[PATCH] USB Storage: Revision of as202, Genesys quirk patch

In the slave_configure routine it's already too late for the host's
max_sector value to affect the scsi_device.  It's necessary to set the
queue value directly.  This revised patch takes care of that.

drivers/usb/storage/scsiglue.c

@@ -64,8 +64,10 @@ static const char* host_info(struct Scsi_Host *host)
 	return "SCSI emulation for USB Mass Storage devices";
 }
 
-static int slave_configure (struct scsi_device *sdev)
+static int slave_configure(struct scsi_device *sdev)
 {
+	struct us_data *us = (struct us_data *) sdev->host->hostdata[0];
+
 	/* Scatter-gather buffers (all but the last) must have a length
 	 * divisible by the bulk maxpacket size.  Otherwise a data packet
 	 * would end up being short, causing a premature end to the data
@@ -76,6 +78,16 @@ static int slave_configure (struct scsi_device *sdev)
 	 * the end, scatter-gather buffers follow page boundaries. */
 	blk_queue_dma_alignment(sdev->request_queue, (512 - 1));
 
+	/* Devices using Genesys Logic chips cause a lot of trouble for
+	 * high-speed transfers; they die unpredictably when given more
+	 * than 64 KB of data at a time.  If we detect such a device,
+	 * reduce the maximum transfer size to 64 KB = 128 sectors. */
+
+#define USB_VENDOR_ID_GENESYS	0x05e3		// Needs a standard location
+	if (us->pusb_dev->descriptor.idVendor == USB_VENDOR_ID_GENESYS &&
+			us->pusb_dev->speed == USB_SPEED_HIGH)
+		blk_queue_max_sectors(sdev->request_queue, 128);
+
 	/* this is to satisify the compiler, tho I don't think the 
 	 * return code is ever checked anywhere. */
 	return 0;