Re: [BUG/RFC PATCH 1/5] [BUG][RFC] media: atomisp: pci: assume run_mode is PREVIEW

[Tsuchiya Yuto <kitakar@gmail.com>]

<Adding back people/list to Cc>

On Fri, 2021-10-29 at 10:02 +0100, Mauro Carvalho Chehab wrote:
> Em Mon, 18 Oct 2021 01:23:32 +0900
> Tsuchiya Yuto <kitakar@gmail.com> escreveu:
> 
> > This is almost a BUG report with a patch to just make atomisp work
> > again with the current mainline kernel. Thus, prefixed with [BUG][RFC].
> > 
> > RFC:
> >   1. When looking at the `case CI_MODE_NONE:`, it tries to do something.
> >      So, it should rather work with CI_MODE_NONE, too? Just I don't know
> >      how to configure userspace apps to use CI_MODE_NONE ?
> >   2. How can we re-add the run mode support again without relying on
> >      the s_parm ?
> > 
> > > 8-----------------------------------------------------------------8<  
> > 
> > After the commit 8a7c5594c020 ("media: v4l2-ioctl: clear fields in s_parm")
> > added on v4.18 (backported to v4.9.182 and v4.14.127), the capture mode
> > flag is cleared (except for V4L2_MODE_HIGHQUALITY).
> > 
> > Due to this, it seems that now we can't use this flag to set atomisp
> > run_mode. This results in capture not working with the following message
> > (loaded atomisp driver with dbg_level=1):
> > 
> > 	kern  :warn  : [ 3658.776616] ia_css_pipe_get_info: ia_css_stream_create needs to be called before ia_css_[stream/pipe]_get_info
> > 	kern  :err   : [ 3658.776641] atomisp-isp2 0000:00:03.0: get_frame_info 1920x1080 (padded to 0)
> > 	kern  :warn  : [ 3658.776666] atomisp-isp2 0000:00:03.0: Can't set format on ISP. Error -22
> > 
> > So, when we can't detect run mode from the s_parm capturemode
> > (CI_MODE_NONE), let's assume the run mode is PREVIEW.
> 
> The run_mode on this driver is related to how camera works on Android.
> On such systems, camera have a preview mode, which is what the user
> views at the camera display. This is usually set to the display
> resolution (or to some other resolution that would allow a high
> fps rate). When the photo button is clicked, it sets the camera to
> the highest resolution mode (by default), which usually means a low
> fps rate.

Thank you for the description. I always wondered why they needed to
introduce run mode stuff.

> This doesn't make much sense on desktops, nor standard Linux apps
> support that.
> 
> Anyway, after looking on this patch, I guess the best is to apply
> this patch instead:
> 
> 	https://lore.kernel.org/linux-media/543e61dd07c90a7d8577b3a94696edc77953b9d8.1635497370.git.mchehab+huawei@kernel.org/T/#u
> 
> As a plus side, it is also one step further to allow generic apps to
> use the atomisp driver.
> 
> Applying it allowed me to do:
> 
> 	$ v4l2grab -D -f 'NV12' -x 1600 -y 1200 -d /dev/video2 -u
> 	$ nvt/raw2pnm -x1600 -y1200 -f NV12 out017.raw out017.pnm
> 	$ feh out017.pnm
> 
> So, I'm dropping patch 1/5 from media_stage, replacing it by the one which
> sets the mode after open().

Sorry for a bit late reply, I checked the capture functionality with the
latest media_stage patches and can confirm capture is still working
regarding this run_mode issue.

So, I agree to replace this my patch with yours. Thanks!

Regards,
Tsuchiya Yuto

> Regards,
> Mauro
> 
> > 
> > Signed-off-by: Tsuchiya Yuto <kitakar@gmail.com>
> > ---
> >  drivers/staging/media/atomisp/pci/atomisp_ioctl.c | 6 +++++-
> >  1 file changed, 5 insertions(+), 1 deletion(-)
> > 
> > diff --git a/drivers/staging/media/atomisp/pci/atomisp_ioctl.c b/drivers/staging/media/atomisp/pci/atomisp_ioctl.c
> > index c8a625667e81..6fc64f0ccc31 100644
> > --- a/drivers/staging/media/atomisp/pci/atomisp_ioctl.c
> > +++ b/drivers/staging/media/atomisp/pci/atomisp_ioctl.c
> > @@ -2638,7 +2638,11 @@ static int atomisp_s_parm(struct file *file, void *fh,
> >  				asd->high_speed_mode = true;
> >  		}
> >  
> > -		goto out;
> > +		dev_warn(isp->dev,
> > +			 "setting run_mode using s_parm capturemode is not supported anymore\n");
> > +		dev_warn(isp->dev, "assuming run_mode is PREVIEW\n");
> > +		mode = ATOMISP_RUN_MODE_PREVIEW;
> > +		break;
> >  	}
> >  	case CI_MODE_VIDEO:
> >  		mode = ATOMISP_RUN_MODE_VIDEO;