blob: 819c6d5d7aa714914b6611fb306fd74bea48344c [file] [log] [blame] [edit]
/*
* Copyright (c) 2011-2015, The Linux Foundation. All rights reserved.
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 and
* only version 2 as published by the Free Software Foundation.
*
* 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.
*/
#include <linux/delay.h>
#include <linux/err.h>
#include <linux/iio/consumer.h>
#include <linux/interrupt.h>
#include <linux/module.h>
#include <linux/of.h>
#include <linux/of_device.h>
#include <linux/platform_device.h>
#include <linux/regmap.h>
#include <linux/thermal.h>
#define QPNP_TM_REG_TYPE 0x04
#define QPNP_TM_REG_SUBTYPE 0x05
#define QPNP_TM_REG_STATUS 0x08
#define QPNP_TM_REG_SHUTDOWN_CTRL1 0x40
#define QPNP_TM_REG_ALARM_CTRL 0x46
#define QPNP_TM_TYPE 0x09
#define QPNP_TM_SUBTYPE 0x08
#define STATUS_STAGE_MASK 0x03
#define SHUTDOWN_CTRL1_THRESHOLD_MASK 0x03
#define ALARM_CTRL_FORCE_ENABLE 0x80
/*
* Trip point values based on threshold control
* 0 = {105 C, 125 C, 145 C}
* 1 = {110 C, 130 C, 150 C}
* 2 = {115 C, 135 C, 155 C}
* 3 = {120 C, 140 C, 160 C}
*/
#define TEMP_STAGE_STEP 20000 /* Stage step: 20.000 C */
#define TEMP_STAGE_HYSTERESIS 2000
#define TEMP_THRESH_MIN 105000 /* Threshold Min: 105 C */
#define TEMP_THRESH_STEP 5000 /* Threshold step: 5 C */
#define THRESH_MIN 0
/* Temperature in Milli Celsius reported during stage 0 if no ADC is present */
#define DEFAULT_TEMP 37000
struct qpnp_tm_chip {
struct regmap *map;
struct thermal_zone_device *tz_dev;
long temp;
unsigned int thresh;
unsigned int stage;
unsigned int prev_stage;
unsigned int base;
struct iio_channel *adc;
};
static int qpnp_tm_read(struct qpnp_tm_chip *chip, u16 addr, u8 *data)
{
unsigned int val;
int ret;
ret = regmap_read(chip->map, chip->base + addr, &val);
if (ret < 0)
return ret;
*data = val;
return 0;
}
static int qpnp_tm_write(struct qpnp_tm_chip *chip, u16 addr, u8 data)
{
return regmap_write(chip->map, chip->base + addr, data);
}
/*
* This function updates the internal temp value based on the
* current thermal stage and threshold as well as the previous stage
*/
static int qpnp_tm_update_temp_no_adc(struct qpnp_tm_chip *chip)
{
unsigned int stage;
int ret;
u8 reg = 0;
ret = qpnp_tm_read(chip, QPNP_TM_REG_STATUS, &reg);
if (ret < 0)
return ret;
stage = reg & STATUS_STAGE_MASK;
if (stage > chip->stage) {
/* increasing stage, use lower bound */
chip->temp = (stage - 1) * TEMP_STAGE_STEP +
chip->thresh * TEMP_THRESH_STEP +
TEMP_STAGE_HYSTERESIS + TEMP_THRESH_MIN;
} else if (stage < chip->stage) {
/* decreasing stage, use upper bound */
chip->temp = stage * TEMP_STAGE_STEP +
chip->thresh * TEMP_THRESH_STEP -
TEMP_STAGE_HYSTERESIS + TEMP_THRESH_MIN;
}
chip->stage = stage;
return 0;
}
static int qpnp_tm_get_temp(void *data, int *temp)
{
struct qpnp_tm_chip *chip = data;
int ret, mili_celsius;
if (!temp)
return -EINVAL;
if (IS_ERR(chip->adc)) {
ret = qpnp_tm_update_temp_no_adc(chip);
if (ret < 0)
return ret;
} else {
ret = iio_read_channel_processed(chip->adc, &mili_celsius);
if (ret < 0)
return ret;
chip->temp = mili_celsius;
}
*temp = chip->temp < 0 ? 0 : chip->temp;
return 0;
}
static const struct thermal_zone_of_device_ops qpnp_tm_sensor_ops = {
.get_temp = qpnp_tm_get_temp,
};
static irqreturn_t qpnp_tm_isr(int irq, void *data)
{
struct qpnp_tm_chip *chip = data;
thermal_zone_device_update(chip->tz_dev, THERMAL_EVENT_UNSPECIFIED);
return IRQ_HANDLED;
}
/*
* This function initializes the internal temp value based on only the
* current thermal stage and threshold. Setup threshold control and
* disable shutdown override.
