Re: [PATCH v7 04/14] spi: cadence: Provide a capability structure

[Pratyush Yadav <p.yadav@xxxxxx>]

On 21/12/21 11:16AM, Miquel Raynal wrote:
> Hi Pratyush,
> 
> p.yadav@xxxxxx wrote on Tue, 21 Dec 2021 00:25:18 +0530:
> 
> > > Subject: [PATCH v7 04/14] spi: cadence: Provide a capability structure  
> > 
> > s/cadence/cadence-quadspi/
> 
> Right.
> 
> > 
> > On 17/12/21 05:16PM, Miquel Raynal wrote:
> > > This controller has DTR support, so advertize it with a capability now
> > > that the spi_controller_mem_ops structure contains this new field. This
> > > will later be used by the core to discriminate whether an operation is
> > > supported or not, in a more generic way than having different helpers.
> > > 
> > > Signed-off-by: Miquel Raynal <miquel.raynal@xxxxxxxxxxx>
> > > ---
> > >  drivers/spi/spi-cadence-quadspi.c | 5 +++++
> > >  1 file changed, 5 insertions(+)
> > > 
> > > diff --git a/drivers/spi/spi-cadence-quadspi.c b/drivers/spi/spi-cadence-quadspi.c
> > > index 101cc71bffa7..98e0cc4236e3 100644
> > > --- a/drivers/spi/spi-cadence-quadspi.c
> > > +++ b/drivers/spi/spi-cadence-quadspi.c
> > > @@ -1388,10 +1388,15 @@ static const char *cqspi_get_name(struct spi_mem *mem)
> > >  	return devm_kasprintf(dev, GFP_KERNEL, "%s.%d", dev_name(dev), mem->spi->chip_select);
> > >  }
> > >  
> > > +static const struct spi_controller_mem_caps cqspi_mem_caps = {
> > > +	.dtr = true,
> > > +};
> > > +
> > >  static const struct spi_controller_mem_ops cqspi_mem_ops = {
> > >  	.exec_op = cqspi_exec_mem_op,
> > >  	.get_name = cqspi_get_name,
> > >  	.supports_op = cqspi_supports_mem_op,
> > > +	.caps = &cqspi_mem_caps,  
> > 
> > I just noticed you put it under struct spi_mem_ops, not under struct 
> > spi_mem. This is not an operation per se so wouldn't it be better if it 
> > is moved to struct spi_mem?
> 
> I had a hard time taking a decision but my conclusion was that these
> caps are static controller capabilities and exclusively tight to the
> controller. The spi_mem structure defines a SPI peripheral. The
> spi_mem_ops structure is the only spi-mem related field of the
> spi-controller structure. I could have added my own field there but
> as these caps are only meant to be used by the spi_mem_ops anyway
> (exclusively ->supports_op() for now), it seemed to be a good location,
> at least better than the spi-mem structure.

Can we have a 3rd person chime in and break the tie? :-)

> 
> > Anyway, the change itself looks good to me. The cqspi_supports_mem_op()
> > already checks for mixed DTR modes so we should be good.
> 
> Yep!
> 
> > 
> > >  };
> > >  
> > >  static int cqspi_setup_flash(struct cqspi_st *cqspi)
> > > -- 
> > > 2.27.0
> > >   
> > 
> 
> 
> Thanks,
> Miquèl

-- 
Regards,
Pratyush Yadav
Texas Instruments Inc.