1// SPDX-License-Identifier: GPL-2.0+
2/*
3 * Driver for Option High Speed Mobile Devices.
4 *
5 * (c) 2008 Dan Williams <dcbw@redhat.com>
6 *
7 * Inspiration taken from sierra_ms.c by Kevin Lloyd <klloyd@sierrawireless.com>
8 */
9
10#include <linux/usb.h>
11#include <linux/slab.h>
12#include <linux/module.h>
13
14#include "usb.h"
15#include "transport.h"
16#include "option_ms.h"
17#include "debug.h"
18
19#define ZCD_FORCE_MODEM 0x01
20#define ZCD_ALLOW_MS 0x02
21
22static unsigned int option_zero_cd = ZCD_FORCE_MODEM;
23module_param(option_zero_cd, uint, S_IRUGO | S_IWUSR);
24MODULE_PARM_DESC(option_zero_cd, "ZeroCD mode (1=Force Modem (default),"
25 " 2=Allow CD-Rom");
26
27#define RESPONSE_LEN 1024
28
29static int option_rezero(struct us_data *us)
30{
31 static const unsigned char rezero_msg[] = {
32 0x55, 0x53, 0x42, 0x43, 0x78, 0x56, 0x34, 0x12,
33 0x01, 0x00, 0x00, 0x00, 0x80, 0x00, 0x06, 0x01,
34 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
35 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00
36 };
37 char *buffer;
38 int result;
39
40 usb_stor_dbg(us, "Option MS: %s\n", "DEVICE MODE SWITCH");
41
42 buffer = kzalloc(RESPONSE_LEN, GFP_KERNEL);
43 if (buffer == NULL)
44 return USB_STOR_TRANSPORT_ERROR;
45
46 memcpy(to: buffer, from: rezero_msg, len: sizeof(rezero_msg));
47 result = usb_stor_bulk_transfer_buf(us,
48 pipe: us->send_bulk_pipe,
49 buf: buffer, length: sizeof(rezero_msg), NULL);
50 if (result != USB_STOR_XFER_GOOD) {
51 result = USB_STOR_XFER_ERROR;
52 goto out;
53 }
54
55 /*
56 * Some of the devices need to be asked for a response, but we don't
57 * care what that response is.
58 */
59 usb_stor_bulk_transfer_buf(us,
60 pipe: us->recv_bulk_pipe,
61 buf: buffer, RESPONSE_LEN, NULL);
62
63 /* Read the CSW */
64 usb_stor_bulk_transfer_buf(us,
65 pipe: us->recv_bulk_pipe,
66 buf: buffer, length: 13, NULL);
67
68 result = USB_STOR_XFER_GOOD;
69
70out:
71 kfree(objp: buffer);
72 return result;
73}
74
75static int option_inquiry(struct us_data *us)
76{
77 static const unsigned char inquiry_msg[] = {
78 0x55, 0x53, 0x42, 0x43, 0x12, 0x34, 0x56, 0x78,
79 0x24, 0x00, 0x00, 0x00, 0x80, 0x00, 0x06, 0x12,
80 0x00, 0x00, 0x00, 0x24, 0x00, 0x00, 0x00, 0x00,
81 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00
82 };
83 char *buffer;
84 int result;
85
86 usb_stor_dbg(us, "Option MS: %s\n", "device inquiry for vendor name");
87
88 buffer = kzalloc(0x24, GFP_KERNEL);
89 if (buffer == NULL)
90 return USB_STOR_TRANSPORT_ERROR;
91
92 memcpy(to: buffer, from: inquiry_msg, len: sizeof(inquiry_msg));
93 result = usb_stor_bulk_transfer_buf(us,
94 pipe: us->send_bulk_pipe,
95 buf: buffer, length: sizeof(inquiry_msg), NULL);
96 if (result != USB_STOR_XFER_GOOD) {
97 result = USB_STOR_XFER_ERROR;
98 goto out;
99 }
100
101 result = usb_stor_bulk_transfer_buf(us,
102 pipe: us->recv_bulk_pipe,
103 buf: buffer, length: 0x24, NULL);
104 if (result != USB_STOR_XFER_GOOD) {
105 result = USB_STOR_XFER_ERROR;
106 goto out;
107 }
108
109 result = memcmp(buffer+8, "Option", 6);
110
111 if (result != 0)
112 result = memcmp(buffer+8, "ZCOPTION", 8);
113
114 /* Read the CSW */
115 usb_stor_bulk_transfer_buf(us,
116 pipe: us->recv_bulk_pipe,
117 buf: buffer, length: 13, NULL);
118
119out:
120 kfree(objp: buffer);
121 return result;
122}
123
124
125int option_ms_init(struct us_data *us)
126{
127 int result;
128
129 usb_stor_dbg(us, "Option MS: %s\n", "option_ms_init called");
130
131 /*
132 * Additional test for vendor information via INQUIRY,
133 * because some vendor/product IDs are ambiguous
134 */
135 result = option_inquiry(us);
136 if (result != 0) {
137 usb_stor_dbg(us, "Option MS: %s\n",
138 "vendor is not Option or not determinable, no action taken");
139 return 0;
140 } else
141 usb_stor_dbg(us, "Option MS: %s\n",
142 "this is a genuine Option device, proceeding");
143
144 /* Force Modem mode */
145 if (option_zero_cd == ZCD_FORCE_MODEM) {
146 usb_stor_dbg(us, "Option MS: %s\n", "Forcing Modem Mode");
147 result = option_rezero(us);
148 if (result != USB_STOR_XFER_GOOD)
149 usb_stor_dbg(us, "Option MS: %s\n",
150 "Failed to switch to modem mode");
151 return -EIO;
152 } else if (option_zero_cd == ZCD_ALLOW_MS) {
153 /* Allow Mass Storage mode (keep CD-Rom) */
154 usb_stor_dbg(us, "Option MS: %s\n",
155 "Allowing Mass Storage Mode if device requests it");
156 }
157
158 return 0;
159}
160
161