Re: [PATCH 08/12] doc: binding: pwrseq-usb-generic: add binding doc for generic usb power sequence driver

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 



On Mon, Jun 20, 2016 at 11:16:07AM -0500, Rob Herring wrote:
> On Mon, Jun 20, 2016 at 07:26:51PM +0800, Peter Chen wrote:

> > If the node has property "power-sequence", the pwrseq core will create
> > related platform device, and the driver under pwrseq driver will handle
> > power sequence stuffs. 

> This I have issue with. If you are creating a platform device here, you 
> are trying to work-around limitations in the linux driver model. Either 
> we need some sort of pre-probe hook to the drivers to call or each 
> parent node driver is responsible for checking and calling pwr-seq 
> functions for child nodes. e.g. The host controller calls pwr-seq for 
> the hub, the hub driver calls the power seq for the asix chip. Soon as 
> we have a case too complex for the generic pwr-seq, we're going to need 
> the pre-probe hook as I don't want to see a continual expansion of 
> generic pwr-seq binding for ever more complex cases.

I think it's fairly clear that we need one or both of these mechanisms
for enumerable buses in embedded contexts - it's something that keeps
croping up.

Attachment: signature.asc
Description: PGP signature


[Index of Archives]     [Linux Media]     [Linux Input]     [Linux Audio Users]     [Yosemite News]     [Linux Kernel]     [Linux SCSI]     [Old Linux USB Devel Archive]

  Powered by Linux