Re: [PATCH v2 5/7] media: use the BIT() macro

From: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
To: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
Cc: Kate Stewart <kstewart@linuxfoundation.org>,
	Richard Fontana <rfontana@redhat.com>,
	"Lad, Prabhakar" <prabhakar.csengg@gmail.com>,
	Thierry Reding <thierry.reding@gmail.com>,
	Bluecherry Maintainers <maintainers@bluecherrydvr.com>,
	Krzysztof Kozlowski <krzk@kernel.org>,
	Sylwester Nawrocki <s.nawrocki@samsung.com>,
	devel@driverdev.osuosl.org, linux-samsung-soc@vger.kernel.org,
	Michal Simek <michal.simek@xilinx.com>,
	Andrey Utkin <andrey.utkin@corp.bluecherry.net>,
	Jonathan Hunter <jonathanh@nvidia.com>,
	Kukjin Kim <kgene@kernel.org>,
	linux-arm-kernel@lists.infradead.org,
	Ismael Luceno <ismael@iodev.co.uk>,
	Linux Media Mailing List <linux-media@vger.kernel.org>,
	Mauro Carvalho Chehab <mchehab@infradead.org>,
	Benoit Parrot <bparrot@ti.com>,
	linux-tegra@vger.kernel.org, Thomas Gleixner <tglx@linutronix.de>,
	Anton Sviridenko <anton@corp.bluecherry.net>,
	Allison Randal <alliso>
Subject: Re: [PATCH v2 5/7] media: use the BIT() macro
Date: Fri, 23 Aug 2019 23:45:13 +0300	[thread overview]
Message-ID: <20190823204513.GF4791@pendragon.ideasonboard.com> (raw)
In-Reply-To: <d6c04bf604084af63fec603b4afbd72c648e0394.1566553525.git.mchehab+samsung@kernel.org>

Hi Mauro,

Thank you for the patch.

On Fri, Aug 23, 2019 at 06:47:30AM -0300, Mauro Carvalho Chehab wrote:
> As warned by cppcheck:
> 
> 	[drivers/media/dvb-frontends/cx24123.c:434]: (error) Shifting signed 32-bit value by 31 bits is undefined behaviour
> 	[drivers/media/pci/bt8xx/bttv-input.c:87]: (error) Shifting signed 32-bit value by 31 bits is undefined behaviour
> 	[drivers/media/pci/bt8xx/bttv-input.c:98]: (error) Shifting signed 32-bit value by 31 bits is undefined behaviour
> 			...
> 	[drivers/media/v4l2-core/v4l2-ioctl.c:1391]: (error) Shifting signed 32-bit value by 31 bits is undefined behaviour
> 
> There are lots of places where we're doing 1 << 31. That's bad,
> as, depending on the architecture, this has an undefined behavior.
> 
> The BIT() macro is already prepared to handle this, so, let's
> just switch all "1 << number" macros by BIT(number) at the header files
> with has 1 << 31.
> 
> Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
> ---
> 
> v2: 
>   As suggested by Laurent:
>      - Don't touch multi-bit masks
>      - remove explicit casts
> 
>  drivers/media/pci/cobalt/cobalt-driver.h      |  63 +-
>  drivers/media/pci/ivtv/ivtv-irq.h             |  28 +-
>  drivers/media/pci/mantis/mantis_reg.h         | 152 ++---
>  drivers/media/pci/solo6x10/solo6x10-regs.h    | 286 ++++-----
>  .../media/platform/am437x/am437x-vpfe_regs.h  |  26 +-
>  .../media/platform/davinci/dm644x_ccdc_regs.h |  20 +-
>  .../media/platform/exynos4-is/fimc-lite-reg.h |  80 +--
>  drivers/media/platform/exynos4-is/fimc-reg.h  | 138 +++--
>  drivers/media/platform/omap3isp/ispreg.h      | 580 +++++++++---------
>  drivers/media/platform/s3c-camif/camif-regs.h | 118 ++--
>  drivers/media/platform/tegra-cec/tegra_cec.h  |  80 +--
>  drivers/media/platform/ti-vpe/vpe_regs.h      |  94 +--
>  drivers/media/platform/vsp1/vsp1_regs.h       | 224 +++----
>  drivers/media/platform/xilinx/xilinx-vip.h    |  29 +-
>  drivers/media/radio/wl128x/fmdrv_common.h     |  88 +--
>  drivers/staging/media/ipu3/ipu3-tables.h      |   4 +-
>  16 files changed, 1011 insertions(+), 999 deletions(-)

[snip]

> diff --git a/drivers/media/platform/omap3isp/ispreg.h b/drivers/media/platform/omap3isp/ispreg.h
> index 38e2b99b3f10..4c6ebc0b74d1 100644
> --- a/drivers/media/platform/omap3isp/ispreg.h
> +++ b/drivers/media/platform/omap3isp/ispreg.h

[snip]

> @@ -1167,14 +1167,14 @@
>  #define ISPHIST_HV_INFO_MASK			0x3FFF3FFF
>  
>  #define ISPCCDC_LSC_ENABLE			1

This is a bit too, it could be replaced with BIT(0).

> -#define ISPCCDC_LSC_BUSY			(1 << 7)
> +#define ISPCCDC_LSC_BUSY			BIT(7)
>  #define ISPCCDC_LSC_GAIN_MODE_N_MASK		0x700
>  #define ISPCCDC_LSC_GAIN_MODE_N_SHIFT		8
>  #define ISPCCDC_LSC_GAIN_MODE_M_MASK		0x3800
>  #define ISPCCDC_LSC_GAIN_MODE_M_SHIFT		12
>  #define ISPCCDC_LSC_GAIN_FORMAT_MASK		0xE
>  #define ISPCCDC_LSC_GAIN_FORMAT_SHIFT		1
> -#define ISPCCDC_LSC_AFTER_REFORMATTER_MASK	(1<<6)
> +#define ISPCCDC_LSC_AFTER_REFORMATTER_MASK	BIT(6)
>  
>  #define ISPCCDC_LSC_INITIAL_X_MASK		0x3F
>  #define ISPCCDC_LSC_INITIAL_X_SHIFT		0

[snip]

With this small issue addressed,

For omap3isp, vsp1, xilinx, wl128x and ipu3,

Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>

-- 
Regards,

Laurent Pinchart