Hi Laurent, > -----Original Message----- > From: Laurent Pinchart [mailto:laurent.pinchart@xxxxxxxxxxxxxxxx] > Sent: Monday, March 12, 2012 3:54 PM > To: Bhupesh SHARMA > Cc: linux-media@xxxxxxxxxxxxxxx; spear-devel > Subject: Re: [PATCH 1/1] V4L/v4l2-dev: Make 'videodev_init' as a subsys > initcall > > Hi Bhupesh, > > On Monday 12 March 2012 18:13:18 Bhupesh SHARMA wrote: > > On Monday, March 12, 2012 3:35 PM Laurent Pinchart wrote: > > > On Monday 12 March 2012 14:39:02 Bhupesh Sharma wrote: > > > > As the V4L2 based UVC webcam gadget (g_webcam) expects the > > > > 'videodev' to present when the 'webcam_bind' routine is called, > > > > so 'videodev' should be available as early as possible. > > > > > > > > Now, when 'g_webcam' is built as a module (i.e. not a part of > > > > kernel) the late availability of 'videodev' is OK, but if > > > > 'g_webcam' is built statically as a part of the kernel, > > > > the kernel crashes (a sample crash dump using Designware 2.0 UDC > > > > is provided below). > > > > > > > > To solve the same, this patch makes 'videodev_init' as a subsys > > > > > > initcall. > > > > > > > Kernel Crash Dump: > > > > ------------------ > > > > > > [snip] > > > > > > > Signed-off-by: Bhupesh Sharma <bhupesh.sharma@xxxxxx> > > > > --- > > > > > > > > drivers/media/video/v4l2-dev.c | 2 +- > > > > 1 files changed, 1 insertions(+), 1 deletions(-) > > > > > > > > diff --git a/drivers/media/video/v4l2-dev.c > > > > > > b/drivers/media/video/v4l2-dev.c > > > > > > > index 96e9615..041804b 100644 > > > > --- a/drivers/media/video/v4l2-dev.c > > > > +++ b/drivers/media/video/v4l2-dev.c > > > > @@ -788,7 +788,7 @@ static void __exit videodev_exit(void) > > > > > > > > unregister_chrdev_region(dev, VIDEO_NUM_DEVICES); > > > > > > > > } > > > > > > > > -module_init(videodev_init) > > > > +subsys_initcall(videodev_init); > > > > > > > > module_exit(videodev_exit) > > > > > > > > MODULE_AUTHOR("Alan Cox, Mauro Carvalho Chehab > > > > > > <mchehab@xxxxxxxxxxxxx>"); > > > > > > Shouldn't drivers/media/media-devnode.c then use subsys_initcall() > as > > > well ? > > > > Yes, it should. Do you want me to send a patch for the same also? > > > > But I have no platform to check whether the Media Controller changes > > for g_webcam work on a real platform (i.e. omap3isp), so can you > > kindly test the patch I send for the same on your setup? > > I'll test both on the OMAP3 ISP and I'll send a patch for media- > devnode.c. Ok thanks. Regards, Bhupesh -- To unsubscribe from this list: send the line "unsubscribe linux-media" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
