From 832ce36f44a2c5dd3cb6be6dfb9003715f8dca2a Mon Sep 17 00:00:00 2001 From: Song Chen Date: Fri, 18 Mar 2022 17:57:12 +0800 Subject: [PATCH] staging: greybus: introduce pwm_ops::apply Introduce newer .apply function in pwm_ops to replace legacy operations including enable, disable, config and set_polarity. This guarantees atomic changes of the pwm controller configuration. Reviewed-by: Alex Elder Signed-off-by: Song Chen Link: https://lore.kernel.org/r/1647597432-27586-1-git-send-email-chensong_2000@189.cn Signed-off-by: Greg Kroah-Hartman --- drivers/staging/greybus/pwm.c | 64 +++++++++++++++++++++++++++---------------- 1 file changed, 40 insertions(+), 24 deletions(-) diff --git a/drivers/staging/greybus/pwm.c b/drivers/staging/greybus/pwm.c index 891a6a6..ad20ec2 100644 --- a/drivers/staging/greybus/pwm.c +++ b/drivers/staging/greybus/pwm.c @@ -204,43 +204,59 @@ 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; + u64 period = state->period; + u64 duty_cycle = state->duty_cycle; struct gb_pwm_chip *pwmc = pwm_chip_to_gb_pwm_chip(chip); - return gb_pwm_config_operation(pwmc, pwm->hwpwm, duty_ns, period_ns); -}; + /* 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_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); + if (!state->enabled) { + if (enabled) + gb_pwm_disable_operation(pwmc, pwm->hwpwm); + return 0; + } - return gb_pwm_set_polarity_operation(pwmc, pwm->hwpwm, polarity); -}; + /* + * Set period and duty cycle + * + * PWM privodes 64-bit period and duty_cycle, but greybus only accepts + * 32-bit, so their values have to be limited to U32_MAX. + */ + if (period > U32_MAX) + period = U32_MAX; -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 (duty_cycle > period) + duty_cycle = period; - return gb_pwm_enable_operation(pwmc, pwm->hwpwm); -}; + err = gb_pwm_config_operation(pwmc, pwm->hwpwm, duty_cycle, 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, }; -- 2.7.4