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 #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         /*
  69          * Some of the devices need to be asked for a response, but we don't
  70          * care what that response is.
  71          */
  72         usb_stor_bulk_transfer_buf(us,
  73                         us->recv_bulk_pipe,
  74                         buffer, RESPONSE_LEN, NULL);
  75
  76         /* Read the CSW */
  77         usb_stor_bulk_transfer_buf(us,
  78                         us->recv_bulk_pipe,
  79                         buffer, 13, NULL);
  80
  81         result = USB_STOR_XFER_GOOD;
  82
  83 out:
  84         kfree(buffer);
  85         return result;
  86 }
  87
  88 static int option_inquiry(struct us_data *us)
  89 {
  90         const unsigned char inquiry_msg[] = {
  91           0x55, 0x53, 0x42, 0x43, 0x12, 0x34, 0x56, 0x78,
  92           0x24, 0x00, 0x00, 0x00, 0x80, 0x00, 0x06, 0x12,
  93           0x00, 0x00, 0x00, 0x24, 0x00, 0x00, 0x00, 0x00,
  94           0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00
  95         };
  96         char *buffer;
  97         int result;
  98
  99         usb_stor_dbg(us, "Option MS: %s\n", "device inquiry for vendor name");
 100
 101         buffer = kzalloc(0x24, GFP_KERNEL);
 102         if (buffer == NULL)
 103                 return USB_STOR_TRANSPORT_ERROR;
 104
 105         memcpy(buffer, inquiry_msg, sizeof(inquiry_msg));
 106         result = usb_stor_bulk_transfer_buf(us,
 107                         us->send_bulk_pipe,
 108                         buffer, sizeof(inquiry_msg), NULL);
 109         if (result != USB_STOR_XFER_GOOD) {
 110                 result = USB_STOR_XFER_ERROR;
 111                 goto out;
 112         }
 113
 114         result = usb_stor_bulk_transfer_buf(us,
 115                         us->recv_bulk_pipe,
 116                         buffer, 0x24, NULL);
 117         if (result != USB_STOR_XFER_GOOD) {
 118                 result = USB_STOR_XFER_ERROR;
 119                 goto out;
 120         }
 121
 122         result = memcmp(buffer+8, "Option", 6);
 123
 124         if (result != 0)
 125                 result = memcmp(buffer+8, "ZCOPTION", 8);
 126
 127         /* Read the CSW */
 128         usb_stor_bulk_transfer_buf(us,
 129                         us->recv_bulk_pipe,
 130                         buffer, 13, NULL);
 131
 132 out:
 133         kfree(buffer);
 134         return result;
 135 }
 136
 137
 138 int option_ms_init(struct us_data *us)
 139 {
 140         int result;
 141
 142         usb_stor_dbg(us, "Option MS: %s\n", "option_ms_init called");
 143
 144         /*
 145          * Additional test for vendor information via INQUIRY,
 146          * because some vendor/product IDs are ambiguous
 147          */
 148         result = option_inquiry(us);
 149         if (result != 0) {
 150                 usb_stor_dbg(us, "Option MS: %s\n",
 151                              "vendor is not Option or not determinable, no action taken");
 152                 return 0;
 153         } else
 154                 usb_stor_dbg(us, "Option MS: %s\n",
 155                              "this is a genuine Option device, proceeding");
 156
 157         /* Force Modem mode */
 158         if (option_zero_cd == ZCD_FORCE_MODEM) {
 159                 usb_stor_dbg(us, "Option MS: %s\n", "Forcing Modem Mode");
 160                 result = option_rezero(us);
 161                 if (result != USB_STOR_XFER_GOOD)
 162                         usb_stor_dbg(us, "Option MS: %s\n",
 163                                      "Failed to switch to modem mode");
 164                 return -EIO;
 165         } else if (option_zero_cd == ZCD_ALLOW_MS) {
 166                 /* Allow Mass Storage mode (keep CD-Rom) */
 167                 usb_stor_dbg(us, "Option MS: %s\n",
 168                              "Allowing Mass Storage Mode if device requests it");
 169         }
 170
 171         return 0;
 172 }
 173