diff --git a/drivers/video/backlight/pwm_bl.c b/drivers/video/backlight/pwm_bl.c index 678b27063198..f9ef0673a083 100644 --- a/drivers/video/backlight/pwm_bl.c +++ b/drivers/video/backlight/pwm_bl.c @@ -562,7 +562,30 @@ static int pwm_backlight_probe(struct platform_device *pdev) goto err_alloc; } - if (!data->levels) { + if (data->levels) { + /* + * For the DT case, only when brightness levels is defined + * data->levels is filled. For the non-DT case, data->levels + * can come from platform data, however is not usual. + */ + for (i = 0; i <= data->max_brightness; i++) { + if (data->levels[i] > pb->scale) + pb->scale = data->levels[i]; + + pb->levels = data->levels; + } + } else if (!data->max_brightness) { + /* + * If no brightness levels are provided and max_brightness is + * not set, use the default brightness table. For the DT case, + * max_brightness is set to 0 when brightness levels is not + * specified. For the non-DT case, max_brightness is usually + * set to some value. + */ + + /* Get the PWM period (in nanoseconds) */ + pwm_get_state(pb->pwm, &state); + ret = pwm_backlight_brightness_default(&pdev->dev, data, state.period); if (ret < 0) { @@ -570,13 +593,19 @@ static int pwm_backlight_probe(struct platform_device *pdev) "failed to setup default brightness table\n"); goto err_alloc; } - } - for (i = 0; i <= data->max_brightness; i++) { - if (data->levels[i] > pb->scale) - pb->scale = data->levels[i]; + for (i = 0; i <= data->max_brightness; i++) { + if (data->levels[i] > pb->scale) + pb->scale = data->levels[i]; - pb->levels = data->levels; + pb->levels = data->levels; + } + } else { + /* + * That only happens for the non-DT case, where platform data + * sets the max_brightness value. + */ + pb->scale = data->max_brightness; } pb->lth_brightness = data->lth_brightness * (state.period / pb->scale);