Hi, > From: Rob Herring > Sent: Friday, April 22, 2016 10:29 PM > > On Fri, Apr 22, 2016 at 4:36 AM, Felipe Balbi > <felipe.balbi@xxxxxxxxxxxxxxx> wrote: > > > > Hi, > > > > Yoshihiro Shimoda <yoshihiro.shimoda.uh@xxxxxxxxxxx> writes: > >> The firmware of R-Car USB 3.0 host controller will control the reset. > >> So, if the xhci driver doesn't do firmware downloading (e.g. kernel > >> configuration is CONFIG_USB_XHCI_PLATFORM=y and CONFIG_USB_XHCI_RCAR > >> is not set), the reset of USB 3.0 host controller doesn't work > >> correctly. Then, the host controller will cause long wait in > >> xhci_reset() because the CMD_RESET bit of op_regs->command is not > >> cleared for 10 seconds. > >> > >> So, this patch modifies the xhci_rcar_init_quirk() in xhci-rcar.h > >> to exit the probe function immediately. > >> > >> Fixes: 4ac8918f3a7 (usb: host: xhci-plat: add support for the R-Car H2 and M2 xHCI controllers) > >> Cc: <stable@xxxxxxxxxxxxxxx> # v3.17+ > >> Signed-off-by: Yoshihiro Shimoda <yoshihiro.shimoda.uh@xxxxxxxxxxx> > >> --- > >> Changes from v1: > >> - Revise the commit log. > >> (http://www.spinics.net/lists/stable/msg130007.html) > >> > >> drivers/usb/host/xhci-rcar.h | 6 +++++- > >> 1 file changed, 5 insertions(+), 1 deletion(-) > >> > >> diff --git a/drivers/usb/host/xhci-rcar.h b/drivers/usb/host/xhci-rcar.h > >> index 2941a25..2afed68 100644 > >> --- a/drivers/usb/host/xhci-rcar.h > >> +++ b/drivers/usb/host/xhci-rcar.h > >> @@ -24,7 +24,11 @@ static inline void xhci_rcar_start(struct usb_hcd *hcd) > >> > >> static inline int xhci_rcar_init_quirk(struct usb_hcd *hcd) > >> { > >> - return 0; > >> + /* > >> + * To avoid wait and timeout in xhci_reset() if CONFIG_XHCI_RCAR is > >> + * disabled, this function fails. > >> + */ > >> + return -ENODEV; > > > > okay, if I understood correctly the thing is that you have a kernel > > built with XHCI platform support but without XHCI RCAR support. Then, if > > you run this kernel on RCAR board, you see this CMD_RESET problem, > > right? > > > > Isn't this pointing to the fact that xhci-plat.ko built without RCAR > > isn't exactly compatible with RCAR ? > > > > IOW: > > > > diff --git a/drivers/usb/host/xhci-plat.c b/drivers/usb/host/xhci-plat.c > > index 676ea458148b..3e39320564ce 100644 > > --- a/drivers/usb/host/xhci-plat.c > > +++ b/drivers/usb/host/xhci-plat.c > > @@ -112,6 +112,7 @@ static const struct of_device_id usb_xhci_of_match[] = { > > }, { > > .compatible = "marvell,armada-380-xhci", > > .data = &xhci_plat_marvell_armada, > > +#if IS_ENABLED(CONFIG_USB_XHCI_RCAR) > > }, { > > .compatible = "renesas,xhci-r8a7790", > > .data = &xhci_plat_renesas_rcar_gen2, > > @@ -130,6 +131,7 @@ static const struct of_device_id usb_xhci_of_match[] = { > > }, { > > .compatible = "renesas,rcar-gen3-xhci", > > .data = &xhci_plat_renesas_rcar_gen3, > > +#endif > > }, > > {}, > > }; > > > > Rob, should we limit compatible flags like this ? Without > > CONFIG_USB_XHCI_RCAR, this driver won't work on RCAR but, as you can > > see, this driver might still work on other non-RCAR platforms. > > > > What's your take on this ? > > We should fix this in kconfig to always enable the option when RCAR is > enabled IMO. I could fix this in kconfig like the followings: diff --git a/arch/arm/mach-shmobile/Kconfig b/arch/arm/mach-shmobile/Kconfig index f2bc5c3..905d1d2 100644 --- a/arch/arm/mach-shmobile/Kconfig +++ b/arch/arm/mach-shmobile/Kconfig @@ -46,6 +46,7 @@ menuconfig ARCH_RENESAS select PINCTRL select ARCH_REQUIRE_GPIOLIB select ZONE_DMA if ARM_LPAE + select USB_XHCI_RCAR if USB_XHCI_HCD if ARCH_RENESAS diff --git a/arch/arm64/Kconfig.platforms b/arch/arm64/Kconfig.platforms index efa77c1..010d2b7 100644 --- a/arch/arm64/Kconfig.platforms +++ b/arch/arm64/Kconfig.platforms @@ -105,6 +105,7 @@ config ARCH_RENESAS select PM select PM_GENERIC_DOMAINS select RENESAS_IRQC + select USB_XHCI_RCAR if USB_XHCI_HCD help This enables support for the ARMv8 based Renesas SoCs. If this is acceptable, I will send each patch to arm / arm64. Best regards, Yoshihiro Shimoda > Rob
