Re: [PATCH v5 1/1] serial: core: Start managing serial controllers to enable runtime PM

From: Greg Kroah-Hartman
Date: Tue Jan 31 2023 - 05:10:41 EST


On Mon, Jan 16, 2023 at 09:59:58AM +0200, Tony Lindgren wrote:
> We want to enable runtime PM for serial port device drivers in a generic
> way. To do this, we want to have the serial core layer manage the
> registered physical serial controller devices.
>
> To do this, let's set up a struct device for the serial core controller
> as suggested by Greg and Jiri. The serial core controller devices are
> children of the physical serial port device. The serial core controller
> device is needed to support multiple different kind of ports connected
> to single physical serial port device.
>
> Let's also set up a struct device for the serial core port. The serial
> core port instances are children of the serial core controller device.

Looking better, but why is this new device a platform device? That
feels odd, you should never have a platform device hanging off of a
non-platform device, right?

What does the sysfs tree look like now with this patch applied?

thanks,

greg k-h