[U-Boot] [PATCH v2 1/2] linux/bitops.h: Add BIT macro

[Simon Glass]

Hi Jagan,

On 29 April 2015 at 08:58, Jagan Teki <jagannadh.teki at gmail.com> wrote:
> Hi Simon,
>
> On 29 April 2015 at 20:12, Simon Glass <sjg at chromium.org> wrote:
>> Hi Tom,
>>
>> On 29 April 2015 at 07:08, Tom Rini <trini at konsulko.com> wrote:
>>> On Wed, Apr 29, 2015 at 05:35:05PM +0530, Jagannadha Sutradharudu Teki wrote:
>>>
>>>> Replace (1 << nr) to BIT(nr) where nr = 0, 1, 2 .... 31
>>>>
>>>> Signed-off-by: Jagannadha Sutradharudu Teki <jagannadh.teki at gmail.com>
>>>> Cc: Masahiro Yamada <yamada.m at jp.panasonic.com>
>>>> Cc: Tom Rini <trini at konsulko.com>
>>>> Cc: Simon Glass <sjg at chromium.org>
>>>
>>> I think that conceptually this is a good idea.  We need to apply this
>>> fairly quickly however as it already throws out a few rejects with the
>>> PRs I've taken and doing some local testing on.
>>
>> We have to date avoided this (I've been here before). But I think it
>> is useful. One concern I have is misuse, when someone does BIT(0) |
>> BIT(1))| BIT(2) | BIT(3) instead of 0xf, for example.
>
> Probably we can achieve this with GENMASK(h, l), may be we can add that also?

I'm not sure about that...we might end up with this:

http://patchwork.ozlabs.org/patch/93363/

Regards,
Simon