linux-stable/drivers/media
Lars-Peter Clausen da8892d410 [media] adv7604: Initialize drive strength to default when using DT
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>
2017-01-30 15:39:40 -02:00
..
cec
common
dvb-core
dvb-frontends
firewire
i2c [media] adv7604: Initialize drive strength to default when using DT 2017-01-30 15:39:40 -02:00
mmc
pci
platform [media] media: platform: soc_camera_platform : constify v4l2_subdev_* structures 2017-01-30 14:47:21 -02:00
radio
rc [media] staging: lirc_imon: port remaining usb ids to imon and remove 2017-01-30 14:34:57 -02:00
spi
tuners
usb
v4l2-core
cec-edid.c
Kconfig
Makefile
media-device.c
media-devnode.c
media-entity.c