On Sat, May 10, 2014 at 09:18:36PM +0800, Shawn Guo wrote: > + Robin and David, > > On Sat, May 10, 2014 at 07:10:05PM +0800, Peter Chen wrote: > > On Fri, May 09, 2014 at 09:00:47PM +0800, Shawn Guo wrote: > > > I'm running next-20140508 kernel on imx6q-sabresd board with USB > > > mouse/keyboard connected to OTG port. It works well on 3.15-rc but > > > is broken on recent linux-next kernel with the message like below. > > > > > > ... > > > usb 1-1: device v413c p2107 is not supported > > > hub 1-0:1.0: unable to enumerate USB device on port 1 > > > > > > With the help from Peter, I found that the issue shows up only when > > > CONFIG_USB_OTG_FSM is enabled. The option is enabled by commit 8fd2f1f > > > (ARM: imx_v6_v7_defconfig: Enable drivers for i.MX51 USB Host support.) > > > from IMX tree. > > > > > > I guess this is a sign that chipidea otg_fsm driver is buggy? I do not > > > think dropping CONFIG_USB_OTG_FSM selection from imx_v6_v7_defconfig is > > > a solution, and we need to fix the issue in usb driver, right? > > > > > > > No, Shawn. The solution of this problem is drop CONFIG_USB_OTG_FSM, I > > guess Denis added it wrongly. > > > > According to Embedded Hosts & OTG spec, OTG devices and Embedded Hosts > > both have Targeted Host functionality, and each Targeted Host has > > its TPL (Targeted Peripheral List), only the devices are at TPL > > are supported by Targeted Host. > > > > Current Linux TPL only contains limited devices, each Targeted Host > > needs to update its TPL when it makes product, (The comments at > > otg_whitelist.h also mention it), and the devices are not at TPL > > will not be supported, and will report to user as "an unsupported > > device" error, at current Linux configuration, once the CONFIG_USB_OTG_FSM > > and CONFIG_USB_OTG are chosen, the host will be Targeted Host. > > > > The reason why Shawn met this problem is: the imx_v6_v7_defconfig set > > CONFIG_USB_OTG_FSM, so the CONFIG_USB_OTG and CONFIG_USB_OTG_WHITELIST > > are set according to dependency, it makes imx6 device as Targeted Host, > > but the devices connected at Shawn's board are not at TPL, so they are > > not be supported. > > > > In a word the CONFIG_USB_OTG_FSM should not be chosen for > > defauly kernel configuration. The CONFIG_USB_OTG_FSM should only be chosen > > by default when this device goes to make product and the TPL is updated > > accordingly. > > Thanks for the explanation, Peter. > > So this is what I see from USB Kconfig. > > config USB_OTG_FSM > tristate "USB 2.0 OTG FSM implementation" > depends on USB > select USB_OTG > select USB_PHY > > config USB_OTG_WHITELIST > bool "Rely on OTG Targeted Peripherals List" > depends on USB_OTG || EXPERT > default y if USB_OTG > > I see that USB_OTG_FSM has a dependency on USB_OTG, and > USB_OTG_WHITELIST depends on USB_OTG, but USB_OTG does *not* depends > on USB_OTG_WHITELIST. > > I'm not sure why we have 'default y if USB_OTG' for USB_OTG_WHITELIST, > when this option only makes sense for product producers per your > explanation. So maybe dropping the 'default y' is the right fix? > > diff --git a/drivers/usb/core/Kconfig b/drivers/usb/core/Kconfig > index cb8e991..9081757 100644 > --- a/drivers/usb/core/Kconfig > +++ b/drivers/usb/core/Kconfig > @@ -65,7 +65,6 @@ config USB_OTG > config USB_OTG_WHITELIST > bool "Rely on OTG Targeted Peripherals List" > depends on USB_OTG || EXPERT > - default y if USB_OTG > help > If you say Y here, the "otg_whitelist.h" file will be used as a > product whitelist, so USB peripherals not listed there will be > > Shawn As Peter suggested, do not enable OTG_FSM in defconfig since there are very few HNP&SRP capable device in market. With OTG_FSM enabled, even USB_OTG_WHITELIST is not selected, the OTG port still can't work the same as before if you connect a normal usb device to it. Li Jun -- 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
