Hello,
This series enables usage of the ADV748x after the system have been
suspended to ram. During s2ram the ADV748x may be powered down and thus
lose its configuration from probe time. The configuration contains
among other things the i2c slave address mappings for the different
blocks inside the ADV748x. If this is lost the hardware listens to the
"wrong" i2c addresses and becomes inaccessible.
Example trying to read the analog standard before and after s2ram with
and without this this series.
Without this series,
# subdev=$(grep -l "adv748x 4-0070 afe" /sys/class/video4linux/*/name | sed 's#.*video4linux\(.*\)/name#/dev\1#g')
# v4l2-ctl --get-detected-standard -d $subdev
Video Standard = 0x000000ff
PAL-B/B1/G/H/I/D/D1/K
# echo on > /sys/bus/i2c/drivers/bd9571mwv/*/bd9571mwv-regulator*/backup_mode
** flipp SW23 off **
# echo mem > /sys/power/state
** flipp SW23 on **
# v4l2-ctl --get-detected-standard -d $subdev
[ 502.753723] adv748x 4-0070: error reading 63, 02
[ 502.866437] adv748x 4-0070: error reading 63, 02
VIDIOC_QUERYSTD: failed: No such device or address
With this series,
# subdev=$(grep -l "adv748x 4-0070 afe" /sys/class/video4linux/*/name | sed 's#.*video4linux\(.*\)/name#/dev\1#g')
# v4l2-ctl --get-detected-standard -d $subdev
Video Standard = 0x000000ff
PAL-B/B1/G/H/I/D/D1/K
# echo on > /sys/bus/i2c/drivers/bd9571mwv/*/bd9571mwv-regulator*/backup_mode
** flipp SW23 off **
# echo mem > /sys/power/state
** flipp SW23 on **
# v4l2-ctl --get-detected-standard -d $subdev
Video Standard = 0x000000ff
PAL-B/B1/G/H/I/D/D1/K
Also any streaming while the system is suspended to ram fails to resume
without this series due to the issue demonstrated above. This series is
tested on R-Car M3-N on-top of latest media-tree.
Niklas Söderlund (3):
adv748x: afe: Select input port when device is reset
adv748x: csi2: Set virtual channel when device is reset
adv748x: Configure device when resuming from sleep
drivers/media/i2c/adv748x/adv748x-afe.c | 6 +----
drivers/media/i2c/adv748x/adv748x-core.c | 29 ++++++++++++++++++++++--
drivers/media/i2c/adv748x/adv748x-csi2.c | 6 +----
drivers/media/i2c/adv748x/adv748x.h | 2 ++
4 files changed, 31 insertions(+), 12 deletions(-)
--
2.29.2
