drivers/usb/storage/option_ms.c

   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