Right now we power-up the device when a user open() the device and we power it off when the last user close() the first video node. This behaviour affects the power consumption of the device is multiple use cases, such as: - Polling the privacy gpio - udev probing the device This patchset introduces a more granular power saving behaviour where the camera is only awaken when needed. It is compatible with asynchronous controls. While developing this patchset, two bugs were found. The patchset has been developed so these fixes can be taken independently. Signed-off-by: Ricardo Ribalda <ribalda@xxxxxxxxxxxx> --- Changes in v4: - CodeStyle - Create uvc_pm_ functions - Link to v3: https://lore.kernel.org/r/20250206-uvc-granpower-ng-v3-0-32d0d7b0c5d8@xxxxxxxxxxxx Changes in v3: - Fix build error on sh4. - Link to v2: https://lore.kernel.org/r/20250203-uvc-granpower-ng-v2-0-bef4b55e7b67@xxxxxxxxxxxx Changes in v2: - Add missing semicolon. - Rebase on top of media-committers/next - Link to v1: https://lore.kernel.org/r/20241126-uvc-granpower-ng-v1-0-6312bf26549c@xxxxxxxxxxxx --- Ricardo Ribalda (5): media: uvcvideo: Keep streaming state in the file handle media: uvcvideo: Create uvc_pm_(get|put) functions media: uvcvideo: Increase/decrease the PM counter per IOCTL media: uvcvideo: Make power management granular media: uvcvideo: Do not turn on the camera for some ioctls drivers/media/usb/uvc/uvc_ctrl.c | 13 +++++- drivers/media/usb/uvc/uvc_v4l2.c | 99 ++++++++++++++++++++++++++++++---------- drivers/media/usb/uvc/uvcvideo.h | 6 +++ 3 files changed, 92 insertions(+), 26 deletions(-) --- base-commit: d98e9213a768a3cc3a99f5e1abe09ad3baff2104 change-id: 20241126-uvc-granpower-ng-069185a6d474 Best regards, -- Ricardo Ribalda <ribalda@xxxxxxxxxxxx>
