[GIT PULL] ARM: SoC fixes for 3.12-rc

Brian Norris computersforpeace at gmail.com
Fri Sep 27 13:40:34 EDT 2013


On Fri, Sep 27, 2013 at 3:59 AM, Woodhouse, David
<david.woodhouse at intel.com> wrote:
> On Thu, 2013-09-19 at 17:44 -0700, Brian Norris wrote:
>> > Does that m25p80 'fix 4 byte addressing' fix for Micron not also want to
>> > go in?
>>
>> I suppose the m25p80 one can go in as well. It's not so much a bugfix
>> as augmenting my original patch to support more devices. But it is
>> safe enough.
>
> You say 'support more devices', but AFAICT the code in -rc1 will already
> *attempt* to enable 4-byte addressing on those devices, and fail.

As will the code in every release since 3.7-rc1 (commit
8da28681eb1430fb6715c7aef67001acfbbbcba5).

> (It looks like set_4byte() can return failure, but its return code isn't
> checked, and anyway it's only a SPI write so there's no feedback from
> the *chip* if it fails due to lack of WREN; it can only indicate failure
> if the SPI connection falls over.)
>
> So I'm inclined to think of it as a bug fix and include it.

Sure, it's a bug fix. Just a long-standing bug. We were sending
invalid commands to Micron devices, so no n25q256a devices could have
possibly been supported properly before the 3.12-rc cycle [*]. I'm not
sure who actually tested these flash way back in 3.7. I still would
qualify them as "new devices" for 3.12, but that's just semantics now.
Please, do include it.

Brian

[*] Under special circumstances they could have been supported. For
instance, some n25q256a packages defaulted to 4-byte addressing mode.



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