]> pilppa.org Git - linux-2.6-omap-h63xx.git/blobdiff - drivers/i2c/chips/eeprom.c
Merge branch 'at91' into devel
[linux-2.6-omap-h63xx.git] / drivers / i2c / chips / eeprom.c
index 7dee001e5133bc7df391bc187e28ae082b9315d2..2c27193aeaa04721ee3159a279e4925abf28edd5 100644 (file)
@@ -1,15 +1,9 @@
 /*
-    eeprom.c - Part of lm_sensors, Linux kernel modules for hardware
-               monitoring
     Copyright (C) 1998, 1999  Frodo Looijaard <frodol@dds.nl> and
                               Philip Edelbrock <phil@netroedge.com>
     Copyright (C) 2003 Greg Kroah-Hartman <greg@kroah.com>
     Copyright (C) 2003 IBM Corp.
-
-    2004-01-16  Jean Delvare <khali@linux-fr.org>
-    Divide the eeprom in 32-byte (arbitrary) slices. This significantly
-    speeds sensors up, as well as various scripts using the eeprom
-    module.
+    Copyright (C) 2004 Jean Delvare <khali@linux-fr.org>
 
     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
@@ -53,7 +47,6 @@ enum eeprom_nature {
 
 /* 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 */
@@ -62,23 +55,10 @@ struct eeprom_data {
 };
 
 
-static int eeprom_attach_adapter(struct i2c_adapter *adapter);
-static int eeprom_detect(struct i2c_adapter *adapter, int address, int kind);
-static int eeprom_detach_client(struct i2c_client *client);
-
-/* This is the driver that will be inserted */
-static struct i2c_driver eeprom_driver = {
-       .driver = {
-               .name   = "eeprom",
-       },
-       .attach_adapter = eeprom_attach_adapter,
-       .detach_client  = eeprom_detach_client,
-};
-
 static void eeprom_update_client(struct i2c_client *client, u8 slice)
 {
        struct eeprom_data *data = i2c_get_clientdata(client);
-       int i, j;
+       int i;
 
        mutex_lock(&data->update_lock);
 
@@ -93,15 +73,12 @@ static void eeprom_update_client(struct i2c_client *client, u8 slice)
                                                        != 32)
                                        goto exit;
                } else {
-                       if (i2c_smbus_write_byte(client, slice << 5)) {
-                               dev_dbg(&client->dev, "eeprom read start has failed!\n");
-                               goto exit;
-                       }
-                       for (i = slice << 5; i < (slice + 1) << 5; i++) {
-                               j = i2c_smbus_read_byte(client);
-                               if (j < 0)
+                       for (i = slice << 5; i < (slice + 1) << 5; i += 2) {
+                               int word = i2c_smbus_read_word_data(client, i);
+                               if (word < 0)
                                        goto exit;
-                               data->data[i] = (u8) j;
+                               data->data[i] = word & 0xff;
+                               data->data[i + 1] = word >> 8;
                        }
                }
                data->last_updated[slice] = jiffies;
@@ -157,98 +134,108 @@ static struct bin_attribute eeprom_attr = {
        .read = eeprom_read,
 };
 
-static int eeprom_attach_adapter(struct i2c_adapter *adapter)
+/* Return 0 if detection is successful, -ENODEV otherwise */
+static int eeprom_detect(struct i2c_client *client, int kind,
+                        struct i2c_board_info *info)
 {
-       return i2c_probe(adapter, &addr_data, eeprom_detect);
+       struct i2c_adapter *adapter = client->adapter;
+
+       /* EDID EEPROMs are often 24C00 EEPROMs, which answer to all
+          addresses 0x50-0x57, but we only care about 0x50. So decline
+          attaching to addresses >= 0x51 on DDC buses */
+       if (!(adapter->class & I2C_CLASS_SPD) && client->addr >= 0x51)
+               return -ENODEV;
+
+       /* There are four ways we can read the EEPROM data:
+          (1) I2C block reads (faster, but unsupported by most adapters)
+          (2) Word reads (128% overhead)
+          (3) Consecutive byte reads (88% overhead, unsafe)
+          (4) Regular byte data reads (265% overhead)
+          The third and fourth methods are not implemented by this driver
+          because all known adapters support one of the first two. */
+       if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_READ_WORD_DATA)
+        && !i2c_check_functionality(adapter, I2C_FUNC_SMBUS_READ_I2C_BLOCK))
+               return -ENODEV;
+
+       strlcpy(info->type, "eeprom", I2C_NAME_SIZE);
+
+       return 0;
 }
 
