ChangeSet 1.2329.2.6, 2005/01/14 14:43:10-08:00, khali at linux-fr.org
[PATCH] I2C: Cleanups to the eeprom driver
Here comes a cleanup patch to the i2c eeprom client driver:
* Get rid of the unused i2c_client client_id.
* Get rid of the redundant non-ISA bus check.
* Fix the adapter capability check. We were previously using
capabilities without checking if they were supported. Document
which capabilities are required and which are optional.
* Reorder things a bit. In particular, wait to have a valid client
before we bother checking if this is a Vaio EEPROM.
* Use strlcpy instead of strncpy, because I Heard It Was Better (TM) and
all other chip drivers use it.
* Take benefit of the auto-increment feature of EEPROMs to speed up the
Vaio check.
* Display an information message when a Vaio EEPROM is detected.
Tested successfully on my laptop, which happens to be a Vaio.
Signed-off-by: Jean Delvare <khali at linux-fr.org>
Signed-off-by: Greg Kroah-Hartman <greg at kroah.com>
drivers/i2c/chips/eeprom.c | 47 +++++++++++++++++++++------------------------
1 files changed, 22 insertions(+), 25 deletions(-)
diff -Nru a/drivers/i2c/chips/eeprom.c b/drivers/i2c/chips/eeprom.c
--- a/drivers/i2c/chips/eeprom.c 2005-01-17 13:20:34 -08:00
+++ b/drivers/i2c/chips/eeprom.c 2005-01-17 13:20:34 -08:00
@@ -78,8 +78,6 @@
.detach_client = eeprom_detach_client,
};
-static int eeprom_id;
-
static void eeprom_update_client(struct i2c_client *client, u8 slice)
{
struct eeprom_data *data = i2c_get_clientdata(client);
@@ -165,16 +163,14 @@
struct eeprom_data *data;
int err = 0;
- /* Make sure we aren't probing the ISA bus!! This is just a safety check
- at this moment; i2c_detect really won't call us. */
-#ifdef DEBUG
- if (i2c_is_isa_adapter(adapter)) {
- dev_dbg(&adapter->dev, " eeprom_detect called for an ISA bus adapter?!?\n");
- return 0;
- }
-#endif
-
- if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE_DATA))
+ /* 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;
/* OK. For now, we presume we have a valid client. We now create the
@@ -197,26 +193,27 @@
/* prevent 24RF08 corruption */
i2c_smbus_write_quick(new_client, 0);
- data->nature = UNKNOWN;
- /* Detect the Vaio nature of EEPROMs.
- We use the "PCG-" prefix as the signature. */
- if (address == 0x57) {
- if (i2c_smbus_read_byte_data(new_client, 0x80) == 'P' &&
- i2c_smbus_read_byte_data(new_client, 0x81) == 'C' &&
- i2c_smbus_read_byte_data(new_client, 0x82) == 'G' &&
- i2c_smbus_read_byte_data(new_client, 0x83) == '-')
- data->nature = VAIO;
- }
-
/* Fill in the remaining client fields */
- strncpy(new_client->name, "eeprom", I2C_NAME_SIZE);
- new_client->id = eeprom_id++;
+ strlcpy(new_client->name, "eeprom", I2C_NAME_SIZE);
data->valid = 0;
init_MUTEX(&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-" prefix as the signature. */
+ if (address == 0x57) {
+ if (i2c_smbus_read_byte_data(new_client, 0x80) == 'P'
+ && i2c_smbus_read_byte(new_client) == 'C'
+ && i2c_smbus_read_byte(new_client) == 'G'
+ && i2c_smbus_read_byte(new_client) == '-')
+ dev_info(&new_client->dev, "Vaio EEPROM detected, "
+ "enabling password protection\n");
+ data->nature = VAIO;
+ }
/* create the sysfs eeprom file */
sysfs_create_bin_file(&new_client->dev.kobj, &eeprom_attr);
