On 03/09/2025 16:35, Niklas Söderlund wrote: > Hi Hans, > > Thanks for your review effort! > > On 2025-09-03 10:46:11 +0200, Hans Verkuil wrote: >> On 28/08/2025 18:06, Niklas Söderlund wrote: >>> Hello, >>> >>> This series started as an effort to fix issues with querystd. To do that >>> it turned out the whole drivers design around how it controls the power >>> to the video decoder block inside the chip had to be reworked. As a >>> bonus this works removes the now deprecated .s_power callback from >>> adv7180. >>> >>> The adv7180 drivers comes from a time before media controller and all >>> operation callbacks are, more or less, designed around the concept that >>> a video device is the only user-space facing API. In that world a vdev >>> would attached the subdevice, call .s_power and then perform format >>> configuration using the other operation callbacks and then start >>> streaming with .s_stream. Needles to say this mode of operation don't >>> work well with media controller where the subdevices itself have a >>> user-space API exposed thru a subdev device. >>> >>> The initial problem I tried to solve (querystd) was that it stopped >>> functioning as expected after the subdev had been used to stream once >>> (.s_power(1), .s_power(0)). As it turns out different variants of the >>> adv7180 device have different reset beaver for if its video decoder >>> block is left running or powered off. On my device it was left running >>> so querystd functioned the first time, but not after the video decoder >>> had been switched off once by .s_power(0). >>> >>> I first tried to fix this by introducing proper PM handling in the >>> driver to be able to remove the .s_power callback. I quickly learnt the >>> power on/off logic happening in the driver had noting to do with >>> controlling power to the chip itself, but to control if the chips video >>> decoder block was turned off. >>> >>> When this block is powered on the device process video data, if there is >>> a video source else it free runs. However when the block is turned off >>> the device can still be configured, in fact some configuration requires >>> it to be off. >>> >>> For this reason I dropped the effort to add proper PM handling and >>> treated the decoder power as a stream on/off switch. I still think >>> proper PM handling would be beneficial for this driver but to not >>> explode this already large series I left that for another time. Solving >>> the issue around .s_power will make that work easier as well as other >>> task such as converting to the v4l2_subdev active state API. >>> >>> Patch 1/11 just moves code around to make the consecutive changes easier >>> to read. Patch 2/11 fix a locking issues when suspending the device. >>> Patch 3/11 and 4/11 improves the locking design to prepare to improve >>> the driver. >>> >>> Patch 5/11 make sure the device controls are always programmed after the >>> device have been reset, fixing a possible issue when the device where >>> resumed from system sleep. >>> >>> Patches 6/11, 7/11 and 8/11 is the real change where the .s_power >>> callback is reworked to fit the design of .s_stream instead. >>> >>> And finally patch 9/11, 10/11 and 11/11 removes programming of the >>> device from operation callbacks and solves the issue with querystd. >>> >>> The work is tested on R-Car M2 together with a ADV7180 device. >>> >>> See individual patches for changelog. >> >> This series looks good to me, other than the one typo and the >> control handler kAPI issue, but that can be done in a follow-up >> series. >> >> If you want I can take this series, let me know. > > Thanks for pointing out the improvement in the kAPI, I agree with it. > But as you point out I can do that in follow up work so I would be happy > if you would take this series. Can you correct the typo while applying, > or would you prefer I send an undated series? I'll correct the typo. Regards, Hans > >> >> Regards, >> >> Hans >> >>> >>> Niklas Söderlund (11): >>> media: adv7180: Move adv7180_set_power() and init_device() >>> media: adv7180: Add missing lock in suspend callback >>> media: adv7180: Move state mutex handling outside init_device() >>> media: adv7180: Use v4l2-ctrls core to handle s_ctrl locking >>> media: adv7180: Setup controls every time the device is reset >>> media: adv7180: Power down decoder when configuring the device >>> media: adv7180: Split device initialization and reset >>> media: adv7180: Remove the s_power callback >>> media: adv7180: Do not write format to device in set_fmt >>> media: adv7180: Only validate format in s_std >>> media: adv7180: Only validate format in querystd >>> >>> drivers/media/i2c/adv7180.c | 338 +++++++++++++++++++----------------- >>> 1 file changed, 174 insertions(+), 164 deletions(-) >>> >> >
