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
  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