target/linux/ixp4xx/patches-2.6.25/294-eeprom_new_notifier.patch

   1 Index: linux-2.6.25.4/drivers/i2c/chips/eeprom.c
   2 ===================================================================
   3 --- linux-2.6.25.4.orig/drivers/i2c/chips/eeprom.c
   4 +++ linux-2.6.25.4/drivers/i2c/chips/eeprom.c
   5 @@ -33,6 +33,8 @@
   6  #include <linux/jiffies.h>
   7  #include <linux/i2c.h>
   8  #include <linux/mutex.h>
   9 +#include <linux/notifier.h>
  10 +#include <linux/eeprom.h>
  11
  12  /* Addresses to scan */
  13  static const unsigned short normal_i2c[] = { 0x50, 0x51, 0x52, 0x53, 0x54,
  14 @@ -41,26 +43,7 @@ static const unsigned short normal_i2c[]
  15  /* Insmod parameters */
  16  I2C_CLIENT_INSMOD_1(eeprom);
  17
  18 -
  19 -/* Size of EEPROM in bytes */
  20 -#define EEPROM_SIZE            256
  21 -
  22 -/* possible types of eeprom devices */
  23 -enum eeprom_nature {
  24 -       UNKNOWN,
  25 -       VAIO,
  26 -};
  27 -
  28 -/* Each client has this additional data */
  29 -struct eeprom_data {
  30 -       struct i2c_client client;
  31 -       struct mutex update_lock;
  32 -       u8 valid;                       /* bitfield, bit!=0 if slice is valid */
  33 -       unsigned long last_updated[8];  /* In jiffies, 8 slices */
  34 -       u8 data[EEPROM_SIZE];           /* Register values */
  35 -       enum eeprom_nature nature;
  36 -};
  37 -
  38 +ATOMIC_NOTIFIER_HEAD(eeprom_chain);
  39
  40  static int eeprom_attach_adapter(struct i2c_adapter *adapter);
  41  static int eeprom_detect(struct i2c_adapter *adapter, int address, int kind);
  42 @@ -197,6 +180,7 @@ static int eeprom_detect(struct i2c_adap
  43         data->valid = 0;
  44         mutex_init(&data->update_lock);
  45         data->nature = UNKNOWN;
  46 +       data->attr = &eeprom_attr;
  47
  48         /* Tell the I2C layer a new client has arrived */
  49         if ((err = i2c_attach_client(new_client)))
  50 @@ -224,6 +208,9 @@ static int eeprom_detect(struct i2c_adap
  51         if (err)
  52                 goto exit_detach;
  53
  54 +       /* call the notifier chain */
  55 +       atomic_notifier_call_chain(&eeprom_chain, EEPROM_REGISTER, data);
  56 +
  57         return 0;
  58
  59  exit_detach:
  60 @@ -249,6 +236,41 @@ static int eeprom_detach_client(struct i
  61         return 0;
  62  }
  63
  64 +/**
  65 + * register_eeprom_notifier - register a 'user' of EEPROM devices.
  66 + * @nb: pointer to notifier info structure
  67 + *
  68 + * Registers a callback function to be called upon detection
  69 + * of an EEPROM device.  Detection invokes the 'add' callback
  70 + * with the kobj of the mutex and a bin_attribute which allows
  71 + * read from the EEPROM.  The intention is that the notifier
  72 + * will be able to read system configuration from the notifier.
  73 + *
  74 + * Only EEPROMs detected *after* the addition of the notifier
  75 + * are notified.  I.e. EEPROMs already known to the system
  76 + * will not be notified - add the notifier from board level
  77 + * code!
  78 + */
  79 +int register_eeprom_notifier(struct notifier_block *nb)
  80 +{
  81 +       return atomic_notifier_chain_register(&eeprom_chain, nb);
  82 +}
  83 +
  84 +/**
  85 + *     unregister_eeprom_notifier - unregister a 'user' of EEPROM devices.
  86 + *     @old: pointer to notifier info structure
  87 + *
  88 + *     Removes a callback function from the list of 'users' to be
  89 + *     notified upon detection of EEPROM devices.
