[v3 7/7] drm/i915: Backlight control using CRC PMIC based PWM driver
Shobhit Kumar
shobhit.kumar at intel.com
Fri Jun 26 02:02:10 PDT 2015
Use the CRC PWM device in intel_panel.c and add new MIPI backlight
specififc callbacks
v2: Modify to use pwm_config callback
v3: Addressed Jani's comments
- Renamed all function as pwm_* instead of vlv_*
- Call intel_panel_actually_set_backlight in enable function
- Return -ENODEV in case pwm_get fails
- in case pwm_config error return error cdoe from pwm_config
- Cleanup pwm in intel_panel_destroy_backlight
v4: Removed unused #defines and initialized backlight with INVALID_PIPE (Ville)
CC: Samuel Ortiz <sameo at linux.intel.com>
Cc: Linus Walleij <linus.walleij at linaro.org>
Cc: Alexandre Courbot <gnurou at gmail.com>
Cc: Thierry Reding <thierry.reding at gmail.com>
Reviewed-by: Ville Syrjälä <ville.syrjala at linux.intel.com>
Tested-by: Ville Syrjälä <ville.syrjala at linux.intel.com>
Signed-off-by: Shobhit Kumar <shobhit.kumar at intel.com>
---
drivers/gpu/drm/i915/intel_drv.h | 4 ++
drivers/gpu/drm/i915/intel_dsi.c | 5 ++
drivers/gpu/drm/i915/intel_panel.c | 94 ++++++++++++++++++++++++++++++++++++--
3 files changed, 98 insertions(+), 5 deletions(-)
diff --git a/drivers/gpu/drm/i915/intel_drv.h b/drivers/gpu/drm/i915/intel_drv.h
index 2afb31a..561c17f 100644
--- a/drivers/gpu/drm/i915/intel_drv.h
+++ b/drivers/gpu/drm/i915/intel_drv.h
@@ -182,6 +182,10 @@ struct intel_panel {
bool enabled;
bool combination_mode; /* gen 2/4 only */
bool active_low_pwm;
+
+ /* PWM chip */
+ struct pwm_device *pwm;
+
struct backlight_device *device;
} backlight;
diff --git a/drivers/gpu/drm/i915/intel_dsi.c b/drivers/gpu/drm/i915/intel_dsi.c
index c4db74a..892b936 100644
--- a/drivers/gpu/drm/i915/intel_dsi.c
+++ b/drivers/gpu/drm/i915/intel_dsi.c
@@ -402,6 +402,8 @@ static void intel_dsi_enable(struct intel_encoder *encoder)
intel_dsi_port_enable(encoder);
}
+
+ intel_panel_enable_backlight(intel_dsi->attached_connector);
}
static void intel_dsi_pre_enable(struct intel_encoder *encoder)
@@ -466,6 +468,8 @@ static void intel_dsi_pre_disable(struct intel_encoder *encoder)
DRM_DEBUG_KMS("\n");
+ intel_panel_disable_backlight(intel_dsi->attached_connector);
+
if (is_vid_mode(intel_dsi)) {
/* Send Shutdown command to the panel in LP mode */
for_each_dsi_port(port, intel_dsi->ports)
@@ -1132,6 +1136,7 @@ void intel_dsi_init(struct drm_device *dev)
}
intel_panel_init(&intel_connector->panel, fixed_mode, NULL);
+ intel_panel_setup_backlight(connector, INVALID_PIPE);
return;
diff --git a/drivers/gpu/drm/i915/intel_panel.c b/drivers/gpu/drm/i915/intel_panel.c
index 7d83527..952fadc 100644
--- a/drivers/gpu/drm/i915/intel_panel.c
+++ b/drivers/gpu/drm/i915/intel_panel.c
@@ -32,8 +32,11 @@
#include <linux/kernel.h>
#include <linux/moduleparam.h>
+#include <linux/pwm.h>
#include "intel_drv.h"
+#define CRC_PMIC_PWM_PERIOD_NS 21333
+
void
intel_fixed_panel_mode(const struct drm_display_mode *fixed_mode,
struct drm_display_mode *adjusted_mode)
@@ -544,6 +547,15 @@ static u32 bxt_get_backlight(struct intel_connector *connector)
return I915_READ(BXT_BLC_PWM_DUTY1);
}
+static u32 pwm_get_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;
@@ -632,6 +644,14 @@ static void bxt_set_backlight(struct intel_connector *connector, u32 level)
I915_WRITE(BXT_BLC_PWM_DUTY1, level);
}
+static void pwm_set_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)
{
@@ -769,6 +789,16 @@ static void bxt_disable_backlight(struct intel_connector *connector)
I915_WRITE(BXT_BLC_PWM_CTL1, tmp & ~BXT_BLC_PWM_ENABLE);
}
+static void pwm_disable_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;
@@ -1002,6 +1032,14 @@ static void bxt_enable_backlight(struct intel_connector *connector)
I915_WRITE(BXT_BLC_PWM_CTL1, pwm_ctl | BXT_BLC_PWM_ENABLE);
}
+static void pwm_enable_backlight(struct intel_connector *connector)
+{
+ struct intel_panel *panel = &connector->panel;
+
+ pwm_enable(panel->backlight.pwm);
+ intel_panel_actually_set_backlight(connector, panel->backlight.level);
+}
+
void intel_panel_enable_backlight(struct intel_connector *connector)
{
struct drm_device *dev = connector->base.dev;
@@ -1378,6 +1416,40 @@ bxt_setup_backlight(struct intel_connector *connector, enum pipe unused)
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;
+}
+
int intel_panel_setup_backlight(struct drm_connector *connector, enum pipe pipe)
{
struct drm_device *dev = connector->dev;
@@ -1421,6 +1493,10 @@ void intel_panel_destroy_backlight(struct drm_connector *connector)
struct intel_connector *intel_connector = to_intel_connector(connector);
struct intel_panel *panel = &intel_connector->panel;
+ /* dispose of the pwm */
+ if (panel->backlight.pwm)
+ pwm_put(panel->backlight.pwm);
+
panel->backlight.present = false;
}
@@ -1448,11 +1524,19 @@ 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 = pwm_setup_backlight;
+ dev_priv->display.enable_backlight = pwm_enable_backlight;
+ dev_priv->display.disable_backlight = pwm_disable_backlight;
+ dev_priv->display.set_backlight = pwm_set_backlight;
+ dev_priv->display.get_backlight = pwm_get_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;
--
1.9.1
More information about the dri-devel
mailing list