RE: [PATCH 01/30] staging: comedi: add pci_dev pointer to comedi_device

[H Hartley Sweeten <hartleys@visionengravers.com>]

On Monday, July 16, 2012 6:52 PM, Greg KH wrote:
> On Wed, Jul 11, 2012 at 02:49:14PM -0700, H Hartley Sweeten wrote:
>> The pci_dev pointer in the private driver data is used by every
>> comedi pci driver. Some of them only have the need for the
>> private data because of this pointer.
>> 
>> Introduce the pci_dev pointer in the comedi_device struct so it
>> can be used instead of needing it in the private data.
>> 
>> Signed-off-by: H Hartley Sweeten <hsweeten@visionengravers.com>
>> Cc: Ian Abbott <abbotti@mev.co.uk>
>> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
>> ---
>>  drivers/staging/comedi/comedidev.h | 2 ++
>>  1 file changed, 2 insertions(+)
>> 
>> diff --git a/drivers/staging/comedi/comedidev.h b/drivers/staging/comedi/comedidev.h
>> index de8c99c..55f2373 100644
>> --- a/drivers/staging/comedi/comedidev.h
>> +++ b/drivers/staging/comedi/comedidev.h
>> @@ -212,6 +212,8 @@ struct comedi_device {
>>  	 * DMA_NONE */
>>  	struct device *hw_dev;
>>  
>> +	struct pci_dev *pcidev;
>
> No, the field above this, hw_dev, should be used instead here, as that's
> what it is there for, right?

The hw_dev pointer is currently only used for something dealing with dma.
I have not dug into it yet to see what exactly it's used for.  The comment
says:

	/* hw_dev is passed to dma_alloc_coherent when allocating async buffers
	 * for subdevices that have async_dma_dir set to something other than
	 * DMA_NONE */

> Care to rework this series with that change instead?

It could probably be used with some sort of container_of but I'm not sure.

Regards,
Hartley