aboutsummaryrefslogtreecommitdiffstats
path: root/drivers/usb/storage/option_ms.c
blob: d41cc0a970f79a147660da239bdc014612396354 (plain) (blame)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
/*
 * 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 "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;

	US_DEBUGP("Option MS: %s", "DEVICE MODE SWITCH\n");

	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;

	US_DEBUGP("Option MS: %s", "device inquiry for vendor name\n");

	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);

	/* 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;

	US_DEBUGP("Option MS: option_ms_init called\n");

	/* Additional test for vendor information via INQUIRY,
	 * because some vendor/product IDs are ambiguous
	 */
	result = option_inquiry(us);
	if (result != 0) {
		US_DEBUGP("Option MS: vendor is not Option or not determinable,"
			  " no action taken\n");
		return 0;
	} else
		US_DEBUGP("Option MS: this is a genuine Option device,"
			  " proceeding\n");

	/* Force Modem mode */
	if (option_zero_cd == ZCD_FORCE_MODEM) {
		US_DEBUGP("Option MS: %s", "Forcing Modem Mode\n");
		result = option_rezero(us);
		if (result != USB_STOR_XFER_GOOD)
			US_DEBUGP("Option MS: Failed to switch to modem mode.\n");
		return -EIO;
	} else if (option_zero_cd == ZCD_ALLOW_MS) {
		/* Allow Mass Storage mode (keep CD-Rom) */
		US_DEBUGP("Option MS: %s", "Allowing Mass Storage Mode if device"
		          " requests it\n");
	}

	return 0;
}