On Mon, 1 Apr 2019, Biju Das wrote: > Hi Alan, > > Thanks for the feedback. > > > Subject: Re: [PATCH 04/12] usb: host: ehci-r8a77470: Add EHCI support for > > Renesas RZ/G1C devices > > > > On Mon, 1 Apr 2019, Biju Das wrote: > > > > > This patch adds the glue code required to ensure the on-chip EHCI > > > controller works on RZ/G1C(a.k.a R8A77470) SoC's from Renesas. > > > > You should explain what this new glue code does. And why is it needed? > > Glue code initializes following registers on the host > > 1) initializing interrupt enable > 2) OVC detection timer > 3) suspend/ resume timer register > > Without glue code, interrupt generation is disabled. Good. This information should be added to the patch description. > > Can't you use the existing ehci-platform driver instead? > > > This driver is almost similar to generic ehci-platform except that it needs to do > some platform initialization as mentioned above. If I am correct, we cannot do > any platform initialization in generic code. Are you sure you can't? Also, have you considered modifying ehci-platform.c, in a general-purpose way, such that you could use it and still get this platform-specific work done? For example, you could add some callbacks to the usb_ehci_pdata structure. Or maybe you can use the callbacks that are already present, with no modifications needed. > The reason for the new driver is because of the below discussion > https://patchwork.kernel.org/patch/10655853/ I didn't notice anything in that discussion which would prevent you from using ehci-platform.c (possibly with a few modifications). Alan Stern
