From 80deff17b2ffdbfbe4a0cd19fb500b77030004fc Mon Sep 17 00:00:00 2001 From: yetta_wu Date: Wed, 24 Jul 2013 16:37:57 +0800 Subject: [PATCH] display: slimport: prevent EDID overwritten Information from slimport vendor: With the wrong value set to SP_TX_AUX_CTRL_REG2, 7808 will try to write 0x00 to a random offset of EDID in the monitor. if the monitor's EDID is over written, we make it a bad EDID; with a bad EDID, AP will output 640x480p only normally. But most of monitors have write protection of EDID, 7808 is not able over write it. This issue not able to be reproduced with a monitor with EDID write protection. We have to fix this bug in case the very unlucky end user has a monitor without EDID write protection. Issue 10062852 Change-Id: Id8eff5a77154d648c8eb5046ef1cf35f4f9a712d Signed-off-by: yetta_wu --- drivers/misc/slimport_anx7808/slimport_tx_drv.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/misc/slimport_anx7808/slimport_tx_drv.c b/drivers/misc/slimport_anx7808/slimport_tx_drv.c index 06cac2b7d5f..8cb2fbd9fb9 100644 --- a/drivers/misc/slimport_anx7808/slimport_tx_drv.c +++ b/drivers/misc/slimport_anx7808/slimport_tx_drv.c @@ -2307,7 +2307,7 @@ void sp_tx_edid_read(void) bedid_break = 0; sp_tx_addronly_set(1); sp_write_reg(TX_P0, SP_TX_AUX_CTRL_REG, 0x04); - sp_write_reg(TX_P0, SP_TX_AUX_CTRL_REG2, 0x01); + sp_write_reg(TX_P0, SP_TX_AUX_CTRL_REG2, 0x03); sp_tx_wait_aux_finished(); edid_block = sp_tx_get_edid_block();