Re: [PATCH v2 6/7] dmaengine: fsl-edma: add i.mx7ulp edma2 version support

[Vinod Koul <vkoul@kernel.org>]

On 27-05-19, 11:05, Sascha Hauer wrote:
> On Mon, May 27, 2019 at 04:51:17PM +0800, yibin.gong@nxp.com wrote:
> > From: Robin Gong <yibin.gong@nxp.com>
> > 
> > +static const struct of_device_id fsl_edma_dt_ids[] = {
> > +	{ .compatible = "fsl,vf610-edma", .data = (void *)v1 },
> > +	{ .compatible = "fsl,imx7ulp-edma", .data = (void *)v3 },
> > +	{ /* sentinel */ }
> 
> Please put a struct type behind the .data pointer so that you can
> configure...

Yeah that was the idea behind the suggestion in previous version.

Something like 

struct fsl_edma_driver_data {
        unsigned int channels;
        ...
};

and then you have

const struct fsl_edma_driver_data v1_data {
        .channels = 1;
        ...
};

> 
> > +};
> > +MODULE_DEVICE_TABLE(of, fsl_edma_dt_ids);
> > +
> > @@ -218,6 +272,22 @@ static int fsl_edma_probe(struct platform_device *pdev)
> >  	fsl_edma_setup_regs(fsl_edma);
> >  	regs = &fsl_edma->regs;
> >  
> > +	if (fsl_edma->version == v3) {
> > +		fsl_edma->dmamux_nr = 1;

You can store the struct in driver context or store the values, so here
it becomes

        driver->data->channel;

and so on for other data, you can also point function pointers (hint
edma/2_irq_init)

> 
> ...things like this...
> 
> > @@ -264,7 +334,11 @@ static int fsl_edma_probe(struct platform_device *pdev)
> >  	}
> >  
> >  	edma_writel(fsl_edma, ~0, regs->intl);
> > -	ret = fsl_edma_irq_init(pdev, fsl_edma);
> > +
> > +	if (fsl_edma->version == v3)
> > +		ret = fsl_edma2_irq_init(pdev, fsl_edma);
> > +	else
> > +		ret = fsl_edma_irq_init(pdev, fsl_edma);
> 
> ...and this one in that struct rather than littering the code more and
> more with such version tests.
> 
> Sascha
> 
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-- 
~Vinod