openkylin
/
linux
mirror of https://gitee.com/openkylin/linux.git
9
0
Fork 0
Code Issues Projects Releases Wiki Activity

drm/i915: Fix DDC on some systems by clearing BIOS GMBUS setup. 

This is a sync of a fix I made in the old UMS code.  If the BIOS uses
the GMBUS and doesn't clear that setup, then our bit-banging I2C can
fail, leading to monitors not being detected.

Signed-off-by: Eric Anholt <eric@anholt.net>
This commit is contained in:
Eric Anholt 2009-12-01 11:56:30 -08:00
parent d09c23de9f
commit f0217c42c9
4 changed files with 39 additions and 1 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

14
drivers/gpu/drm/i915/i915_reg.h
View File

@ -414,6 +414,13 @@
# define GPIO_DATA_VAL_IN (1 << 12)
# define GPIO_DATA_PULLUP_DISABLE (1 << 13)
#define GMBUS0 0x5100
#define GMBUS1 0x5104
#define GMBUS2 0x5108
#define GMBUS3 0x510c
#define GMBUS4 0x5110
#define GMBUS5 0x5120
/*
* Clock control & power management
*/
@ -2166,6 +2173,13 @@
#define PCH_GPIOE 0xc5020
#define PCH_GPIOF 0xc5024
#define PCH_GMBUS0 0xc5100
#define PCH_GMBUS1 0xc5104
#define PCH_GMBUS2 0xc5108
#define PCH_GMBUS3 0xc510c
#define PCH_GMBUS4 0xc5110
#define PCH_GMBUS5 0xc5120
#define PCH_DPLL_A 0xc6014
#define PCH_DPLL_B 0xc6018

5
drivers/gpu/drm/i915/i915_suspend.c
View File

@ -27,7 +27,7 @@
#include "drmP.h"
#include "drm.h"
#include "i915_drm.h"
#include "i915_drv.h"
#include "intel_drv.h"
static bool i915_pipe_enabled(struct drm_device *dev, enum pipe pipe)
{
@ -816,6 +816,9 @@ int i915_restore_state(struct drm_device *dev)
for (i = 0; i < 3; i++)
I915_WRITE(SWF30 + (i << 2), dev_priv->saveSWF2[i]);
/* I2C state */
intel_i2c_reset_gmbus(dev);
return 0;
}

2
drivers/gpu/drm/i915/intel_drv.h
View File

@ -162,6 +162,8 @@ void intel_i2c_destroy(struct i2c_adapter *adapter);
int intel_ddc_get_modes(struct intel_output *intel_output);
extern bool intel_ddc_probe(struct intel_output *intel_output);
void intel_i2c_quirk_set(struct drm_device *dev, bool enable);
void intel_i2c_reset_gmbus(struct drm_device *dev);
extern void intel_crt_init(struct drm_device *dev);
extern void intel_hdmi_init(struct drm_device *dev, int sdvox_reg);
extern bool intel_sdvo_init(struct drm_device *dev, int output_device);

19
drivers/gpu/drm/i915/intel_i2c.c
View File

@ -118,6 +118,23 @@ static void set_data(void *data, int state_high)
udelay(I2C_RISEFALL_TIME); /* wait for the line to change state */
}
/* Clears the GMBUS setup. Our driver doesn't make use of the GMBUS I2C
* engine, but if the BIOS leaves it enabled, then that can break our use
* of the bit-banging I2C interfaces. This is notably the case with the
* Mac Mini in EFI mode.
*/
void
intel_i2c_reset_gmbus(struct drm_device *dev)
{
struct drm_i915_private *dev_priv = dev->dev_private;
if (IS_IGDNG(dev)) {
I915_WRITE(PCH_GMBUS0, 0);
} else {
I915_WRITE(GMBUS0, 0);
}
}
/**
* intel_i2c_create - instantiate an Intel i2c bus using the specified GPIO reg
* @dev: DRM device
@ -168,6 +185,8 @@ struct i2c_adapter *intel_i2c_create(struct drm_device *dev, const u32 reg,
if(i2c_bit_add_bus(&chan->adapter))
goto out_free;
intel_i2c_reset_gmbus(dev);
/* JJJ: raise SCL and SDA? */
intel_i2c_quirk_set(dev, true);
set_data(chan, 1);