diff options
Diffstat (limited to 'drivers/hwmon/ucd9200.c')
| -rw-r--r-- | drivers/hwmon/ucd9200.c | 210 |
1 files changed, 210 insertions, 0 deletions
diff --git a/drivers/hwmon/ucd9200.c b/drivers/hwmon/ucd9200.c new file mode 100644 index 000000000000..ffcc1cf3609d --- /dev/null +++ b/drivers/hwmon/ucd9200.c @@ -0,0 +1,210 @@ +/* + * Hardware monitoring driver for ucd9200 series Digital PWM System Controllers + * + * Copyright (C) 2011 Ericsson AB. + * + * 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 <linux/kernel.h> +#include <linux/module.h> +#include <linux/init.h> +#include <linux/err.h> +#include <linux/slab.h> +#include <linux/i2c.h> +#include <linux/i2c/pmbus.h> +#include "pmbus.h" + +#define UCD9200_PHASE_INFO 0xd2 +#define UCD9200_DEVICE_ID 0xfd + +enum chips { ucd9200, ucd9220, ucd9222, ucd9224, ucd9240, ucd9244, ucd9246, + ucd9248 }; + +static const struct i2c_device_id ucd9200_id[] = { + {"ucd9200", ucd9200}, + {"ucd9220", ucd9220}, + {"ucd9222", ucd9222}, + {"ucd9224", ucd9224}, + {"ucd9240", ucd9240}, + {"ucd9244", ucd9244}, + {"ucd9246", ucd9246}, + {"ucd9248", ucd9248}, + {} +}; +MODULE_DEVICE_TABLE(i2c, ucd9200_id); + +static int ucd9200_probe(struct i2c_client *client, + const struct i2c_device_id *id) +{ + u8 block_buffer[I2C_SMBUS_BLOCK_MAX + 1]; + struct pmbus_driver_info *info; + const struct i2c_device_id *mid; + int i, j, ret; + + if (!i2c_check_functionality(client->adapter, + I2C_FUNC_SMBUS_BYTE_DATA | + I2C_FUNC_SMBUS_BLOCK_DATA)) + return -ENODEV; + + ret = i2c_smbus_read_block_data(client, UCD9200_DEVICE_ID, + block_buffer); + if (ret < 0) { + dev_err(&client->dev, "Failed to read device ID\n"); + return ret; + } + block_buffer[ret] = '\0'; + dev_info(&client->dev, "Device ID %s\n", block_buffer); + + mid = NULL; + for (i = 0; i < ARRAY_SIZE(ucd9200_id); i++) { + mid = &ucd9200_id[i]; + if (!strncasecmp(mid->name, block_buffer, strlen(mid->name))) + break; + } + if (!mid || !strlen(mid->name)) { + dev_err(&client->dev, "Unsupported device\n"); + return -ENODEV; + } + if (id->driver_data != ucd9200 && id->driver_data != mid->driver_data) + dev_notice(&client->dev, + "Device mismatch: Configured %s, detected %s\n", + id->name, mid->name); + + info = kzalloc(sizeof(struct pmbus_driver_info), GFP_KERNEL); + if (!info) + return -ENOMEM; + + ret = i2c_smbus_read_block_data(client, UCD9200_PHASE_INFO, + block_buffer); + if (ret < 0) { + dev_err(&client->dev, "Failed to read phase information\n"); + goto out; + } + + /* + * Calculate number of configured pages (rails) from PHASE_INFO + * register. + * Rails have to be sequential, so we can abort after finding + * the first unconfigured rail. + */ + info->pages = 0; + for (i = 0; i < ret; i++) { + if (!block_buffer[i]) + break; + info->pages++; + } + if (!info->pages) { + dev_err(&client->dev, "No rails configured\n"); + ret = -ENODEV; + goto out; + } + dev_info(&client->dev, "%d rails configured\n", info->pages); + + /* + * Set PHASE registers on all pages to 0xff to ensure that phase + * specific commands will apply to all phases of a given page (rail). + * This only affects the READ_IOUT and READ_TEMPERATURE2 registers. + * READ_IOUT will return the sum of currents of all phases of a rail, + * and READ_TEMPERATURE2 will return the maximum temperature detected + * for the the phases of the rail. + */ + for (i = 0; i < info->pages; i++) { + /* + * Setting PAGE & PHASE fails once in a while for no obvious + * reason, so we need to retry a couple of times. + */ + for (j = 0; j < 3; j++) { + ret = i2c_smbus_write_byte_data(client, PMBUS_PAGE, i); + if (ret < 0) + continue; + ret = i2c_smbus_write_byte_data(client, PMBUS_PHASE, + 0xff); + if (ret < 0) + continue; + break; + } + if (ret < 0) { + dev_err(&client->dev, + "Failed to initialize PHASE registers\n"); + goto out; + } + } + if (info->pages > 1) + i2c_smbus_write_byte_data(client, PMBUS_PAGE, 0); + + info->func[0] = PMBUS_HAVE_VIN | PMBUS_HAVE_STATUS_INPUT | + PMBUS_HAVE_IIN | PMBUS_HAVE_PIN | + PMBUS_HAVE_VOUT | PMBUS_HAVE_STATUS_VOUT | + PMBUS_HAVE_IOUT | PMBUS_HAVE_STATUS_IOUT | + PMBUS_HAVE_POUT | PMBUS_HAVE_TEMP | + PMBUS_HAVE_TEMP2 | PMBUS_HAVE_STATUS_TEMP; + + for (i = 1; i < info->pages; i++) + info->func[i] = PMBUS_HAVE_VOUT | PMBUS_HAVE_STATUS_VOUT | + PMBUS_HAVE_IOUT | PMBUS_HAVE_STATUS_IOUT | + PMBUS_HAVE_POUT | + PMBUS_HAVE_TEMP2 | PMBUS_HAVE_STATUS_TEMP; + + /* ucd9240 supports a single fan */ + if (mid->driver_data == ucd9240) + info->func[0] |= PMBUS_HAVE_FAN12 | PMBUS_HAVE_STATUS_FAN12; + + ret = pmbus_do_probe(client, mid, info); + if (ret < 0) + goto out; + return 0; +out: + kfree(info); + return ret; +} + +static int ucd9200_remove(struct i2c_client *client) +{ + int ret; + const struct pmbus_driver_info *info; + + info = pmbus_get_driver_info(client); + ret = pmbus_do_remove(client); + kfree(info); + return ret; +} + + +/* This is the driver that will be inserted */ +static struct i2c_driver ucd9200_driver = { + .driver = { + .name = "ucd9200", + }, + .probe = ucd9200_probe, + .remove = ucd9200_remove, + .id_table = ucd9200_id, +}; + +static int __init ucd9200_init(void) +{ + return i2c_add_driver(&ucd9200_driver); +} + +static void __exit ucd9200_exit(void) +{ + i2c_del_driver(&ucd9200_driver); +} + +MODULE_AUTHOR("Guenter Roeck"); +MODULE_DESCRIPTION("PMBus driver for TI UCD922x, UCD924x"); +MODULE_LICENSE("GPL"); +module_init(ucd9200_init); +module_exit(ucd9200_exit); |