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authorAlex Deucher <alexdeucher@gmail.com>2014-05-08 18:58:04 +0400
committerAlex Deucher <alexander.deucher@amd.com>2014-06-02 18:25:02 +0400
commit831719d62f692e28699a7acd7b441c6f0c01b6f7 (patch)
tree7f9bcfe0d74ae6cae476ab9b597b1a6abfd80446 /drivers/gpu/drm/radeon/radeon_i2c.c
parent182407a6ed5333fc37dd980a8de91a8f826a94f6 (diff)
downloadlinux-831719d62f692e28699a7acd7b441c6f0c01b6f7.tar.xz
drm/radeon: add a i2c bus mutex
The i2c and aux buses use the same pads so add a mutex to protect access to the pads. Signed-off-by: Alex Deucher <alexander.deucher@amd.com> Signed-off-by: Christian König <christian.koenig@amd.com>
Diffstat (limited to 'drivers/gpu/drm/radeon/radeon_i2c.c')
-rw-r--r--drivers/gpu/drm/radeon/radeon_i2c.c9
1 files changed, 9 insertions, 0 deletions
diff --git a/drivers/gpu/drm/radeon/radeon_i2c.c b/drivers/gpu/drm/radeon/radeon_i2c.c
index 7b944142a9fd..427ee4d6d0b5 100644
--- a/drivers/gpu/drm/radeon/radeon_i2c.c
+++ b/drivers/gpu/drm/radeon/radeon_i2c.c
@@ -94,6 +94,8 @@ static int pre_xfer(struct i2c_adapter *i2c_adap)
struct radeon_i2c_bus_rec *rec = &i2c->rec;
uint32_t temp;
+ mutex_lock(&i2c->mutex);
+
/* RV410 appears to have a bug where the hw i2c in reset
* holds the i2c port in a bad state - switch hw i2c away before
* doing DDC - do this for all r200s/r300s/r400s for safety sake
@@ -170,6 +172,8 @@ static void post_xfer(struct i2c_adapter *i2c_adap)
temp = RREG32(rec->mask_data_reg) & ~rec->mask_data_mask;
WREG32(rec->mask_data_reg, temp);
temp = RREG32(rec->mask_data_reg);
+
+ mutex_unlock(&i2c->mutex);
}
static int get_clock(void *i2c_priv)
@@ -813,6 +817,8 @@ static int radeon_hw_i2c_xfer(struct i2c_adapter *i2c_adap,
struct radeon_i2c_bus_rec *rec = &i2c->rec;
int ret = 0;
+ mutex_lock(&i2c->mutex);
+
switch (rdev->family) {
case CHIP_R100:
case CHIP_RV100:
@@ -879,6 +885,8 @@ static int radeon_hw_i2c_xfer(struct i2c_adapter *i2c_adap,
break;
}
+ mutex_unlock(&i2c->mutex);
+
return ret;
}
@@ -919,6 +927,7 @@ struct radeon_i2c_chan *radeon_i2c_create(struct drm_device *dev,
i2c->adapter.dev.parent = &dev->pdev->dev;
i2c->dev = dev;
i2c_set_adapdata(&i2c->adapter, i2c);
+ mutex_init(&i2c->mutex);
if (rec->mm_i2c ||
(rec->hw_capable &&
radeon_hw_i2c &&