Hi Ezequiel, On Sun, Mar 28, 2021 at 10:27:35AM -0300, Ezequiel Garcia wrote: > On Tue, 2021-03-23 at 21:27 +0200, Sakari Ailus wrote: > > Hi Ezequiel, > > > > On Tue, Mar 23, 2021 at 02:46:04PM -0300, Ezequiel Garcia wrote: > > > On Fri, 2021-03-12 at 14:56 +0200, Sakari Ailus wrote: > > > > The V4L2 async framework is generally used with the V4L2 fwnode, which > > > > also depends on the former. There is only one exception, the CAFE_CCIC > > > > driver, which uses V4L2 async but does not need V4L2 fwnode. > > > > > > > > At the same time there is a vast number of systems that need videodev > > > > module, but have no use for v4l2-async that's now part of videodev. > > > > > > > > In order to improve, build v4l2-async and v4l2-fwnode as a single module > > > > called v4l2-async (the v4l2-async.c file is renamed as v4l2-async-core.c). > > > > Also the menu item V4L2_FWNODE is renamed as V4L2_ASYNC. > > > > > > > > > > Seems this is not what this patch is doing: the symbol is not renamed, > > > and now we have two modules v4l2-fwnode.ko and v4l2-async.ko, unless > > > I'm confused. > > > > Oh, well, I changed what the patch does but forgot to update this. :-I > > > > Basically this now splits v4l2-async out of videodev. > > > > > > > > I personally was more fond of having just one v4l2-async.ko module, > > > but I'm not sure if you found any obstacles. > > > > > > > This also moves the initialisation of the debufs entries for async subdevs > > > > to loading of the v4l2-async module. The directory is named as > > > > "v4l2-async". > > > > > > > > Signed-off-by: Sakari Ailus <sakari.ailus@xxxxxxxxxxxxxxx> > > > > --- > > > > drivers/media/i2c/Kconfig | 8 ++++++++ > > > > drivers/media/v4l2-core/Kconfig | 4 ++++ > > > > drivers/media/v4l2-core/Makefile | 11 +++++++++-- > > > > drivers/media/v4l2-core/v4l2-async.c | 23 +++++++++++++++++++++-- > > > > drivers/media/v4l2-core/v4l2-dev.c | 5 ----- > > > > 5 files changed, 42 insertions(+), 9 deletions(-) > > > > > > > [..] > > > > diff --git a/drivers/media/v4l2-core/Makefile b/drivers/media/v4l2-core/Makefile > > > > index e4cd589b99a5..eb5ebb5461fd 100644 > > > > --- a/drivers/media/v4l2-core/Makefile > > > > +++ b/drivers/media/v4l2-core/Makefile > > > > @@ -7,15 +7,22 @@ tuner-objs := tuner-core.o > > > > > > > > videodev-objs := v4l2-dev.o v4l2-ioctl.o v4l2-device.o v4l2-fh.o \ > > > > v4l2-event.o v4l2-ctrls.o v4l2-subdev.o \ > > > > - v4l2-async.o v4l2-common.o > > > > + v4l2-common.o > > > > videodev-$(CONFIG_COMPAT) += v4l2-compat-ioctl32.o > > > > videodev-$(CONFIG_TRACEPOINTS) += v4l2-trace.o > > > > videodev-$(CONFIG_MEDIA_CONTROLLER) += v4l2-mc.o > > > > videodev-$(CONFIG_SPI) += v4l2-spi.o > > > > videodev-$(CONFIG_VIDEO_V4L2_I2C) += v4l2-i2c.o > > > > > > > > -obj-$(CONFIG_V4L2_FWNODE) += v4l2-fwnode.o > > > > obj-$(CONFIG_VIDEO_V4L2) += videodev.o > > > > +ifneq ($(findstring y,$(CONFIG_V4L2_ASYNC)$(CONFIG_V4L2_FWNODE)),) > > > > > > Hm, to me this ifdefery is an indication that we are trying > > > to do something fishy. > > > > What's happening here is that v4l2-fwnode depends on v4l2-async, but for > > drivers to avoid selecting both, v4l2-async is built if only > > CONFIG_V4L2_FWNODE is set. > > > > So this perhaps isn't too pretty but it saves hassle in Kconfig files. > > > > How about: > > v4l2-async-objs := v4l2-async-core.o > v4l2-async-$(CONFIG_V4L2_FWNODE) += v4l2-fwnode.o > obj-$(CONFIG_V4L2_ASYNC) += v4l2-async.o > > config V4L2_FWNODE > bool > select V4L2_ASYNC Drivers are using select to enable V4L2_FWNODE. Select will select the config option but will not care about its dependencies, i.e. V4L2_ASYNC in this case. I guess another option could be just to sprinkle both in Kconfig files as needed. I'm fraknkly not too concerned about the few lines in the Makefile. If there's a need to get rid of them, there's always an easy way to get rid of it. > > config V4L2_ASYNC > tristate > > This avoids the ifdefs and expresses the same behavior > you stated above: > > * v4l2-async is now out of videodev > * v4l2-fwnode depends on v4l2-async (through select in this case, > given they are helper modules). > * v4l2-async is built if CONFIG_V4L2_FWNODE is set. > > And v4l2-async is a module or built-in, depending on the > media subsystem (MEDIA_SUPPORT) being module or built-in, > which I think makes sense. -- Kind regards, Sakari Ailus
