Avoid I/O errors when issuing SCSI ioctls to JMicron USB/ATA bridge

[Alexandre Oliva <oliva@lsd.ic.unicamp.br>]

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Hi, Alan,

Here's the patch that implements the fix you suggested to avoid the
I/O errors that I was running into with my new USB enclosure with a
JMicron USB/ATA bridge, while issuing scsi-io USN or other such
queries used by Fedora's mkinitrd.
http://bugzilla.kernel.org/show_bug.cgi?id=9638#c85

/proc/bus/usb/devices:
T:  Bus=01 Lev=01 Prnt=01 Port=01 Cnt=01 Dev#=  2 Spd=480 MxCh= 0
D:  Ver= 2.00 Cls=00(>ifc ) Sub=00 Prot=00 MxPS=64 #Cfgs=  1
P:  Vendor=152d ProdID=2329 Rev= 1.00
S:  Manufacturer=JMicron
S:  Product=USB to ATA/ATAPI Bridge
S:  SerialNumber=152D20329000
C:* #Ifs= 1 Cfg#= 1 Atr=c0 MxPwr=  2mA
I:* If#= 0 Alt= 0 #EPs= 2 Cls=08(stor.) Sub=06 Prot=50 Driver=usb-storage
E:  Ad=81(I) Atr=02(Bulk) MxPS= 512 Ivl=0ms
E:  Ad=02(O) Atr=02(Bulk) MxPS= 512 Ivl=0ms



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--- linux-2.6/drivers/usb/storage/unusual_devs.h~	2008-07-13 18:51:29.000000000 -0300
+++ linux-2.6/drivers/usb/storage/unusual_devs.h	2008-10-07 23:38:38.000000000 -0300
@@ -1694,6 +1694,15 @@
 		US_SC_DEVICE, US_PR_DEVICE, NULL,
 		US_FL_IGNORE_RESIDUE ),
 
+/* Reported by Alexandre Oliva <oliva@lsd.ic.unicamp.br>
+ * JMicron responds to USN and several other SCSI ioctls with a
+ * residue that causes subsequent I/O requests to fail.  */
+UNUSUAL_DEV(  0x152d, 0x2329, 0x0000, 0x9999,
+	        "JMicron",
+	        "USB to ATA/ATAPI Bridge",
+	        US_SC_DEVICE, US_PR_DEVICE, NULL,
+	        US_FL_IGNORE_RESIDUE ),
+
 /* Reported by Robert Schedel <r.schedel@yahoo.de>
  * Note: this is a 'super top' device like the above 14cd/6600 device */
 UNUSUAL_DEV(  0x1652, 0x6600, 0x0201, 0x0201,

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-- 
Alexandre Oliva         http://www.lsd.ic.unicamp.br/~oliva/
Free Software Evangelist  oliva@{lsd.ic.unicamp.br, gnu.org}
FSFLA Board Member       ¡Sé Libre! => http://www.fsfla.org/
Red Hat Compiler Engineer   aoliva@{redhat.com, gcc.gnu.org}