1 files changed, 185 insertions, 67 deletions

diff --git a/drivers/gpu/drm/i915/intel_panel.c b/drivers/gpu/drm/i915/intel_panel.c
index cb50c527401f..96c2cbd81869 100644
--- a/drivers/gpu/drm/i915/intel_panel.c
+++ b/drivers/gpu/drm/i915/intel_panel.c
@@ -561,15 +561,18 @@ static u32 intel_panel_get_backlight(struct intel_connector *connector)
 	return val;
 }
 
-static void lpt_set_backlight(struct intel_connector *connector, u32 level)
+static void lpt_set_backlight(const struct drm_connector_state *conn_state, u32 level)
 {
+	struct intel_connector *connector = to_intel_connector(conn_state->connector);
 	struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
+
 	u32 val = I915_READ(BLC_PWM_PCH_CTL2) & ~BACKLIGHT_DUTY_CYCLE_MASK;
 	I915_WRITE(BLC_PWM_PCH_CTL2, val | level);
 }
 
-static void pch_set_backlight(struct intel_connector *connector, u32 level)
+static void pch_set_backlight(const struct drm_connector_state *conn_state, u32 level)
 {
+	struct intel_connector *connector = to_intel_connector(conn_state->connector);
 	struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
 	u32 tmp;
 
@@ -577,8 +580,9 @@ static void pch_set_backlight(struct intel_connector *connector, u32 level)
 	I915_WRITE(BLC_PWM_CPU_CTL, tmp | level);
 }
 
-static void i9xx_set_backlight(struct intel_connector *connector, u32 level)
+static void i9xx_set_backlight(const struct drm_connector_state *conn_state, u32 level)
 {
+	struct intel_connector *connector = to_intel_connector(conn_state->connector);
 	struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
 	struct intel_panel *panel = &connector->panel;
 	u32 tmp, mask;
@@ -604,50 +608,51 @@ static void i9xx_set_backlight(struct intel_connector *connector, u32 level)
 	I915_WRITE(BLC_PWM_CTL, tmp | level);
 }
 
-static void vlv_set_backlight(struct intel_connector *connector, u32 level)
+static void vlv_set_backlight(const struct drm_connector_state *conn_state, u32 level)
 {
+	struct intel_connector *connector = to_intel_connector(conn_state->connector);
 	struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
-	enum pipe pipe = intel_get_pipe_from_connector(connector);
+	enum pipe pipe = to_intel_crtc(conn_state->crtc)->pipe;
 	u32 tmp;
 
-	if (WARN_ON(pipe != PIPE_A && pipe != PIPE_B))
-		return;
-
 	tmp = I915_READ(VLV_BLC_PWM_CTL(pipe)) & ~BACKLIGHT_DUTY_CYCLE_MASK;
 	I915_WRITE(VLV_BLC_PWM_CTL(pipe), tmp | level);
 }
 
-static void bxt_set_backlight(struct intel_connector *connector, u32 level)
+static void bxt_set_backlight(const struct drm_connector_state *conn_state, u32 level)
 {
+	struct intel_connector *connector = to_intel_connector(conn_state->connector);
 	struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
 	struct intel_panel *panel = &connector->panel;
 
 	I915_WRITE(BXT_BLC_PWM_DUTY(panel->backlight.controller), level);
 }
 
-static void pwm_set_backlight(struct intel_connector *connector, u32 level)
+static void pwm_set_backlight(const struct drm_connector_state *conn_state, u32 level)
 {
-	struct intel_panel *panel = &connector->panel;
+	struct intel_panel *panel = &to_intel_connector(conn_state->connector)->panel;
 	int duty_ns = DIV_ROUND_UP(level * CRC_PMIC_PWM_PERIOD_NS, 100);
 
 	pwm_config(panel->backlight.pwm, duty_ns, CRC_PMIC_PWM_PERIOD_NS);
 }
 
 static void
-intel_panel_actually_set_backlight(struct intel_connector *connector, u32 level)
+intel_panel_actually_set_backlight(const struct drm_connector_state *conn_state, u32 level)
 {
+	struct intel_connector *connector = to_intel_connector(conn_state->connector);
 	struct intel_panel *panel = &connector->panel;
 
