From b77f0c7680a4df2a550be5e0158204de1aa3a3ce Mon Sep 17 00:00:00 2001 From: Alexander Stein Date: Wed, 14 Sep 2022 17:31:34 +0200 Subject: hwmon: (pwm-fan) Simplify enable/disable check Instead of comparing the current to the new pwm duty to decide whether to enable the PWM, use a dedicated flag. Also apply the new PWM duty in any case. This is a preparation to enable/disable the regulator dynamically. Signed-off-by: Alexander Stein Link: https://lore.kernel.org/r/20220914153137.613982-3-alexander.stein@ew.tq-group.com Signed-off-by: Guenter Roeck --- drivers/hwmon/pwm-fan.c | 43 ++++++++++++++++++++++++++++++++++--------- 1 file changed, 34 insertions(+), 9 deletions(-) (limited to 'drivers/hwmon/pwm-fan.c') diff --git a/drivers/hwmon/pwm-fan.c b/drivers/hwmon/pwm-fan.c index c8a7926d39e7..01412c71deb3 100644 --- a/drivers/hwmon/pwm-fan.c +++ b/drivers/hwmon/pwm-fan.c @@ -29,10 +29,13 @@ struct pwm_fan_tach { }; struct pwm_fan_ctx { + struct device *dev; + struct mutex lock; struct pwm_device *pwm; struct pwm_state pwm_state; struct regulator *reg_en; + bool enabled; int tach_count; struct pwm_fan_tach *tachs; @@ -85,13 +88,19 @@ static void sample_timer(struct timer_list *t) static int pwm_fan_power_on(struct pwm_fan_ctx *ctx) { struct pwm_state *state = &ctx->pwm_state; - unsigned long period; int ret; - period = state->period; - state->duty_cycle = DIV_ROUND_UP(ctx->pwm_value * (period - 1), MAX_PWM); + if (ctx->enabled) + return 0; + state->enabled = true; ret = pwm_apply_state(ctx->pwm, state); + if (ret) { + dev_err(ctx->dev, "failed to enable PWM\n"); + return ret; + } + + ctx->enabled = true; return ret; } @@ -99,27 +108,42 @@ static int pwm_fan_power_on(struct pwm_fan_ctx *ctx) static int pwm_fan_power_off(struct pwm_fan_ctx *ctx) { struct pwm_state *state = &ctx->pwm_state; + int ret; + + if (!ctx->enabled) + return 0; state->enabled = false; state->duty_cycle = 0; - pwm_apply_state(ctx->pwm, state); + ret = pwm_apply_state(ctx->pwm, state); + if (ret) { + dev_err(ctx->dev, "failed to disable PWM\n"); + return ret; + } + + ctx->enabled = false; return 0; } static int __set_pwm(struct pwm_fan_ctx *ctx, unsigned long pwm) { + struct pwm_state *state = &ctx->pwm_state; + unsigned long period; int ret = 0; mutex_lock(&ctx->lock); - if (ctx->pwm_value == pwm) - goto exit_set_pwm_err; - if (pwm > 0) + if (pwm > 0) { + period = state->period; + state->duty_cycle = DIV_ROUND_UP(pwm * (period - 1), MAX_PWM); + ret = pwm_apply_state(ctx->pwm, state); + if (ret) + goto exit_set_pwm_err; ret = pwm_fan_power_on(ctx); - else + } else { ret = pwm_fan_power_off(ctx); - + } if (!ret) ctx->pwm_value = pwm; @@ -326,6 +350,7 @@ static int pwm_fan_probe(struct platform_device *pdev) mutex_init(&ctx->lock); + ctx->dev = &pdev->dev; ctx->pwm = devm_pwm_get(dev, NULL); if (IS_ERR(ctx->pwm)) return dev_err_probe(dev, PTR_ERR(ctx->pwm), "Could not get PWM\n"); -- cgit v1.2.3