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-rw-r--r--drivers/thermal/imx_thermal.c140
1 files changed, 127 insertions, 13 deletions
diff --git a/drivers/thermal/imx_thermal.c b/drivers/thermal/imx_thermal.c
index c9a55b02..1d6c801 100644
--- a/drivers/thermal/imx_thermal.c
+++ b/drivers/thermal/imx_thermal.c
@@ -12,6 +12,7 @@
#include <linux/delay.h>
#include <linux/device.h>
#include <linux/init.h>
+#include <linux/interrupt.h>
#include <linux/io.h>
#include <linux/kernel.h>
#include <linux/mfd/syscon.h>
@@ -31,6 +32,8 @@
#define MISC0_REFTOP_SELBIASOFF (1 << 3)
#define TEMPSENSE0 0x0180
+#define TEMPSENSE0_ALARM_VALUE_SHIFT 20
+#define TEMPSENSE0_ALARM_VALUE_MASK (0xfff << TEMPSENSE0_ALARM_VALUE_SHIFT)
#define TEMPSENSE0_TEMP_CNT_SHIFT 8
#define TEMPSENSE0_TEMP_CNT_MASK (0xfff << TEMPSENSE0_TEMP_CNT_SHIFT)
#define TEMPSENSE0_FINISHED (1 << 2)
@@ -66,33 +69,62 @@ struct imx_thermal_data {
int c1, c2; /* See formula in imx_get_sensor_data() */
unsigned long temp_passive;
unsigned long temp_critical;
+ unsigned long alarm_temp;
+ unsigned long last_temp;
+ bool irq_enabled;
+ int irq;
};
+static void imx_set_alarm_temp(struct imx_thermal_data *data,
+ signed long alarm_temp)
+{
+ struct regmap *map = data->tempmon;
+ int alarm_value;
+
+ data->alarm_temp = alarm_temp;
+ alarm_value = (alarm_temp - data->c2) / data->c1;
+ regmap_write(map, TEMPSENSE0 + REG_CLR, TEMPSENSE0_ALARM_VALUE_MASK);
+ regmap_write(map, TEMPSENSE0 + REG_SET, alarm_value <<
+ TEMPSENSE0_ALARM_VALUE_SHIFT);
+}
+
static int imx_get_temp(struct thermal_zone_device *tz, unsigned long *temp)
{
struct imx_thermal_data *data = tz->devdata;
struct regmap *map = data->tempmon;
- static unsigned long last_temp;
unsigned int n_meas;
+ bool wait;
u32 val;
- /*
- * Every time we measure the temperature, we will power on the
- * temperature sensor, enable measurements, take a reading,
- * disable measurements, power off the temperature sensor.
- */
- regmap_write(map, TEMPSENSE0 + REG_CLR, TEMPSENSE0_POWER_DOWN);
- regmap_write(map, TEMPSENSE0 + REG_SET, TEMPSENSE0_MEASURE_TEMP);
+ if (data->mode == THERMAL_DEVICE_ENABLED) {
+ /* Check if a measurement is currently in progress */
+ regmap_read(map, TEMPSENSE0, &val);
+ wait = !(val & TEMPSENSE0_FINISHED);
+ } else {
+ /*
+ * Every time we measure the temperature, we will power on the
+ * temperature sensor, enable measurements, take a reading,
+ * disable measurements, power off the temperature sensor.
+ */
+ regmap_write(map, TEMPSENSE0 + REG_CLR, TEMPSENSE0_POWER_DOWN);
+ regmap_write(map, TEMPSENSE0 + REG_SET, TEMPSENSE0_MEASURE_TEMP);
+
+ wait = true;
+ }
/*
* According to the temp sensor designers, it may require up to ~17us
* to complete a measurement.
