File-copy from v4.4.100

This is the result of 'cp' from a linux-stable tree with the 'v4.4.100'
tag checked out (commit 26d6298789e695c9f627ce49a7bbd2286405798a) on
git://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git

Please refer to that tree for all history prior to this point.

Change-Id: I8a9ee2aea93cd29c52c847d0ce33091a73ae6afe
diff --git a/drivers/usb/storage/option_ms.c b/drivers/usb/storage/option_ms.c
new file mode 100644
index 0000000..b2b35b1
--- /dev/null
+++ b/drivers/usb/storage/option_ms.c
@@ -0,0 +1,171 @@
+/*
+ * Driver for Option High Speed Mobile Devices.
+ *
+ *   (c) 2008 Dan Williams <dcbw@redhat.com>
+ *
+ * Inspiration taken from sierra_ms.c by Kevin Lloyd <klloyd@sierrawireless.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License along
+ * with this program; if not, write to the Free Software Foundation, Inc.,
+ * 675 Mass Ave, Cambridge, MA 02139, USA.
+ */
+
+#include <linux/usb.h>
+#include <linux/slab.h>
+#include <linux/module.h>
+
+#include "usb.h"
+#include "transport.h"
+#include "option_ms.h"
+#include "debug.h"
+
+#define ZCD_FORCE_MODEM			0x01
+#define ZCD_ALLOW_MS 			0x02
+
+static unsigned int option_zero_cd = ZCD_FORCE_MODEM;
+module_param(option_zero_cd, uint, S_IRUGO | S_IWUSR);
+MODULE_PARM_DESC(option_zero_cd, "ZeroCD mode (1=Force Modem (default),"
+		 " 2=Allow CD-Rom");
+
+#define RESPONSE_LEN 1024
+
+static int option_rezero(struct us_data *us)
+{
+	const unsigned char rezero_msg[] = {
+	  0x55, 0x53, 0x42, 0x43, 0x78, 0x56, 0x34, 0x12,
+	  0x01, 0x00, 0x00, 0x00, 0x80, 0x00, 0x06, 0x01,
+	  0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+	  0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00
+	};
+	char *buffer;
+	int result;
+
+	usb_stor_dbg(us, "Option MS: %s\n", "DEVICE MODE SWITCH");
+
+	buffer = kzalloc(RESPONSE_LEN, GFP_KERNEL);
+	if (buffer == NULL)
+		return USB_STOR_TRANSPORT_ERROR;
+
+	memcpy(buffer, rezero_msg, sizeof(rezero_msg));
+	result = usb_stor_bulk_transfer_buf(us,
+			us->send_bulk_pipe,
+			buffer, sizeof(rezero_msg), NULL);
+	if (result != USB_STOR_XFER_GOOD) {
+		result = USB_STOR_XFER_ERROR;
+		goto out;
+	}
+
+	/* Some of the devices need to be asked for a response, but we don't
+	 * care what that response is.
+	 */
+	usb_stor_bulk_transfer_buf(us,
+			us->recv_bulk_pipe,
+			buffer, RESPONSE_LEN, NULL);
+
+	/* Read the CSW */
+	usb_stor_bulk_transfer_buf(us,
+			us->recv_bulk_pipe,
+			buffer, 13, NULL);
+
+	result = USB_STOR_XFER_GOOD;
+
+out:
+	kfree(buffer);
+	return result;
+}
+
+static int option_inquiry(struct us_data *us)
+{
+	const unsigned char inquiry_msg[] = {
+	  0x55, 0x53, 0x42, 0x43, 0x12, 0x34, 0x56, 0x78,
+	  0x24, 0x00, 0x00, 0x00, 0x80, 0x00, 0x06, 0x12,
+	  0x00, 0x00, 0x00, 0x24, 0x00, 0x00, 0x00, 0x00,
+	  0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00
+	};
+	char *buffer;
+	int result;
+
+	usb_stor_dbg(us, "Option MS: %s\n", "device inquiry for vendor name");
+
+	buffer = kzalloc(0x24, GFP_KERNEL);
+	if (buffer == NULL)
+		return USB_STOR_TRANSPORT_ERROR;
+
+	memcpy(buffer, inquiry_msg, sizeof(inquiry_msg));
+	result = usb_stor_bulk_transfer_buf(us,
+			us->send_bulk_pipe,
+			buffer, sizeof(inquiry_msg), NULL);
+	if (result != USB_STOR_XFER_GOOD) {
+		result = USB_STOR_XFER_ERROR;
+		goto out;
+	}
+
+	result = usb_stor_bulk_transfer_buf(us,
+			us->recv_bulk_pipe,
+			buffer, 0x24, NULL);
+	if (result != USB_STOR_XFER_GOOD) {
+		result = USB_STOR_XFER_ERROR;
+		goto out;
+	}
+
+	result = memcmp(buffer+8, "Option", 6);
+
+	if (result != 0)
+		result = memcmp(buffer+8, "ZCOPTION", 8);
+
+	/* Read the CSW */
+	usb_stor_bulk_transfer_buf(us,
+			us->recv_bulk_pipe,
+			buffer, 13, NULL);
+
+out:
+	kfree(buffer);
+	return result;
+}
+
+
+int option_ms_init(struct us_data *us)
+{
+	int result;
+
+	usb_stor_dbg(us, "Option MS: %s\n", "option_ms_init called");
+
+	/* Additional test for vendor information via INQUIRY,
+	 * because some vendor/product IDs are ambiguous
+	 */
+	result = option_inquiry(us);
+	if (result != 0) {
+		usb_stor_dbg(us, "Option MS: %s\n",
+			     "vendor is not Option or not determinable, no action taken");
+		return 0;
+	} else
+		usb_stor_dbg(us, "Option MS: %s\n",
+			     "this is a genuine Option device, proceeding");
+
+	/* Force Modem mode */
+	if (option_zero_cd == ZCD_FORCE_MODEM) {
+		usb_stor_dbg(us, "Option MS: %s\n", "Forcing Modem Mode");
+		result = option_rezero(us);
+		if (result != USB_STOR_XFER_GOOD)
+			usb_stor_dbg(us, "Option MS: %s\n",
+				     "Failed to switch to modem mode");
+		return -EIO;
+	} else if (option_zero_cd == ZCD_ALLOW_MS) {
+		/* Allow Mass Storage mode (keep CD-Rom) */
+		usb_stor_dbg(us, "Option MS: %s\n",
+			     "Allowing Mass Storage Mode if device requests it");
+	}
+
+	return 0;
+}
+