[PATCH 3.16 199/328] usb: uas: add support for more quirk flags

[Ben Hutchings]

3.16.62-rc1 review patch.  If anyone has any objections, please let me know.

------------------

From: Oliver Neukum <oneukum@xxxxxxxx>

commit 42d1c6d4a06a77b3ab206a919b9050c3080f3a71 upstream.

The hope that UAS devices would be less broken than old style storage
devices has turned out to be unfounded. Make UAS support more of the
quirk flags of the old driver.

Signed-off-by: Oliver Neukum <oneukum@xxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
[bwh: Backported to 3.16: adjust context]
Signed-off-by: Ben Hutchings <ben@xxxxxxxxxxxxxxx>
---
 drivers/usb/storage/uas.c | 21 +++++++++++++++++++++
 1 file changed, 21 insertions(+)

--- a/drivers/usb/storage/uas.c
+++ b/drivers/usb/storage/uas.c
@@ -991,6 +991,26 @@ static int uas_slave_configure(struct sc
 	if (devinfo->flags & US_FL_BROKEN_FUA)
 		sdev->broken_fua = 1;
 
+	/*
+	 * Some disks return the total number of blocks in response
+	 * to READ CAPACITY rather than the highest block number.
+	 * If this device makes that mistake, tell the sd driver.
+	 */
+	if (devinfo->flags & US_FL_FIX_CAPACITY)
+		sdev->fix_capacity = 1;
+
+	/*
+	 * Some devices don't like MODE SENSE with page=0x3f,
+	 * which is the command used for checking if a device
+	 * is write-protected.  Now that we tell the sd driver
+	 * to do a 192-byte transfer with this command the
+	 * majority of devices work fine, but a few still can't
+	 * handle it.  The sd driver will simply assume those
+	 * devices are write-enabled.
+	 */
+	if (devinfo->flags & US_FL_NO_WP_DETECT)
+		sdev->skip_ms_page_3f = 1;
+
 	scsi_set_tag_type(sdev, MSG_ORDERED_TAG);
 	scsi_activate_tcq(sdev, devinfo->qdepth - 2);
 	return 0;