Re: [PATCH] i2c: enable async suspend/resume on i2c devices

From: dbasehore .
Date: Fri Jul 27 2018 - 12:17:27 EST




On Fri, Jul 27, 2018 at 5:07 AM Hans de Goede <hdegoede@xxxxxxxxxx> wrote:
Hi,

On 07/27/2018 12:44 PM, Andy Shevchenko wrote:
> On Fri, Jul 27, 2018 at 1:55 AM, Derek Basehore <dbasehore@xxxxxxxxxxxx> wrote:
>> This enables the async suspend property for i2c devices. This reduces
>> the suspend/resume time considerably on platforms with multiple i2c
>> devices (such as a trackpad or touchscreen).
>
> How did you test this?

It was tested on Apollolake Chromebook devices.
Â
>
> Especially on Chromebooks based on Intel Cherrytrail / Braswell
> platforms, they have a painful PMIC vs. OS design solution.
>
> +Cc: Hans, who did a lot in this area.

We disable suspend of the i2c controller for the i2c-bus
to which the PMIc is connected on these platforms, so I do not
expect this to cause any new issues.

But this is something to keep an eye on,

Regards,

Hans