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diff -uprN linux-2.6.23.orig/drivers/i2c/chips/eeprom.c linux-2.6.23/drivers/i2c/chips/eeprom.c
--- linux-2.6.23.orig/drivers/i2c/chips/eeprom.c 2007-10-09 15:31:38.000000000 -0500
+++ linux-2.6.23/drivers/i2c/chips/eeprom.c 2007-10-11 00:57:25.000000000 -0500
@@ -33,6 +33,8 @@
#include <linux/jiffies.h>
#include <linux/i2c.h>
#include <linux/mutex.h>
+#include <linux/notifier.h>
+#include <linux/eeprom.h>
/* Addresses to scan */
static unsigned short normal_i2c[] = { 0x50, 0x51, 0x52, 0x53, 0x54,
@@ -41,26 +43,7 @@ static unsigned short normal_i2c[] = { 0
/* Insmod parameters */
I2C_CLIENT_INSMOD_1(eeprom);
-
-/* Size of EEPROM in bytes */
-#define EEPROM_SIZE 256
-
-/* possible types of eeprom devices */
-enum eeprom_nature {
- UNKNOWN,
- VAIO,
-};
-
-/* Each client has this additional data */
-struct eeprom_data {
- struct i2c_client client;
- struct mutex update_lock;
- u8 valid; /* bitfield, bit!=0 if slice is valid */
- unsigned long last_updated[8]; /* In jiffies, 8 slices */
- u8 data[EEPROM_SIZE]; /* Register values */
- enum eeprom_nature nature;
-};
-
+ATOMIC_NOTIFIER_HEAD(eeprom_chain);
static int eeprom_attach_adapter(struct i2c_adapter *adapter);
static int eeprom_detect(struct i2c_adapter *adapter, int address, int kind);
@@ -191,6 +174,7 @@ static int eeprom_detect(struct i2c_adap
data->valid = 0;
mutex_init(&data->update_lock);
data->nature = UNKNOWN;
+ data->attr = &eeprom_attr;
/* Tell the I2C layer a new client has arrived */
if ((err = i2c_attach_client(new_client)))
@@ -214,6 +198,9 @@ static int eeprom_detect(struct i2c_adap
if (err)
goto exit_detach;
+ /* call the notifier chain */
+ atomic_notifier_call_chain(&eeprom_chain, EEPROM_REGISTER, data);
+
return 0;
exit_detach:
@@ -239,6 +226,41 @@ static int eeprom_detach_client(struct i
return 0;
}
+/**
+ * register_eeprom_notifier - register a 'user' of EEPROM devices.
+ * @nb: pointer to notifier info structure
+ *
+ * Registers a callback function to be called upon detection
+ * of an EEPROM device. Detection invokes the 'add' callback
+ * with the kobj of the mutex and a bin_attribute which allows
+ * read from the EEPROM. The intention is that the notifier
+ * will be able to read system configuration from the notifier.
+ *
+ * Only EEPROMs detected *after* the addition of the notifier
+ * are notified. I.e. EEPROMs already known to the system
+ * will not be notified - add the notifier from board level
+ * code!
+ */
+int register_eeprom_notifier(struct notifier_block *nb)
+{
+ return atomic_notifier_chain_register(&eeprom_chain, nb);
+}
+
+/**
+ * unregister_eeprom_notifier - unregister a 'user' of EEPROM devices.
+ * @old: pointer to notifier info structure
+ *
+ * Removes a callback function from the list of 'users' to be
+ * notified upon detection of EEPROM devices.
+ */
+int unregister_eeprom_notifier(struct notifier_block *nb)
+{
+ return atomic_notifier_chain_unregister(&eeprom_chain, nb);
+}
+
+EXPORT_SYMBOL_GPL(register_eeprom_notifier);
+EXPORT_SYMBOL_GPL(unregister_eeprom_notifier);
+
static int __init eeprom_init(void)
{
return i2c_add_driver(&eeprom_driver);
diff -uprN linux-2.6.23.orig/include/linux/eeprom.h linux-2.6.23/include/linux/eeprom.h
--- linux-2.6.23.orig/include/linux/eeprom.h 1969-12-31 18:00:00.000000000 -0600
+++ linux-2.6.23/include/linux/eeprom.h 2007-10-11 00:57:25.000000000 -0500
@@ -0,0 +1,71 @@
+#ifndef _LINUX_EEPROM_H
+#define _LINUX_EEPROM_H
+/*
+ * EEPROM notifier header
+ *
+ * Copyright (C) 2006 John Bowler
+ */
+
+/*
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
+ */
+
+#ifndef __KERNEL__
+#error This is a kernel header
+#endif
+
+#include <linux/list.h>
+#include <linux/kobject.h>
+#include <linux/sysfs.h>
+
+/* Size of EEPROM in bytes */
+#define EEPROM_SIZE 256
+
+/* possible types of eeprom devices */
+enum eeprom_nature {
+ UNKNOWN,
+ VAIO,
+};
+
+/* Each client has this additional data */
+struct eeprom_data {
+ struct i2c_client client;
+ struct mutex update_lock;
+ u8 valid; /* bitfield, bit!=0 if slice is valid */
+ unsigned long last_updated[8]; /* In jiffies, 8 slices */
+ u8 data[EEPROM_SIZE]; /* Register values */
+ enum eeprom_nature nature;
+ struct bin_attribute *attr;
+};
+
+/*
+ * This is very basic.
+ *
+ * If an EEPROM is detected on the I2C bus (this only works for
+ * I2C EEPROMs) the notifier chain is called with
+ * both the I2C information and the kobject for the sysfs
+ * device which has been registers. It is then possible to
+ * read from the device via the bin_attribute::read method
+ * to extract configuration information.
+ *
+ * Register the notifier in the board level code, there is no
+ * need to unregister it but you can if you want (it will save
+ * a little bit or kernel memory to do so).
+ */
+
+extern int register_eeprom_notifier(struct notifier_block *nb);
+extern int unregister_eeprom_notifier(struct notifier_block *nb);
+
+#endif /* _LINUX_EEPROM_H */
diff -uprN linux-2.6.23.orig/include/linux/notifier.h linux-2.6.23/include/linux/notifier.h
--- linux-2.6.23.orig/include/linux/notifier.h 2007-10-09 15:31:38.000000000 -0500
+++ linux-2.6.23/include/linux/notifier.h 2007-10-11 00:57:25.000000000 -0500
@@ -231,5 +231,8 @@ static inline int notifier_to_errno(int
#define PM_SUSPEND_PREPARE 0x0003 /* Going to suspend the system */
#define PM_POST_SUSPEND 0x0004 /* Suspend finished */
+/* eeprom notifier chain */
+#define EEPROM_REGISTER 0x0001
+
#endif /* __KERNEL__ */
#endif /* _LINUX_NOTIFIER_H */
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