/*
* 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);
