Re: [PATCH v6 1/2] spi: Add spi driver for Sunplus SP7021

From: Andy Shevchenko
Date: Thu Jan 20 2022 - 04:52:11 EST


On Thu, Jan 20, 2022 at 11:22 AM Lh Kuo 郭力豪 <lh.Kuo@xxxxxxxxxxx> wrote:

...

> > > + if (xfer->tx_buf)
> > > + dma_unmap_single(dev, xfer->tx_dma, xfer->len, DMA_TO_DEVICE);
> > > + if (xfer->rx_buf)
> > > + dma_unmap_single(dev, xfer->rx_dma, xfer->len,
> > > + DMA_FROM_DEVICE);
> >
> > Why can't you use SPI core DMA mapping code?
>
> I didn't find the SPI core DMA mapping code for single maping.
> The method currently used is the general DMA single-map code usage method.

Why do you need single page mapping?
What's wrong with SG mapping that SPI core provides?

...

> > > + device_set_node(&ctlr->dev, pdev->dev.fwnode);
> >
> > Use dev_fwnode() in the second argument.
>
> You mean as below ?
>
> device_set_node(&ctlr->dev, dev_fwnode(dev));

Yes.

--
With Best Regards,
Andy Shevchenko