1/*
2 * Driver for Option High Speed Mobile Devices.
3 *
4 *   (c) 2008 Dan Williams <dcbw@redhat.com>
5 *
6 * Inspiration taken from sierra_ms.c by Kevin Lloyd <klloyd@sierrawireless.com>
7 *
8 * This program is free software; you can redistribute it and/or modify
9 * it under the terms of the GNU General Public License as published by
10 * the Free Software Foundation; either version 2 of the License, or
11 * (at your option) any later version.
12 *
13 * This program is distributed in the hope that it will be useful, but
14 * WITHOUT ANY WARRANTY; without even the implied warranty of
15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
16 * General Public License for more details.
17 *
18 * You should have received a copy of the GNU General Public License along
19 * with this program; if not, write to the Free Software Foundation, Inc.,
20 * 675 Mass Ave, Cambridge, MA 02139, USA.
21 */
22
23#include <linux/usb.h>
24#include <linux/slab.h>
25#include <linux/module.h>
26
27#include "usb.h"
28#include "transport.h"
29#include "option_ms.h"
30#include "debug.h"
31
32#define ZCD_FORCE_MODEM			0x01
33#define ZCD_ALLOW_MS 			0x02
34
35static unsigned int option_zero_cd = ZCD_FORCE_MODEM;
36module_param(option_zero_cd, uint, S_IRUGO | S_IWUSR);
37MODULE_PARM_DESC(option_zero_cd, "ZeroCD mode (1=Force Modem (default),"
38		 " 2=Allow CD-Rom");
39
40#define RESPONSE_LEN 1024
41
42static int option_rezero(struct us_data *us)
43{
44	const unsigned char rezero_msg[] = {
45	  0x55, 0x53, 0x42, 0x43, 0x78, 0x56, 0x34, 0x12,
46	  0x01, 0x00, 0x00, 0x00, 0x80, 0x00, 0x06, 0x01,
47	  0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
48	  0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00
49	};
50	char *buffer;
51	int result;
52
53	usb_stor_dbg(us, "Option MS: %s\n", "DEVICE MODE SWITCH");
54
55	buffer = kzalloc(RESPONSE_LEN, GFP_KERNEL);
56	if (buffer == NULL)
57		return USB_STOR_TRANSPORT_ERROR;
58
59	memcpy(buffer, rezero_msg, sizeof(rezero_msg));
60	result = usb_stor_bulk_transfer_buf(us,
61			us->send_bulk_pipe,
62			buffer, sizeof(rezero_msg), NULL);
63	if (result != USB_STOR_XFER_GOOD) {
64		result = USB_STOR_XFER_ERROR;
65		goto out;
66	}
67
68	/* Some of the devices need to be asked for a response, but we don't
69	 * care what that response is.
70	 */
71	usb_stor_bulk_transfer_buf(us,
72			us->recv_bulk_pipe,
73			buffer, RESPONSE_LEN, NULL);
74
75	/* Read the CSW */
76	usb_stor_bulk_transfer_buf(us,
77			us->recv_bulk_pipe,
78			buffer, 13, NULL);
79
80	result = USB_STOR_XFER_GOOD;
81
82out:
83	kfree(buffer);
84	return result;
85}
86
87static int option_inquiry(struct us_data *us)
88{
89	const unsigned char inquiry_msg[] = {
90	  0x55, 0x53, 0x42, 0x43, 0x12, 0x34, 0x56, 0x78,
91	  0x24, 0x00, 0x00, 0x00, 0x80, 0x00, 0x06, 0x12,
92	  0x00, 0x00, 0x00, 0x24, 0x00, 0x00, 0x00, 0x00,
93	  0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00
94	};
95	char *buffer;
96	int result;
97
98	usb_stor_dbg(us, "Option MS: %s\n", "device inquiry for vendor name");
99
100	buffer = kzalloc(0x24, GFP_KERNEL);
101	if (buffer == NULL)
102		return USB_STOR_TRANSPORT_ERROR;
103
104	memcpy(buffer, inquiry_msg, sizeof(inquiry_msg));
105	result = usb_stor_bulk_transfer_buf(us,
106			us->send_bulk_pipe,
107			buffer, sizeof(inquiry_msg), NULL);
108	if (result != USB_STOR_XFER_GOOD) {
109		result = USB_STOR_XFER_ERROR;
110		goto out;
111	}
112
113	result = usb_stor_bulk_transfer_buf(us,
114			us->recv_bulk_pipe,
115			buffer, 0x24, NULL);
116	if (result != USB_STOR_XFER_GOOD) {
117		result = USB_STOR_XFER_ERROR;
118		goto out;
119	}
120
121	result = memcmp(buffer+8, "Option", 6);
122
123	if (result != 0)
124		result = memcmp(buffer+8, "ZCOPTION", 8);
125
126	/* Read the CSW */
127	usb_stor_bulk_transfer_buf(us,
128			us->recv_bulk_pipe,
129			buffer, 13, NULL);
130
131out:
132	kfree(buffer);
133	return result;
134}
135
136
137int option_ms_init(struct us_data *us)
138{
139	int result;
140
141	usb_stor_dbg(us, "Option MS: %s\n", "option_ms_init called");
142
143	/* Additional test for vendor information via INQUIRY,
144	 * because some vendor/product IDs are ambiguous
145	 */
146	result = option_inquiry(us);
147	if (result != 0) {
148		usb_stor_dbg(us, "Option MS: %s\n",
149			     "vendor is not Option or not determinable, no action taken");
150		return 0;
151	} else
152		usb_stor_dbg(us, "Option MS: %s\n",
153			     "this is a genuine Option device, proceeding");
154
155	/* Force Modem mode */
156	if (option_zero_cd == ZCD_FORCE_MODEM) {
157		usb_stor_dbg(us, "Option MS: %s\n", "Forcing Modem Mode");
158		result = option_rezero(us);
159		if (result != USB_STOR_XFER_GOOD)
160			usb_stor_dbg(us, "Option MS: %s\n",
161				     "Failed to switch to modem mode");
162		return -EIO;
163	} else if (option_zero_cd == ZCD_ALLOW_MS) {
164		/* Allow Mass Storage mode (keep CD-Rom) */
165		usb_stor_dbg(us, "Option MS: %s\n",
166			     "Allowing Mass Storage Mode if device requests it");
167	}
168
169	return 0;
170}
171
172