Re: [PATCH v4 2/2] i2c: add ACPI support for I2C mux ports

From: Mika Westerberg
Date: Fri Oct 23 2015 - 09:13:24 EST


On Fri, Oct 23, 2015 at 12:16:11PM +0200, Wolfram Sang wrote:
> On Fri, Oct 23, 2015 at 11:40:13AM +0300, Mika Westerberg wrote:
> > On Thu, Oct 22, 2015 at 02:17:42AM -0700, Dustin Byford wrote:
> > > Although I2C mux devices are easily enumerated using ACPI (_HID/_CID or
> > > device property compatible string match), enumerating I2C client devices
> > > connected through an I2C mux needs a little extra work.
> > >
> > > This change implements a method for describing an I2C device hierarchy that
> > > includes mux devices by using an ACPI Device() for each mux channel along
> > > with an _ADR to set the channel number for the device. See
> > > Documentation/acpi/i2c-muxes.txt for a simple example.
> > >
> > > To make this work the ismt, i801, and designware pci/platform devs now
> > > share an ACPI companion with their I2C adapter dev similar to how it's done
> > > in OF. This is done on the assumption that power management functions will
> > > not be called directly on the I2C dev that is sharing the ACPI node.
> > >
> > > Signed-off-by: Dustin Byford <dustin@xxxxxxxxxxxxxxxxxxx>
> >
> > This looks good to me.
> >
> > You did also some stylistic changes to the drivers in question which I
> > think should be placed to a separate patches.
>
> I am fine with those.
>
> > Regardless of that,
> >
> > Acked-by: Mika Westerberg <mika.westerberg@xxxxxxxxxxxxxxx>
>
> I would love to get a Tested-by for the designware part. Then, I could
> queue it for 4.4 already.

Tested on Intel Baytrail and Skylake and the existing I2C devices
(touchpad, touchscreen) still work so for the designware part you can
also add my,

Tested-by: Mika Westerberg <mika.westerberg@xxxxxxxxxxxxxxx>
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