Subject: [PATCH v3 05/11] memory: add Atmel EBI (External Bus Interface) driver

From: [email-masked] (Boris Brezillon)
Date: Mon, 15 Dec 2014 11:43:38 +0100

On Mon, 15 Dec 2014 11:29:14 +0100
Alexander Stein <[email-masked]> wrote:

> On Monday 15 December 2014 11:22:30, Boris Brezillon wrote:
> > Hi Alexander,
> > 
> > On Tue, 09 Dec 2014 21:53:12 +0100
> > Alexander Stein <[email-masked]> wrote:
> > 
> > > Hi,
> > > 
> > > On Monday 01 December 2014, 11:27:21 wrote Boris Brezillon:
> > > > +static int at91_ebi_probe(struct platform_device *pdev)
> > > > +{
> > > > +	const struct of_device_id *match;
> > > > +	struct device_node *child;
> > > > +	struct device_node *np;
> > > > +	struct at91_ebi *ebi;
> > > > +	struct clk *clk;
> > > > +	int ret;
> > > > +
> > > > +	match = of_match_device(at91_ebi_id_table, &pdev->dev);
> > > > +	if (!match || !match->data)
> > > > +		return -EINVAL;
> > > > +
> > > > +	ebi = devm_kzalloc(&pdev->dev, sizeof(*ebi), GFP_KERNEL);
> > > > +	if (!ebi)
> > > > +		return -ENOMEM;
> > > > +
> > > > +	ebi->caps = match->data;
> > > > +	ebi->dev = &pdev->dev;
> > > > +
> > > > +	clk = devm_clk_get(&pdev->dev, NULL);
> > > > +	if (IS_ERR(clk))
> > > > +		return PTR_ERR(clk);
> > > > +
> > > > +	ebi->clk = clk;
> > > > +
> > > > +	np = of_parse_phandle(pdev->dev.of_node, "atmel,smc", 0);
> > > > +	if (!np)
> > > > +		return -EINVAL;
> > > > +
> > > > +	ebi->smc = syscon_node_to_regmap(np);
> > > > +	if (IS_ERR(ebi->smc))
> > > > +		return PTR_ERR(ebi->smc);
> > > > +
> > > > +	/*
> > > > +	 * The sama5d3 does not provide an EBICSA register and thus does need
> > > > +	 * to access the matrix registers.
> > > > +	 */
> > > > +	if (ebi->caps->ebi_csa) {
> > > > +		np = of_parse_phandle(pdev->dev.of_node, "atmel,matrix", 0);
> > > > +		if (np)
> > >          ^^^^^^^
> > > Shouldn't this be if (!np)?
> > 
> > Absolutely, thanks for pointing this out.
> > I'll test on other at91 platforms (I currently only test on sama5d3
> > boards, which do not have this EBICSA register) before submitting a new
> > version.
> 
> Oh, well. I've noticed you posted a v4 of this patch which changed this specific code. I didn't noticed this.

Indeed, calling syscon_regmap_lookup_by_phandle fixed the problem.

Actually there is a v5 [1], and you should use this version because the
DT binding has slightly changed).
I'll add you in Cc of my future versions ;-).

> I'll replace the old v3 and retry. I'm using this code on 9263 so far configuring EBI1 for a PSRAM. Works so far.
> Once I exchanged patch 05/11 with your v4 I'll send my DT changes for 9263 to support this feature.

Thanks for testing that part, I'm looking forward to your DT
patches :-).

Regards,

Boris

[1]https://lkml.org/lkml/2014/12/3/806

-- 
Boris Brezillon, Free Electrons
Embedded Linux and Kernel engineering
http://free-electrons.com