blob: 12cc0728de22f4d7fff4452eb3598f3e2f35b0ca [file] [log] [blame]
/*
* Broadcom STB AVS TMON thermal sensor driver
*
* Copyright (C) 2015 Broadcom Corporation
*
* This software is licensed under the terms of the GNU General Public
* License version 2, as published by the Free Software Foundation, and
* may be copied, distributed, and modified under those terms.
*
* 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.
*
*/
#define DRV_NAME "brcmstb_thermal"
#define pr_fmt(fmt) DRV_NAME ": " fmt
#include <linux/bitops.h>
#include <linux/device.h>
#include <linux/err.h>
#include <linux/io.h>
#include <linux/irqreturn.h>
#include <linux/interrupt.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/platform_device.h>
#include <linux/of_device.h>
#include <linux/thermal.h>
#define AVS_TMON_STATUS 0x00
#define AVS_TMON_STATUS_valid_msk BIT(11)
#define AVS_TMON_STATUS_data_msk GENMASK(10, 1)
#define AVS_TMON_STATUS_data_shift 1
#define AVS_TMON_EN_OVERTEMP_RESET 0x04
#define AVS_TMON_EN_OVERTEMP_RESET_msk BIT(0)
#define AVS_TMON_RESET_THRESH 0x08
#define AVS_TMON_RESET_THRESH_msk GENMASK(10, 1)
#define AVS_TMON_RESET_THRESH_shift 1
#define AVS_TMON_INT_IDLE_TIME 0x10
#define AVS_TMON_EN_TEMP_INT_SRCS 0x14
#define AVS_TMON_EN_TEMP_INT_SRCS_high BIT(1)
#define AVS_TMON_EN_TEMP_INT_SRCS_low BIT(0)
#define AVS_TMON_INT_THRESH 0x18
#define AVS_TMON_INT_THRESH_high_msk GENMASK(26, 17)
#define AVS_TMON_INT_THRESH_high_shift 17
#define AVS_TMON_INT_THRESH_low_msk GENMASK(10, 1)
#define AVS_TMON_INT_THRESH_low_shift 1
#define AVS_TMON_TEMP_INT_CODE 0x1c
#define AVS_TMON_TP_TEST_ENABLE 0x20
enum avs_tmon_trip_type {
TMON_TRIP_TYPE_LOW = 0,
TMON_TRIP_TYPE_HIGH,
TMON_TRIP_TYPE_RESET,
TMON_TRIP_TYPE_MAX,
};
struct avs_tmon_trip {
/* HW bit to enable the trip */
u32 enable_offs;
u32 enable_mask;
/* HW field to read the trip temperature */
u32 reg_offs;
u32 reg_msk;
int reg_shift;
};
static struct avs_tmon_trip avs_tmon_trips[] = {
/* Trips when temperature is below threshold */
[TMON_TRIP_TYPE_LOW] = {
.enable_offs = AVS_TMON_EN_TEMP_INT_SRCS,
.enable_mask = AVS_TMON_EN_TEMP_INT_SRCS_low,
.reg_offs = AVS_TMON_INT_THRESH,
.reg_msk = AVS_TMON_INT_THRESH_low_msk,
.reg_shift = AVS_TMON_INT_THRESH_low_shift,
},
/* Trips when temperature is above threshold */
[TMON_TRIP_TYPE_HIGH] = {
.enable_offs = AVS_TMON_EN_TEMP_INT_SRCS,
.enable_mask = AVS_TMON_EN_TEMP_INT_SRCS_high,
.reg_offs = AVS_TMON_INT_THRESH,
.reg_msk = AVS_TMON_INT_THRESH_high_msk,
.reg_shift = AVS_TMON_INT_THRESH_high_shift,
},
/* Automatically resets chip when above threshold */
[TMON_TRIP_TYPE_RESET] = {
.enable_offs = AVS_TMON_EN_OVERTEMP_RESET,
.enable_mask = AVS_TMON_EN_OVERTEMP_RESET_msk,
.reg_offs = AVS_TMON_RESET_THRESH,
.reg_msk = AVS_TMON_RESET_THRESH_msk,
.reg_shift = AVS_TMON_RESET_THRESH_shift,
},
};
enum {
/*
* Using the of-thermal framework
*/
AVS_TMON_OF_SENSOR_DRIVER,
/*
* Old DT bindings didn't include the of-sensor framework, so support a
* full zone implementation temporarily
*/
AVS_TMON_ZONE_DRIVER,
};
struct brcmstb_thermal_priv {
void __iomem *tmon_base;
struct device *dev;
struct thermal_zone_device *thermal;
/*
* When .thermal is non-zero this member indicates whether
* this driver registered as a sensor (AVS_TMON_OF_SENSOR_DRIVER)
* or as a zone (AVS_TMON_ZONE_DRIVER)
*/
int regtype;
};
/* Convert a HW code to a temperature reading (millidegree celsius) */
static inline int avs_tmon_code_to_temp(u32 code)
{
return (410040 - (int)((code & 0x3FF) * 487));
}
