You can not select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
135 lines
3.2 KiB
135 lines
3.2 KiB
/*
|
|
* BQ27xxx battery monitor HDQ/1-wire driver
|
|
*
|
|
* Copyright (C) 2007-2017 Texas Instruments Incorporated - http://www.ti.com/
|
|
*
|
|
* This program is free software; you can redistribute it and/or modify
|
|
* it under the terms of the GNU General Public License version 2 as
|
|
* published by the Free Software Foundation.
|
|
*
|
|
* This program is distributed "as is" WITHOUT ANY WARRANTY of any
|
|
* kind, whether express or implied; without even the implied warranty
|
|
* of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
|
|
* GNU General Public License for more details.
|
|
*/
|
|
|
|
#include <linux/kernel.h>
|
|
#include <linux/module.h>
|
|
#include <linux/device.h>
|
|
#include <linux/types.h>
|
|
#include <linux/platform_device.h>
|
|
#include <linux/mutex.h>
|
|
#include <linux/power/bq27xxx_battery.h>
|
|
|
|
#include <linux/w1.h>
|
|
|
|
#define W1_FAMILY_BQ27000 0x01
|
|
|
|
#define HDQ_CMD_READ (0 << 7)
|
|
#define HDQ_CMD_WRITE (1 << 7)
|
|
|
|
static int F_ID;
|
|
module_param(F_ID, int, S_IRUSR);
|
|
MODULE_PARM_DESC(F_ID, "1-wire slave FID for BQ27xxx device");
|
|
|
|
static int w1_bq27000_read(struct w1_slave *sl, unsigned int reg)
|
|
{
|
|
u8 val;
|
|
|
|
mutex_lock(&sl->master->bus_mutex);
|
|
w1_write_8(sl->master, HDQ_CMD_READ | reg);
|
|
val = w1_read_8(sl->master);
|
|
mutex_unlock(&sl->master->bus_mutex);
|
|
|
|
return val;
|
|
}
|
|
|
|
static int bq27xxx_battery_hdq_read(struct bq27xxx_device_info *di, u8 reg,
|
|
bool single)
|
|
{
|
|
struct w1_slave *sl = dev_to_w1_slave(di->dev);
|
|
unsigned int timeout = 3;
|
|
int upper, lower;
|
|
int temp;
|
|
|
|
if (!single) {
|
|
/*
|
|
* Make sure the value has not changed in between reading the
|
|
* lower and the upper part
|
|
*/
|
|
upper = w1_bq27000_read(sl, reg + 1);
|
|
do {
|
|
temp = upper;
|
|
if (upper < 0)
|
|
return upper;
|
|
|
|
lower = w1_bq27000_read(sl, reg);
|
|
if (lower < 0)
|
|
return lower;
|
|
|
|
upper = w1_bq27000_read(sl, reg + 1);
|
|
} while (temp != upper && --timeout);
|
|
|
|
if (timeout == 0)
|
|
return -EIO;
|
|
|
|
return (upper << 8) | lower;
|
|
}
|
|
|
|
return w1_bq27000_read(sl, reg);
|
|
}
|
|
|
|
static int bq27xxx_battery_hdq_add_slave(struct w1_slave *sl)
|
|
{
|
|
struct bq27xxx_device_info *di;
|
|
|
|
di = devm_kzalloc(&sl->dev, sizeof(*di), GFP_KERNEL);
|
|
if (!di)
|
|
return -ENOMEM;
|
|
|
|
dev_set_drvdata(&sl->dev, di);
|
|
|
|
di->dev = &sl->dev;
|
|
di->chip = BQ27000;
|
|
di->name = "bq27000-battery";
|
|
di->bus.read = bq27xxx_battery_hdq_read;
|
|
|
|
return bq27xxx_battery_setup(di);
|
|
}
|
|
|
|
static void bq27xxx_battery_hdq_remove_slave(struct w1_slave *sl)
|
|
{
|
|
struct bq27xxx_device_info *di = dev_get_drvdata(&sl->dev);
|
|
|
|
bq27xxx_battery_teardown(di);
|
|
}
|
|
|
|
static struct w1_family_ops bq27xxx_battery_hdq_fops = {
|
|
.add_slave = bq27xxx_battery_hdq_add_slave,
|
|
.remove_slave = bq27xxx_battery_hdq_remove_slave,
|
|
};
|
|
|
|
static struct w1_family bq27xxx_battery_hdq_family = {
|
|
.fid = W1_FAMILY_BQ27000,
|
|
.fops = &bq27xxx_battery_hdq_fops,
|
|
};
|
|
|
|
static int __init bq27xxx_battery_hdq_init(void)
|
|
{
|
|
if (F_ID)
|
|
bq27xxx_battery_hdq_family.fid = F_ID;
|
|
|
|
return w1_register_family(&bq27xxx_battery_hdq_family);
|
|
}
|
|
module_init(bq27xxx_battery_hdq_init);
|
|
|
|
static void __exit bq27xxx_battery_hdq_exit(void)
|
|
{
|
|
w1_unregister_family(&bq27xxx_battery_hdq_family);
|
|
}
|
|
module_exit(bq27xxx_battery_hdq_exit);
|
|
|
|
MODULE_AUTHOR("Texas Instruments Ltd");
|
|
MODULE_DESCRIPTION("BQ27xxx battery monitor HDQ/1-wire driver");
|
|
MODULE_LICENSE("GPL");
|
|
MODULE_ALIAS("w1-family-" __stringify(W1_FAMILY_BQ27000));
|
|
|