[Intel-gfx] [PATCH] i915: Add native backlight support
Matthew Garrett
mjg at redhat.com
Mon Feb 22 18:05:06 CET 2010
Some machines do not provide a firmware or platform interface to backlight
control, and so it's necessary to drive the hardware directly. Add support
for a backlight driver to the drm. This will be flagged with the raw
backlight type, allowing userspace to determine whether there is a more
favourable backlight device available.
Signed-off-by: Matthew Garrett <mjg at redhat.com>
---
drivers/gpu/drm/i915/i915_drv.h | 2 +
drivers/gpu/drm/i915/i915_opregion.c | 69 +---------------
drivers/gpu/drm/i915/intel_drv.h | 3 +
drivers/gpu/drm/i915/intel_lvds.c | 151 +++++++++++++++++++++++++++++++---
4 files changed, 147 insertions(+), 78 deletions(-)
diff --git a/drivers/gpu/drm/i915/i915_drv.h b/drivers/gpu/drm/i915/i915_drv.h
index b99b6a8..e77ecc2 100644
--- a/drivers/gpu/drm/i915/i915_drv.h
+++ b/drivers/gpu/drm/i915/i915_drv.h
@@ -33,6 +33,7 @@
#include "i915_reg.h"
#include "intel_bios.h"
#include <linux/io-mapping.h>
+#include <linux/backlight.h>
/* General customization:
*/
@@ -590,6 +591,7 @@ typedef struct drm_i915_private {
int child_dev_num;
struct child_device_config *child_dev;
struct drm_connector *int_lvds_connector;
+ struct backlight_device *backlight;
} drm_i915_private_t;
/** driver private structure attached to each drm_gem_object */
diff --git a/drivers/gpu/drm/i915/i915_opregion.c b/drivers/gpu/drm/i915/i915_opregion.c
index 7cc8410..d62a05d 100644
--- a/drivers/gpu/drm/i915/i915_opregion.c
+++ b/drivers/gpu/drm/i915/i915_opregion.c
@@ -31,9 +31,9 @@
#include "drmP.h"
#include "i915_drm.h"
#include "i915_drv.h"
+#include "intel_drv.h"
#define PCI_ASLE 0xe4
-#define PCI_LBPC 0xf4
#define PCI_ASLS 0xfc
#define OPREGION_SZ (8*1024)
@@ -149,39 +149,8 @@ struct opregion_asle {
static u32 asle_set_backlight(struct drm_device *dev, u32 bclp)
{
- struct drm_i915_private *dev_priv = dev->dev_private;
- struct opregion_asle *asle = dev_priv->opregion.asle;
- u32 blc_pwm_ctl, blc_pwm_ctl2;
- u32 max_backlight, level, shift;
-
- if (!(bclp & ASLE_BCLP_VALID))
- return ASLE_BACKLIGHT_FAIL;
-
- bclp &= ASLE_BCLP_MSK;
- if (bclp < 0 || bclp > 255)
- return ASLE_BACKLIGHT_FAIL;
-
- blc_pwm_ctl = I915_READ(BLC_PWM_CTL);
- blc_pwm_ctl2 = I915_READ(BLC_PWM_CTL2);
-
- if (IS_I965G(dev) && (blc_pwm_ctl2 & BLM_COMBINATION_MODE))
- pci_write_config_dword(dev->pdev, PCI_LBPC, bclp);
- else {
- if (IS_PINEVIEW(dev)) {
- blc_pwm_ctl &= ~(BACKLIGHT_DUTY_CYCLE_MASK - 1);
- max_backlight = (blc_pwm_ctl & BACKLIGHT_MODULATION_FREQ_MASK) >>
- BACKLIGHT_MODULATION_FREQ_SHIFT;
- shift = BACKLIGHT_DUTY_CYCLE_SHIFT + 1;
- } else {
- blc_pwm_ctl &= ~BACKLIGHT_DUTY_CYCLE_MASK;
- max_backlight = ((blc_pwm_ctl & BACKLIGHT_MODULATION_FREQ_MASK) >>
- BACKLIGHT_MODULATION_FREQ_SHIFT) * 2;
- shift = BACKLIGHT_DUTY_CYCLE_SHIFT;
- }
- level = (bclp * max_backlight) / 255;
- I915_WRITE(BLC_PWM_CTL, blc_pwm_ctl | (level << shift));
- }
- asle->cblv = (bclp*0x64)/0xff | ASLE_CBLV_VALID;
+ u32 max = intel_lvds_get_max_backlight(dev);
+ intel_lvds_set_backlight(dev, max * bclp / 255);
return 0;
}
@@ -247,36 +216,6 @@ void opregion_asle_intr(struct drm_device *dev)
asle->aslc = asle_stat;
}
-static u32 asle_set_backlight_ironlake(struct drm_device *dev, u32 bclp)
-{
- struct drm_i915_private *dev_priv = dev->dev_private;
- struct opregion_asle *asle = dev_priv->opregion.asle;
- u32 cpu_pwm_ctl, pch_pwm_ctl2;
- u32 max_backlight, level;
-
- if (!(bclp & ASLE_BCLP_VALID))
- return ASLE_BACKLIGHT_FAILED;
-
