@@ -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");
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 <alexander.stein@ew.tq-group.com> --- drivers/hwmon/pwm-fan.c | 43 ++++++++++++++++++++++++++++++++--------- 1 file changed, 34 insertions(+), 9 deletions(-)