diff options
Diffstat (limited to 'drivers/i2c/chips/pca9539.c')
| -rw-r--r-- | drivers/i2c/chips/pca9539.c | 152 |
1 files changed, 152 insertions, 0 deletions
diff --git a/drivers/i2c/chips/pca9539.c b/drivers/i2c/chips/pca9539.c new file mode 100644 index 0000000..270de4e --- /dev/null +++ b/drivers/i2c/chips/pca9539.c @@ -0,0 +1,152 @@ +/* + pca9539.c - 16-bit I/O port with interrupt and reset + + Copyright (C) 2005 Ben Gardner <bgardner@wabtec.com> + + 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; version 2 of the License. +*/ + +#include <linux/module.h> +#include <linux/init.h> +#include <linux/slab.h> +#include <linux/i2c.h> +#include <linux/hwmon-sysfs.h> + +/* Addresses to scan: none, device is not autodetected */ +static const unsigned short normal_i2c[] = { I2C_CLIENT_END }; + +/* Insmod parameters */ +I2C_CLIENT_INSMOD_1(pca9539); + +enum pca9539_cmd +{ + PCA9539_INPUT_0 = 0, + PCA9539_INPUT_1 = 1, + PCA9539_OUTPUT_0 = 2, + PCA9539_OUTPUT_1 = 3, + PCA9539_INVERT_0 = 4, + PCA9539_INVERT_1 = 5, + PCA9539_DIRECTION_0 = 6, + PCA9539_DIRECTION_1 = 7, +}; + +/* following are the sysfs callback functions */ +static ssize_t pca9539_show(struct device *dev, struct device_attribute *attr, + char *buf) +{ + struct sensor_device_attribute *psa = to_sensor_dev_attr(attr); + struct i2c_client *client = to_i2c_client(dev); + return sprintf(buf, "%d\n", i2c_smbus_read_byte_data(client, + psa->index)); +} + +static ssize_t pca9539_store(struct device *dev, struct device_attribute *attr, + const char *buf, size_t count) +{ + struct sensor_device_attribute *psa = to_sensor_dev_attr(attr); + struct i2c_client *client = to_i2c_client(dev); + unsigned long val = simple_strtoul(buf, NULL, 0); + if (val > 0xff) + return -EINVAL; + i2c_smbus_write_byte_data(client, psa->index, val); + return count; +} + +/* Define the device attributes */ + +#define PCA9539_ENTRY_RO(name, cmd_idx) \ + static SENSOR_DEVICE_ATTR(name, S_IRUGO, pca9539_show, NULL, cmd_idx) + +#define PCA9539_ENTRY_RW(name, cmd_idx) \ + static SENSOR_DEVICE_ATTR(name, S_IRUGO | S_IWUSR, pca9539_show, \ + pca9539_store, cmd_idx) + +PCA9539_ENTRY_RO(input0, PCA9539_INPUT_0); +PCA9539_ENTRY_RO(input1, PCA9539_INPUT_1); +PCA9539_ENTRY_RW(output0, PCA9539_OUTPUT_0); +PCA9539_ENTRY_RW(output1, PCA9539_OUTPUT_1); +PCA9539_ENTRY_RW(invert0, PCA9539_INVERT_0); +PCA9539_ENTRY_RW(invert1, PCA9539_INVERT_1); +PCA9539_ENTRY_RW(direction0, PCA9539_DIRECTION_0); +PCA9539_ENTRY_RW(direction1, PCA9539_DIRECTION_1); + +static struct attribute *pca9539_attributes[] = { + &sensor_dev_attr_input0.dev_attr.attr, + &sensor_dev_attr_input1.dev_attr.attr, + &sensor_dev_attr_output0.dev_attr.attr, + &sensor_dev_attr_output1.dev_attr.attr, + &sensor_dev_attr_invert0.dev_attr.attr, + &sensor_dev_attr_invert1.dev_attr.attr, + &sensor_dev_attr_direction0.dev_attr.attr, + &sensor_dev_attr_direction1.dev_attr.attr, + NULL +}; + +static struct attribute_group pca9539_defattr_group = { + .attrs = pca9539_attributes, +}; + +/* Return 0 if detection is successful, -ENODEV otherwise */ +static int pca9539_detect(struct i2c_client *client, int kind, + struct i2c_board_info *info) +{ + struct i2c_adapter *adapter = client->adapter; + + if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE_DATA)) + return -ENODEV; + + strlcpy(info->type, "pca9539", I2C_NAME_SIZE); + + return 0; +} + +static int pca9539_probe(struct i2c_client *client, + const struct i2c_device_id *id) +{ + /* 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); + 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); +} + +static void __exit pca9539_exit(void) +{ + i2c_del_driver(&pca9539_driver); +} + +MODULE_AUTHOR("Ben Gardner <bgardner@wabtec.com>"); +MODULE_DESCRIPTION("PCA9539 driver"); +MODULE_LICENSE("GPL"); + +module_init(pca9539_init); +module_exit(pca9539_exit); + |
