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authorAlex Deucher <alexdeucher@gmail.com>2014-05-08 10:58:04 -0400
committerAlex Deucher <alexander.deucher@amd.com>2014-06-02 10:25:02 -0400
commit831719d62f692e28699a7acd7b441c6f0c01b6f7 (patch)
tree7f9bcfe0d74ae6cae476ab9b597b1a6abfd80446 /drivers/gpu/drm/radeon/atombios_i2c.c
parent182407a6ed5333fc37dd980a8de91a8f826a94f6 (diff)
downloadlinux-831719d62f692e28699a7acd7b441c6f0c01b6f7.tar.bz2
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/atombios_i2c.c')
-rw-r--r--drivers/gpu/drm/radeon/atombios_i2c.c17
1 files changed, 13 insertions, 4 deletions
diff --git a/drivers/gpu/drm/radeon/atombios_i2c.c b/drivers/gpu/drm/radeon/atombios_i2c.c
index b5162c3b6111..9c570fb15b8c 100644
--- a/drivers/gpu/drm/radeon/atombios_i2c.c
+++ b/drivers/gpu/drm/radeon/atombios_i2c.c
@@ -43,15 +43,19 @@ static int radeon_process_i2c_ch(struct radeon_i2c_chan *chan,
int index = GetIndexIntoMasterTable(COMMAND, ProcessI2cChannelTransaction);
unsigned char *base;
u16 out = cpu_to_le16(0);
+ int r = 0;
memset(&args, 0, sizeof(args));
+ mutex_lock(&chan->mutex);
+
base = (unsigned char *)rdev->mode_info.atom_context->scratch;
if (flags & HW_I2C_WRITE) {
if (num > ATOM_MAX_HW_I2C_WRITE) {
DRM_ERROR("hw i2c: tried to write too many bytes (%d vs 3)\n", num);
- return -EINVAL;
+ r = -EINVAL;
+ goto done;
}
if (buf == NULL)
args.ucRegIndex = 0;
@@ -65,7 +69,8 @@ static int radeon_process_i2c_ch(struct radeon_i2c_chan *chan,
} else {
if (num > ATOM_MAX_HW_I2C_READ) {
DRM_ERROR("hw i2c: tried to read too many bytes (%d vs 255)\n", num);
- return -EINVAL;
+ r = -EINVAL;
+ goto done;
}
args.ucRegIndex = 0;
args.lpI2CDataOut = 0;
@@ -82,13 +87,17 @@ static int radeon_process_i2c_ch(struct radeon_i2c_chan *chan,
/* error */
if (args.ucStatus != HW_ASSISTED_I2C_STATUS_SUCCESS) {
DRM_DEBUG_KMS("hw_i2c error\n");
- return -EIO;
+ r = -EIO;
+ goto done;
}
if (!(flags & HW_I2C_WRITE))
radeon_atom_copy_swap(buf, base, num, false);
- return 0;
+done:
+ mutex_unlock(&chan->mutex);
+
+ return r;
}
int radeon_atom_hw_i2c_xfer(struct i2c_adapter *i2c_adap,