drm/i915: panel: Use intel_panel_compute_brightness() from pwm_setup_backlight()

Use intel_panel_compute_brightness() from pwm_setup_backlight() so that
we correctly take i915_modparams.invert_brightness and/or
QUIRK_INVERT_BRIGHTNESS into account when setting + getting the initial
brightness value.

Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Reviewed-by: Jani Nikula <jani.nikula@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200221172927.510027-1-hdegoede@redhat.com

diff --git a/drivers/gpu/drm/i915/display/intel_panel.c b/drivers/gpu/drm/i915/display/intel_panel.c
index 5aead622019ccfd26aa19cf3ef0ca0c0a18ef158..276f438708026e1cf0846ffe9eb1e9adaa28a38d 100644 (file)
--- a/drivers/gpu/drm/i915/display/intel_panel.c
+++ b/drivers/gpu/drm/i915/display/intel_panel.c
@@ -1882,6 +1882,7 @@ static int pwm_setup_backlight(struct intel_connector *connector,
        struct drm_i915_private *dev_priv = to_i915(dev);
        struct intel_panel *panel = &connector->panel;
        const char *desc;
+       u32 level, ns;
        int retval;
 
        /* Get the right PWM chip for DSI backlight according to VBT */
@@ -1906,8 +1907,12 @@ static int pwm_setup_backlight(struct intel_connector *connector,
         */
        pwm_apply_args(panel->backlight.pwm);
 
-       retval = pwm_config(panel->backlight.pwm, CRC_PMIC_PWM_PERIOD_NS,
-                           CRC_PMIC_PWM_PERIOD_NS);
+       panel->backlight.min = 0; /* 0% */
+       panel->backlight.max = 100; /* 100% */
+       level = intel_panel_compute_brightness(connector, 100);
+       ns = DIV_ROUND_UP(level * CRC_PMIC_PWM_PERIOD_NS, 100);
+
+       retval = pwm_config(panel->backlight.pwm, ns, CRC_PMIC_PWM_PERIOD_NS);
        if (retval < 0) {
                drm_err(&dev_priv->drm, "Failed to configure the pwm chip\n");
                pwm_put(panel->backlight.pwm);
@@ -1915,11 +1920,10 @@ static int pwm_setup_backlight(struct intel_connector *connector,
                return retval;
        }
 
-       panel->backlight.min = 0; /* 0% */
-       panel->backlight.max = 100; /* 100% */
-       panel->backlight.level = DIV_ROUND_UP(
-                                pwm_get_duty_cycle(panel->backlight.pwm) * 100,
-                                CRC_PMIC_PWM_PERIOD_NS);
+       level = DIV_ROUND_UP(pwm_get_duty_cycle(panel->backlight.pwm) * 100,
+                            CRC_PMIC_PWM_PERIOD_NS);
+       panel->backlight.level =
+               intel_panel_compute_brightness(connector, level);
        panel->backlight.enabled = panel->backlight.level != 0;
 
        drm_info(&dev_priv->drm, "Using %s PWM for LCD backlight control\n",