Hi Jacopo, On Wed, Apr 29, 2020 at 09:02:15AM +0200, Jacopo Mondi wrote: > Hi Sakari, > > On Wed, Apr 29, 2020 at 12:26:43AM +0300, Sakari Ailus wrote: > > Hi Jacopo, > > > > On Tue, Apr 28, 2020 at 11:06:07PM +0200, Jacopo Mondi wrote: > > > A sub-device device node can be registered in user space only if the > > > CONFIG_V4L2_SUBDEV_API Kconfig option is selected. > > > > > > Remove checks from the v4l2-subdev file handle open/close functions and > > > ioctl handler as they are only accessible if a device node was registered > > > to user space in first place. > > > > Is there other motivation with this than clean up things a little? > > > > I had to add yet-another #if defined and I got fed up. If you don't > have a device node registered you won't be able to access any of the > functions where the existing #if defined() where placed. > > > The change increases the binary size marginally if the Kconfig option is > > disabled. > > > > I see. Should we instead guard the whole file handle operations and > ioctl handler instead of having #if defined() spread inside them ? I > assume they where there as leftover, as I'm still missing the point, > give that, as said, without V4L2_SUBDEV_API, you can't register any > device node to userspace.. I think that's why those #ifdefs have been originally put there --- it's just dead code without the subdev nodes, and the compiler won't be able to figure this out. But it seems, later on, when people have added code that supports sub-device nodes, no #ifdefs have been added. I think I'd make sense to remove the current #ifdefs and add dummy ops for everything where needed that truly depends on that Kconfig option (i.e. sub-device nodes). Or just to remove these, as your patch does. It's not a lot of code. -- Kind regards, Sakari Ailus