 	DRM_DEBUG_DRIVER("set backlight PWM = %d\n", level);
 
 	level = intel_panel_compute_brightness(connector, level);
-	panel->backlight.set(connector, level);
+	panel->backlight.set(conn_state, level);
 }
 
 /* set backlight brightness to level in range [0..max], scaling wrt hw min */
-static void intel_panel_set_backlight(struct intel_connector *connector,
+static void intel_panel_set_backlight(const struct drm_connector_state *conn_state,
 				      u32 user_level, u32 user_max)
 {
+	struct intel_connector *connector = to_intel_connector(conn_state->connector);
 	struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
 	struct intel_panel *panel = &connector->panel;
 	u32 hw_level;
@@ -663,7 +668,7 @@ static void intel_panel_set_backlight(struct intel_connector *connector,
 	panel->backlight.level = hw_level;
 
 	if (panel->backlight.enabled)
-		intel_panel_actually_set_backlight(connector, hw_level);
+		intel_panel_actually_set_backlight(conn_state, hw_level);
 
 	mutex_unlock(&dev_priv->backlight_lock);
 }
@@ -671,21 +676,21 @@ static void intel_panel_set_backlight(struct intel_connector *connector,
 /* set backlight brightness to level in range [0..max], assuming hw min is
  * respected.
  */
-void intel_panel_set_backlight_acpi(struct intel_connector *connector,
+void intel_panel_set_backlight_acpi(const struct drm_connector_state *conn_state,
 				    u32 user_level, u32 user_max)
 {
+	struct intel_connector *connector = to_intel_connector(conn_state->connector);
 	struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
 	struct intel_panel *panel = &connector->panel;
-	enum pipe pipe = intel_get_pipe_from_connector(connector);
 	u32 hw_level;
 
 	/*
-	 * INVALID_PIPE may occur during driver init because
+	 * Lack of crtc may occur during driver init because
 	 * connection_mutex isn't held across the entire backlight
 	 * setup + modeset readout, and the BIOS can issue the
 	 * requests at any time.
 	 */
-	if (!panel->backlight.present || pipe == INVALID_PIPE)
+	if (!panel->backlight.present || !conn_state->crtc)
 		return;
 
 	mutex_lock(&dev_priv->backlight_lock);
@@ -702,17 +707,18 @@ void intel_panel_set_backlight_acpi(struct intel_connector *connector,
 					 panel->backlight.device->props.max_brightness);
 
 	if (panel->backlight.enabled)
-		intel_panel_actually_set_backlight(connector, hw_level);
+		intel_panel_actually_set_backlight(conn_state, hw_level);
 
 	mutex_unlock(&dev_priv->backlight_lock);
 }
 
-static void lpt_disable_backlight(struct intel_connector *connector)
+static void lpt_disable_backlight(const struct drm_connector_state *old_conn_state)
 {
+	struct intel_connector *connector = to_intel_connector(old_conn_state->connector);
 	struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
 	u32 tmp;
 
-	intel_panel_actually_set_backlight(connector, 0);
+	intel_panel_actually_set_backlight(old_conn_state, 0);
 
 	/*
 	 * Although we don't support or enable CPU PWM with LPT/SPT based
@@ -732,12 +738,13 @@ static void lpt_disable_backlight(struct intel_connector *connector)
 	I915_WRITE(BLC_PWM_PCH_CTL1, tmp & ~BLM_PCH_PWM_ENABLE);
 }
 
