Re: [PATCH v10 03/10] media: platform: Add Renesas CEU driver

[Hans Verkuil <hverkuil@xs4all.nl>]

On 02/21/18 18:47, Jacopo Mondi wrote:
> Add driver for Renesas Capture Engine Unit (CEU).
> 
> The CEU interface supports capturing 'data' (YUV422) and 'images'
> (NV[12|21|16|61]).
> 
> This driver aims to replace the soc_camera-based sh_mobile_ceu one.
> 
> Tested with ov7670 camera sensor, providing YUYV_2X8 data on Renesas RZ
> platform GR-Peach.
> 
> Tested with ov7725 camera sensor on SH4 platform Migo-R.
> 
> Signed-off-by: Jacopo Mondi <jacopo+renesas@jmondi.org>
> Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>

I get these warnings when I try to compile this driver:


  CC [M]  drivers/media/platform/renesas-ceu.o
drivers/media/platform/renesas-ceu.c: In function ‘ceu_start_streaming’:
drivers/media/platform/renesas-ceu.c:290:2: warning: ‘cdwdr’ may be used uninitialized in this function [-Wmaybe-uninitialized]
  iowrite32(data, priv->base + reg_offs);
  ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
drivers/media/platform/renesas-ceu.c:338:27: note: ‘cdwdr’ was declared here
  u32 camcr, cdocr, cfzsr, cdwdr, capwr;
                           ^~~~~
drivers/media/platform/renesas-ceu.c:290:2: warning: ‘cfzsr’ may be used uninitialized in this function [-Wmaybe-uninitialized]
  iowrite32(data, priv->base + reg_offs);
  ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
drivers/media/platform/renesas-ceu.c:338:20: note: ‘cfzsr’ was declared here
  u32 camcr, cdocr, cfzsr, cdwdr, capwr;
                    ^~~~~
drivers/media/platform/renesas-ceu.c:418:8: warning: ‘camcr’ may be used uninitialized in this function [-Wmaybe-uninitialized]
  camcr |= mbus_flags & V4L2_MBUS_HSYNC_ACTIVE_LOW ? 1 << 0 : 0;
  ~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
drivers/media/platform/renesas-ceu.c:338:6: note: ‘camcr’ was declared here
  u32 camcr, cdocr, cfzsr, cdwdr, capwr;
      ^~~~~
drivers/media/platform/renesas-ceu.c: In function ‘ceu_probe’:
drivers/media/platform/renesas-ceu.c:1632:9: warning: ‘ret’ may be used uninitialized in this function [-Wmaybe-uninitialized]
  return ret;
         ^~~
cc1: some warnings being treated as errors

The last warning is indeed correct.

The others are only right if pixelformat is illegal, which can't happen.
I'd add a:

	default:
		return -EINVAL;

to the switch, this shuts up the warnings.

So I need a v11 (just for this patch) after all.

Regards,

	Hans