+static int
+bxt_setup_backlight(struct intel_connector *connector, enum pipe unused)
+{
+ struct drm_device *dev = connector->base.dev;
+ struct drm_i915_private *dev_priv = dev->dev_private;
+ struct intel_panel *panel = &connector->panel;
+ u32 pwm_ctl, val;
+
+ /*
+ * For BXT hard coding the Backlight controller to 0.
+ * TODO : Read the controller value from VBT and generalize
+ */
+ panel->backlight.controller = 0;
+
+ pwm_ctl = I915_READ(BXT_BLC_PWM_CTL(panel->backlight.controller));
+
+ /* Keeping the check if controller 1 is to be programmed.
+ * This will come into affect once the VBT parsing
+ * is fixed for controller selection, and controller 1 is used
+ * for a prticular display configuration.
+ */
+ if (panel->backlight.controller == 1) {
+ val = I915_READ(UTIL_PIN_CTL);
+ panel->backlight.util_pin_active_low =
+ val & UTIL_PIN_POLARITY;
+ }
+
+ panel->backlight.active_low_pwm = pwm_ctl & BXT_BLC_PWM_POLARITY;
+ panel->backlight.max =
+ I915_READ(BXT_BLC_PWM_FREQ(panel->backlight.controller));
+
+ if (!panel->backlight.max)
+ panel->backlight.max = get_backlight_max_vbt(connector);
+
+ if (!panel->backlight.max)
+ return -ENODEV;
+
+ val = bxt_get_backlight(connector);
+ panel->backlight.level = intel_panel_compute_brightness(connector, val);
+
+ panel->backlight.enabled = (pwm_ctl & BXT_BLC_PWM_ENABLE) &&
+ panel->backlight.level != 0;
+
+ return 0;
+}
+
+static int pwm_setup_backlight(struct intel_connector *connector,
+ enum pipe pipe)
+{
+ struct drm_device *dev = connector->base.dev;
+ struct intel_panel *panel = &connector->panel;
+ int retval;
+
+ /* Get the PWM chip for backlight control */
+ panel->backlight.pwm = pwm_get(dev->dev, "pwm_backlight");
+ if (IS_ERR(panel->backlight.pwm)) {
+ DRM_ERROR("Failed to own the pwm chip\n");
+ panel->backlight.pwm = NULL;
+ return -ENODEV;
+ }
+
+ retval = pwm_config(panel->backlight.pwm, CRC_PMIC_PWM_PERIOD_NS,
+ CRC_PMIC_PWM_PERIOD_NS);
+ if (retval < 0) {
+ DRM_ERROR("Failed to configure the pwm chip\n");
+ pwm_put(panel->backlight.pwm);
+ panel->backlight.pwm = NULL;
+ 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);
+ panel->backlight.enabled = panel->backlight.level != 0;
+
+ return 0;
+}
+