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path: root/drivers/video/pwm_backlight.c
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Diffstat (limited to 'drivers/video/pwm_backlight.c')
-rw-r--r--drivers/video/pwm_backlight.c20
1 files changed, 14 insertions, 6 deletions
diff --git a/drivers/video/pwm_backlight.c b/drivers/video/pwm_backlight.c
index 9e32bc47cf..4c86215bd7 100644
--- a/drivers/video/pwm_backlight.c
+++ b/drivers/video/pwm_backlight.c
@@ -62,10 +62,17 @@ static int set_pwm(struct pwm_backlight_priv *priv)
uint duty_cycle;
int ret;
- duty_cycle = priv->period_ns * (priv->cur_level - priv->min_level) /
- (priv->max_level - priv->min_level);
- ret = pwm_set_config(priv->pwm, priv->channel, priv->period_ns,
- duty_cycle);
+ if (priv->period_ns) {
+ duty_cycle = priv->period_ns * (priv->cur_level - priv->min_level) /
+ (priv->max_level - priv->min_level);
+ ret = pwm_set_config(priv->pwm, priv->channel, priv->period_ns,
+ duty_cycle);
+ } else {
+ /* PWM driver will internally scale these like the above. */
+ ret = pwm_set_config(priv->pwm, priv->channel,
+ priv->max_level - priv->min_level,
+ priv->cur_level - priv->min_level);
+ }
if (ret)
return log_ret(ret);
@@ -213,10 +220,11 @@ static int pwm_backlight_of_to_plat(struct udevice *dev)
log_debug("Cannot get PWM: ret=%d\n", ret);
return log_ret(ret);
}
- if (args.args_count < 2)
+ if (args.args_count < 1)
return log_msg_ret("Not enough arguments to pwm\n", -EINVAL);
priv->channel = args.args[0];
- priv->period_ns = args.args[1];
+ if (args.args_count > 1)
+ priv->period_ns = args.args[1];
if (args.args_count > 2)
priv->polarity = args.args[2];