Re: [PATCH v6 1/1] usb: host: xhci-plat: add support for the R-Car H2 and M2 xHCI controllers

Hi Felipe,

(2014/06/18 14:15), Magnus Damm wrote:

Hi Felipe,

On Fri, Jun 13, 2014 at 11:25 PM, Felipe Balbi [off-list ref] wrote:

quoted

Hi,

On Fri, Jun 13, 2014 at 09:20:31PM +0900, Yoshihiro Shimoda wrote:

< snip >

quoted

quoted

+/* This function needs to initialize a "phy" of usb before */

initializing a PHY looks like something that the PHY layer should do.
Why don't you write a PHY driver and teach xhci-core about PHYs ? Then,
more people would benefit.

Could you please clarify what you would like Shimoda-san to do?

Like Ben and Shimoda-san mentioned, there is already a PHY driver
developed for this SoC. The PHY driver is however shared in various
ways. For example, on one particular SoC the same PHY driver is
interfacing to a total of 3 different variants of USB controllers
where XHCI is one of them. And to make things even more complicated,
depending on SoC variant the XHCI hardware may or may not be available
- but the PHY portion is more or less the same.

Putting the firmware loader in the XHCI driver like this at least
keeps it together with the rest of the XHCI stuff and also makes it
possible to easily access the XHCI I/O register window for firmware
loading. Moving the firmware loading to the PHY driver however
complicates the situation when it comes to Kconfig handling of XHCI
and PHY driver and also forces the PHY driver to access the XHCI
hardware I/O registers for firmware loading...

Do you have any comment about Magnus's comment?

Best regards,
Yoshihiro Shimoda

Cheers,

/ magnus