*/
static int qpnp_tm_init(struct qpnp_tm_chip *chip)
{
int ret;
u8 reg;
chip->thresh = THRESH_MIN;
chip->temp = DEFAULT_TEMP;
ret = qpnp_tm_read(chip, QPNP_TM_REG_STATUS, &reg);
if (ret < 0)
return ret;
chip->stage = reg & STATUS_STAGE_MASK;
if (chip->stage)
chip->temp = chip->thresh * TEMP_THRESH_STEP +
(chip->stage - 1) * TEMP_STAGE_STEP +
TEMP_THRESH_MIN;
/*
* Set threshold and disable software override of stage 2 and 3
* shutdowns.
*/
reg = chip->thresh & SHUTDOWN_CTRL1_THRESHOLD_MASK;
ret = qpnp_tm_write(chip, QPNP_TM_REG_SHUTDOWN_CTRL1, reg);
if (ret < 0)
return ret;
/* Enable the thermal alarm PMIC module in always-on mode. */
reg = ALARM_CTRL_FORCE_ENABLE;
ret = qpnp_tm_write(chip, QPNP_TM_REG_ALARM_CTRL, reg);
return ret;
}
static int qpnp_tm_probe(struct platform_device *pdev)
{
struct qpnp_tm_chip *chip;
struct device_node *node;
u8 type, subtype;
u32 res[2];
int ret, irq;
node = pdev->dev.of_node;
chip = devm_kzalloc(&pdev->dev, sizeof(*chip), GFP_KERNEL);
if (!chip)
return -ENOMEM;
dev_set_drvdata(&pdev->dev, chip);
chip->map = dev_get_regmap(pdev->dev.parent, NULL);
if (!chip->map)
return -ENXIO;
ret = of_property_read_u32_array(node, "reg", res, 2);
if (ret < 0)
return ret;
irq = platform_get_irq(pdev, 0);
if (irq < 0)
return irq;
/* ADC based measurements are optional */
chip->adc = iio_channel_get(&pdev->dev, "thermal");
if (PTR_ERR(chip->adc) == -EPROBE_DEFER)
return PTR_ERR(chip->adc);
chip->base = res[0];
ret = qpnp_tm_read(chip, QPNP_TM_REG_TYPE, &type);
if (ret < 0) {
dev_err(&pdev->dev, "could not read type\n");
goto fail;
}
ret = qpnp_tm_read(chip, QPNP_TM_REG_SUBTYPE, &subtype);
if (ret < 0) {
dev_err(&pdev->dev, "could not read subtype\n");
goto fail;
}
if (type != QPNP_TM_TYPE || subtype != QPNP_TM_SUBTYPE) {
dev_err(&pdev->dev, "invalid type 0x%02x or subtype 0x%02x\n",
type, subtype);
ret = -ENODEV;
goto fail;
}
ret = qpnp_tm_init(chip);
if (ret < 0) {
dev_err(&pdev->dev, "init failed\n");
goto fail;
}
ret = devm_request_threaded_irq(&pdev->dev, irq, NULL, qpnp_tm_isr,
IRQF_ONESHOT, node->name, chip);
if (ret < 0)
goto fail;
chip->tz_dev = devm_thermal_zone_of_sensor_register(&pdev->dev, 0, chip,
&qpnp_tm_sensor_ops);
if (IS_ERR(chip->tz_dev)) {
dev_err(&pdev->dev, "failed to register sensor\n");
ret = PTR_ERR(chip->tz_dev);
goto fail;
}
return 0;
fail:
if (!IS_ERR(chip->adc))
iio_channel_release(chip->adc);
return ret;
}
static int qpnp_tm_remove(struct platform_device *pdev)
{
struct qpnp_tm_chip *chip = dev_get_drvdata(&pdev->dev);
if (!IS_ERR(chip->adc))
iio_channel_release(chip->adc);
return 0;
}
static const struct of_device_id qpnp_tm_match_table[] = {
{ .compatible = "qcom,spmi-temp-alarm" },
{ }
};
MODULE_DEVICE_TABLE(of, qpnp_tm_match_table);
static struct platform_driver qpnp_tm_driver = {
.driver = {
.name = "spmi-temp-alarm",
.of_match_table = qpnp_tm_match_table,
},
.probe = qpnp_tm_probe,
.remove = qpnp_tm_remove,
};
module_platform_driver(qpnp_tm_driver);
MODULE_ALIAS("platform:spmi-temp-alarm");
MODULE_DESCRIPTION("QPNP PMIC Temperature Alarm driver");
MODULE_LICENSE("GPL v2");