[PATCH 3.8 131/152] radeon/i2c: do not count reg index in number of i2c byte we are writing.

[Kamal Mostafa]

3.8.13.14 -stable review patch.  If anyone has any objections, please let me know.

------------------

From: Jerome Glisse <jglisse at redhat.com>

commit fae009d15a44e5f1d938340facf4b8bc7dc69a09 upstream.

Useless to count the register index in number of bytes we are writing.

Fixes a regression with hw i2c enabled.

Signed-off-by: Jerome Glisse <jglisse at redhat.com>
Signed-off-by: Alex Deucher <alexander.deucher at amd.com>
[ kamal: backport to 3.8 (context) ]
Signed-off-by: Kamal Mostafa <kamal at canonical.com>
---
 drivers/gpu/drm/radeon/atombios_i2c.c | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/radeon/atombios_i2c.c b/drivers/gpu/drm/radeon/atombios_i2c.c
index 2ca389d..4bb4b7a 100644
--- a/drivers/gpu/drm/radeon/atombios_i2c.c
+++ b/drivers/gpu/drm/radeon/atombios_i2c.c
@@ -55,7 +55,10 @@ static int radeon_process_i2c_ch(struct radeon_i2c_chan *chan,
 			DRM_ERROR("hw i2c: tried to write too many bytes (%d vs 2)\n", num);
 			return -EINVAL;
 		}
-		memcpy(&out, buf, num);
+		if (num > 1) {
+			num--;
+			memcpy(&out, &buf[1], num);
+		}
 		args.lpI2CDataOut = cpu_to_le16(out);
 	} else {
 		if (num > ATOM_MAX_HW_I2C_READ) {
-- 
1.8.3.2