- bclp &= ASLE_BCLP_MSK;
- if (bclp < 0 || bclp > 255)
- return ASLE_BACKLIGHT_FAILED;
-
- cpu_pwm_ctl = I915_READ(BLC_PWM_CPU_CTL);
- pch_pwm_ctl2 = I915_READ(BLC_PWM_PCH_CTL2);
- /* get the max PWM frequency */
- max_backlight = (pch_pwm_ctl2 >> 16) & BACKLIGHT_DUTY_CYCLE_MASK;
- /* calculate the expected PMW frequency */
- level = (bclp * max_backlight) / 255;
- /* reserve the high 16 bits */
- cpu_pwm_ctl &= ~(BACKLIGHT_DUTY_CYCLE_MASK);
- /* write the updated PWM frequency */
- I915_WRITE(BLC_PWM_CPU_CTL, cpu_pwm_ctl | level);
-
- asle->cblv = (bclp*0x64)/0xff | ASLE_CBLV_VALID;
-
- return 0;
-}
-
void ironlake_opregion_gse_intr(struct drm_device *dev)
{
struct drm_i915_private *dev_priv = dev->dev_private;
@@ -300,7 +239,7 @@ void ironlake_opregion_gse_intr(struct drm_device *dev)
}
if (asle_req & ASLE_SET_BACKLIGHT)
- asle_stat |= asle_set_backlight_ironlake(dev, asle->bclp);
+ asle_stat |= asle_set_backlight(dev, asle->bclp);
if (asle_req & ASLE_SET_PFIT) {
DRM_DEBUG_DRIVER("Pfit is not supported\n");
diff --git a/drivers/gpu/drm/i915/intel_drv.h b/drivers/gpu/drm/i915/intel_drv.h
index a51573d..9b898c9 100644
--- a/drivers/gpu/drm/i915/intel_drv.h
+++ b/drivers/gpu/drm/i915/intel_drv.h
@@ -171,6 +171,9 @@ extern void intel_dvo_init(struct drm_device *dev);
extern void intel_tv_init(struct drm_device *dev);
extern void intel_mark_busy(struct drm_device *dev, struct drm_gem_object *obj);
extern void intel_lvds_init(struct drm_device *dev);
+extern u32 intel_lvds_get_max_backlight(struct drm_device *dev);
+extern u32 intel_lvds_get_backlight(struct drm_device *dev);
+extern void intel_lvds_set_backlight(struct drm_device *dev, int level);
extern void intel_dp_init(struct drm_device *dev, int dp_reg);
void
intel_dp_set_m_n(struct drm_crtc *crtc, struct drm_display_mode *mode,
diff --git a/drivers/gpu/drm/i915/intel_lvds.c b/drivers/gpu/drm/i915/intel_lvds.c
index b1d0acb..56220d4 100644
--- a/drivers/gpu/drm/i915/intel_lvds.c
+++ b/drivers/gpu/drm/i915/intel_lvds.c
@@ -38,6 +38,7 @@
#include "i915_drm.h"
#include "i915_drv.h"
#include <linux/acpi.h>
+#include <linux/backlight.h>
/* Private structure for the integrated LVDS support */
struct intel_lvds_priv {
@@ -47,41 +48,160 @@ struct intel_lvds_priv {
};
/**
+ * Returns the maximum level of the backlight duty cycle field.
+ */
+u32 intel_lvds_get_max_backlight(struct drm_device *dev)
+{
+ struct drm_i915_private *dev_priv = dev->dev_private;
+ u32 reg;
+ int value;
+ bool combo;
+
+ if (IS_I965G(dev))
+ combo = I915_READ(BLC_PWM_CTL2) & BLM_COMBINATION_MODE;
+ else
+ combo = I915_READ(BLC_PWM_CTL) & BLM_LEGACY_MODE;
+
+ if (IS_IRONLAKE(dev))
+ reg = BLC_PWM_PCH_CTL2;
+ else
+ reg = BLC_PWM_CTL;
+
+ value = ((I915_READ(reg) & BACKLIGHT_MODULATION_FREQ_MASK) >>
+ BACKLIGHT_MODULATION_FREQ_SHIFT) * 2;
+
+ if (combo) {
+ value *= 0xff;
+ value /= 2;
+ }
+
+ return value;
+}
+
+/**
+ * Returns the level of the backlight duty cycle field.
+ */
+u32 intel_lvds_get_backlight(struct drm_device *dev)
+{
+ struct drm_i915_private *dev_priv = dev->dev_private;
+ u32 reg;
+ u8 lbpc;
+ int value;
+ bool combo;
+
+ if (IS_I965G(dev))
+ combo = I915_READ(BLC_PWM_CTL2) & BLM_COMBINATION_MODE;
+ else
+ combo = I915_READ(BLC_PWM_CTL) & BLM_LEGACY_MODE;
+
+ if (IS_IRONLAKE(dev))
+ reg = BLC_PWM_CPU_CTL;
+ else
+ reg = BLC_PWM_CTL;
+
+ value = I915_READ(reg) & BACKLIGHT_DUTY_CYCLE_MASK;
+
+ if (combo) {
+ value &= ~0x1;
+ pci_read_config_byte(dev->pdev, LBB, &lbpc);
+ value *= lbpc;
+ value /= 2;
+ }
+
+ return value;
+}
+
+/**
* Sets the backlight level.
