[i2c] [PATCH 1/1] I2C pxa fast mode (400khz) support

[Troy Kisky]

David Brownell wrote:
> On Thursday 10 July 2008, Ben Dooks wrote:
>> On Thu, Jul 03, 2008 at 10:00:36AM +0800, Eric Miao wrote:
>>> Jonathan Cameron wrote:
>>>> Add fast_mode option to i2c_pxa_platform_data and use it to set the ICR_FM bit
>>>> appropriately when i2c_pxa_reset is called. Parameter called fast_mode rather
>>>> than frequency as this driver is also used for the i2c_pxa_pwr bus which has
>>>> different normal and fast frequencies.
>>> Maybe we should convert that (as well as 'use_pio') to a bit field to save
>>> another byte.
>> I think use_pio and fast_mode could both be bits.
> 
> Or alternatively, "bool" ... which is usually a byte, and
> on ARM will let GCC eliminate a comparision instruction.
> Just load byte and branch on zero/nonzero, vs needing one
> more instruction.

Unfortunately, on ARM the LDR/LDRB instructions can not
update the condition codes.