lkml.org 
[lkml]   [2017]   [Nov]   [8]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
From
SubjectRe: [PATCH] rtc: omap: Support scratch registers
On 08/11/2017 at 12:38:05 +0530, Keerthy wrote:
>
>
> On Wednesday 08 November 2017 11:57 AM, Alexandre Belloni wrote:
> > Hi,
> >
> > On 08/11/2017 at 11:30:45 +0530, Keerthy wrote:
> >>>>> +static int omap_rtc_scratch_read(void *priv, unsigned int offset, void *_val,
> >>>>> + size_t bytes)
> >>>>> +{
> >>>>> + struct omap_rtc *rtc = priv;
> >>>>> + u32 *val = _val;
> >>>>> + int i;
> >>>>> +
> >>>>> + for (i = 0; i < bytes / 4; i++)
> >>>>> + val[i] = rtc_readl(rtc,
> >>>>> + OMAP_RTC_SCRATCH0_REG + offset + (i * 4));
> >>
> >> Can the offset be the Scratch register number instead of bytes offset?
> >> More intuitive to me.
> >>
> >> So that one can request using offset as 0, 1, 2 instead of 0, 4, 8?
> >>
> >
> > Well, the offset is coming from the nvmem core, itself getting it from
> > the Linux file API (and it is in bytes). However, you have the guarantee
> > that it will be aligned on a word, see:
> > http://elixir.free-electrons.com/linux/latest/source/drivers/nvmem/core.c#L88
>
> Okay Alexandre. Thanks for clarifying. Looks good to me.
> I have tested on AM437X-GP-EVM.
>

If needed, you can define nvmem cells (and I guess that is what you
want):
http://elixir.free-electrons.com/linux/latest/source/Documentation/devicetree/bindings/nvmem/nvmem.txt


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

\
 
 \ /
  Last update: 2017-11-08 21:10    [W:0.051 / U:0.028 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site