Hi Sakari, On Fri, Mar 11, 2022 at 03:15:54PM +0200, Sakari Ailus wrote: > On Fri, Mar 11, 2022 at 02:30:09PM +0200, Laurent Pinchart wrote: > > On Fri, Mar 11, 2022 at 02:23:53PM +0200, Sakari Ailus wrote: > > > On Fri, Mar 11, 2022 at 08:12:59PM +0900, Paul Elder wrote: > > > > Switch to using runtime PM for power management. > > > > > > > > Signed-off-by: Paul Elder <paul.elder@xxxxxxxxxxxxxxxx> > > > > > > > > --- > > > > Changes in v2: > > > > - replace manual tracking of power status with pm_runtime_get_if_in_use > > > > - power on the sensor before reading the checking the chip id > > > > - add dependency on PM to Kconfig > > > > --- > > > > drivers/media/i2c/Kconfig | 1 + > > > > drivers/media/i2c/ov5640.c | 112 ++++++++++++++++++++++--------------- > > > > 2 files changed, 67 insertions(+), 46 deletions(-) > > > > > > > > diff --git a/drivers/media/i2c/Kconfig b/drivers/media/i2c/Kconfig > > > > index e7194c1be4d2..97c3611d9304 100644 > > > > --- a/drivers/media/i2c/Kconfig > > > > +++ b/drivers/media/i2c/Kconfig > > > > @@ -1025,6 +1025,7 @@ config VIDEO_OV5640 > > > > tristate "OmniVision OV5640 sensor support" > > > > depends on OF > > > > depends on GPIOLIB && VIDEO_V4L2 && I2C > > > > + depends on PM > > > > > > I think this is not needed as the sensor is powered on explicitly in probe. > > > > > > You should similarly power it off explicitly in remove, set the runtime PM > > > status suspended and disable runtime PM. See e.g. imx319 driver for an > > > example. It doesn't have resume callback but that doesn't really matter --- > > > it's just ACPI-only. > > > > Do we want to continue supporting !PM ? Does it have any real use case > > when dealing with camera sensors ? > > Probably not much. > > The changes I proposed are not eve related on runtime PM. Hence the > question here is whether there should be a dependency to CONFIG_PM or not, > and as there's no technical reason to have it, it should be omitted. But if there's no real use case for !PM, wouldn't we be better off depending on PM and simplifying the probe functions instead ? -- Regards, Laurent Pinchart
