[PATCH] spi: s3c64xx: add support for exynos7 SPI controller

Padma Venkat padma.kvr at gmail.com
Thu Nov 20 23:08:38 PST 2014


Hi Mark,

>>>> CS can also be controlled automatically by setting AUTO_N_MANUAL to 1
>>>> in CS_CFG. When it is auto CS automatically toggles between packet to
>>>> packet. NCS_TIME_COUNT in CS_CFG controls the inactive period. The
>>>> driver by default uses manual mode. But on exynos7 the manual mode is
>>>> removed.
>>>
>>> OK, but what's a packet here?
>>
>> Packet is either 1 byte or 4 bytes size depends on width of the SPI
>> channel.
>>
>>>
>>>> I tested the driver with wm5110 codec.
>>>
>>> Did you try firmware downloads or something else that generates multiple
>>> transfers in a message?  Normal register writes will use a single
>>> transfer so I'd expect them to just work.
>>>
>>
>> OK. I don't have provision to test on this board. I will try to test
>> on older boards by disabling manual mode.
>>
>
> I tested on exynos5420 peach-pit by enabling auto mode. I used dd
> command to read 1MB data from spi flash and I compared the result with
> manual mode. Both are same.

I also tested this patch with Javier Martinez Canillas patches for
enabling spidev nodes from
http://www.spinics.net/lists/linux-samsung-soc/msg39057.html.

I read 4MB flashdata from spi by enabling auto mode and compared the
result. They look same.

>
>> Thanks
>> padma
>>
>



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