xref: /openbmc/linux/drivers/usb/storage/option_ms.c (revision 7fe2f639)
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 
26 #include "usb.h"
27 #include "transport.h"
28 #include "option_ms.h"
29 #include "debug.h"
30 
31 #define ZCD_FORCE_MODEM			0x01
32 #define ZCD_ALLOW_MS 			0x02
33 
34 static unsigned int option_zero_cd = ZCD_FORCE_MODEM;
35 module_param(option_zero_cd, uint, S_IRUGO | S_IWUSR);
36 MODULE_PARM_DESC(option_zero_cd, "ZeroCD mode (1=Force Modem (default),"
37 		 " 2=Allow CD-Rom");
38 
39 #define RESPONSE_LEN 1024
40 
41 static int option_rezero(struct us_data *us)
42 {
43 	const unsigned char rezero_msg[] = {
44 	  0x55, 0x53, 0x42, 0x43, 0x78, 0x56, 0x34, 0x12,
45 	  0x01, 0x00, 0x00, 0x00, 0x80, 0x00, 0x06, 0x01,
46 	  0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
47 	  0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00
48 	};
49 	char *buffer;
50 	int result;
51 
52 	US_DEBUGP("Option MS: %s", "DEVICE MODE SWITCH\n");
53 
54 	buffer = kzalloc(RESPONSE_LEN, GFP_KERNEL);
55 	if (buffer == NULL)
56 		return USB_STOR_TRANSPORT_ERROR;
57 
58 	memcpy(buffer, rezero_msg, sizeof(rezero_msg));
59 	result = usb_stor_bulk_transfer_buf(us,
60 			us->send_bulk_pipe,
61 			buffer, sizeof(rezero_msg), NULL);
62 	if (result != USB_STOR_XFER_GOOD) {
63 		result = USB_STOR_XFER_ERROR;
64 		goto out;
65 	}
66 
67 	/* Some of the devices need to be asked for a response, but we don't
68 	 * care what that response is.
69 	 */
70 	usb_stor_bulk_transfer_buf(us,
71 			us->recv_bulk_pipe,
72 			buffer, RESPONSE_LEN, NULL);
73 
74 	/* Read the CSW */
75 	usb_stor_bulk_transfer_buf(us,
76 			us->recv_bulk_pipe,
77 			buffer, 13, NULL);
78 
79 	result = USB_STOR_XFER_GOOD;
80 
81 out:
82 	kfree(buffer);
83 	return result;
84 }
85 
86 static int option_inquiry(struct us_data *us)
87 {
88 	const unsigned char inquiry_msg[] = {
89 	  0x55, 0x53, 0x42, 0x43, 0x12, 0x34, 0x56, 0x78,
90 	  0x24, 0x00, 0x00, 0x00, 0x80, 0x00, 0x06, 0x12,
91 	  0x00, 0x00, 0x00, 0x24, 0x00, 0x00, 0x00, 0x00,
92 	  0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00
93 	};
94 	char *buffer;
95 	int result;
96 
97 	US_DEBUGP("Option MS: %s", "device inquiry for vendor name\n");
98 
99 	buffer = kzalloc(0x24, GFP_KERNEL);
100 	if (buffer == NULL)
101 		return USB_STOR_TRANSPORT_ERROR;
102 
103 	memcpy(buffer, inquiry_msg, sizeof(inquiry_msg));
104 	result = usb_stor_bulk_transfer_buf(us,
105 			us->send_bulk_pipe,
106 			buffer, sizeof(inquiry_msg), NULL);
107 	if (result != USB_STOR_XFER_GOOD) {
108 		result = USB_STOR_XFER_ERROR;
109 		goto out;
110 	}
111 
112 	result = usb_stor_bulk_transfer_buf(us,
113 			us->recv_bulk_pipe,
114 			buffer, 0x24, NULL);
115 	if (result != USB_STOR_XFER_GOOD) {
116 		result = USB_STOR_XFER_ERROR;
117 		goto out;
118 	}
119 
120 	result = memcmp(buffer+8, "Option", 6);
121 
122 	if (result != 0)
123 		result = memcmp(buffer+8, "ZCOPTION", 8);
124 
125 	/* Read the CSW */
126 	usb_stor_bulk_transfer_buf(us,
127 			us->recv_bulk_pipe,
128 			buffer, 13, NULL);
129 
130 out:
131 	kfree(buffer);
132 	return result;
133 }
134 
135 
136 int option_ms_init(struct us_data *us)
137 {
138 	int result;
139 
140 	US_DEBUGP("Option MS: option_ms_init called\n");
141 
142 	/* Additional test for vendor information via INQUIRY,
143 	 * because some vendor/product IDs are ambiguous
144 	 */
145 	result = option_inquiry(us);
146 	if (result != 0) {
147 		US_DEBUGP("Option MS: vendor is not Option or not determinable,"
148 			  " no action taken\n");
149 		return 0;
150 	} else
151 		US_DEBUGP("Option MS: this is a genuine Option device,"
152 			  " proceeding\n");
153 
154 	/* Force Modem mode */
155 	if (option_zero_cd == ZCD_FORCE_MODEM) {
156 		US_DEBUGP("Option MS: %s", "Forcing Modem Mode\n");
157 		result = option_rezero(us);
158 		if (result != USB_STOR_XFER_GOOD)
159 			US_DEBUGP("Option MS: Failed to switch to modem mode.\n");
160 		return -EIO;
161 	} else if (option_zero_cd == ZCD_ALLOW_MS) {
162 		/* Allow Mass Storage mode (keep CD-Rom) */
163 		US_DEBUGP("Option MS: %s", "Allowing Mass Storage Mode if device"
164 		          " requests it\n");
165 	}
166 
167 	return 0;
168 }
169 
170