  90 + */
  91 +int unregister_eeprom_notifier(struct notifier_block *nb)
  92 +{
  93 +       return atomic_notifier_chain_unregister(&eeprom_chain, nb);
  94 +}
  95 +
  96 +EXPORT_SYMBOL_GPL(register_eeprom_notifier);
  97 +EXPORT_SYMBOL_GPL(unregister_eeprom_notifier);
  98 +
  99  static int __init eeprom_init(void)
 100  {
 101         return i2c_add_driver(&eeprom_driver);
 102 Index: linux-2.6.25.4/include/linux/eeprom.h
 103 ===================================================================
 104 --- /dev/null
 105 +++ linux-2.6.25.4/include/linux/eeprom.h
 106 @@ -0,0 +1,71 @@
 107 +#ifndef _LINUX_EEPROM_H
 108 +#define _LINUX_EEPROM_H
 109 +/*
 110 + *  EEPROM notifier header
 111 + *
 112 + *  Copyright (C) 2006 John Bowler
 113 + */
 114 +
 115 +/*
 116 + * This program is free software; you can redistribute it and/or modify
 117 + * it under the terms of the GNU General Public License as published by
 118 + * the Free Software Foundation; either version 2 of the License, or
 119 + * (at your option) any later version.
 120 + *
 121 + * This program is distributed in the hope that it will be useful,
 122 + * but WITHOUT ANY WARRANTY; without even the implied warranty of
 123 + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 124 + * GNU General Public License for more details.
 125 + *
 126 + * You should have received a copy of the GNU General Public License
 127 + * along with this program; if not, write to the Free Software
 128 + * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
 129 + */
 130 +
 131 +#ifndef __KERNEL__
 132 +#error This is a kernel header
 133 +#endif
 134 +
 135 +#include <linux/list.h>
 136 +#include <linux/kobject.h>
 137 +#include <linux/sysfs.h>
 138 +
 139 +/* Size of EEPROM in bytes */
 140 +#define EEPROM_SIZE             256
 141 +
 142 +/* possible types of eeprom devices */
 143 +enum eeprom_nature {
 144 +       UNKNOWN,
 145 +       VAIO,
 146 +};
 147 +
 148 +/* Each client has this additional data */
 149 +struct eeprom_data {
 150 +       struct i2c_client client;
 151 +       struct mutex update_lock;
 152 +       u8 valid;                       /* bitfield, bit!=0 if slice is valid */
 153 +       unsigned long last_updated[8];  /* In jiffies, 8 slices */
 154 +       u8 data[EEPROM_SIZE];           /* Register values */
 155 +       enum eeprom_nature nature;
 156 +       struct bin_attribute *attr;
 157 +};
 158 +
 159 +/*
 160 + * This is very basic.
 161 + *
 162 + * If an EEPROM is detected on the I2C bus (this only works for
 163 + * I2C EEPROMs) the notifier chain  is called with
 164 + * both the I2C information and the kobject for the sysfs
 165 + * device which has been registers.  It is then possible to
 166 + * read from the device via the bin_attribute::read method
 167 + * to extract configuration information.
 168 + *
 169 + * Register the notifier in the board level code, there is no
 170 + * need to unregister it but you can if you want (it will save
 171 + * a little bit or kernel memory to do so).
 172 + */
 173 +
 174 +extern int register_eeprom_notifier(struct notifier_block *nb);
 175 +extern int unregister_eeprom_notifier(struct notifier_block *nb);
 176 +
 177 +#endif /* _LINUX_EEPROM_H */
 178 Index: linux-2.6.25.4/include/linux/notifier.h
 179 ===================================================================
 180 --- linux-2.6.25.4.orig/include/linux/notifier.h
 181 +++ linux-2.6.25.4/include/linux/notifier.h
 182 @@ -248,5 +248,8 @@ extern struct blocking_notifier_head reb
 183  #define VT_WRITE               0x0003 /* A char got output */
 184  #define VT_UPDATE              0x0004 /* A bigger update occurred */
 185
 186 +/* eeprom notifier chain */
 187 +#define EEPROM_REGISTER                0x0001
 188 +
 189  #endif /* __KERNEL__ */
 190  #endif /* _LINUX_NOTIFIER_H */