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".) Best regards, Yoshihiro Shimoda > Thanks, > > / magnus > -- 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
