Merge tag 'for-6.2-rc4-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave...
[platform/kernel/linux-rpi.git] / drivers / usb / storage / option_ms.c
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
22 static unsigned int option_zero_cd = ZCD_FORCE_MODEM;
23 module_param(option_zero_cd, uint, S_IRUGO | S_IWUSR);
24 MODULE_PARM_DESC(option_zero_cd, "ZeroCD mode (1=Force Modem (default),"
25                  " 2=Allow CD-Rom");
26
27 #define RESPONSE_LEN 1024
28
29 static 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(buffer, rezero_msg, sizeof(rezero_msg));
47         result = usb_stor_bulk_transfer_buf(us,
48                         us->send_bulk_pipe,
49                         buffer, 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                         us->recv_bulk_pipe,
61                         buffer, RESPONSE_LEN, NULL);
62
63         /* Read the CSW */
64         usb_stor_bulk_transfer_buf(us,
65                         us->recv_bulk_pipe,
66                         buffer, 13, NULL);
67
68         result = USB_STOR_XFER_GOOD;
69
70 out:
71         kfree(buffer);
72         return result;
73 }
74
75 static 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(buffer, inquiry_msg, sizeof(inquiry_msg));
93         result = usb_stor_bulk_transfer_buf(us,
94                         us->send_bulk_pipe,
95                         buffer, 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                         us->recv_bulk_pipe,
103                         buffer, 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                         us->recv_bulk_pipe,
117                         buffer, 13, NULL);
118
119 out:
120         kfree(buffer);
121         return result;
122 }
123
124
125 int 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