-static void pch_disable_backlight(struct intel_connector *connector)
+static void pch_disable_backlight(const struct drm_connector_state *old_conn_state)
 {
+	struct intel_connector *connector = to_intel_connector(old_conn_state->connector);
 	struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
 	u32 tmp;
 
-	intel_panel_actually_set_backlight(connector, 0);
+	intel_panel_actually_set_backlight(old_conn_state, 0);
 
 	tmp = I915_READ(BLC_PWM_CPU_CTL2);
 	I915_WRITE(BLC_PWM_CPU_CTL2, tmp & ~BLM_PWM_ENABLE);
@@ -746,44 +753,43 @@ static void pch_disable_backlight(struct intel_connector *connector)
 	I915_WRITE(BLC_PWM_PCH_CTL1, tmp & ~BLM_PCH_PWM_ENABLE);
 }
 
-static void i9xx_disable_backlight(struct intel_connector *connector)
+static void i9xx_disable_backlight(const struct drm_connector_state *old_conn_state)
 {
-	intel_panel_actually_set_backlight(connector, 0);
+	intel_panel_actually_set_backlight(old_conn_state, 0);
 }
 
-static void i965_disable_backlight(struct intel_connector *connector)
+static void i965_disable_backlight(const struct drm_connector_state *old_conn_state)
 {
-	struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
+	struct drm_i915_private *dev_priv = to_i915(old_conn_state->connector->dev);
 	u32 tmp;
 
-	intel_panel_actually_set_backlight(connector, 0);
+	intel_panel_actually_set_backlight(old_conn_state, 0);
 
 	tmp = I915_READ(BLC_PWM_CTL2);
 	I915_WRITE(BLC_PWM_CTL2, tmp & ~BLM_PWM_ENABLE);
 }
 
-static void vlv_disable_backlight(struct intel_connector *connector)
+static void vlv_disable_backlight(const struct drm_connector_state *old_conn_state)
 {
+	struct intel_connector *connector = to_intel_connector(old_conn_state->connector);
 	struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
-	enum pipe pipe = intel_get_pipe_from_connector(connector);
+	enum pipe pipe = to_intel_crtc(old_conn_state->crtc)->pipe;
 	u32 tmp;
 
-	if (WARN_ON(pipe != PIPE_A && pipe != PIPE_B))
-		return;
-
-	intel_panel_actually_set_backlight(connector, 0);
+	intel_panel_actually_set_backlight(old_conn_state, 0);
 
 	tmp = I915_READ(VLV_BLC_PWM_CTL2(pipe));
 	I915_WRITE(VLV_BLC_PWM_CTL2(pipe), tmp & ~BLM_PWM_ENABLE);
 }
 
-static void bxt_disable_backlight(struct intel_connector *connector)
+static void bxt_disable_backlight(const struct drm_connector_state *old_conn_state)
 {
+	struct intel_connector *connector = to_intel_connector(old_conn_state->connector);
 	struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
 	struct intel_panel *panel = &connector->panel;
 	u32 tmp, val;
 
-	intel_panel_actually_set_backlight(connector, 0);
+	intel_panel_actually_set_backlight(old_conn_state, 0);
 
 	tmp = I915_READ(BXT_BLC_PWM_CTL(panel->backlight.controller));
 	I915_WRITE(BXT_BLC_PWM_CTL(panel->backlight.controller),
@@ -796,8 +802,23 @@ static void bxt_disable_backlight(struct intel_connector *connector)
 	}
 }
 
-static void pwm_disable_backlight(struct intel_connector *connector)
+static void cnp_disable_backlight(const struct drm_connector_state *old_conn_state)
 {
+	struct intel_connector *connector = to_intel_connector(old_conn_state->connector);
+	struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
+	struct intel_panel *panel = &connector->panel;
+	u32 tmp;
+
+	intel_panel_actually_set_backlight(old_conn_state, 0);
+
+	tmp = I915_READ(BXT_BLC_PWM_CTL(panel->backlight.controller));
+	I915_WRITE(BXT_BLC_PWM_CTL(panel->backlight.controller),
+		   tmp & ~BXT_BLC_PWM_ENABLE);
+}
+
+static void pwm_disable_backlight(const struct drm_connector_state *old_conn_state)
+{
+	struct intel_connector *connector = to_intel_connector(old_conn_state->connector);
 	struct intel_panel *panel = &connector->panel;
 
