On Tue, 9 Sep 2014, Hans de Goede wrote: > Even with REPORT SUPPORTED OPERATION CODES blacklisted the ASM1051 chipset > still does not work when combined with some disks, e.g. a Crucial M500 ssd. > > When used with a troublesome disk, the chipset throws all kinds of USB errors, > and eventually hangs, where as in BOT mode it works fine. > > To make matters worse the ASM1051 chipset and older versions of the ASM1053 > chipset use the same usb-id. > > When connected over USB-3 the 2 can be told apart by the number of streams > they support. So this patch adds some less then pretty code to disable uas for > the ASM1051. When connected over USB-2, simply disable uas alltogether for > devices with the shared usb-id. > > This ends up disabling uas in many cases where it actually works fine, which > is unfortunate, but better then leaving some users with completely non working > external disks. This patch adds a log level explaining how perfomance conscious > users can re-enable uas. > > Cc: stable@xxxxxxxxxxxxxxx # 3.16 > Signed-off-by: Hans de Goede <hdegoede@xxxxxxxxxx> > --- > drivers/usb/storage/uas-detect.h | 34 ++++++++++++++++++++++++++++++---- > 1 file changed, 30 insertions(+), 4 deletions(-) > > diff --git a/drivers/usb/storage/uas-detect.h b/drivers/usb/storage/uas-detect.h > index 503ac5c..3119f3f 100644 > --- a/drivers/usb/storage/uas-detect.h > +++ b/drivers/usb/storage/uas-detect.h > @@ -59,10 +59,6 @@ static int uas_use_uas_driver(struct usb_interface *intf, > unsigned long flags = id->driver_info; > int r, alt; > > - usb_stor_adjust_quirks(udev, &flags); > - > - if (flags & US_FL_IGNORE_UAS) > - return 0; > > alt = uas_find_uas_alt_setting(intf); > if (alt < 0) > @@ -72,6 +68,36 @@ static int uas_use_uas_driver(struct usb_interface *intf, > if (r < 0) > return 0; > > + /* > + * ASM1051 and older ASM1053 devices have the same usb-id, and UAS is > + * broken with some disks on the ASM1051, use the number of streams to > + * differentiate between the 2. Newer ASM1053 devices also support 32 > + * streams, but have a different product-id. > + */ > + if (udev->descriptor.idVendor == 0x174c && > + udev->descriptor.idProduct == 0x55aa) { > + if (udev->speed < USB_SPEED_SUPER) { > + /* No streams info, assume ASM1051E */ > + dev_warn(&udev->dev, "Assuming ASM1051E chipset\n"); > + flags |= US_FL_IGNORE_UAS; > + } else if (usb_ss_max_streams(&eps[1]->ss_ep_comp) == 32) { > + dev_warn(&udev->dev, "Detected ASM1051E chipset\n"); > + flags |= US_FL_IGNORE_UAS; > + } > + } > + > + usb_stor_adjust_quirks(udev, &flags); This won't work. usb_stor_adjust_quirks masks out all the quirks that it handles before applying the user-specified quirks. Therefore it will erase your US_FL_IGNORE_UAS flag. You might as well remove this call and leave the earlier call to usb_stor_adjust_quirks (in the first hunk of the patch) as is. Alan Stern -- To unsubscribe from this list: send the line "unsubscribe linux-scsi" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html