ath9k_htc: Handle storage devices

Some AR7010 based devices are recognized as storage media.
Sending a CD-EJECT command to the device will 'convert' it into
a WLAN device. Do this within the driver itself, removing the
dependancy on an external program (usb_modeswitch).

Signed-off-by: Sujith Manoharan <Sujith.Manoharan@atheros.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

2 files changed, 69 insertions, 6 deletions

diff --git a/drivers/net/wireless/ath/ath9k/hif_usb.c b/drivers/net/wireless/ath/ath9k/hif_usb.c
index 5ab3084eb9cb..fde54446973f 100644
--- a/drivers/net/wireless/ath/ath9k/hif_usb.c
+++ b/drivers/net/wireless/ath/ath9k/hif_usb.c
@@ -52,6 +52,9 @@ static struct usb_device_id ath9k_hif_usb_ids[] = {
         { USB_DEVICE(0x083A, 0xA704),
           .driver_info = AR9280_USB },  /* SMC Networks */
 
+        { USB_DEVICE(0x0cf3, 0x20ff),
+          .driver_info = STORAGE_DEVICE },
+
         { },
 };
 
@@ -934,6 +937,61 @@ static void ath9k_hif_usb_dev_deinit(struct hif_device_usb *hif_dev)
                 release_firmware(hif_dev->firmware);
 }
 
+/*
+ * An exact copy of the function from zd1211rw.
+ */
+static int send_eject_command(struct usb_interface *interface)
+{
+        struct usb_device *udev = interface_to_usbdev(interface);
+        struct usb_host_interface *iface_desc = &interface->altsetting[0];
+        struct usb_endpoint_descriptor *endpoint;
+        unsigned char *cmd;
+        u8 bulk_out_ep;
+        int r;
+
+        /* Find bulk out endpoint */
+        for (r = 1; r >= 0; r--) {
+                endpoint = &iface_desc->endpoint[r].desc;
+                if (usb_endpoint_dir_out(endpoint) &&
+                    usb_endpoint_xfer_bulk(endpoint)) {
+                        bulk_out_ep = endpoint->bEndpointAddress;
+                        break;
+                }
+        }
+        if (r == -1) {
+                dev_err(&udev->dev,
+                        "ath9k_htc: Could not find bulk out endpoint\n");
+                return -ENODEV;
+        }
+
+        cmd = kzalloc(31, GFP_KERNEL);
+        if (cmd == NULL)
+                return -ENODEV;
+
+        /* USB bulk command block */
+        cmd[0] = 0x55;  /* bulk command signature */
+        cmd[1] = 0x53;  /* bulk command signature */
+        cmd[2] = 0x42;  /* bulk command signature */
+        cmd[3] = 0x43;  /* bulk command signature */
+        cmd[14] = 6;    /* command length */
+
+        cmd[15] = 0x1b; /* SCSI command: START STOP UNIT */
+        cmd[19] = 0x2;  /* eject disc */
+
+        dev_info(&udev->dev, "Ejecting storage device...\n");
+        r = usb_bulk_msg(udev, usb_sndbulkpipe(udev, bulk_out_ep),
+                cmd, 31, NULL, 2000);
+        kfree(cmd);
+        if (r)
+                return r;
+
+        /* At this point, the device disconnects and reconnects with the real
+         * ID numbers. */
+
+        usb_set_intfdata(interface, NULL);
+        return 0;
+}
+
 static int ath9k_hif_usb_probe(struct usb_interface *interface,
                                const struct usb_device_id *id)
 {
@@ -941,6 +999,9 @@ static int ath9k_hif_usb_probe(struct usb_interface *interface,
         struct hif_device_usb *hif_dev;
         int ret = 0;
 
+        if (id->driver_info == STORAGE_DEVICE)
+                return send_eject_command(interface);
+
         hif_dev = kzalloc(sizeof(struct hif_device_usb), GFP_KERNEL);
         if (!hif_dev) {
                 ret = -ENOMEM;
@@ -1027,12 +1088,13 @@ static void ath9k_hif_usb_disconnect(struct usb_interface *interface)
         struct hif_device_usb *hif_dev = usb_get_intfdata(interface);
         bool unplugged = (udev->state == USB_STATE_NOTATTACHED) ? true : false;
 
-        if (hif_dev) {
-                ath9k_htc_hw_deinit(hif_dev->htc_handle, unplugged);
-                ath9k_htc_hw_free(hif_dev->htc_handle);
-                ath9k_hif_usb_dev_deinit(hif_dev);
-                usb_set_intfdata(interface, NULL);
-        }
+        if (!hif_dev)
+                return;
+
+        ath9k_htc_hw_deinit(hif_dev->htc_handle, unplugged);
+        ath9k_htc_hw_free(hif_dev->htc_handle);
+        ath9k_hif_usb_dev_deinit(hif_dev);
+        usb_set_intfdata(interface, NULL);
 
         if (!unplugged && (hif_dev->flags & HIF_USB_START))
                 ath9k_hif_usb_reboot(udev);
diff --git a/drivers/net/wireless/ath/ath9k/reg.h b/drivers/net/wireless/ath/ath9k/reg.h
index 64b226a78b2e..8fa8acfde62e 100644
--- a/drivers/net/wireless/ath/ath9k/reg.h
+++ b/drivers/net/wireless/ath/ath9k/reg.h
@@ -878,6 +878,7 @@
 enum ath_usb_dev {
         AR9280_USB = 1, /* AR7010 + AR9280, UB94 */
         AR9287_USB = 2, /* AR7010 + AR9287, UB95 */
+        STORAGE_DEVICE = 3,
 };
 
 #define AR_DEVID_7010(_ah) \