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