From: Lars-Peter Clausen Date: Tue, 29 Nov 2016 11:23:48 +0000 (-0200) Subject: adv7604: Initialize drive strength to default when using DT X-Git-Tag: v4.4.98~52 X-Git-Url: http://git.ipfire.org/gitweb.cgi?a=commitdiff_plain;h=8a56b1b25e3cc47cafca99f18e4b17f2b7069424;p=thirdparty%2Fkernel%2Fstable.git adv7604: Initialize drive strength to default when using DT [ 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 --- diff --git a/drivers/media/i2c/adv7604.c b/drivers/media/i2c/adv7604.c index 01adcdc523466..a9e2722f5e228 100644 --- a/drivers/media/i2c/adv7604.c +++ b/drivers/media/i2c/adv7604.c @@ -2856,6 +2856,9 @@ static int adv76xx_parse_dt(struct adv76xx_state *state) state->pdata.alt_data_sat = 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; }