From 95e5e7ed5a8a64be3fffa56c1fdeae243f69e19c Mon Sep 17 00:00:00 2001 From: Lars-Peter Clausen Date: Tue, 29 Nov 2016 09:23:48 -0200 Subject: adv7604: Initialize drive strength to default when using DT MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit [ Upstream commit da8892d410db224d9a24104529794e6e37e0c100 ] 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 Reviewed-by: Laurent Pinchart Tested-by: Niklas Söderlund Signed-off-by: Hans Verkuil Signed-off-by: Mauro Carvalho Chehab Signed-off-by: Sasha Levin Signed-off-by: Greg Kroah-Hartman --- drivers/media/i2c/adv7604.c | 3 +++ 1 file changed, 3 insertions(+) (limited to 'drivers') diff --git a/drivers/media/i2c/adv7604.c b/drivers/media/i2c/adv7604.c index 4003831de712..7b1935ab03c8 100644 --- a/drivers/media/i2c/adv7604.c +++ b/drivers/media/i2c/adv7604.c @@ -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; } -- cgit v1.2.3