/*
* tps65910.c -- TI TPS6591x
*
* Copyright 2010 Texas Instruments Inc.
*
* Author: Jorge Eduardo Candelaria <jedu@slimlogic.co.uk>
*
* 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.
*
*/
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/init.h>
#include <linux/slab.h>
#include <linux/err.h>
#include <linux/platform_device.h>
#include <linux/debugfs.h>
#include <linux/gpio.h>
#include <linux/mfd/tps65910.h>
#define COMP 0
#define COMP1 1
#define COMP2 2
/* Comparator 1 voltage selection table in millivolts */
static const u16 COMP_VSEL_TABLE[] = {
0, 2500, 2500, 2500, 2500, 2550, 2600, 2650,
2700, 2750, 2800, 2850, 2900, 2950, 3000, 3050,
3100, 3150, 3200, 3250, 3300, 3350, 3400, 3450,
3500,
};
struct comparator {
const char *name;
int reg;
int uV_max;
const u16 *vsel_table;
};
static struct comparator tps_comparators[] = {
{
.name = "COMP1",
.reg = TPS65911_VMBCH,
.uV_max = 3500,
.vsel_table = COMP_VSEL_TABLE,
},
{
.name = "COMP2",
.reg = TPS65911_VMBCH2,
.uV_max = 3500,
.vsel_table = COMP_VSEL_TABLE,
},
};
static int comp_threshold_set(struct tps65910 *tps65910, int id, int voltage)
{
struct comparator tps_comp = tps_comparators[id];
int curr_voltage = 0;
int ret;
u8 index = 0, val;
if (id == COMP)
return 0;
while (curr_voltage < tps_comp.uV_max) {
curr_voltage = tps_comp.vsel_table[index];
if (curr_voltage >= voltage)
break;
else if (curr_voltage < voltage)
index ++;
}
if (curr_voltage > tps_comp.uV_max)
return -EINVAL;
val = index << 1;
ret = tps65910->write(tps65910, tps_comp.reg, 1, &val);
return ret;
}
static int comp_threshold_get(struct tps65910 *tps65910, int id)
{
struct comparator tps_comp = tps_comparators[id];
int ret;
u8 val;
if (id == COMP)
return 0;
ret = tps65910->read(tps65910, tps_comp.reg, 1, &val);
if (ret < 0)
return ret;
val >>= 1;
return tps_comp.vsel_table[val];
}
static ssize_t comp_threshold_show(struct device *dev,
struct device_attribute *attr, char *buf)
{
struct tps65910 *tps65910 = dev_get_drvdata(dev->parent);
struct attribute comp_attr = attr->attr;
int id, uVolt;
if (!strcmp(comp_attr.name, "comp1_threshold"))
id = COMP1;
else if (!strcmp(comp_attr.name, "comp2_threshold"))
id = COMP2;
else
return -EINVAL;
uVolt = comp_threshold_get(tps65910, id);
return sprintf(buf, "%d\n", uVolt);
}
static DEVICE_ATTR(comp1_threshold, S_IRUGO, comp_threshold_show, NULL);
static DEVICE_ATTR(comp2_threshold, S_IRUGO, comp_threshold_show, NULL);
static __devinit int tps65911_comparator_probe(struct platform_device *pdev)
{
struct tps65910 *tps65910 = dev_get_drvdata(pdev->dev.parent);
struct tps65910_board *pdata = dev_get_platdata(tps65910->dev);
int ret;
ret = comp_threshold_set(tps65910, COMP1, pdata->vmbch_threshold);
if (ret < 0) {
dev_err(&pdev->dev, "cannot set COMP1 threshold\n");
return ret;
}
ret = comp_threshold_set(tps65910, COMP2, pdata->vmbch2_threshold);
if (ret < 0) {
dev_err(&pdev->dev, "cannot set COMP2 theshold\n");
return ret;
}
/* Create sysfs entry */
ret = device_create_file(&pdev->dev, &dev_attr_comp1_threshold);
if (ret < 0)
dev_err(&pdev->dev, "failed to add COMP1 sysfs file\n");
ret = device_create_file(&pdev->dev, &dev_attr_comp2_threshold);
if (ret < 0)
dev_err(&pdev->dev, "failed to add COMP2 sysfs file\n");
return ret;
}
static __devexit int tps65911_comparator_remove(struct platform_device *pdev)
{
struct tps65910 *tps65910;
tps65910 = dev_get_drvdata(pdev->dev.parent);
device_remove_file(&pdev->dev, &dev_attr_comp2_threshold);
device_remove_file(&pdev->dev, &dev_attr_comp1_threshold);
return 0;
}
static struct platform_driver tps65911_comparator_driver = {
.driver = {
.name = "tps65911-comparator",
.owner = THIS_MODULE,
},
.probe = tps65911_comparator_probe,
.remove = __devexit_p(tps65911_comparator_remove),
};
static int __init tps65911_comparator_init(void)
{
return platform_driver_register(&tps65911_comparator_driver);
}
subsys_initcall(tps65911_comparator_init);
static void __exit tps65911_comparator_exit(void)
{
platform_driver_unregister(&tps65911_comparator_driver);
}
module_exit(tps65911_comparator_exit);
MODULE_AUTHOR("Jorge Eduardo Candelaria <jedu@slimlogic.co.uk>");
MODULE_DESCRIPTION("TPS65911 comparator driver");
MODULE_LICENSE("GPL v2");
MODULE_ALIAS("platform:tps65911-comparator");
