From mboxrd@z Thu Jan 1 00:00:00 1970 From: Sergei Shtylyov Date: Wed, 09 Apr 2014 18:16:53 +0000 Subject: Re: [PATCH 1/2] usb: rename 'phy' field of 'struct usb_hcd' to 'transceiver' Message-Id: <53458E95.4080505@cogentembedded.com> List-Id: References: In-Reply-To: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: Alan Stern Cc: Stephen Warren , gregkh@linuxfoundation.org, linux-usb@vger.kernel.org, Peter.Chen@freescale.com, thierry.reding@gmail.com, balbi@ti.com, linux-tegra@vger.kernel.org, linux-omap@vger.kernel.org, linux-sh@vger.kernel.org, magnus.damm@gmail.com Hello. On 04/09/2014 09:56 PM, Alan Stern wrote: >>> Ok, the existing field is being replaced by something? I didn't get that >> No, not replaced. I'm adding the support for generic PHY to the existing >> USB PHY support. I thought that was clear from the changelog. >>> from the patch description; I thought the new name in this patch was >>> going to be it. In that case, a temporary name of usb_phy for the >>> existing field, or adding the new field as gen_phy sound reasonable. >> OK, I'll respin the patch #2 with 'gen_phy' and remove the patch #1. > What is the reason for all of this? That is, can you explain the > difference between USB PHY support and general PHY support, and why we > need both? The generic PHY framework (drivers/phy/phy-core.c) supports multifunction "complex" PHYs (some functions of which may be related to USB). My case is a Renesas R-Car generation 2 PHY that can switch two USB ports between different USB controllers (one PCI and one non-PCI on each port); I just haven't CCed linux-usb on my driver submission. Though there's already drivers/phy/usb/ driver for that hardware, it failed to meet the expectations (dynamic setting of the port multiplexing depending on what USB host/gadget drivers are loaded), so I had to write a new driver. I guess I don't need to describe drivers/phy/usb/ framework in detail, do I? It only provides for single-function "simple" USB PHYs... > Alan Stern WBR, Sergei