Message-ID: <1431675522.2128.13.camel@mhfsdcap03>
Subject: Re: [PATCH 2/3] spi: mediatek: Add spi bus for Mediatek MT8173
From: leilk liu <leilk.liu@mediatek.com>
To: Mark Brown <broonie@kernel.org>
CC: Mark Rutland <mark.rutland@arm.com>,
        Matthias Brugger <matthias.bgg@gmail.com>,
        Rob Herring <robh+dt@kernel.org>, Pawel Moll <pawel.moll@arm.com>,
        Ian Campbell <ijc+devicetree@hellion.org.uk>,
        "Kumar Gala" <galak@codeaurora.org>,
        Catalin Marinas <catalin.marinas@arm.com>,
        Will Deacon <will.deacon@arm.com>,
        Eddie Huang <eddie.huang@mediatek.com>,
        Hongzhou Yang <hongzhou.yang@mediatek.com>,
        Sascha Hauer <s.hauer@pengutronix.de>, <devicetree@vger.kernel.org>,
        <linux-kernel@vger.kernel.org>, <linux-arm-kernel@lists.infradead.org>,
        <linux-spi@vger.kernel.org>, <linux-mediatek@lists.infradead.org>,
        <srv_heupstream@mediatek.com>, Sascha Hauer <kernel@pengutronix.de>,
        <leilk.liu@mediatek.com>
Date: Fri, 15 May 2015 15:38:42 +0800
In-Reply-To: <20150512160540.GB3066@sirena.org.uk>
References: <1431075343-7887-1-git-send-email-leilk.liu@mediatek.com>
	 <1431075343-7887-3-git-send-email-leilk.liu@mediatek.com>
	 <20150508175306.GG2761@sirena.org.uk> <1431434356.2128.9.camel@mhfsdcap03>
	 <20150512160540.GB3066@sirena.org.uk>
Content-Type: text/plain; charset="UTF-8"
Content-Transfer-Encoding: 7bit
MIME-Version: 1.0
Sender: linux-kernel-owner@vger.kernel.org
Content-Length: 1824
Lines: 47

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@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.


--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/