On Wed, Oct 29, 2014 at 08:19:30PM +0900, Yoshihiro Shimoda wrote: > Hi Magnus-san, > > (2014/10/29 15:53), Magnus Damm wrote: > > On Fri, Oct 24, 2014 at 7:41 PM, Yoshihiro Shimoda > > <yoshihiro.shimoda.uh@xxxxxxxxxxx> wrote: > >> Since the PHY of USB3.0 and EHCI/OHCI ch2 are the same, the USB3.0 > >> driver cannot use the phy driver when the EHCI/OHCI ch2 already used it: > >> > >> phy phy-e6590100.usb-phy.3: phy init failed --> -16 > >> xhci-hcd: probe of ee000000.usb failed with error -16 > >> > >> If so, we have to unbind the EHCI/OHCI ch2, and then we have to bind > >> the USB3.0 driver as the following: > >> > >> echo 0000:02:02.0 > /sys/bus/pci/drivers/ehci-pci/unbind > >> echo 0000:02:01.0 > /sys/bus/pci/drivers/ohci-pci/unbind > >> echo ee000000.usb > /sys/bus/platform/drivers/xhci-hcd/bind > >> > >> Note that there will be pinctrl-related error messages if both > >> internal PCI and USB3.0 are enabled but they should be just ignored: > >> > >> sh-pfc e6060000.pfc: pin GP_5_22 already requested by ee0d0000.pci; cannot claim for ee000000.usb > >> sh-pfc e6060000.pfc: pin-182 (ee000000.usb) status -22 > >> ata1: SATA link down (SStatus 0 SControl 300) > >> sh-pfc e6060000.pfc: could not request pin 182 (GP_5_22) from group usb2 on device sh-pfc > >> > >> Signed-off-by: Yoshihiro Shimoda <yoshihiro.shimoda.uh@xxxxxxxxxxx> > >> --- > >> arch/arm/boot/dts/r8a7790-lager.dts | 6 ++++++ > >> 1 file changed, 6 insertions(+) > > > > Hi Shimoda-san, > > > > Thanks for your patch. I'm fine with this patch as a first step, but > > I'm wondering what the reason is to prioritize USB 2.0 over USB 3.0? > > I investigated this reason today, and I found the reason is > request_firmware(). I checked the following environments: > > Case 1: xHCI and EHCI and OHCI are enabled "=y" Case 2: xHCI and EHCI > and OHCI are loadable modules "=m" Case 3: xHCI and EHCI and OHCI are > enabled "=y", and CONFIG_EXTRA_FIRMWARE is enabled > > The results are: - In "Case 1", EHCI and OHCI are probed first because > xHCI didn't find the firmware. - In "Case 2" and "Case 3", xHCI is > probed first. > > > Is the current order just based on device init order? In my mind the > > expected behavior would be to always use USB 3.0 if it happens to be > > available in the hardware, specified in the DTS, enabled by the kernel > > configuration and firmware is loadable. Or does some case exist where > > it is better to use USB 2.0? I suspect no. > > I agree with you. > > > So I wonder if you have any plans how to make USB 3.0 enabled by > > default on Lager? > > It depends on a kernel config. I'm not sure of the shmobile_defconfig > strategy. But, in my opinion, one of a solution is kernel modules (this > means the "Case 2".) It sounds like we should enable CONFIG_EXTRA_FIRMWARE in shmobile_defconfig. I wonder what if any fallout we can foresee occurring if we do that. -- To unsubscribe from this list: send the line "unsubscribe linux-usb" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
