[PATCH 1/5] spi/mxs: Fix extra CS pulses and read mode in multi-transfer messages

Marek Vasut marex at denx.de
Tue Apr 2 19:39:32 EDT 2013


Dear Trent Piepho,

> On Tue, Apr 2, 2013 at 3:32 AM, Marek Vasut <marex at denx.de> wrote:
> >> Don't see anything in CodingStyle that one should be preferred over
> >> the other.
> > 
> > There ain't any I'm aware of, but to paraphrase you, let's keep the
> > format that's already used in the driver ;-) :
> > 
> > 114         if (dev->mode & ~(SPI_CPOL | SPI_CPHA))
> 
> Thanks for pointing that out, as that code can be deleted.  Which
> means I don't need to be consistent with it anymore and can create a
> new standard, to be followed henceforth, now and forever.
> 
> But it looks like the or method is more common in the kernel code.  So
> I'll change it in V2.
> 
> >> > btw. are you using MX23 or MX28 to test this?
> >> 
> >> IMX28.
> > 
> > Is that any mainline board?
> 
> Nope, custom hardware.
> 
> >> >> Existing code that uses the first/last flags is wrong and needs to be
> >> >> changed.  Therefor code using 'first' and 'last' will be changed.
> >> >> 
> >> >> Passing the flags as pointers is bad practice and makes no sense to
> >> >> do.  Does it make any sense to re-write code fix the way it uses
> >> >> first and last, then re-write those same lines a second time to not
> >> >> use pointers?
> >> > 
> >> > You can always flip it the other way -- first rework the use of flags,
> >> > then apply the fix. It'd make the patch much easier to understand,
> >> > don't you think?
> >> 
> >> So I should change 'first' to not be a pointer to an integer in one
> >> patch, then delete the flag entirely in another patch?
> > 
> > I'd say make a patch (0001) that implements the transition to using your
> > newly defined flags and then make a patch (0002) that "Fix extra CS
> > pulses and read mode in multi-transfer messages". One patch shall do one
> > thing, that's the usual rule of the thumb. Obviously keep them in a
> > series if these patches shall go in together. And why doesn't squashing
> > them all together work you might ask -- because reviewing the result is
> > hard.
> 
> 5 patches have now been split into 12.

Much better, yes.

Best regards,
Marek Vasut



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