*
* \param level backlight level, from 0 to intel_lvds_get_max_backlight().
*/
-static void intel_lvds_set_backlight(struct drm_device *dev, int level)
+void intel_lvds_set_backlight(struct drm_device *dev, int level)
{
struct drm_i915_private *dev_priv = dev->dev_private;
u32 blc_pwm_ctl, reg;
+ bool combo;
+ u8 lbpc;
+
+ if (IS_I965G(dev))
+ combo = I915_READ(BLC_PWM_CTL2) & BLM_COMBINATION_MODE;
+ else
+ combo = I915_READ(BLC_PWM_CTL) & BLM_LEGACY_MODE;
if (IS_IRONLAKE(dev))
reg = BLC_PWM_CPU_CTL;
else
reg = BLC_PWM_CTL;
+ if (combo) {
+ int maximum = intel_lvds_get_max_backlight(dev);
+ lbpc = level * 0xfe / maximum;
+ lbpc += 1;
+ pci_write_config_byte(dev->pdev, LBB, lbpc);
+ level /= lbpc;
+ level <<= 1;
+ }
+
blc_pwm_ctl = I915_READ(reg) & ~BACKLIGHT_DUTY_CYCLE_MASK;
I915_WRITE(reg, (blc_pwm_ctl |
- (level << BACKLIGHT_DUTY_CYCLE_SHIFT)));
+ (level << BACKLIGHT_DUTY_CYCLE_SHIFT)));
}
-/**
- * Returns the maximum level of the backlight duty cycle field.
- */
-static u32 intel_lvds_get_max_backlight(struct drm_device *dev)
+#ifdef CONFIG_BACKLIGHT_CLASS_DEVICE
+static int intel_lvds_update_status(struct backlight_device *bd)
+{
+ struct drm_device *dev = bl_get_data(bd);
+ intel_lvds_set_backlight(dev, bd->props.brightness);
+ return 0;
+}
+
+static int intel_lvds_get_brightness(struct backlight_device *bd)
+{
+ struct drm_device *dev = bl_get_data(bd);
+ return intel_lvds_get_backlight(dev);
+}
+
+struct backlight_ops intel_lvds_bl_ops = {
+ .update_status = intel_lvds_update_status,
+ .get_brightness = intel_lvds_get_brightness,
+};
+
+static int intel_lvds_backlight_setup(struct drm_device *dev)
{
struct drm_i915_private *dev_priv = dev->dev_private;
- u32 reg;
+ struct backlight_properties props;
+
+ props.max_brightness = intel_lvds_get_max_backlight(dev);
+ props.type = BACKLIGHT_RAW;
+ dev_priv->backlight = backlight_device_register("intel_backlight",
+ &dev->pdev->dev, dev,
+ &intel_lvds_bl_ops,
+ &props);
+ if (IS_ERR(dev_priv->backlight)) {
+ DRM_ERROR("Failed to register backlight: %ld\n",
+ PTR_ERR(dev_priv->backlight));
+ dev_priv->backlight = NULL;
+ }
+ dev_priv->backlight->props.brightness = intel_lvds_get_backlight(dev);
+ return 0;
+}
- if (IS_IRONLAKE(dev))
- reg = BLC_PWM_PCH_CTL2;
- else
- reg = BLC_PWM_CTL;
+static void intel_lvds_backlight_destroy(struct drm_device *dev) {
+ struct drm_i915_private *dev_priv = dev->dev_private;
+ if (dev_priv->backlight)
+ backlight_device_unregister(dev_priv->backlight);
+}
+#else
+static int intel_lvds_backlight_setup(struct drm_device *dev)
+{
+ return 0;
+}
- return ((I915_READ(reg) & BACKLIGHT_MODULATION_FREQ_MASK) >>
- BACKLIGHT_MODULATION_FREQ_SHIFT) * 2;
+static void intel_lvds_backlight_destroy(struct drm_device *dev)
+{
+ return;
}
+#endif
/**
* Sets the power state for the panel.
@@ -745,6 +865,8 @@ static void intel_lvds_destroy(struct drm_connector *connector)
struct intel_output *intel_output = to_intel_output(connector);
struct drm_i915_private *dev_priv = dev->dev_private;
+ intel_lvds_backlight_destroy(dev);
+
if (intel_output->ddc_bus)
intel_i2c_destroy(intel_output->ddc_bus);
if (dev_priv->lid_notifier.notifier_call)
@@ -1156,6 +1278,9 @@ out:
/* keep the LVDS connector */
dev_priv->int_lvds_connector = connector;
drm_sysfs_connector_add(connector);
+
+ intel_lvds_backlight_setup(dev);
+
return;
failed:
--
1.6.6.1
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