On Fri, 27 Jun 2014, Michael Büsch wrote: > On Fri, 27 Jun 2014 14:42:01 -0400 (EDT) > Alan Stern <stern@xxxxxxxxxxxxxxxxxxx> wrote: > > > Michael, can you post the "lsusb -v" output for this device? I see it > > is made by JMicron; they are notorious for buggy USB-ATA bridges. > > Of course. Here you go: > > Bus 004 Device 009: ID 152d:0567 JMicron Technology Corp. / JMicron USA Technology Corp. > Device Descriptor: > bLength 18 > bDescriptorType 1 > bcdUSB 3.00 > bDeviceClass 0 (Defined at Interface level) > bDeviceSubClass 0 > bDeviceProtocol 0 > bMaxPacketSize0 9 > idVendor 0x152d JMicron Technology Corp. / JMicron USA Technology Corp. > idProduct 0x0567 > bcdDevice 1.14 > iManufacturer 1 JMicron > iProduct 2 USB to ATA/ATAPI Bridge > iSerial 3 xxx > bNumConfigurations 1 > Configuration Descriptor: > bLength 9 > bDescriptorType 2 > wTotalLength 121 > bNumInterfaces 1 > bConfigurationValue 1 > iConfiguration 4 USB Mass Storage > bmAttributes 0xc0 > Self Powered > MaxPower 2mA ... > MaxPower=2mA is a nice guess for a hard disk. ;) That refers to the amount of power the device draws from the USB bus. Since the disk drive is self-powered, it doesn't use much bus power. Does the patch below do what you and James want? Alan Stern Index: usb-3.16/include/linux/usb_usual.h =================================================================== --- usb-3.16.orig/include/linux/usb_usual.h +++ usb-3.16/include/linux/usb_usual.h @@ -70,7 +70,9 @@ US_FLAG(NEEDS_CAP16, 0x00400000) \ /* cannot handle READ_CAPACITY_10 */ \ US_FLAG(IGNORE_UAS, 0x00800000) \ - /* Device advertises UAS but it is broken */ + /* Device advertises UAS but it is broken */ \ + US_FLAG(BROKEN_FUA, 0x01000000) \ + /* Cannot handle FUA in WRITE CDBs */ \ #define US_FLAG(name, value) US_FL_##name = value , enum { US_DO_ALL_FLAGS }; Index: usb-3.16/include/scsi/scsi_device.h =================================================================== --- usb-3.16.orig/include/scsi/scsi_device.h +++ usb-3.16/include/scsi/scsi_device.h @@ -173,6 +173,7 @@ struct scsi_device { unsigned is_visible:1; /* is the device visible in sysfs */ unsigned wce_default_on:1; /* Cache is ON by default */ unsigned no_dif:1; /* T10 PI (DIF) should be disabled */ + unsigned broken_fua:1; /* Don't set FUA bit */ atomic_t disk_events_disable_depth; /* disable depth for disk events */ Index: usb-3.16/drivers/usb/storage/unusual_devs.h =================================================================== --- usb-3.16.orig/drivers/usb/storage/unusual_devs.h +++ usb-3.16/drivers/usb/storage/unusual_devs.h @@ -1936,6 +1936,13 @@ UNUSUAL_DEV( 0x14cd, 0x6600, 0x0201, 0x USB_SC_DEVICE, USB_PR_DEVICE, NULL, US_FL_IGNORE_RESIDUE ), +/* Reported by Michael Büsch <m@xxxxxxx> */ +UNUSUAL_DEV( 0x152d, 0x0567, 0x0114, 0x0114, + "JMicron", + "USB to ATA/ATAPI Bridge", + USB_SC_DEVICE, USB_PR_DEVICE, NULL, + US_FL_BROKEN_FUA ), + /* Reported by Alexandre Oliva <oliva@xxxxxxxxxxxxxxxxx> * JMicron responds to USN and several other SCSI ioctls with a * residue that causes subsequent I/O requests to fail. */ Index: usb-3.16/drivers/usb/storage/scsiglue.c =================================================================== --- usb-3.16.orig/drivers/usb/storage/scsiglue.c +++ usb-3.16/drivers/usb/storage/scsiglue.c @@ -256,6 +256,10 @@ static int slave_configure(struct scsi_d if (us->fflags & US_FL_WRITE_CACHE) sdev->wce_default_on = 1; + /* A few buggy USB-ATA bridges don't understand FUA */ + if (us->fflags & US_FL_BROKEN_FUA) + sdev->broken_fua = 1; + } else { /* Non-disk-type devices don't need to blacklist any pages Index: usb-3.16/drivers/scsi/sd.c =================================================================== --- usb-3.16.orig/drivers/scsi/sd.c +++ usb-3.16/drivers/scsi/sd.c @@ -2441,7 +2441,10 @@ sd_read_cache_type(struct scsi_disk *sdk } sdkp->DPOFUA = (data.device_specific & 0x10) != 0; - if (sdkp->DPOFUA && !sdkp->device->use_10_for_rw) { + if (sdp->broken_fua) { + sd_first_printk(KERN_NOTICE, sdkp, "Disabling FUA\n"); + sdkp->DPOFUA = 0; + } else if (sdkp->DPOFUA && !sdkp->device->use_10_for_rw) { sd_first_printk(KERN_NOTICE, sdkp, "Uses READ/WRITE(6), disabling FUA\n"); sdkp->DPOFUA = 0; -- 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