kernel panic in spi_complete() on spitz (PXA270)

Igor Grinberg grinberg at
Thu Jun 30 16:50:17 EDT 2011

On 06/30/11 21:01, Mark Brown wrote:
> On Thu, Jun 30, 2011 at 08:40:40PM +0300, Igor Grinberg wrote:
>> On 06/30/11 19:13, Stanislav Brabec wrote:
>>>  I seen two
>>> proposals:
>>> - As ADS7846 hardware does not require dedicated regulator, don't
>>>   require it in driver and fail only on platforms that have a dedicated
>>>   regulator.
>> The thing is that ads7846 chip itself just requires power supply
> Right, and the regulator API hides the non-switchability of the supply
> from the driver so there's no need for the driver to worry about how the
> supplies are wired up.  It just turns the regulator on when it needs it
> and turns it off when it doesn't.
>>>> 1) add regulator definition for ads7846 into the board file
>>> There is no dedicated regulator on spitz, ADS7846 uses common always-on
>>> power supply.
>> Is there a kind of regulator for this case (except dummy)?
>> Some kind of fixed regulator which is not binded to any supply?
> This is just a fixed voltage regulator, support for that has been in the
> kernel since the regulator API was merged.  This is the best solution,
> it ensures that you don't mistakenly activate dummy reglators for
> supplies that really need software control.

Right, just as I thought (I still haven't made myself familiar with all the
regulator API aspects).

Can't you define a fixed voltage regulator for the ads7846 in spitz board file?
This shouldn't be a hard task and is the right solution from the regulator API POV.


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