Re: [PATCH v3 5/5] mtd: spi-nor: cadence-quadspi: Add runtime PM support
From: Vignesh R
Date: Sun Sep 24 2017 - 09:28:42 EST
On 9/24/2017 6:42 PM, Marek Vasut wrote:
> On 09/24/2017 03:08 PM, Vignesh R wrote:
>>
>>
>> On 9/24/2017 5:31 PM, Marek Vasut wrote:
>>> On 09/24/2017 12:59 PM, Vignesh R wrote:
>>>> Add pm_runtime* calls to cadence-quadspi driver. This is required to
>>>> switch on QSPI power domain on TI 66AK2G SoC during probe.
>>>>
>>>> Signed-off-by: Vignesh R <vigneshr@xxxxxx>
>>>
>>> Are you planning to add some more fine-grained PM control later?
>>
>> Yes, I will need to add fine-grained PM control at some point. But, for
>> now SoC does not really support low power mode or runtime power saving
>> option.
>> The fact that driver still uses clk_prepare_*() calls to enable/disable
>> clocks instead of pm_*() calls makes it a bit tricky though.
>>
>> Just figured out I forgot to add cleanup code in error handling path of
>> probe(). Will fix that and send a v4.
>
> OK, fine. Cleanups are welcome. The SoCFPGA doesn't do much runtime PM
> either, so it's fine for now.
>
Ok thanks! Do you know if pm_runtime_get_sync() can enable clocks for
QSPI on SoCFPGA or if clk_prepare_enable() is needed? Just trying to see
if its possible to get rid of clk_*() calls in favor of pm_*() calls.