xref: /openbmc/linux/drivers/usb/storage/option_ms.c (revision e8e0929d)
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 
25 #include "usb.h"
26 #include "transport.h"
27 #include "option_ms.h"
28 #include "debug.h"
29 
30 #define ZCD_FORCE_MODEM			0x01
31 #define ZCD_ALLOW_MS 			0x02
32 
33 static unsigned int option_zero_cd = ZCD_FORCE_MODEM;
34 module_param(option_zero_cd, uint, S_IRUGO | S_IWUSR);
35 MODULE_PARM_DESC(option_zero_cd, "ZeroCD mode (1=Force Modem (default),"
36 		 " 2=Allow CD-Rom");
37 
38 #define RESPONSE_LEN 1024
39 
40 static int option_rezero(struct us_data *us)
41 {
42 	const unsigned char rezero_msg[] = {
43 	  0x55, 0x53, 0x42, 0x43, 0x78, 0x56, 0x34, 0x12,
44 	  0x01, 0x00, 0x00, 0x00, 0x80, 0x00, 0x06, 0x01,
45 	  0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
46 	  0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00
47 	};
48 	char *buffer;
49 	int result;
50 
51 	US_DEBUGP("Option MS: %s", "DEVICE MODE SWITCH\n");
52 
53 	buffer = kzalloc(RESPONSE_LEN, GFP_KERNEL);
54 	if (buffer == NULL)
55 		return USB_STOR_TRANSPORT_ERROR;
56 
57 	memcpy(buffer, rezero_msg, sizeof(rezero_msg));
58 	result = usb_stor_bulk_transfer_buf(us,
59 			us->send_bulk_pipe,
60 			buffer, sizeof(rezero_msg), NULL);
61 	if (result != USB_STOR_XFER_GOOD) {
62 		result = USB_STOR_XFER_ERROR;
63 		goto out;
64 	}
65 
66 	/* Some of the devices need to be asked for a response, but we don't
67 	 * care what that response is.
68 	 */
69 	usb_stor_bulk_transfer_buf(us,
70 			us->recv_bulk_pipe,
71 			buffer, RESPONSE_LEN, NULL);
72 
73 	/* Read the CSW */
74 	usb_stor_bulk_transfer_buf(us,
75 			us->recv_bulk_pipe,
76 			buffer, 13, NULL);
77 
78 	result = USB_STOR_XFER_GOOD;
79 
80 out:
81 	kfree(buffer);
82 	return result;
83 }
84 
85 static int option_inquiry(struct us_data *us)
86 {
87 	const unsigned char inquiry_msg[] = {
88 	  0x55, 0x53, 0x42, 0x43, 0x12, 0x34, 0x56, 0x78,
89 	  0x24, 0x00, 0x00, 0x00, 0x80, 0x00, 0x06, 0x12,
90 	  0x00, 0x00, 0x00, 0x24, 0x00, 0x00, 0x00, 0x00,
91 	  0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00
92 	};
93 	char *buffer;
94 	int result;
95 
96 	US_DEBUGP("Option MS: %s", "device inquiry for vendor name\n");
97 
98 	buffer = kzalloc(0x24, GFP_KERNEL);
99 	if (buffer == NULL)
100 		return USB_STOR_TRANSPORT_ERROR;
101 
102 	memcpy(buffer, inquiry_msg, sizeof(inquiry_msg));
103 	result = usb_stor_bulk_transfer_buf(us,
104 			us->send_bulk_pipe,
105 			buffer, sizeof(inquiry_msg), NULL);
106 	if (result != USB_STOR_XFER_GOOD) {
107 		result = USB_STOR_XFER_ERROR;
108 		goto out;
109 	}
110 
111 	result = usb_stor_bulk_transfer_buf(us,
112 			us->recv_bulk_pipe,
113 			buffer, 0x24, NULL);
114 	if (result != USB_STOR_XFER_GOOD) {
115 		result = USB_STOR_XFER_ERROR;
116 		goto out;
117 	}
118 
119 	result = memcmp(buffer+8, "Option", 6);
120 
121 	if (result != 0)
122 		result = memcmp(buffer+8, "ZCOPTION", 8);
123 
124 	/* Read the CSW */
125 	usb_stor_bulk_transfer_buf(us,
126 			us->recv_bulk_pipe,
127 			buffer, 13, NULL);
128 
129 out:
130 	kfree(buffer);
131 	return result;
132 }
133 
134 
135 int option_ms_init(struct us_data *us)
136 {
137 	int result;
138 
139 	US_DEBUGP("Option MS: option_ms_init called\n");
140 
141 	/* Additional test for vendor information via INQUIRY,
142 	 * because some vendor/product IDs are ambiguous
143 	 */
144 	result = option_inquiry(us);
145 	if (result != 0) {
146 		US_DEBUGP("Option MS: vendor is not Option or not determinable,"
147 			  " no action taken\n");
148 		return 0;
149 	} else
150 		US_DEBUGP("Option MS: this is a genuine Option device,"
151 			  " proceeding\n");
152 
153 	/* Force Modem mode */
154 	if (option_zero_cd == ZCD_FORCE_MODEM) {
155 		US_DEBUGP("Option MS: %s", "Forcing Modem Mode\n");
156 		result = option_rezero(us);
157 		if (result != USB_STOR_XFER_GOOD)
158 			US_DEBUGP("Option MS: Failed to switch to modem mode.\n");
159 		return -EIO;
160 	} else if (option_zero_cd == ZCD_ALLOW_MS) {
161 		/* Allow Mass Storage mode (keep CD-Rom) */
162 		US_DEBUGP("Option MS: %s", "Allowing Mass Storage Mode if device"
163 		          " requests it\n");
164 	}
165 
166 	return 0;
167 }
168 
169