[PATCH 3.11 155/208] radeon/i2c: do not count reg index in number of i2c byte we are writing.

[Luis Henriques]

3.11.10.2 -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>
Signed-off-by: Luis Henriques <luis.henriques at canonical.com>
---
 drivers/gpu/drm/radeon/atombios_i2c.c | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/drivers/gpu/drm/radeon/atombios_i2c.c b/drivers/gpu/drm/radeon/atombios_i2c.c
index deaf98c..0652ee0 100644
--- a/drivers/gpu/drm/radeon/atombios_i2c.c
+++ b/drivers/gpu/drm/radeon/atombios_i2c.c
@@ -56,8 +56,10 @@ static int radeon_process_i2c_ch(struct radeon_i2c_chan *chan,
 			return -EINVAL;
 		}
 		args.ucRegIndex = buf[0];
-		if (num > 1)
-			memcpy(&out, &buf[1], num - 1);
+		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