/*
* Convert a temperature value (millidegree celsius) to a HW code
*
* @temp: temperature to convert
* @low: if true, round toward the low side
*/
static inline u32 avs_tmon_temp_to_code(int temp, bool low)
{
if (temp < -88161)
return 0x3FF; /* Maximum code value */
if (temp >= 410040)
return 0; /* Minimum code value */
if (low)
return (u32)(DIV_ROUND_UP(410040 - temp, 487));
else
return (u32)((410040 - temp) / 487);
}
static int brcmstb_get_temp(void *data, long *temp)
{
struct brcmstb_thermal_priv *priv = data;
u32 val;
long t;
val = __raw_readl(priv->tmon_base + AVS_TMON_STATUS);
if (!(val & AVS_TMON_STATUS_valid_msk)) {
dev_err(priv->dev, "reading not valid\n");
return -EIO;
}
val = (val & AVS_TMON_STATUS_data_msk) >> AVS_TMON_STATUS_data_shift;
t = avs_tmon_code_to_temp(val);
if (t < 0)
*temp = 0;
else
*temp = t;
return 0;
}
/*
* Active when the of-thermal framework is not used
*/
static int brcmstb_get_zone_temp(struct thermal_zone_device *thermal,
unsigned long *temp)
{
return brcmstb_get_temp(thermal->devdata, temp);
}
static void avs_tmon_trip_enable(struct brcmstb_thermal_priv *priv,
enum avs_tmon_trip_type type, int en)
{
struct avs_tmon_trip *trip = &avs_tmon_trips[type];
u32 val = __raw_readl(priv->tmon_base + trip->enable_offs);
pr_debug("%s trip, type %d\n", en ? "enable" : "disable", type);
if (en)
val |= trip->enable_mask;
else
val &= ~trip->enable_mask;
__raw_writel(val, priv->tmon_base + trip->enable_offs);
}
static int avs_tmon_get_trip_temp(struct brcmstb_thermal_priv *priv,
enum avs_tmon_trip_type type)
{
struct avs_tmon_trip *trip = &avs_tmon_trips[type];
u32 val = __raw_readl(priv->tmon_base + trip->reg_offs);
val &= trip->reg_msk;
val >>= trip->reg_shift;
return avs_tmon_code_to_temp(val);
}
static void avs_tmon_set_trip_temp(struct brcmstb_thermal_priv *priv,
enum avs_tmon_trip_type type,
int temp)
{
struct avs_tmon_trip *trip = &avs_tmon_trips[type];
u32 val, orig;
pr_debug("set temp %d to %d\n", type, temp);
/* round toward low temp for the low interrupt */
val = avs_tmon_temp_to_code(temp, type == TMON_TRIP_TYPE_LOW);
/* TODO: Check for overflow? */
val <<= trip->reg_shift;
val &= trip->reg_msk;
orig = __raw_readl(priv->tmon_base + trip->reg_offs);
orig &= ~trip->reg_msk;
orig |= val;
__raw_writel(orig, priv->tmon_base + trip->reg_offs);
}
static int avs_tmon_get_intr_temp(struct brcmstb_thermal_priv *priv)
{
u32 val;
val = __raw_readl(priv->tmon_base + AVS_TMON_TEMP_INT_CODE);
return avs_tmon_code_to_temp(val);
}
static irqreturn_t brcmstb_tmon_irq_thread(int irq, void *data)
{
struct brcmstb_thermal_priv *priv = data;
int low, high, intr;
low = avs_tmon_get_trip_temp(priv, TMON_TRIP_TYPE_LOW);
high = avs_tmon_get_trip_temp(priv, TMON_TRIP_TYPE_HIGH);
intr = avs_tmon_get_intr_temp(priv);
dev_dbg(priv->dev, "low/intr/high: %d/%d/%d\n",
low, intr, high);
/* Disable high-temp until next threshold shift */
if (intr >= high)
avs_tmon_trip_enable(priv, TMON_TRIP_TYPE_HIGH, 0);
/* Disable low-temp until next threshold shift */
if (intr <= low)
avs_tmon_trip_enable(priv, TMON_TRIP_TYPE_LOW, 0);
/*
* Notify using the interrupt temperature, in case the temperature
* changes before it can next be read out
*/
thermal_zone_device_update_temp(priv->thermal, intr);
return IRQ_HANDLED;
}
static int brcmstb_set_trips(void *data, unsigned long low, unsigned long high)
{
struct brcmstb_thermal_priv *priv = data;
pr_debug("set trips %lu <--> %lu\n", low, high);
if (low) {
if (low > INT_MAX) {
low = INT_MAX;
}
