Subject: [PATCH v3 3/3] spi: spi-davinci: convert to DMA engine API

From: [email-masked] (Sekhar Nori)
Date: Fri, 31 Aug 2012 21:32:18 +0530

Hi Matt,

On 8/30/2012 8:13 PM, Matt Porter wrote:
> On Thu, Aug 30, 2012 at 07:46:32PM +0530, Sekhar Nori wrote:
>> Hi Matt,
>>
>> On 8/23/2012 6:39 AM, Matt Porter wrote:
>>> Removes use of the DaVinci EDMA private DMA API and replaces
>>> it with use of the DMA engine API.
>>>
>>> Signed-off-by: Matt Porter <[email-masked]>
>>
>> I tried testing this patch on my OMAP-L138 EVM, but SPI fails to 
>> initialize after applying the patch.
>>
>> root at arago:~# dmesg | grep -i spi                                               
>> spi_davinci spi_davinci.1: request RX DMA channel failed                        
> 
> Hi Sekhar,
> 
> Most likely CONFIG_TI_EDMA is off as it defaults to off in the v3
> series. Try enabling this and if it's the problem then this error
> path can be fixed to properly fallback to PIO only or fail to
> initialize as needed.

Yes, this was the problem. Since the SPI driver now depends on
CONFIG_TI_EDMA for basic operation may be select CONFIG_TI_EDMA in
Kconfig if SPI is enabled? That should do until the fallback to PIO is
implemented.

With that fixed, I tested SPI on OMAP-L138 EVM and it works great.
Tested a JFFS2 mount as well as some raw chardev read/write tests.

Tested-by: Sekhar Nori <[email-masked]>

Thanks,
Sekhar