Re: [PATCH v8 1/2] Added Digiteq Automotive MGB4 driver

[Martin Tůma]

On 26. 07. 23 11:30, Hans Verkuil wrote:
> On 26/07/2023 11:14, Hans Verkuil wrote:
> > Hi Martin,
> >
> > On 04/07/2023 15:13, tumic@xxxxxxxxxx wrote:
> > > From: Martin Tůma <martin.tuma@xxxxxxxxxxxxxxxxxxxxx>
> > >
> > > Digiteq Automotive MGB4 is a modular frame grabber PCIe card for automotive
> > > video interfaces. As for now, two modules - FPD-Link and GMSL - are
> > > available and supported by the driver. The card has two inputs and two
> > > outputs (FPD-Link only).
> > >
> > > In addition to the video interfaces it also provides a trigger signal
> > > interface and a MTD interface for FPGA firmware upload.
> > >
> > > Signed-off-by: Martin Tůma <martin.tuma@xxxxxxxxxxxxxxxxxxxxx>
> > > ---
> > >   MAINTAINERS                             |   7 +
> > >   drivers/media/pci/Kconfig               |   1 +
> > >   drivers/media/pci/Makefile              |   1 +
> > >   drivers/media/pci/mgb4/Kconfig          |  17 +
> > >   drivers/media/pci/mgb4/Makefile         |   6 +
> > >   drivers/media/pci/mgb4/mgb4_cmt.c       | 244 +++++++
> > >   drivers/media/pci/mgb4/mgb4_cmt.h       |  17 +
> > >   drivers/media/pci/mgb4/mgb4_core.c      | 711 ++++++++++++++++++
> > >   drivers/media/pci/mgb4/mgb4_core.h      |  72 ++
> > >   drivers/media/pci/mgb4/mgb4_dma.c       | 123 ++++
> > >   drivers/media/pci/mgb4/mgb4_dma.h       |  18 +
> > >   drivers/media/pci/mgb4/mgb4_i2c.c       | 140 ++++
> > >   drivers/media/pci/mgb4/mgb4_i2c.h       |  35 +
> > >   drivers/media/pci/mgb4/mgb4_io.h        |  33 +
> > >   drivers/media/pci/mgb4/mgb4_regs.c      |  30 +
> > >   drivers/media/pci/mgb4/mgb4_regs.h      |  35 +
> > >   drivers/media/pci/mgb4/mgb4_sysfs.h     |  18 +
> > >   drivers/media/pci/mgb4/mgb4_sysfs_in.c  | 757 +++++++++++++++++++
> > >   drivers/media/pci/mgb4/mgb4_sysfs_out.c | 700 ++++++++++++++++++
> > >   drivers/media/pci/mgb4/mgb4_sysfs_pci.c |  71 ++
> > >   drivers/media/pci/mgb4/mgb4_trigger.c   | 208 ++++++
> > >   drivers/media/pci/mgb4/mgb4_trigger.h   |   8 +
> > >   drivers/media/pci/mgb4/mgb4_vin.c       | 930 ++++++++++++++++++++++++
> > >   drivers/media/pci/mgb4/mgb4_vin.h       |  69 ++
> > >   drivers/media/pci/mgb4/mgb4_vout.c      | 594 +++++++++++++++
> > >   drivers/media/pci/mgb4/mgb4_vout.h      |  65 ++
> > >   26 files changed, 4910 insertions(+)
> > >   create mode 100644 drivers/media/pci/mgb4/Kconfig
> > >   create mode 100644 drivers/media/pci/mgb4/Makefile
> > >   create mode 100644 drivers/media/pci/mgb4/mgb4_cmt.c
> > >   create mode 100644 drivers/media/pci/mgb4/mgb4_cmt.h
> > >   create mode 100644 drivers/media/pci/mgb4/mgb4_core.c
> > >   create mode 100644 drivers/media/pci/mgb4/mgb4_core.h
> > >   create mode 100644 drivers/media/pci/mgb4/mgb4_dma.c
> > >   create mode 100644 drivers/media/pci/mgb4/mgb4_dma.h
> > >   create mode 100644 drivers/media/pci/mgb4/mgb4_i2c.c
> > >   create mode 100644 drivers/media/pci/mgb4/mgb4_i2c.h
> > >   create mode 100644 drivers/media/pci/mgb4/mgb4_io.h
> > >   create mode 100644 drivers/media/pci/mgb4/mgb4_regs.c
> > >   create mode 100644 drivers/media/pci/mgb4/mgb4_regs.h
> > >   create mode 100644 drivers/media/pci/mgb4/mgb4_sysfs.h
> > >   create mode 100644 drivers/media/pci/mgb4/mgb4_sysfs_in.c
> > >   create mode 100644 drivers/media/pci/mgb4/mgb4_sysfs_out.c
> > >   create mode 100644 drivers/media/pci/mgb4/mgb4_sysfs_pci.c
> > >   create mode 100644 drivers/media/pci/mgb4/mgb4_trigger.c
> > >   create mode 100644 drivers/media/pci/mgb4/mgb4_trigger.h
> > >   create mode 100644 drivers/media/pci/mgb4/mgb4_vin.c
> > >   create mode 100644 drivers/media/pci/mgb4/mgb4_vin.h
> > >   create mode 100644 drivers/media/pci/mgb4/mgb4_vout.c
> > >   create mode 100644 drivers/media/pci/mgb4/mgb4_vout.h
> >
> > When I build with: make W=1 KCFLAGS=-Wmaybe-uninitialized
> >
> > I get this warning:
> >
> > drivers/media/pci/mgb4/mgb4_vout.c: In function 'mgb4_vout_create':
> > drivers/media/pci/mgb4/mgb4_vout.c:473:27: warning: variable 'video' set but not used [-Wunused-but-set-variable]
> >    473 |         struct mgb4_regs *video;
> >        |                           ^~~~~
>
> checkpatch.pl --strict also gives a lot of warnings.
>
> You can ignore the "line length of 131 exceeds 100 columns" warnings for the hex dump.
> Those are OK in that particular case.
>
> But the suggested renamings would be good to implement to be consistent with other
> drivers.
>
> Regarding these:
>
> WARNING: Missing a blank line after declarations
> #3340: FILE: drivers/media/pci/mgb4/mgb4_trigger.c:93:
> +               u32 data;
> +               s64 ts __aligned(8);
>
> WARNING: externs should be avoided in .c files
> #3340: FILE: drivers/media/pci/mgb4/mgb4_trigger.c:93:
> +               s64 ts __aligned(8);
>
> This seems to be standard iio coding style, even though checkpatch
> gets confused by this. So let's leave this as-is.
>
> Regards,
>
> 	Hans

Hi Hans,
I'm out of office till next week so I'm not able to re-check it now, but 
there were generally three kinds of warnings from checkpatch:

1.) line lengths in the tables
2.) the iio code style
3.) the rename suggestions

I'm glad you have no problem with 1 and 2 as the current implementation 
makes IMHO more sense than following some strict automatic rules. The 
renaming makes not much sense either for me, but I can rename the 
functions if required. I will have a look at it when I'm back at work.

M.