avs_tmon_set_trip_temp(priv, TMON_TRIP_TYPE_LOW, (int)low);
avs_tmon_trip_enable(priv, TMON_TRIP_TYPE_LOW, 1);
} else {
avs_tmon_trip_enable(priv, TMON_TRIP_TYPE_LOW, 0);
}
if (high < ULONG_MAX) {
if (high > INT_MAX) {
high = INT_MAX;
}
avs_tmon_set_trip_temp(priv, TMON_TRIP_TYPE_HIGH, (int)high);
avs_tmon_trip_enable(priv, TMON_TRIP_TYPE_HIGH, 1);
} else {
avs_tmon_trip_enable(priv, TMON_TRIP_TYPE_HIGH, 0);
}
return 0;
}
static struct thermal_zone_device_ops zone_ops = {
.get_temp = brcmstb_get_zone_temp,
};
static struct thermal_zone_of_device_ops of_ops = {
.get_temp = brcmstb_get_temp,
.set_trips = brcmstb_set_trips,
};
static const struct of_device_id brcmstb_thermal_id_table[] = {
{ .compatible = "brcm,avs-tmon" },
{},
};
MODULE_DEVICE_TABLE(of, brcmstb_thermal_id_table);
/*
* Deprecated: we should be using the of-thermal framework, rather than
* registering our own thermal zone. This is provided as a temporary help, in
* case of an old device tree which does not include the thermal-zones node and
* sensor phandles.
*/
static int brcmstb_thermal_zone_probe(struct platform_device *pdev,
struct brcmstb_thermal_priv *priv)
{
struct thermal_zone_device *thermal;
thermal = thermal_zone_device_register("avs_tmon", 0, 0, priv,
&zone_ops, NULL, 0, 0);
if (IS_ERR(thermal)) {
dev_err(&pdev->dev, "failed to register zone device\n");
return PTR_ERR(thermal);
}
priv->regtype = AVS_TMON_ZONE_DRIVER;
priv->thermal = thermal;
dev_info(&pdev->dev, "registered AVS TMON zone driver\n");
return 0;
}
static int brcmstb_thermal_probe(struct platform_device *pdev)
{
struct thermal_zone_device *thermal;
struct brcmstb_thermal_priv *priv;
struct resource *res;
int irq, ret;
priv = devm_kzalloc(&pdev->dev, sizeof(*priv), GFP_KERNEL);
if (!priv)
return -ENOMEM;
res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
priv->tmon_base = devm_ioremap_resource(&pdev->dev, res);
if (IS_ERR(priv->tmon_base))
return PTR_ERR(priv->tmon_base);
priv->dev = &pdev->dev;
platform_set_drvdata(pdev, priv);
thermal = thermal_zone_of_sensor_register(&pdev->dev, 0, priv, &of_ops);
if (IS_ERR(thermal))
/*
* Fall back to registering our own zone, for legacy purposes
*/
return brcmstb_thermal_zone_probe(pdev, priv);
priv->regtype = AVS_TMON_OF_SENSOR_DRIVER;
priv->thermal = thermal;
irq = platform_get_irq(pdev, 0);
if (irq < 0) {
dev_err(&pdev->dev, "could not get IRQ\n");
ret = irq;
goto err;
}
ret = devm_request_threaded_irq(&pdev->dev, irq, NULL,
brcmstb_tmon_irq_thread, IRQF_ONESHOT,
DRV_NAME, priv);
if (ret < 0) {
dev_err(&pdev->dev, "could not request IRQ: %d\n", ret);
goto err;
}
dev_info(&pdev->dev, "registered AVS TMON of-sensor driver\n");
return 0;
err:
thermal_zone_of_sensor_unregister(&pdev->dev, priv->thermal);
return ret;
}
static int brcmstb_thermal_exit(struct platform_device *pdev)
{
struct brcmstb_thermal_priv *priv = platform_get_drvdata(pdev);
struct thermal_zone_device *thermal = priv->thermal;
if (thermal) {
if (priv->regtype == AVS_TMON_ZONE_DRIVER)
thermal_zone_device_unregister(thermal);
else
thermal_zone_of_sensor_unregister(&pdev->dev,
priv->thermal);
}
return 0;
}
static struct platform_driver brcmstb_thermal_driver = {
.probe = brcmstb_thermal_probe,
.remove = brcmstb_thermal_exit,
.driver = {
.name = DRV_NAME,
.owner = THIS_MODULE,
.of_match_table = brcmstb_thermal_id_table,
},
};
module_platform_driver(brcmstb_thermal_driver);
MODULE_LICENSE("GPL");
MODULE_AUTHOR("Brian Norris");
MODULE_DESCRIPTION("Broadcom STB AVS TMON thermal driver");