shinys000114/linux
1
0
Fork 0
mirror of https://github.com/hardkernel/linux.git synced 2026-06-06 19:08:57 +09:00
Code Issues Packages Projects Releases Wiki Activity

adv7604: Initialize drive strength to default when using DT

Browse Source 
[ Upstream commit da8892d410 ]

The adv7604 driver platform data contains fields for configuring the drive
strength of the output pins. When probing the driver through DT these
fields are not explicitly initialized, which means they are left at 0. This
is a reserved setting for the drive strength configuration though and can
cause signal integrity issues.

Whether these signal integrity issues are visible depends on the PCB
specifics (e.g. the higher the load capacitance for the output the more
visible the issue). But it has been observed on existing solutions at high
pixel clock rates.

Initialize the drive strength settings to the power-on-reset value of the
device when probing through devicetree to avoid this issue.

Fixes: 0e158be0162b ("adv7604: Add DT support")

Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Tested-by: Niklas Söderlund <niklas.soderlund+renesas@ragnatech.se>
Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>
Signed-off-by: Sasha Levin <alexander.levin@verizon.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
Lars-Peter Clausen
2016-11-29 09:23:48 -02:00
committed by Greg Kroah-Hartman
parent 5caae9d141
commit 95e5e7ed5a
1 changed files with 3 additions and 0 deletions
Download Patch File Download Diff File Expand all files Collapse all files

3
drivers/media/i2c/adv7604.c
View File

@@ -3118,6 +3118,9 @@ static int adv76xx_parse_dt(struct adv76xx_state *state)
state->pdata.blank_data = 1;
state->pdata.op_format_mode_sel = ADV7604_OP_FORMAT_MODE0;
state->pdata.bus_order = ADV7604_BUS_ORDER_RGB;
state->pdata.dr_str_data = ADV76XX_DR_STR_MEDIUM_HIGH;
state->pdata.dr_str_clk = ADV76XX_DR_STR_MEDIUM_HIGH;
state->pdata.dr_str_sync = ADV76XX_DR_STR_MEDIUM_HIGH;
return 0;
}