWM0_CLK_DIV, 0);
> + err = regmap_write(crc_pwm->regmap, PWM0_CLK_DIV, 0);
> + if (err) {
> + dev_err(dev, "Error writing PWM0_CLK_DIV %d\n", err);
> + return err;
> + }
> + }
>
> - regmap_write(crc_pwm->regmap, PWM0_CLK_DIV,
> - clk_div | PWM_OUTPUT_ENABLE);
> + if (pwm_get_period(pwm) != state->period ||
> + pwm_is_enabled(pwm) != state->enabled) {
> + int clk_div = crc_pwm_calc_clk_div(state->period);
> + int pwm_output_enable = state->enabled ? PWM_OUTPUT_ENABLE : 0;
> +
> + err = regmap_write(crc_pwm->regmap, PWM0_CLK_DIV,
> + clk_div | pwm_output_enable);
> + if (err) {
> + dev_err(dev, "Error writing PWM0_CLK_DIV %d\n", err);
> + return err;
> + }
> }
>
> - /* change the pwm duty cycle */
> - level = duty_ns * PWM_MAX_LEVEL / period_ns;
> - regmap_write(crc_pwm->regmap, PWM0_DUTY_CYCLE, level);
> + if (!pwm_is_enabled(pwm) && state->enabled) {
> + err = regmap_write(crc_pwm->regmap, BACKLIGHT_EN, 1);
> + if (err) {
> + dev_err(dev, "Error writing BACKLIGHT_EN %d\n", err);
> + return err;
> + }
> + }
>
> return 0;
> }
>
> static const struct pwm_ops crc_pwm_ops = {
> - .config = crc_pwm_config,
> - .enable = crc_pwm_enable,
> - .disable = crc_pwm_disable,
> + .apply = crc_pwm_apply,
> };
>
> static int crystalcove_pwm_probe(struct platform_device *pdev)
> --
> 2.26.2
>
--
With Best Regards,
Andy Shevchenko
