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

Mauro Carvalho Chehab [off-list ref] wrote on Fri [2019-Aug-23 06:47:30 -0300]:

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

For:
drivers/media/platform/am437x/am437x-vpfe_regs.h
drivers/media/platform/ti-vpe/vpe_regs.h

Reviewed-by: Benoit Parrot <redacted>

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