-/* This function is called by i2c_probe */
-static int eeprom_detect(struct i2c_adapter *adapter, int address, int kind)
+static int eeprom_probe(struct i2c_client *client,
+                       const struct i2c_device_id *id)
 {
-       struct i2c_client *new_client;
+       struct i2c_adapter *adapter = client->adapter;
        struct eeprom_data *data;
-       int err = 0;
-
-       /* There are three ways we can read the EEPROM data:
-          (1) I2C block reads (faster, but unsupported by most adapters)
-          (2) Consecutive byte reads (100% overhead)
-          (3) Regular byte data reads (200% overhead)
-          The third method is not implemented by this driver because all
-          known adapters support at least the second. */
-       if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_READ_BYTE_DATA
-                                           | I2C_FUNC_SMBUS_BYTE))
-               goto exit;
+       int err;
 
        if (!(data = kzalloc(sizeof(struct eeprom_data), GFP_KERNEL))) {
                err = -ENOMEM;
                goto exit;
        }
 
-       new_client = &data->client;
        memset(data->data, 0xff, EEPROM_SIZE);
-       i2c_set_clientdata(new_client, data);
-       new_client->addr = address;
-       new_client->adapter = adapter;
-       new_client->driver = &eeprom_driver;
-       new_client->flags = 0;
-
-       /* Fill in the remaining client fields */
-       strlcpy(new_client->name, "eeprom", I2C_NAME_SIZE);
-       data->valid = 0;
+       i2c_set_clientdata(client, data);
        mutex_init(&data->update_lock);
        data->nature = UNKNOWN;
 
-       /* Tell the I2C layer a new client has arrived */
-       if ((err = i2c_attach_client(new_client)))
-               goto exit_kfree;
-
        /* Detect the Vaio nature of EEPROMs.
           We use the "PCG-" or "VGN-" prefix as the signature. */
-       if (address == 0x57) {
+       if (client->addr == 0x57
+        && i2c_check_functionality(adapter, I2C_FUNC_SMBUS_READ_BYTE_DATA)) {
                char name[4];
 
-               name[0] = i2c_smbus_read_byte_data(new_client, 0x80);
-               name[1] = i2c_smbus_read_byte(new_client);
-               name[2] = i2c_smbus_read_byte(new_client);
-               name[3] = i2c_smbus_read_byte(new_client);
+               name[0] = i2c_smbus_read_byte_data(client, 0x80);
+               name[1] = i2c_smbus_read_byte_data(client, 0x81);
+               name[2] = i2c_smbus_read_byte_data(client, 0x82);
+               name[3] = i2c_smbus_read_byte_data(client, 0x83);
 
                if (!memcmp(name, "PCG-", 4) || !memcmp(name, "VGN-", 4)) {
-                       dev_info(&new_client->dev, "Vaio EEPROM detected, "
+                       dev_info(&client->dev, "Vaio EEPROM detected, "
                                 "enabling privacy protection\n");
                        data->nature = VAIO;
                }
        }
 
        /* create the sysfs eeprom file */
-       err = sysfs_create_bin_file(&new_client->dev.kobj, &eeprom_attr);
+       err = sysfs_create_bin_file(&client->dev.kobj, &eeprom_attr);
        if (err)
-               goto exit_detach;
+               goto exit_kfree;
 
        return 0;
 
-exit_detach:
-       i2c_detach_client(new_client);
 exit_kfree:
        kfree(data);
 exit:
        return err;
 }
 
-static int eeprom_detach_client(struct i2c_client *client)
+static int eeprom_remove(struct i2c_client *client)
 {
-       int err;
-
        sysfs_remove_bin_file(&client->dev.kobj, &eeprom_attr);
-
-       err = i2c_detach_client(client);
-       if (err)
-               return err;
-
        kfree(i2c_get_clientdata(client));
 
        return 0;
 }
 
+static const struct i2c_device_id eeprom_id[] = {
+       { "eeprom", 0 },
+       { }
+};
+
+static struct i2c_driver eeprom_driver = {
+       .driver = {
+               .name   = "eeprom",
+       },
+       .probe          = eeprom_probe,
+       .remove         = eeprom_remove,
+       .id_table       = eeprom_id,
+
+       .class          = I2C_CLASS_DDC | I2C_CLASS_SPD,
+       .detect         = eeprom_detect,
+       .address_data   = &addr_data,
+};
+
 static int __init eeprom_init(void)
 {
        return i2c_add_driver(&eeprom_driver);