 	/* Disable the backlight */
@@ -806,8 +827,9 @@ static void pwm_disable_backlight(struct intel_connector *connector)
 	pwm_disable(panel->backlight.pwm);
 }
 
-void intel_panel_disable_backlight(struct intel_connector *connector)
+void intel_panel_disable_backlight(const struct drm_connector_state *old_conn_state)
 {
+	struct intel_connector *connector = to_intel_connector(old_conn_state->connector);
 	struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
 	struct intel_panel *panel = &connector->panel;
 
@@ -830,13 +852,15 @@ void intel_panel_disable_backlight(struct intel_connector *connector)
 	if (panel->backlight.device)
 		panel->backlight.device->props.power = FB_BLANK_POWERDOWN;
 	panel->backlight.enabled = false;
-	panel->backlight.disable(connector);
+	panel->backlight.disable(old_conn_state);
 
 	mutex_unlock(&dev_priv->backlight_lock);
 }
 
-static void lpt_enable_backlight(struct intel_connector *connector)
+static void lpt_enable_backlight(const struct intel_crtc_state *crtc_state,
+				 const struct drm_connector_state *conn_state)
 {
+	struct intel_connector *connector = to_intel_connector(conn_state->connector);
 	struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
 	struct intel_panel *panel = &connector->panel;
 	u32 pch_ctl1, pch_ctl2, schicken;
@@ -880,16 +904,16 @@ static void lpt_enable_backlight(struct intel_connector *connector)
 	I915_WRITE(BLC_PWM_PCH_CTL1, pch_ctl1 | BLM_PCH_PWM_ENABLE);
 
 	/* This won't stick until the above enable. */
-	intel_panel_actually_set_backlight(connector, panel->backlight.level);
+	intel_panel_actually_set_backlight(conn_state, panel->backlight.level);
 }
 
-static void pch_enable_backlight(struct intel_connector *connector)
+static void pch_enable_backlight(const struct intel_crtc_state *crtc_state,
+				 const struct drm_connector_state *conn_state)
 {
+	struct intel_connector *connector = to_intel_connector(conn_state->connector);
 	struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
 	struct intel_panel *panel = &connector->panel;
-	enum pipe pipe = intel_get_pipe_from_connector(connector);
-	enum transcoder cpu_transcoder =
-		intel_pipe_to_cpu_transcoder(dev_priv, pipe);
+	enum transcoder cpu_transcoder = crtc_state->cpu_transcoder;
 	u32 cpu_ctl2, pch_ctl1, pch_ctl2;
 
 	cpu_ctl2 = I915_READ(BLC_PWM_CPU_CTL2);
@@ -915,7 +939,7 @@ static void pch_enable_backlight(struct intel_connector *connector)
 	I915_WRITE(BLC_PWM_CPU_CTL2, cpu_ctl2 | BLM_PWM_ENABLE);
 
 	/* This won't stick until the above enable. */
-	intel_panel_actually_set_backlight(connector, panel->backlight.level);
+	intel_panel_actually_set_backlight(conn_state, panel->backlight.level);
 
 	pch_ctl2 = panel->backlight.max << 16;
 	I915_WRITE(BLC_PWM_PCH_CTL2, pch_ctl2);
@@ -929,8 +953,10 @@ static void pch_enable_backlight(struct intel_connector *connector)
 	I915_WRITE(BLC_PWM_PCH_CTL1, pch_ctl1 | BLM_PCH_PWM_ENABLE);
 }
 
