lkml.org 
[lkml]   [2018]   [Jul]   [5]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
From
SubjectRe: [PATCH 02/14] dmaengine: dma-jz4780: Separate chan/ctrl registers
Hi Paul,

> Hi Paul,
>
> On Tue, Jul 03, 2018 at 02:32:02PM +0200, Paul Cercueil wrote:
>> @@ -804,9 +818,19 @@ static int jz4780_dma_probe(struct
>> platform_device *pdev)
>> return -EINVAL;
>> }
>>
>> - jzdma->base = devm_ioremap_resource(dev, res);
>> - if (IS_ERR(jzdma->base))
>> - return PTR_ERR(jzdma->base);
>> + jzdma->chn_base = devm_ioremap_resource(dev, res);
>> + if (IS_ERR(jzdma->chn_base))
>> + return PTR_ERR(jzdma->chn_base);
>> +
>> + res = platform_get_resource(pdev, IORESOURCE_MEM, 1);
>> + if (!res) {
>> + dev_err(dev, "failed to get I/O memory\n");
>> + return -EINVAL;
>> + }
>> +
>> + jzdma->ctrl_base = devm_ioremap_resource(dev, res);
>> + if (IS_ERR(jzdma->ctrl_base))
>> + return PTR_ERR(jzdma->ctrl_base);
>
> Could we have this failure case fall back to the existing behaviour
> where we only have a single resource covering all the registers? That
> would avoid breaking bisection between this patch & the one that
> updates
> the JZ4780 DT.
>
> For example:
>
> #define JZ4780_DMA_CTRL_OFFSET 0x1000
>
> res = platform_get_resource(pdev, IORESOURCE_MEM, 1);
> if (res) {
> jzdma->ctrl_base = devm_ioremap_resource(dev, res);
> if (IS_ERR(jzdma->ctrl_base))
> return PTR_ERR(jzdma->ctrl_base);
> } else {
> jzdma->ctrl_base = jzdma->chn_base + JZ4780_DMA_CTRL_OFFSET;
> }
>
> Then you could remove the fallback after patch 13, to end up with the
> same code you have now but without breaking bisection.
>
> Most correct might be to move patch 13 to right after this one, so
> that
> the JZ4780-specific fallback can be removed before adding support for
> any of the other SoCs.

Sure, I can do that for the V2.

Thanks,
-Paul

\
 
 \ /
  Last update: 2018-07-05 20:24    [W:0.314 / U:2.580 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site