On Mon, 7 Apr 2008 03:35:38 -0700, "Bryan Wu" <cooloney@xxxxxxxxxx> wrote: > On Mon, Apr 7, 2008 at 3:19 AM, Felipe Balbi <me@xxxxxxxxxxxxxxx> wrote: >> >> >> >> On Mon, 7 Apr 2008 03:15:38 -0700, "Bryan Wu" <cooloney@xxxxxxxxxx> > wrote: >> > Hi folks, >> > >> > Here is our bug tracker, >> > >> > https://blackfin.uclinux.org/gf/project/uclinux-dist/tracker/?action=TrackerItemEdit&tracker_id=141&tracker_item_id=3788 >> > >> > ZiO! CF card reader is here: >> > http://www.psism.com/zio.htm >> > >> > - Firstly, MUSB is working as in host mode which can be figured out > by >> > the debug message. >> > - Enumeration of the ZiO! CF card reader is OK. >> > - When the upper drivers/usb/storage/shuttle_usbat.c try to send out >> > the first packet: >> > -- >> > /* Enable peripheral control signals */ >> > rc = usbat_write_user_io(us, >> > USBAT_UIO_OE1 | USBAT_UIO_OE0, >> > USBAT_UIO_EPAD | USBAT_UIO_1); >> > if (rc != USB_STOR_XFER_GOOD) >> > return USB_STOR_TRANSPORT_ERROR; >> > -- >> > >> > - Finally, we got VBUS_ERROR interrupt in peripheral mode. I don't >> > know how to recover it. >> > If I am not wrong, the ZiO! CF card reader must have dropped the VBUS >> > and this triggered the mode change of MUSB. >> > >> > Are you guys have any idea about this? >> > >> > B.T.W, I found the packet sequence of >> > drivers/usb/storage/shuttle_usbat.c is not the same as Windows Host >> > does. >> > So I modified the code to send out the same packet as Windows Host. >> > The result is the same. >> >> It's probably drawing more the 100mA, try using a self-powered usb hub >> attached >> to musb and zio to hub. >> > > So that means it's possible related with the hardware design? > Unfortunately, there is no self-powered usb hub on my side. > Only have normal full-speed usb hub which is powered by usb host. So > maybe we should add this kind of usb devices to the black list of MUSB > driver. MUSB can only source up to 100mA on the bus, which is perfectly ok on the otg point of view. If you attach a device that needs more than 100mA you'll get a vbus error. To have a clue about how much your reader does attach it to you host pc and issue lsusb -v -d <vendorid>:<productid> and check the MaxPower field. Of course this is just a string and if the manufacturer decided to mess it up it's not our fault :-p The correct way to measure the current consumption would be with a multimeter, but the string usually give you a clue :-) -- Best Regards, Felipe Balbi http://felipebalbi.com me@xxxxxxxxxxxxxxx -- To unsubscribe from this list: send the line "unsubscribe linux-omap" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
