[PATCH 03/17] Input: sun4i-ts: Add thermal zone sensor support
Chen-Yu Tsai
wens at csie.org
Mon Jan 5 18:35:13 PST 2015
The touchscreen controller has a temperature sensor embedded in the SoC,
which already has hwmon support in the driver.
Add DT thermal zone support so we can use it with cpufreq for thermal
throttling.
Signed-off-by: Chen-Yu Tsai <wens at csie.org>
---
.../bindings/input/touchscreen/sun4i.txt | 1 +
drivers/input/touchscreen/sun4i-ts.c | 27 ++++++++++++++++++++++
2 files changed, 28 insertions(+)
diff --git a/Documentation/devicetree/bindings/input/touchscreen/sun4i.txt b/Documentation/devicetree/bindings/input/touchscreen/sun4i.txt
index aef57791f40b..7f1110adbd24 100644
--- a/Documentation/devicetree/bindings/input/touchscreen/sun4i.txt
+++ b/Documentation/devicetree/bindings/input/touchscreen/sun4i.txt
@@ -5,6 +5,7 @@ Required properties:
- compatible: "allwinner,sun4i-a10-ts"
- reg: mmio address range of the chip
- interrupts: interrupt to which the chip is connected
+ - #thermal-sensor-cells: shall be 0
Optional properties:
- allwinner,ts-attached: boolean indicating that an actual touchscreen is
diff --git a/drivers/input/touchscreen/sun4i-ts.c b/drivers/input/touchscreen/sun4i-ts.c
index 28a06749ae42..b6e9043446d6 100644
--- a/drivers/input/touchscreen/sun4i-ts.c
+++ b/drivers/input/touchscreen/sun4i-ts.c
@@ -34,6 +34,7 @@
#include <linux/err.h>
#include <linux/hwmon.h>
+#include <linux/thermal.h>
#include <linux/init.h>
#include <linux/input.h>
#include <linux/interrupt.h>
@@ -107,6 +108,7 @@
struct sun4i_ts_data {
struct device *dev;
struct input_dev *input;
+ struct thermal_zone_device *tz;
void __iomem *base;
unsigned int irq;
bool ignore_fifo_data;
@@ -180,6 +182,23 @@ static void sun4i_ts_close(struct input_dev *dev)
writel(TEMP_IRQ_EN(1), ts->base + TP_INT_FIFOC);
}
+static int get_temp(void *data, long *temp)
+{
+ struct sun4i_ts_data *ts = data;
+
+ /* No temp_data until the first irq */
+ if (ts->temp_data == -1)
+ return -EAGAIN;
+
+ *temp = (ts->temp_data - 1447) * 100;
+
+ return 0;
+}
+
+static struct thermal_zone_of_device_ops sun4i_ts_tz_ops = {
+ .get_temp = get_temp,
+};
+
static ssize_t show_temp(struct device *dev, struct device_attribute *devattr,
char *buf)
{
@@ -288,6 +307,11 @@ static int sun4i_ts_probe(struct platform_device *pdev)
if (IS_ERR(hwmon))
return PTR_ERR(hwmon);
+ ts->tz = thermal_zone_of_sensor_register(ts->dev, 0, ts,
+ &sun4i_ts_tz_ops);
+ if (IS_ERR(ts->tz))
+ ts->tz = NULL;
+
writel(TEMP_IRQ_EN(1), ts->base + TP_INT_FIFOC);
if (ts_attached) {
@@ -310,6 +334,9 @@ static int sun4i_ts_remove(struct platform_device *pdev)
if (ts->input)
input_unregister_device(ts->input);
+ if (ts->tz)
+ thermal_zone_of_sensor_unregister(ts->dev, ts->tz);
+
/* Deactivate all IRQs */
writel(0, ts->base + TP_INT_FIFOC);
--
2.1.4
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