[PATCH 2/3] spi: mediatek: Add spi bus for Mediatek MT8173

[leilk.liu@mediatek.com (leilk liu)]

Dear Mark,

Thanks for your reply.

On Tue, 2015-05-12 at 17:05 +0100, Mark Brown wrote:
> On Tue, May 12, 2015 at 08:39:16PM +0800, leilk liu wrote:
> > On Fri, 2015-05-08 at 18:53 +0100, Mark Brown wrote:
> > > On Fri, May 08, 2015 at 04:55:42PM +0800, leilk.liu at mediatek.com wrote:
> 
> > Could you tell me more details about "You should also be using the core
> > helpers for DMA mapping"?
> 
> Implement can_dma() - look for drivers providing that for examples.
> 

MTK spi hardware uses the dmaengine in spi controller. According to
datasheet, spi driver just need to enable dma register bit and write a
physical address to relevant dma address register, so I think it may be
complex while the driver supports can_dma.

> > > > +static const struct of_device_id mtk_spi_of_match[] = {
> > > > +	{ .compatible = "mediatek,mt6589-spi", .data = (void *)COMPAT_MT6589},
> > > > +	{ .compatible = "mediatek,mt8173-spi", .data = (void *)COMPAT_MT8173},
> > > > +	{}
> > > > +};
> > > > +MODULE_DEVICE_TABLE(of, mtk_spi_of_match);
> 
> > > There were three compatible strings listed in the DT binding but only
> > > two here.
> 
> > MT6589 and MT8135 is compatible; 
> > For MT8135 IC, it can use the follow way in dts to probe:
> >   compatible = "mediatek,mt8135-spi", 
> > 	       "mediatek,mt6589-spi";
> 
> > And I test it's ok on MT8135 platform. So I add struct of_device_id
> > mtk_spi_of_match like this in spi driver code.
> 
> You should list all the compatibles documented in the binding here, if
> some of them are the same just have them map to a single constant.