This fixes a regression for SDVO from
commit fbfcc4f3a0cf8bbde87646b74241faa8e37426bf
Author: Jani Nikula <jani.nikula at intel.com>
Date: Mon Oct 22 16:12:18 2012 +0300
drm/i915/sdvo: restore i2c adapter config on intel_sdvo_init() failures
As SDVOB and SDVOC are multiplexed on the same pin, if a chipset does
not have the second SDVO encoder, it will then remove the force-bit
setting on the common i2c adapter during teardown. All subsequent
attempts of trying to use GMBUS with SDVOB then fail.
Signed-off-by: Chris Wilson <chris at chris-wilson.co.uk>
Cc: Jani Nikula <jani.nikula at intel.com>
Cc: Mika Kuoppala <mika.kuoppala at intel.com>
---
drivers/gpu/drm/i915/i915_drv.h | 2 +-
drivers/gpu/drm/i915/intel_i2c.c | 9 ++++++---
2 files changed, 7 insertions(+), 4 deletions(-)
diff --git a/drivers/gpu/drm/i915/i915_drv.h b/drivers/gpu/drm/i915/i915_drv.h
index c2daad1..cf407b1 100644
--- a/drivers/gpu/drm/i915/i915_drv.h
+++ b/drivers/gpu/drm/i915/i915_drv.h
@@ -394,7 +394,7 @@ struct intel_fbc_work;
struct intel_gmbus {
struct i2c_adapter adapter;
- bool force_bit;
+ u32 force_bit;
u32 reg0;
u32 gpio_reg;
struct i2c_algo_bit_data bit_algo;
diff --git a/drivers/gpu/drm/i915/intel_i2c.c b/drivers/gpu/drm/i915/intel_i2c.c
index 84b68a6..f8ca0be 100644
--- a/drivers/gpu/drm/i915/intel_i2c.c
+++ b/drivers/gpu/drm/i915/intel_i2c.c
@@ -482,7 +482,7 @@ timeout:
I915_WRITE(GMBUS0 + reg_offset, 0);
/* Hardware may not support GMBUS over these pins? Try GPIO bitbanging instead. */
- bus->force_bit = true;
+ bus->force_bit = 1;
ret = i2c_bit_algo.master_xfer(adapter, msgs, num);
out:
@@ -542,7 +542,7 @@ int intel_setup_gmbus(struct drm_device *dev)
/* gmbus seems to be broken on i830 */
if (IS_I830(dev))
- bus->force_bit = true;
+ bus->force_bit = 1;
intel_gpio_setup(bus, port);
@@ -583,7 +583,10 @@ void intel_gmbus_force_bit(struct i2c_adapter *adapter, bool force_bit)
{
struct intel_gmbus *bus = to_intel_gmbus(adapter);
- bus->force_bit = force_bit;
+ bus->force_bit += force_bit ? 1 : -1;
+ DRM_DEBUG_KMS("%sabling bit-banging on %s. force bit now %d\n",
+ force_bit ? "dis" : "en", adapter->name,
+ bus->force_bit);
}
void intel_teardown_gmbus(struct drm_device *dev)
--
1.7.10.4
