xref: /openbmc/linux/drivers/usb/storage/option_ms.c (revision 12eb4683)
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 
35 static unsigned int option_zero_cd = ZCD_FORCE_MODEM;
36 module_param(option_zero_cd, uint, S_IRUGO | S_IWUSR);
37 MODULE_PARM_DESC(option_zero_cd, "ZeroCD mode (1=Force Modem (default),"
38 		 " 2=Allow CD-Rom");
39 
40 #define RESPONSE_LEN 1024
41 
42 static 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 
82 out:
83 	kfree(buffer);
84 	return result;
85 }
86 
87 static 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 
131 out:
132 	kfree(buffer);
133 	return result;
134 }
135 
136 
137 int 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