Re: [PATCH 2/6] phy: improved lookup method

Kishon Vijay Abraham I
2014-09-22T11:38:07Z

Hi,

On Thursday 18 September 2014 03:55 PM, Heikki Krogerus wrote:
> On Mon, Sep 15, 2014 at 03:35:08PM +0300, Heikki Krogerus wrote:
>> On Fri, Sep 12, 2014 at 08:16:01PM +0530, Kishon Vijay Abraham I wrote:
>>> Assume you have 2 phys in your system..
>>> static struct phy_lookup usb_lookup = {
>>> .phy_name = "phy-usb.0",
>>> .dev_id = "usb.0",
>>> .con_id = "usb",
>>> };
>>>
>>> static struct phy_lookup sata_lookup = {
>>> .phy_name = "sata-usb.1",
>>> .dev_id = "sata.0",
>>> .con_id = "sata",
>>> };
>>>
>>> First you do modprobe phy-usb, the probe of USB PHY driver gets invoked and it
>>> creates the PHY. The phy-core will find a free id (now it will be 0) and then
>>> name the phy as phy-usb.0.
>>> Then with modprobe phy-sata, the phy-core will create phy-sata.1.
>>>
>>> This is an ideal case where the .phy_name in phy_lookup matches.
>>>
>>> Consider if the order is flipped and the user does modprobe phy-sata first. The
>>> phy_names won't match anymore (the sata phy device name would be "sata-usb.0").
>
> Actually, I don't think there would be this problem if we used the
> name of the actual device which is the parent of phy devices, right?

hmm.. but if the parent is a multi-phy phy provider (like pipe3 PHY driver), we
might end up with the same problem.

Thanks
Kishon