*/
- usleep_range(20, 50);
+ if (wait)
+ usleep_range(20, 50);
regmap_read(map, TEMPSENSE0, &val);
- regmap_write(map, TEMPSENSE0 + REG_CLR, TEMPSENSE0_MEASURE_TEMP);
- regmap_write(map, TEMPSENSE0 + REG_SET, TEMPSENSE0_POWER_DOWN);
+
+ if (data->mode != THERMAL_DEVICE_ENABLED) {
+ regmap_write(map, TEMPSENSE0 + REG_CLR, TEMPSENSE0_MEASURE_TEMP);
+ regmap_write(map, TEMPSENSE0 + REG_SET, TEMPSENSE0_POWER_DOWN);
+ }
if ((val & TEMPSENSE0_FINISHED) == 0) {
dev_dbg(&tz->device, "temp measurement never finished\n");
@@ -104,9 +136,24 @@ static int imx_get_temp(struct thermal_zone_device *tz, unsigned long *temp)
/* See imx_get_sensor_data() for formula derivation */
*temp = data->c2 + data->c1 * n_meas;
- if (*temp != last_temp) {
+ /* Update alarm value to next higher trip point */
+ if (data->alarm_temp == data->temp_passive && *temp >= data->temp_passive)
+ imx_set_alarm_temp(data, data->temp_critical);
+ if (data->alarm_temp == data->temp_critical && *temp < data->temp_passive) {
+ imx_set_alarm_temp(data, data->temp_passive);
+ dev_dbg(&tz->device, "thermal alarm off: T < %lu\n",
+ data->alarm_temp / 1000);
+ }
+
+ if (*temp != data->last_temp) {
dev_dbg(&tz->device, "millicelsius: %ld\n", *temp);
- last_temp = *temp;
+ data->last_temp = *temp;
+ }
+
+ /* Reenable alarm IRQ if temperature below alarm temperature */
+ if (!data->irq_enabled && *temp < data->alarm_temp) {
+ data->irq_enabled = true;
+ enable_irq(data->irq);
}
return 0;
@@ -126,13 +173,30 @@ static int imx_set_mode(struct thermal_zone_device *tz,
enum thermal_device_mode mode)
{
struct imx_thermal_data *data = tz->devdata;
+ struct regmap *map = data->tempmon;
if (mode == THERMAL_DEVICE_ENABLED) {
tz->polling_delay = IMX_POLLING_DELAY;
tz->passive_delay = IMX_PASSIVE_DELAY;
+
+ regmap_write(map, TEMPSENSE0 + REG_CLR, TEMPSENSE0_POWER_DOWN);
+ regmap_write(map, TEMPSENSE0 + REG_SET, TEMPSENSE0_MEASURE_TEMP);
+
+ if (!data->irq_enabled) {
+ data->irq_enabled = true;
+ enable_irq(data->irq);
+ }
} else {
+ regmap_write(map, TEMPSENSE0 + REG_CLR, TEMPSENSE0_MEASURE_TEMP);
+ regmap_write(map, TEMPSENSE0 + REG_SET, TEMPSENSE0_POWER_DOWN);
+
tz->polling_delay = 0;
tz->passive_delay = 0;
+
+ if (data->irq_enabled) {
+ disable_irq(data->irq);
+ data->irq_enabled = false;
+ }
}
data->mode = mode;
@@ -181,6 +245,8 @@ static int imx_set_trip_temp(struct thermal_zone_device *tz, int trip,
data->temp_passive = temp;
+ imx_set_alarm_temp(data, temp);
+
return 0;
}
@@ -299,11 +365,34 @@ static int imx_get_sensor_data(struct platform_device *pdev)
return 0;
}
+static irqreturn_t imx_thermal_alarm_irq(int irq, void *dev)
+{
+ struct imx_thermal_data *data = dev;
+
+ disable_irq_nosync(irq);
+ data->irq_enabled = false;
+
+ return IRQ_WAKE_THREAD;
+}
+
+static irqreturn_t imx_thermal_alarm_irq_thread(int irq, void *dev)
+{
+ struct imx_thermal_data *data = dev;
+
+ dev_dbg(&data->tz->device, "THERMAL ALARM: T > %lu\n",
+ data->alarm_temp / 1000);
+
+ thermal_zone_device_update(data->tz);
+
+ return IRQ_HANDLED;
+}
+
static int imx_thermal_probe(struct platform_device *pdev)
{
struct imx_thermal_data *data;
struct cpumask clip_cpus;
struct regmap *map;
+ int measure_freq;
int ret;
data = devm_kzalloc(&pdev->dev, sizeof(*data), GFP_KERNEL);
@@ -318,6 +407,18 @@ static int imx_thermal_probe(struct platform_device *pdev)
}
data->tempmon = map;
+ data->irq = platform_get_irq(pdev, 0);
+ if (data->irq < 0)
+ return data->irq;
+
+ ret = devm_request_threaded_irq(&pdev->dev, data->irq,
+ imx_thermal_alarm_irq, imx_thermal_alarm_irq_thread,
+ 0, "imx_thermal", data);
+ if (ret < 0) {
+ dev_err(&pdev->dev, "failed to request alarm irq: %d\n", ret);
+ return ret;
+ }
+
platform_set_drvdata(pdev, data);
ret = imx_get_sensor_data(pdev);
@@ -356,6 +457,15 @@ static int imx_thermal_probe(struct platform_device *pdev)
return ret;
}
+ /* Enable measurements at ~ 10 Hz */
+ regmap_write(map, TEMPSENSE1 + REG_CLR, TEMPSENSE1_MEASURE_FREQ);
+ measure_freq = DIV_ROUND_UP(32768, 10); /* 10 Hz */
+ regmap_write(map, TEMPSENSE1 + REG_SET, measure_freq);
+ imx_set_alarm_temp(data, data->temp_passive);
+ regmap_write(map, TEMPSENSE0 + REG_CLR, TEMPSENSE0_POWER_DOWN);
+ regmap_write(map, TEMPSENSE0 + REG_SET, TEMPSENSE0_MEASURE_TEMP);
+
+ data->irq_enabled = true;
data->mode = THERMAL_DEVICE_ENABLED;
return 0;
@@ -364,6 +474,10 @@ static int imx_thermal_probe(struct platform_device *pdev)
static int imx_thermal_remove(struct platform_device *pdev)
{
struct imx_thermal_data *data = platform_get_drvdata(pdev);
+ struct regmap *map = data->tempmon;
+
+ /* Disable measurements */
+ regmap_write(map, TEMPSENSE0 + REG_SET, TEMPSENSE0_POWER_DOWN);
thermal_zone_device_unregister(data->tz);
cpufreq_cooling_unregister(data->cdev);
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