RE: [PATCH] can: flexcan: Implement CAN Runtime PM

From: Joakim Zhang
Date: Wed Nov 21 2018 - 20:39:35 EST


Hi Marc,

Best Regards,
Joakim Zhang

> -----Original Message-----
> From: Marc Kleine-Budde <mkl@xxxxxxxxxxxxxx>
> Sent: 2018å11æ21æ 22:36
> To: Joakim Zhang <qiangqing.zhang@xxxxxxx>; wg@xxxxxxxxxxxxxx;
> davem@xxxxxxxxxxxxx
> Cc: linux-can@xxxxxxxxxxxxxxx; netdev@xxxxxxxxxxxxxxx;
> linux-kernel@xxxxxxxxxxxxxxx; dl-linux-imx <linux-imx@xxxxxxx>; Aisheng
> DONG <aisheng.dong@xxxxxxx>
> Subject: Re: [PATCH] can: flexcan: Implement CAN Runtime PM
>
> On 10/19/18 11:45 AM, Joakim Zhang wrote:
> > From: Dong Aisheng <aisheng.dong@xxxxxxx>
> >
> > Flexcan will be disabled during suspend if no wakeup function required
> > and enabled after resume accordingly. During this period, we could
> > explicitly disable clocks.
> >
> > Implement Runtime PM which will:
> > 1) Keep device in suspend state (clocks disabled) if it's not openned
> > 2) Make Power Domain framework be able to shutdown the corresponding
> > power domain of this device.
>
> Without CONFIG_PM the device fails to probe:
>
> > [ 214.420606] flexcan 2090000.flexcan: 2090000.flexcan supply xceiver
> > not found, using dummy regulator [ 214.445952] flexcan
> > 2090000.flexcan: Linked as a consumer to regulator.0 [ 214.453448]
> > flexcan 2090000.flexcan: registering netdev failed [ 214.459666]
> > flexcan 2090000.flexcan: Dropping the link to regulator.0 [
> > 214.472066] flexcan: probe of 2090000.flexcan failed with error -110

I will firstly send the patch to do FlexCAN wakeup upstream, you could review the patch "can: flexcan: add self wakeup support" when you are free.
After you have reviewed, then I will send patch to do FlexCAN runtime PM upstream. It will be convenient for you to review the patch.

Thanks a lot for your review.

Best Regards,
Joakim Zhang

> Marc
>
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