drm/i915: Backlight control using CRC PMIC based PWM driver

[android-x86/kernel.git] / drivers / gpu / drm / i915 / intel_panel.c

diff --git a/drivers/gpu/drm/i915/intel_panel.c b/drivers/gpu/drm/i915/intel_panel.c
index d8686ce..b3ed794 100644 (file)
--- a/drivers/gpu/drm/i915/intel_panel.c
+++ b/drivers/gpu/drm/i915/intel_panel.c
@@ -31,8 +31,12 @@
 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
 
 #include <linux/moduleparam.h>
+#include <linux/pwm.h>
 #include "intel_drv.h"
 
+#define CRC_PMIC_PWM_PERIOD_NS 21333
+#define CRC_PMIC_PWM_STEPS     255
+
 void
 intel_fixed_panel_mode(const struct drm_display_mode *fixed_mode,
                       struct drm_display_mode *adjusted_mode)
@@ -535,6 +539,15 @@ static u32 vlv_get_backlight(struct intel_connector *connector)
        return _vlv_get_backlight(dev, pipe);
 }
 
+static u32 vlv_get_mipi_backlight(struct intel_connector *connector)
+{
+       struct intel_panel *panel = &connector->panel;
+       int duty_ns;
+
+       duty_ns = pwm_get_duty_cycle(panel->backlight.pwm);
+       return DIV_ROUND_UP(duty_ns * 100, CRC_PMIC_PWM_PERIOD_NS);
+}
+
 static u32 intel_panel_get_backlight(struct intel_connector *connector)
 {
        struct drm_device *dev = connector->base.dev;
@@ -615,6 +628,14 @@ static void vlv_set_backlight(struct intel_connector *connector, u32 level)
        I915_WRITE(VLV_BLC_PWM_CTL(pipe), tmp | level);
 }
 
+static void vlv_set_mipi_backlight(struct intel_connector *connector, u32 level)
+{
+       struct intel_panel *panel = &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)
 {
@@ -740,6 +761,16 @@ static void vlv_disable_backlight(struct intel_connector *connector)
        I915_WRITE(VLV_BLC_PWM_CTL2(pipe), tmp & ~BLM_PWM_ENABLE);
 }
 
+static void vlv_disable_mipi_backlight(struct intel_connector *connector)
+{
+       struct intel_panel *panel = &connector->panel;
+
+       /* Disable the backlight */
+       pwm_config(panel->backlight.pwm, 0, CRC_PMIC_PWM_PERIOD_NS);
+       usleep_range(2000, 3000);
+       pwm_disable(panel->backlight.pwm);
+}
+
 void intel_panel_disable_backlight(struct intel_connector *connector)
 {
        struct drm_device *dev = connector->base.dev;
@@ -946,6 +977,16 @@ static void vlv_enable_backlight(struct intel_connector *connector)
        I915_WRITE(VLV_BLC_PWM_CTL2(pipe), ctl2 | BLM_PWM_ENABLE);
 }
 
+static void vlv_enable_mipi_backlight(struct intel_connector *connector)
+{
+       struct intel_panel *panel = &connector->panel;
+       int duty_ns = DIV_ROUND_UP(
+                       panel->backlight.level * CRC_PMIC_PWM_PERIOD_NS, 100);
+
+       pwm_enable(panel->backlight.pwm);
+       pwm_config(panel->backlight.pwm, duty_ns, CRC_PMIC_PWM_PERIOD_NS);
+}
+
 void intel_panel_enable_backlight(struct intel_connector *connector)
 {
        struct drm_device *dev = connector->base.dev;
@@ -1298,6 +1339,34 @@ static int vlv_setup_backlight(struct intel_connector *connector, enum pipe pipe
        return 0;
 }
 
+static int vlv_setup_mipi_backlight(struct intel_connector *connector, enum pipe pipe)
+{
+       struct drm_device *dev = connector->base.dev;
+       struct intel_panel *panel = &connector->panel;
+
+       /* Get the PWM chip for backlight control */
+       panel->backlight.pwm = pwm_get(dev->dev, "pwm_backlight");
+       if (IS_ERR(panel->backlight.pwm)) {
+               DRM_ERROR("Faild to own the pwm chip\n");
+               panel->backlight.pwm = NULL;
+       } else if (pwm_config(panel->backlight.pwm, CRC_PMIC_PWM_PERIOD_NS,
+                                               CRC_PMIC_PWM_PERIOD_NS) < 0) {
+               DRM_ERROR("Failed to configure the pwm chip\n");
+               pwm_put(panel->backlight.pwm);
+               panel->backlight.pwm = NULL;
+               return -1;
+       }
+
+       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 ? true : false;
+
+       return 0;
+}
+
 int intel_panel_setup_backlight(struct drm_connector *connector, enum pipe pipe)
 {
        struct drm_device *dev = connector->dev;
@@ -1362,11 +1431,19 @@ void intel_panel_init_backlight_funcs(struct drm_device *dev)
                dev_priv->display.set_backlight = pch_set_backlight;
                dev_priv->display.get_backlight = pch_get_backlight;
        } else if (IS_VALLEYVIEW(dev)) {
-               dev_priv->display.setup_backlight = vlv_setup_backlight;
-               dev_priv->display.enable_backlight = vlv_enable_backlight;
-               dev_priv->display.disable_backlight = vlv_disable_backlight;
-               dev_priv->display.set_backlight = vlv_set_backlight;
-               dev_priv->display.get_backlight = vlv_get_backlight;
+               if (dev_priv->vbt.has_mipi) {
+                       dev_priv->display.setup_backlight = vlv_setup_mipi_backlight;
+                       dev_priv->display.enable_backlight = vlv_enable_mipi_backlight;
+                       dev_priv->display.disable_backlight = vlv_disable_mipi_backlight;
+                       dev_priv->display.set_backlight = vlv_set_mipi_backlight;
+                       dev_priv->display.get_backlight = vlv_get_mipi_backlight;
+               } else {
+                       dev_priv->display.setup_backlight = vlv_setup_backlight;
+                       dev_priv->display.enable_backlight = vlv_enable_backlight;
+                       dev_priv->display.disable_backlight = vlv_disable_backlight;
+                       dev_priv->display.set_backlight = vlv_set_backlight;
+                       dev_priv->display.get_backlight = vlv_get_backlight;
+               }
        } else if (IS_GEN4(dev)) {
                dev_priv->display.setup_backlight = i965_setup_backlight;
                dev_priv->display.enable_backlight = i965_enable_backlight;
@@ -1403,6 +1480,11 @@ void intel_panel_fini(struct intel_panel *panel)
        if (panel->downclock_mode)
                drm_mode_destroy(intel_connector->base.dev,
                                panel->downclock_mode);
+
+       /* dispose of the pwm */
+       if (panel->backlight.pwm)
+               pwm_put(panel->backlight.pwm);
+
 }
 
 void intel_backlight_register(struct drm_device *dev)