-static void i9xx_enable_backlight(struct intel_connector *connector)
+static void i9xx_enable_backlight(const struct intel_crtc_state *crtc_state,
+				  const struct drm_connector_state *conn_state)
 {
+	struct intel_connector *connector = to_intel_connector(conn_state->connector);
 	struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
 	struct intel_panel *panel = &connector->panel;
 	u32 ctl, freq;
@@ -955,7 +981,7 @@ static void i9xx_enable_backlight(struct intel_connector *connector)
 	POSTING_READ(BLC_PWM_CTL);
 
 	/* XXX: combine this into above write? */
-	intel_panel_actually_set_backlight(connector, panel->backlight.level);
+	intel_panel_actually_set_backlight(conn_state, panel->backlight.level);
 
 	/*
 	 * Needed to enable backlight on some 855gm models. BLC_HIST_CTL is
@@ -966,11 +992,13 @@ static void i9xx_enable_backlight(struct intel_connector *connector)
 		I915_WRITE(BLC_HIST_CTL, BLM_HISTOGRAM_ENABLE);
 }
 
-static void i965_enable_backlight(struct intel_connector *connector)
+static void i965_enable_backlight(const struct intel_crtc_state *crtc_state,
+				  const struct drm_connector_state *conn_state)
 {
+	struct intel_connector *connector = to_intel_connector(conn_state->connector);
 	struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
 	struct intel_panel *panel = &connector->panel;
-	enum pipe pipe = intel_get_pipe_from_connector(connector);
+	enum pipe pipe = to_intel_crtc(conn_state->crtc)->pipe;
 	u32 ctl, ctl2, freq;
 
 	ctl2 = I915_READ(BLC_PWM_CTL2);
@@ -996,19 +1024,18 @@ static void i965_enable_backlight(struct intel_connector *connector)
 	POSTING_READ(BLC_PWM_CTL2);
 	I915_WRITE(BLC_PWM_CTL2, ctl2 | BLM_PWM_ENABLE);
 
-	intel_panel_actually_set_backlight(connector, panel->backlight.level);
+	intel_panel_actually_set_backlight(conn_state, panel->backlight.level);
 }
 
-static void vlv_enable_backlight(struct intel_connector *connector)
+static void vlv_enable_backlight(const struct intel_crtc_state *crtc_state,
+				 const struct drm_connector_state *conn_state)
 {
+	struct intel_connector *connector = to_intel_connector(conn_state->connector);
 	struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
 	struct intel_panel *panel = &connector->panel;
-	enum pipe pipe = intel_get_pipe_from_connector(connector);
+	enum pipe pipe = to_intel_crtc(crtc_state->base.crtc)->pipe;
 	u32 ctl, ctl2;
 
-	if (WARN_ON(pipe != PIPE_A && pipe != PIPE_B))
-		return;
-
 	ctl2 = I915_READ(VLV_BLC_PWM_CTL2(pipe));
 	if (ctl2 & BLM_PWM_ENABLE) {
 		DRM_DEBUG_KMS("backlight already enabled\n");
@@ -1020,7 +1047,7 @@ static void vlv_enable_backlight(struct intel_connector *connector)
 	I915_WRITE(VLV_BLC_PWM_CTL(pipe), ctl);
 
 	/* XXX: combine this into above write? */
-	intel_panel_actually_set_backlight(connector, panel->backlight.level);
+	intel_panel_actually_set_backlight(conn_state, panel->backlight.level);
 
 	ctl2 = 0;
 	if (panel->backlight.active_low_pwm)
@@ -1030,11 +1057,13 @@ static void vlv_enable_backlight(struct intel_connector *connector)
 	I915_WRITE(VLV_BLC_PWM_CTL2(pipe), ctl2 | BLM_PWM_ENABLE);
 }
 
