Re: [PATCH v2 2/2] spi: Force CS to be in inactive state after off-mode transition

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On Wed, Nov 10, 2010 at 9:41 AM, Gregory CLEMENT
<gregory.clement@xxxxxxxxxxxxxxxxxx> wrote:
> On 11/10/2010 04:57 PM, Grant Likely wrote:
>>
>> On Wed, Nov 10, 2010 at 11:32:59AM +0100, Gregory CLEMENT wrote:
>>>
>>> When SPI wake up from OFF mode, CS is in the wrong state: force it
>>> to the inactive state.
>>>
>>> During the system life, I monitored the CS behavior using a
>>> oscilloscope. I also activated debug in omap2_mcspi, so I saw when
>>> driver disable the clocks and restore context when device is not
>>> used.
>>> Each time the CS was in the correct state.
>>> It was only when system was put suspend to ram with off-mode
>>> activated that on resume the CS was in wrong state( ie activated).
>>
>> Sounds like a bug in the suspend/resume path of the spi_master, not
>> the spi_device.  Trying to work around it via the spi_device resume
>> path is the wrong approach.
>>
>
> OK it was not clear to me that spi_resume() and spi_suspend() were specifics
> to devices as these functions belong to a bus structure.
>
> So you suggest to use the suspend/resume functions of the platform_driver
> structure of omap2_mcspi_driver, right?

correct.

g.
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