[U-Boot] [PATCH 1/2] mmc: add bcm2835 driver

[Albert ARIBAUD]

Hi Stephen,

On Sun, 28 Oct 2012 22:36:25 +0530, Vikram Narayanan
<vikram186 at gmail.com> wrote:

> On 10/28/2012 8:58 AM, Stephen Warren wrote:
> > On 10/26/2012 05:33 AM, Vikram Narayanan wrote:
> >> Some nitpicks.
> >>
> >> On 10/24/2012 10:20 AM, Stephen Warren wrote:
> <snip>
> >>> +static u8 bcm2835_sdhci_readb(struct sdhci_host *host, int reg)
> >>> +{
> >>> +    u32 val = bcm2835_sdhci_raw_readl(host, (reg&   ~3));
> >>> +    val = val>>   (reg<<   3&   0x18)&   0xff;
> >>> +
> >>> +    return (u8)val;
> >>> +}
> >>
> >> Can the above used magics be made as macros?
> >
> > This code was taken directly from the downstream Linux kernel, so I
> > changed it as little as possible, to make comparisons easier. Still, if
> > people want I can certainly make it easier to understand the expression
> > a bit.
> 
> Seems reasonable.
> 
> > I don't think the issue is the magic numbers so much as understanding
> > what the expression does; the magic are obvious then. It's simply
> > extracting byte n from from a u32. Would the following be more obvious:
> >
> > byte_num = reg&  3;
> > byte_shift = bytenum * 8;
> > byte = (val>>  byte_shift)&  0xff;
> >
> > ... and similar for the other functions?
> 
> This looks better to me than the former. Thanks.

Stephen,

Does this mean there'll be a new version of this patch?

Amicalement,
-- 
Albert.