-static void bxt_enable_backlight(struct intel_connector *connector)
+static void bxt_enable_backlight(const struct intel_crtc_state *crtc_state,
+				 const struct drm_connector_state *conn_state)
 {
+	struct intel_connector *connector = to_intel_connector(conn_state->connector);
 	struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
 	struct intel_panel *panel = &connector->panel;
-	enum pipe pipe = intel_get_pipe_from_connector(connector);
+	enum pipe pipe = to_intel_crtc(crtc_state->base.crtc)->pipe;
 	u32 pwm_ctl, val;
 
 	/* Controller 1 uses the utility pin. */
@@ -1064,7 +1093,7 @@ static void bxt_enable_backlight(struct intel_connector *connector)
 	I915_WRITE(BXT_BLC_PWM_FREQ(panel->backlight.controller),
 			panel->backlight.max);
 
-	intel_panel_actually_set_backlight(connector, panel->backlight.level);
+	intel_panel_actually_set_backlight(conn_state, panel->backlight.level);
 
 	pwm_ctl = 0;
 	if (panel->backlight.active_low_pwm)
@@ -1076,19 +1105,54 @@ static void bxt_enable_backlight(struct intel_connector *connector)
 			pwm_ctl | BXT_BLC_PWM_ENABLE);
 }
 
-static void pwm_enable_backlight(struct intel_connector *connector)
+static void cnp_enable_backlight(const struct intel_crtc_state *crtc_state,
+				 const struct drm_connector_state *conn_state)
 {
+	struct intel_connector *connector = to_intel_connector(conn_state->connector);
+	struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
+	struct intel_panel *panel = &connector->panel;
+	u32 pwm_ctl;
+
+	pwm_ctl = I915_READ(BXT_BLC_PWM_CTL(panel->backlight.controller));
+	if (pwm_ctl & BXT_BLC_PWM_ENABLE) {
+		DRM_DEBUG_KMS("backlight already enabled\n");
+		pwm_ctl &= ~BXT_BLC_PWM_ENABLE;
+		I915_WRITE(BXT_BLC_PWM_CTL(panel->backlight.controller),
+			   pwm_ctl);
+	}
+
+	I915_WRITE(BXT_BLC_PWM_FREQ(panel->backlight.controller),
+		   panel->backlight.max);
+
+	intel_panel_actually_set_backlight(conn_state, panel->backlight.level);
+
+	pwm_ctl = 0;
+	if (panel->backlight.active_low_pwm)
+		pwm_ctl |= BXT_BLC_PWM_POLARITY;
+
+	I915_WRITE(BXT_BLC_PWM_CTL(panel->backlight.controller), pwm_ctl);
+	POSTING_READ(BXT_BLC_PWM_CTL(panel->backlight.controller));
+	I915_WRITE(BXT_BLC_PWM_CTL(panel->backlight.controller),
+		   pwm_ctl | BXT_BLC_PWM_ENABLE);
+}
+
+static void pwm_enable_backlight(const struct intel_crtc_state *crtc_state,
+				 const struct drm_connector_state *conn_state)
+{
+	struct intel_connector *connector = to_intel_connector(conn_state->connector);
 	struct intel_panel *panel = &connector->panel;
 
 	pwm_enable(panel->backlight.pwm);
-	intel_panel_actually_set_backlight(connector, panel->backlight.level);
+	intel_panel_actually_set_backlight(conn_state, panel->backlight.level);
 }
 
-void intel_panel_enable_backlight(struct intel_connector *connector)
+void intel_panel_enable_backlight(const struct intel_crtc_state *crtc_state,
+				  const struct drm_connector_state *conn_state)
 {
+	struct intel_connector *connector = to_intel_connector(conn_state->connector);
 	struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
 	struct intel_panel *panel = &connector->panel;
-	enum pipe pipe = intel_get_pipe_from_connector(connector);
+	enum pipe pipe = to_intel_crtc(crtc_state->base.crtc)->pipe;
 
 	if (!panel->backlight.present)
 		return;
@@ -1108,7 +1172,7 @@ void intel_panel_enable_backlight(struct intel_connector *connector)
 						 panel->backlight.device->props.max_brightness);
 	}
 
