Re: [PATCH 4/7] spi: spi-geni-qcom: Add support for GPI dma

From: Vinod Koul
Date: Wed Jun 16 2021 - 04:50:53 EST


Hi Mark,

On 11-01-21, 16:35, Mark Brown wrote:
> On Mon, Jan 11, 2021 at 08:46:48PM +0530, Vinod Koul wrote:
>
> > +static int get_xfer_mode(struct spi_master *spi)
> > +{
> > + struct spi_geni_master *mas = spi_master_get_devdata(spi);
> > + struct geni_se *se = &mas->se;
> > + int mode = GENI_SE_FIFO;
>
> Why not use the core DMA mapping support?

Sorry I seemed to have missed replying to this one.

Looking at the code, that is ideal case. Only issue I can see is that
core DMA mapping device being used is incorrect. The core would use
ctlr->dev.parent which is the spi0 device here.

But in this case, that wont work. We have a parent qup device which is
the parent for both spi and dma device and needs to be used for
dma-mapping!

If we allow drivers to set dma mapping device and use that, then I can
reuse the core. Let me know if that is agreeable to you and I can hack
this up. Maybe add a new member in spi_controller which is filled by
drivers in can_dma() callback?

Thanks
--
~Vinod