/* * An hwmon driver for accton as7816_64x Power Module * * Copyright (C) 2014 Accton Technology Corporation. * Brandon Chuang * * Based on ad7414.c * Copyright 2006 Stefan Roese , DENX Software Engineering * * 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., 675 Mass Ave, Cambridge, MA 02139, USA. */ #include #include #include #include #include #include #include #include #include #include #include #define PSU_STATUS_I2C_ADDR 0x60 #define PSU_STATUS_I2C_REG_OFFSET 0x03 #define IS_POWER_GOOD(id, value) (!!(value & BIT(2+id))) #define IS_PRESENT(id, value) (!(value & BIT(id))) static ssize_t show_status(struct device *dev, struct device_attribute *da, char *buf); static struct as7816_64x_psu_data *as7816_64x_psu_update_device(struct device *dev); extern int accton_i2c_cpld_read (u8 cpld_addr, u8 reg); /* Addresses scanned */ static const unsigned short normal_i2c[] = { I2C_CLIENT_END }; /* Each client has this additional data */ struct as7816_64x_psu_data { struct device *hwmon_dev; struct mutex update_lock; char valid; /* !=0 if registers are valid */ unsigned long last_updated; /* In jiffies */ u8 index; /* PSU index */ u8 status; /* Status(present/power_good) register read from CPLD */ }; enum as7816_64x_psu_sysfs_attributes { PSU_PRESENT, PSU_POWER_GOOD }; /* sysfs attributes for hwmon */ static SENSOR_DEVICE_ATTR(psu_present, S_IRUGO, show_status, NULL, PSU_PRESENT); static SENSOR_DEVICE_ATTR(psu_power_good, S_IRUGO, show_status, NULL, PSU_POWER_GOOD); static struct attribute *as7816_64x_psu_attributes[] = { &sensor_dev_attr_psu_present.dev_attr.attr, &sensor_dev_attr_psu_power_good.dev_attr.attr, NULL }; static ssize_t show_status(struct device *dev, struct device_attribute *da, char *buf) { struct sensor_device_attribute *attr = to_sensor_dev_attr(da); struct as7816_64x_psu_data *data = as7816_64x_psu_update_device(dev); u8 status = 0; if (!data->valid) { return -EIO; } if (attr->index == PSU_PRESENT) { status = IS_PRESENT(data->index, data->status); } else { /* PSU_POWER_GOOD */ status = IS_POWER_GOOD(data->index, data->status); } return sprintf(buf, "%d\n", status); } static const struct attribute_group as7816_64x_psu_group = { .attrs = as7816_64x_psu_attributes, }; static int as7816_64x_psu_probe(struct i2c_client *client, const struct i2c_device_id *dev_id) { struct as7816_64x_psu_data *data; int status; if (!i2c_check_functionality(client->adapter, I2C_FUNC_SMBUS_I2C_BLOCK)) { status = -EIO; goto exit; } data = kzalloc(sizeof(struct as7816_64x_psu_data), GFP_KERNEL); if (!data) { status = -ENOMEM; goto exit; } i2c_set_clientdata(client, data); data->valid = 0; data->index = dev_id->driver_data; mutex_init(&data->update_lock); dev_info(&client->dev, "chip found\n"); /* Register sysfs hooks */ status = sysfs_create_group(&client->dev.kobj, &as7816_64x_psu_group); if (status) { goto exit_free; } data->hwmon_dev = hwmon_device_register(&client->dev); if (IS_ERR(data->hwmon_dev)) { status = PTR_ERR(data->hwmon_dev); goto exit_remove; } dev_info(&client->dev, "%s: psu '%s'\n", dev_name(data->hwmon_dev), client->name); return 0; exit_remove: sysfs_remove_group(&client->dev.kobj, &as7816_64x_psu_group); exit_free: kfree(data); exit: return status; } static int as7816_64x_psu_remove(struct i2c_client *client) { struct as7816_64x_psu_data *data = i2c_get_clientdata(client); hwmon_device_unregister(data->hwmon_dev); sysfs_remove_group(&client->dev.kobj, &as7816_64x_psu_group); kfree(data); return 0; } enum psu_index { as7816_64x_psu1, as7816_64x_psu2 }; static const struct i2c_device_id as7816_64x_psu_id[] = { { "as7816_64x_psu1", as7816_64x_psu1 }, { "as7816_64x_psu2", as7816_64x_psu2 }, {} }; MODULE_DEVICE_TABLE(i2c, as7816_64x_psu_id); static struct i2c_driver as7816_64x_psu_driver = { .class = I2C_CLASS_HWMON, .driver = { .name = "as7816_64x_psu", }, .probe = as7816_64x_psu_probe, .remove = as7816_64x_psu_remove, .id_table = as7816_64x_psu_id, .address_list = normal_i2c, }; static struct as7816_64x_psu_data *as7816_64x_psu_update_device(struct device *dev) { struct i2c_client *client = to_i2c_client(dev); struct as7816_64x_psu_data *data = i2c_get_clientdata(client); mutex_lock(&data->update_lock); if (time_after(jiffies, data->last_updated + HZ + HZ / 2) || !data->valid) { int status; data->valid = 0; dev_dbg(&client->dev, "Starting as7816_64x update\n"); /* Read psu status */ status = accton_i2c_cpld_read(PSU_STATUS_I2C_ADDR, PSU_STATUS_I2C_REG_OFFSET); if (status < 0) { dev_dbg(&client->dev, "cpld reg (0x%x) err %d\n", PSU_STATUS_I2C_ADDR, status); goto exit; } else { data->status = status; } data->last_updated = jiffies; data->valid = 1; } exit: mutex_unlock(&data->update_lock); return data; } static int __init as7816_64x_psu_init(void) { return i2c_add_driver(&as7816_64x_psu_driver); } static void __exit as7816_64x_psu_exit(void) { i2c_del_driver(&as7816_64x_psu_driver); } module_init(as7816_64x_psu_init); module_exit(as7816_64x_psu_exit); MODULE_AUTHOR("Brandon Chuang "); MODULE_DESCRIPTION("as7816_64x_psu driver"); MODULE_LICENSE("GPL");