tegra124: set MOT bit for I2C-over-AUX

According to DP version 1.2a, The MOT (Middle-of-Transaction) bit
must be set when the I2C transaction does not stop with the current
AUX transaction.
Thus the correct steps for an I2C read shall be:
1. I2C command write with MOT set to 1
2. I2C command read to the same address with MOT set to 0

BUG=chrome-os-partner:27679
TEST=EDID data read from LP140WH8 panel is correct while it's a
repeated pattern of the first 16 bytes without this CL
BRANCH=none

Original-Change-Id: I0526beffb8852fbbe0eb5bb80e370261617a59b8
Original-Signed-off-by: Ken Chang <kenc@nvidia.com>
Original-Reviewed-on: https://chromium-review.googlesource.com/194915
Original-Reviewed-by: Tom Warren <twarren@nvidia.com>
Original-Reviewed-by: Hung-Te Lin <hungte@chromium.org>
(cherry picked from commit 466ab0e00744f79ae3720474140d95e5f0828de9)
Signed-off-by: Marc Jones <marc.jones@se-eng.com>

Change-Id: Ic8ad38b4b08989dd7178d59151e1e276b8a58439
Reviewed-on: http://review.coreboot.org/7763
Tested-by: build bot (Jenkins)
Reviewed-by: Stefan Reinauer <stefan.reinauer@coreboot.org>
This commit is contained in:
Ken Chang 2014-04-15 17:00:17 +08:00 committed by Marc Jones
parent 1a8e0af78b
commit 2d43a48158
1 changed files with 1 additions and 1 deletions

View File

@ -337,7 +337,7 @@ int tegra_dc_i2c_aux_read(struct tegra_dc_dp_data *dp, u32 i2c_addr,
u32 len = 1; u32 len = 1;
ret = tegra_dc_dpaux_write_chunk( ret = tegra_dc_dpaux_write_chunk(
dp, DPAUX_DP_AUXCTL_CMD_I2CWR, i2c_addr, dp, DPAUX_DP_AUXCTL_CMD_MOTWR, i2c_addr,
&addr, &len, aux_stat); &addr, &len, aux_stat);
if (ret) { if (ret) {
printk(BIOS_ERR, "%s: error sending address to read.\n", printk(BIOS_ERR, "%s: error sending address to read.\n",