blob: 5ab0ecfdc022e59847bbb1c0d07029335826d711 [file] [log] [blame]
/* Copyright (c) 2015, 2017 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/bitops.h>
#include <linux/kernel.h>
#include <linux/errno.h>
#include <linux/delay.h>
#include <linux/thermal.h>
#include <sound/soc.h>
#include "wsa881x-temp-sensor.h"
#define T1_TEMP -10
#define T2_TEMP 150
#define LOW_TEMP_THRESHOLD 5
#define HIGH_TEMP_THRESHOLD 45
#define TEMP_INVALID 0xFFFF
#define WSA881X_TEMP_RETRY 3
/*
* wsa881x_get_temp - get wsa temperature
* @thermal: thermal zone device
* @temp: temperature value
*
* Get the temperature of wsa881x.
*
* Return: 0 on success or negative error code on failure.
*/
int wsa881x_get_temp(struct thermal_zone_device *thermal,
int *temp)
{
struct wsa881x_tz_priv *pdata;
struct snd_soc_codec *codec;
struct wsa_temp_register reg;
int dmeas, d1, d2;
int ret = 0;
int temp_val;
int t1 = T1_TEMP;
int t2 = T2_TEMP;
u8 retry = WSA881X_TEMP_RETRY;
if (!thermal)
return -EINVAL;
if (thermal->devdata) {
pdata = thermal->devdata;
if (pdata->codec) {
codec = pdata->codec;
} else {
pr_err("%s: codec is NULL\n", __func__);
return -EINVAL;
}
} else {
pr_err("%s: pdata is NULL\n", __func__);
return -EINVAL;
}
temp_retry:
if (pdata->wsa_temp_reg_read) {
ret = pdata->wsa_temp_reg_read(codec, &reg);
if (ret) {
pr_err("%s: temperature register read failed: %d\n",
__func__, ret);
return ret;
}
} else {
pr_err("%s: wsa_temp_reg_read is NULL\n", __func__);
return -EINVAL;
}
/*
* Temperature register values are expected to be in the
* following range.
* d1_msb = 68 - 92 and d1_lsb = 0, 64, 128, 192
* d2_msb = 185 -218 and d2_lsb = 0, 64, 128, 192
*/
if ((reg.d1_msb < 68 || reg.d1_msb > 92) ||
(!(reg.d1_lsb == 0 || reg.d1_lsb == 64 || reg.d1_lsb == 128 ||
reg.d1_lsb == 192)) ||
(reg.d2_msb < 185 || reg.d2_msb > 218) ||
(!(reg.d2_lsb == 0 || reg.d2_lsb == 64 || reg.d2_lsb == 128 ||
reg.d2_lsb == 192))) {
printk_ratelimited("%s: Temperature registers[%d %d %d %d] are out of range\n",
__func__, reg.d1_msb, reg.d1_lsb, reg.d2_msb,
reg.d2_lsb);
}
dmeas = ((reg.dmeas_msb << 0x8) | reg.dmeas_lsb) >> 0x6;
d1 = ((reg.d1_msb << 0x8) | reg.d1_lsb) >> 0x6;
d2 = ((reg.d2_msb << 0x8) | reg.d2_lsb) >> 0x6;
if (d1 == d2)
temp_val = TEMP_INVALID;
else
temp_val = t1 + (((dmeas - d1) * (t2 - t1))/(d2 - d1));
if (temp_val <= LOW_TEMP_THRESHOLD ||
temp_val >= HIGH_TEMP_THRESHOLD) {
printk_ratelimited("%s: T0: %d is out of range[%d, %d]\n",
__func__, temp_val, LOW_TEMP_THRESHOLD,
HIGH_TEMP_THRESHOLD);
if (retry--) {
msleep(20);
goto temp_retry;
}
}
if (temp)
*temp = temp_val;
pr_debug("%s: t0 measured: %d dmeas = %d, d1 = %d, d2 = %d\n",
__func__, temp_val, dmeas, d1, d2);
return ret;
}
EXPORT_SYMBOL(wsa881x_get_temp);
static struct thermal_zone_device_ops wsa881x_thermal_ops = {
.get_temp = wsa881x_get_temp,
};
int wsa881x_init_thermal(struct wsa881x_tz_priv *tz_pdata)
{
struct thermal_zone_device *tz_dev;
if (tz_pdata == NULL) {
pr_err("%s: thermal pdata is NULL\n", __func__);
return -EINVAL;
}
/* Register with the thermal zone */
tz_dev = thermal_zone_device_register(tz_pdata->name,
0, 0, tz_pdata,
&wsa881x_thermal_ops, NULL, 0, 0);
if (IS_ERR(tz_dev)) {
pr_err("%s: thermal device register failed.\n", __func__);
return -EINVAL;
}
tz_pdata->tz_dev = tz_dev;
return 0;
}
EXPORT_SYMBOL(wsa881x_init_thermal);
void wsa881x_deinit_thermal(struct thermal_zone_device *tz_dev)
{
if (tz_dev)
thermal_zone_device_unregister(tz_dev);
}
EXPORT_SYMBOL(wsa881x_deinit_thermal);