[PATCH v2 0/7] Change snvs rtc and poweroff to use syscon add pwrkey driver

[Zhi Li]

On Wed, May 20, 2015 at 7:20 PM, Dmitry Torokhov
<dmitry.torokhov at gmail.com> wrote:
> On Wed, May 20, 2015 at 07:30:50PM +0100, Russell King - ARM Linux wrote:
>> On Wed, May 20, 2015 at 07:25:41PM +0100, Russell King - ARM Linux wrote:
>> > On Wed, May 20, 2015 at 09:58:51AM +0800, Shawn Guo wrote:
>> > > On Wed, May 20, 2015 at 01:04:35AM +0800, Frank.Li at freescale.com wrote:
>> > > > Frank Li (6):
>> > > >   arm: imx: power-off: change to syscon to access register
>> > > >   rtc: arm: imx: snvs: change use syscon to access register
>> > > >   Document: dt: fsl: snvs: change support syscon
>> > > >   arm: dts: imx: update snvs to use syscon access register
>> > > >   document: devicetree: input: imx: i.mx snvs power device tree bindings
>> > > >   arm: dts: imx6sx: enable snvs power key
>> > >
>> > > So, the series will break existing DTBs for RTC and poweroff, right?
>> > > If this is unavoidable, should we at least have some warning messages
>> > > telling users about his breakage?
>> >
>> > What's the justification for breaking existing DTBs?  Really, this is
>> > something we should strive to avoid, _and_ actually avoid by providing
>> > backwards compatibility.
>>
>> Looking at the RTC code, it would be pretty trivial to do.
>>
>> Rather than passing around struct regmap, pass around the private data
>> structure.
>>
>> Rename the regmap_* function calls to be private accessors.  Implement
>> a set of new accessors - if the private data has the regmap, use the
>> regmap API.  Otherwise, use the old method, and print a warning that an
>> old DT is being used.
>
> Or maybe have drivers create regmap themselves if they see old DTS and
> not bother with the 2 sets of accessors?

Does any dt node convert to regmap regardless if there are "syscon"
compatible string?

>
> Thanks.
>
> --
> Dmitry