/*
* Hardware monitoring driver for PMBus devices
*
* Copyright (c) 2010, 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/mutex.h>
#include <linux/i2c.h>
#include "pmbus.h"
/*
* Find sensor groups and status registers on each page.
*/
static void pmbus_find_sensor_groups(struct i2c_client *client,
struct pmbus_driver_info *info)
{
int page;
/* Sensors detected on page 0 only */
if (pmbus_check_word_register(client, 0, PMBUS_READ_VIN))
info->func[0] |= PMBUS_HAVE_VIN;
if (pmbus_check_word_register(client, 0, PMBUS_READ_VCAP))
info->func[0] |= PMBUS_HAVE_VCAP;
if (pmbus_check_word_register(client, 0, PMBUS_READ_IIN))
info->func[0] |= PMBUS_HAVE_IIN;
if (pmbus_check_word_register(client, 0, PMBUS_READ_PIN))
info->func[0] |= PMBUS_HAVE_PIN;
if (info->func[0]
&& pmbus_check_byte_register(client, 0, PMBUS_STATUS_INPUT))
info->func[0] |= PMBUS_HAVE_STATUS_INPUT;
if (pmbus_check_word_register(client, 0, PMBUS_READ_FAN_SPEED_1)) {
info->func[0] |= PMBUS_HAVE_FAN12;
if (pmbus_check_byte_register(client, 0, PMBUS_STATUS_FAN_12))
info->func[0] |= PMBUS_HAVE_STATUS_FAN12;
}
if (pmbus_check_word_register(client, 0, PMBUS_READ_FAN_SPEED_3)) {
info->func[0] |= PMBUS_HAVE_FAN34;
if (pmbus_check_byte_register(client, 0, PMBUS_STATUS_FAN_34))
info->func[0] |= PMBUS_HAVE_STATUS_FAN34;
}
if (pmbus_check_word_register(client, 0, PMBUS_READ_TEMPERATURE_1)) {
info->func[0] |= PMBUS_HAVE_TEMP;
if (pmbus_check_byte_register(client, 0,
PMBUS_STATUS_TEMPERATURE))
info->func[0] |= PMBUS_HAVE_STATUS_TEMP;
}
/* Sensors detected on all pages */
for (page = 0; page < info->pages; page++) {
if (pmbus_check_word_register(client, page, PMBUS_READ_VOUT)) {
info->func[page] |= PMBUS_HAVE_VOUT;
if (pmbus_check_byte_register(client, page,
PMBUS_STATUS_VOUT))
info->func[page] |= PMBUS_HAVE_STATUS_VOUT;
}
if (pmbus_check_word_register(client, page, PMBUS_READ_IOUT)) {
info->func[page] |= PMBUS_HAVE_IOUT;
if (pmbus_check_byte_register(client, 0,
PMBUS_STATUS_IOUT))
info->func[page] |= PMBUS_HAVE_STATUS_IOUT;
}
if (pmbus_check_word_register(client, page, PMBUS_READ_POUT))
info->func[page] |= PMBUS_HAVE_POUT;
}
}
/*
* Identify chip parameters.
*/
static int pmbus_identify(struct i2c_client *client,
struct pmbus_driver_info *info)
{
if (!info->pages) {
/*
* Check if the PAGE command is supported. If it is,
* keep setting the page number until it fails or until the
* maximum number of pages has been reached. Assume that
* this is the number of pages supported by the chip.
*/
if (pmbus_check_byte_register(client, 0, PMBUS_PAGE)) {
int page;
for (page = 1; page < PMBUS_PAGES; page++) {
if (pmbus_set_page(client, page) < 0)
break;
}
pmbus_set_page(client, 0);
info->pages = page;
} else {
info->pages = 1;
}
}
/*
* We should check if the COEFFICIENTS register is supported.
* If it is, and the chip is configured for direct mode, we can read
* the coefficients from the chip, one set per group of sensor
* registers.
*
* To do this, we will need access to a chip which actually supports the
* COEFFICIENTS command, since the command is too complex to implement
* without testing it.
*/
/* Try to find sensor groups */
pmbus_find_sensor_groups(client, info);
return 0;
}
static int pmbus_probe(struct i2c_client *client,
const struct i2c_device_id *id)
{
struct pmbus_driver_info *info;
int ret;
info = kzalloc(sizeof(struct pmbus_driver_info), GFP_KERNEL);
if (!info)
return -ENOMEM;
info->pages = id->driver_data;
info->identify = pmbus_identify;
ret = pmbus_do_probe(client, id, info);
if (ret < 0)
goto out;
return 0;
out:
kfree(info);
return ret;
}
static int pmbus_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;
}
/*
* Use driver_data to set the number of pages supported by the chip.
*/
static const struct i2c_device_id pmbus_id[] = {
{"bmr450", 1},
{"bmr451", 1},
{"bmr453", 1},
{"bmr454", 1},
{"ltc2978", 8},
{"pmbus", 0},
{}
};
MODULE_DEVICE_TABLE(i2c, pmbus_id);
/* This is the driver that will be inserted */
static struct i2c_driver pmbus_driver = {
.driver = {
.name = "pmbus",
},
.probe = pmbus_probe,
.remove = pmbus_remove,
.id_table = pmbus_id,
};
static int __init pmbus_init(void)
{
return i2c_add_driver(&pmbus_driver);
}
static void __exit pmbus_exit(void)
{
i2c_del_driver(&pmbus_driver);
}
MODULE_AUTHOR("Guenter Roeck");
MODULE_DESCRIPTION("Generic PMBus driver");
MODULE_LICENSE("GPL");
module_init(pmbus_init);
module_exit(pmbus_exit);
