package/rt2x00/src/rt2x00firmware.c

   1 /*
   2         Copyright (C) 2004 - 2007 rt2x00 SourceForge Project
   3         <http://rt2x00.serialmonkey.com>
   4
   5         This program is free software; you can redistribute it and/or modify
   6         it under the terms of the GNU General Public License as published by
   7         the Free Software Foundation; either version 2 of the License, or
   8         (at your option) any later version.
   9
  10         This program is distributed in the hope that it will be useful,
  11         but WITHOUT ANY WARRANTY; without even the implied warranty of
  12         MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
  13         GNU General Public License for more details.
  14
  15         You should have received a copy of the GNU General Public License
  16         along with this program; if not, write to the
  17         Free Software Foundation, Inc.,
  18         59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
  19  */
  20
  21 /*
  22         Module: rt2x00lib
  23         Abstract: rt2x00 firmware loading routines.
  24  */
  25
  26 /*
  27  * Set enviroment defines for rt2x00.h
  28  */
  29 #define DRV_NAME "rt2x00lib"
  30
  31 #include <linux/crc-itu-t.h>
  32 #include <linux/kernel.h>
  33 #include <linux/module.h>
  34
  35 #include "rt2x00.h"
  36 #include "rt2x00lib.h"
  37
  38 static int rt2x00lib_request_firmware(struct rt2x00_dev *rt2x00dev)
  39 {
  40         struct device *device = wiphy_dev(rt2x00dev->hw->wiphy);
  41         const struct firmware *fw;
  42         char *fw_name;
  43         int retval;
  44         u16 crc;
  45         u16 tmp;
  46
  47         /*
  48          * Read correct firmware from harddisk.
  49          */
  50         fw_name = rt2x00dev->ops->lib->get_firmware_name(rt2x00dev);
  51         if (!fw_name) {
  52                 ERROR(rt2x00dev,
  53                       "Invalid firmware filename.\n"
  54                       "Please file bug report to %s.\n", DRV_PROJECT);
  55                 return -EINVAL;
  56         }
  57
  58         INFO(rt2x00dev, "Loading firmware file '%s'.\n", fw_name);
  59
  60         retval = request_firmware(&fw, fw_name, device);
  61         if (retval) {
  62                 ERROR(rt2x00dev, "Failed to request Firmware.\n");
  63                 return retval;
  64         }
  65
  66         if (!fw || !fw->size || !fw->data) {
  67                 ERROR(rt2x00dev, "Failed to read Firmware.\n");
  68                 return -ENOENT;
  69         }
  70
  71         /*
  72          * Validate the firmware using 16 bit CRC.
  73          * The last 2 bytes of the firmware are the CRC
  74          * so substract those 2 bytes from the CRC checksum,
  75          * and set those 2 bytes to 0 when calculating CRC.
  76          */
  77         tmp = 0;
  78         crc = crc_itu_t(0, fw->data, fw->size - 2);
  79         crc = crc_itu_t(crc, (u8 *)&tmp, 2);
  80
  81         if (crc != (fw->data[fw->size - 2] << 8 | fw->data[fw->size - 1])) {
  82                 ERROR(rt2x00dev, "Firmware CRC error.\n");
  83                 retval = -ENOENT;
  84                 goto exit;
  85         }
  86
  87         INFO(rt2x00dev, "Firmware detected - version: %d.%d.\n",
  88              fw->data[fw->size - 4], fw->data[fw->size - 3]);
  89
  90         rt2x00dev->fw = fw;
  91
  92         return 0;
  93
  94 exit:
  95         release_firmware(fw);
  96
  97         return retval;
  98 }
  99
 100 int rt2x00lib_load_firmware(struct rt2x00_dev *rt2x00dev)
 101 {
 102         int retval;
 103
 104         if (!rt2x00dev->fw) {
 105                 retval = rt2x00lib_request_firmware(rt2x00dev);
 106                 if (retval)
 107                         return retval;
 108         }
 109
 110         /*
 111          * Send firmware to the device.
 112          */
 113         retval = rt2x00dev->ops->lib->load_firmware(rt2x00dev,
 114                                                     rt2x00dev->fw->data,
 115                                                     rt2x00dev->fw->size);
 116         return retval;
 117 }
 118
 119 void rt2x00lib_free_firmware(struct rt2x00_dev *rt2x00dev)
 120 {
 121         release_firmware(rt2x00dev->fw);
 122         rt2x00dev->fw = NULL;
 123 }
 124