diff options
| -rw-r--r-- | Documentation/i2c/chips/pca9539 | 10 | ||||
| -rw-r--r-- | drivers/i2c/chips/pca9539.c | 109 |
2 files changed, 42 insertions, 77 deletions
diff --git a/Documentation/i2c/chips/pca9539 b/Documentation/i2c/chips/pca9539 index 1d81c53..6aff890 100644 --- a/Documentation/i2c/chips/pca9539 +++ b/Documentation/i2c/chips/pca9539 @@ -7,7 +7,7 @@ drivers/gpio/pca9539.c instead. Supported chips: * Philips PCA9539 Prefix: 'pca9539' - Addresses scanned: 0x74 - 0x77 + Addresses scanned: none Datasheet: http://www.semiconductors.philips.com/acrobat/datasheets/PCA9539_2.pdf @@ -23,6 +23,14 @@ The input sense can also be inverted. The 16 lines are split between two bytes. +Detection +--------- + +The PCA9539 is difficult to detect and not commonly found in PC machines, +so you have to pass the I2C bus and address of the installed PCA9539 +devices explicitly to the driver at load time via the force=... parameter. + + Sysfs entries ------------- diff --git a/drivers/i2c/chips/pca9539.c b/drivers/i2c/chips/pca9539.c index 58ab7f2..270de4e 100644 --- a/drivers/i2c/chips/pca9539.c +++ b/drivers/i2c/chips/pca9539.c @@ -14,8 +14,8 @@ #include <linux/i2c.h> #include <linux/hwmon-sysfs.h> -/* Addresses to scan */ -static unsigned short normal_i2c[] = {0x74, 0x75, 0x76, 0x77, I2C_CLIENT_END}; +/* Addresses to scan: none, device is not autodetected */ +static const unsigned short normal_i2c[] = { I2C_CLIENT_END }; /* Insmod parameters */ I2C_CLIENT_INSMOD_1(pca9539); @@ -32,23 +32,6 @@ enum pca9539_cmd PCA9539_DIRECTION_1 = 7, }; -static int pca9539_attach_adapter(struct i2c_adapter *adapter); -static int pca9539_detect(struct i2c_adapter *adapter, int address, int kind); -static int pca9539_detach_client(struct i2c_client *client); - -/* This is the driver that will be inserted */ -static struct i2c_driver pca9539_driver = { - .driver = { - .name = "pca9539", - }, - .attach_adapter = pca9539_attach_adapter, - .detach_client = pca9539_detach_client, -}; - -struct pca9539_data { - struct i2c_client client; -}; - /* following are the sysfs callback functions */ static ssize_t pca9539_show(struct device *dev, struct device_attribute *attr, char *buf) @@ -105,77 +88,51 @@ static struct attribute_group pca9539_defattr_group = { .attrs = pca9539_attributes, }; -static int pca9539_attach_adapter(struct i2c_adapter *adapter) +/* Return 0 if detection is successful, -ENODEV otherwise */ +static int pca9539_detect(struct i2c_client *client, int kind, + struct i2c_board_info *info) { - return i2c_probe(adapter, &addr_data, pca9539_detect); -} - -/* This function is called by i2c_probe */ -static int pca9539_detect(struct i2c_adapter *adapter, int address, int kind) -{ - struct i2c_client *client; - struct pca9539_data *data; - int err = 0; + struct i2c_adapter *adapter = client->adapter; if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE_DATA)) - goto exit; - - /* OK. For now, we presume we have a valid client. We now create the - client structure, even though we cannot fill it completely yet. */ - if (!(data = kzalloc(sizeof(struct pca9539_data), GFP_KERNEL))) { - err = -ENOMEM; - goto exit; - } - - client = &data->client; - i2c_set_clientdata(client, data); - client->addr = address; - client->adapter = adapter; - client->driver = &pca9539_driver; - - if (kind < 0) { - /* Detection: the pca9539 only has 8 registers (0-7). - A read of 7 should succeed, but a read of 8 should fail. */ - if ((i2c_smbus_read_byte_data(client, 7) < 0) || - (i2c_smbus_read_byte_data(client, 8) >= 0)) - goto exit_kfree; - } - - strlcpy(client->name, "pca9539", I2C_NAME_SIZE); - - /* Tell the I2C layer a new client has arrived */ - if ((err = i2c_attach_client(client))) - goto exit_kfree; + return -ENODEV; - /* Register sysfs hooks */ - err = sysfs_create_group(&client->dev.kobj, - &pca9539_defattr_group); - if (err) - goto exit_detach; + strlcpy(info->type, "pca9539", I2C_NAME_SIZE); return 0; - -exit_detach: - i2c_detach_client(client); -exit_kfree: - kfree(data); -exit: - return err; } -static int pca9539_detach_client(struct i2c_client *client) +static int pca9539_probe(struct i2c_client *client, + const struct i2c_device_id *id) { - int err; + /* Register sysfs hooks */ + return sysfs_create_group(&client->dev.kobj, + &pca9539_defattr_group); +} +static int pca9539_remove(struct i2c_client *client) +{ sysfs_remove_group(&client->dev.kobj, &pca9539_defattr_group); - - if ((err = i2c_detach_client(client))) - return err; - - kfree(i2c_get_clientdata(client)); return 0; } +static const struct i2c_device_id pca9539_id[] = { + { "pca9539", 0 }, + { } +}; + +static struct i2c_driver pca9539_driver = { + .driver = { + .name = "pca9539", + }, + .probe = pca9539_probe, + .remove = pca9539_remove, + .id_table = pca9539_id, + + .detect = pca9539_detect, + .address_data = &addr_data, +}; + static int __init pca9539_init(void) { return i2c_add_driver(&pca9539_driver); |