-	panel->backlight.enable(connector);
+	panel->backlight.enable(crtc_state, conn_state);
 	panel->backlight.enabled = true;
 	if (panel->backlight.device)
 		panel->backlight.device->props.power = FB_BLANK_UNBLANK;
@@ -1126,7 +1190,7 @@ static int intel_backlight_device_update_status(struct backlight_device *bd)
 	drm_modeset_lock(&dev->mode_config.connection_mutex, NULL);
 	DRM_DEBUG_KMS("updating intel_backlight, brightness=%d/%d\n",
 		      bd->props.brightness, bd->props.max_brightness);
-	intel_panel_set_backlight(connector, bd->props.brightness,
+	intel_panel_set_backlight(connector->base.state, bd->props.brightness,
 				  bd->props.max_brightness);
 
 	/*
@@ -1239,6 +1303,17 @@ void intel_backlight_device_unregister(struct intel_connector *connector)
 #endif /* CONFIG_BACKLIGHT_CLASS_DEVICE */
 
 /*
+ * CNP: PWM clock frequency is 19.2 MHz or 24 MHz.
+ *      PWM increment = 1
+ */
+static u32 cnp_hz_to_pwm(struct intel_connector *connector, u32 pwm_freq_hz)
+{
+	struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
+
+	return DIV_ROUND_CLOSEST(KHz(dev_priv->rawclk_freq), pwm_freq_hz);
+}
+
+/*
  * BXT: PWM clock frequency = 19.2 MHz.
  */
 static u32 bxt_hz_to_pwm(struct intel_connector *connector, u32 pwm_freq_hz)
@@ -1633,6 +1708,42 @@ bxt_setup_backlight(struct intel_connector *connector, enum pipe unused)
 	return 0;
 }
 
+static int
+cnp_setup_backlight(struct intel_connector *connector, enum pipe unused)
+{
+	struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
+	struct intel_panel *panel = &connector->panel;
+	u32 pwm_ctl, val;
+
+	/*
+	 * CNP has the BXT implementation of backlight, but with only
+	 * one controller. Future platforms could have multiple controllers
+	 * so let's make this extensible and prepared for the future.
+	 */
+	panel->backlight.controller = 0;
+
+	pwm_ctl = I915_READ(BXT_BLC_PWM_CTL(panel->backlight.controller));
+
+	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);
+	val = intel_panel_compute_brightness(connector, val);
+	panel->backlight.level = clamp(val, panel->backlight.min,
+				       panel->backlight.max);
+
+	panel->backlight.enabled = pwm_ctl & BXT_BLC_PWM_ENABLE;
+
+	return 0;
+}
+
 static int pwm_setup_backlight(struct intel_connector *connector,
 			       enum pipe pipe)
 {
@@ -1749,6 +1860,13 @@ intel_panel_init_backlight_funcs(struct intel_panel *panel)
 		panel->backlight.set = bxt_set_backlight;
 		panel->backlight.get = bxt_get_backlight;
 		panel->backlight.hz_to_pwm = bxt_hz_to_pwm;
+	} else if (HAS_PCH_CNP(dev_priv)) {
+		panel->backlight.setup = cnp_setup_backlight;
+		panel->backlight.enable = cnp_enable_backlight;
+		panel->backlight.disable = cnp_disable_backlight;
+		panel->backlight.set = bxt_set_backlight;
+		panel->backlight.get = bxt_get_backlight;
+		panel->backlight.hz_to_pwm = cnp_hz_to_pwm;
 	} else if (HAS_PCH_LPT(dev_priv) || HAS_PCH_SPT(dev_priv) ||
 		   HAS_PCH_KBP(dev_priv)) {
 		panel->backlight.setup = lpt_setup_backlight;