[RFC PATCH 6/9] hwmon: (lm90) Register to the thermal framework

[Wei Ni <wni-DDmLM1+adcrQT0dZR+AlfA@public.gmane.org>]

Register the remote sensor to the thermal framework.
It can support to show the temperature and read/write threshold.

Signed-off-by: Wei Ni <wni-DDmLM1+adcrQT0dZR+AlfA@public.gmane.org>
---
 arch/arm/boot/dts/tegra30-cardhu.dtsi |    1 +
 drivers/hwmon/lm90.c                  |  182 ++++++++++++++++++++++++++++++++-
 2 files changed, 182 insertions(+), 1 deletion(-)

diff --git a/arch/arm/boot/dts/tegra30-cardhu.dtsi b/arch/arm/boot/dts/tegra30-cardhu.dtsi
index 15ad1ad..3f6ab89 100644
--- a/arch/arm/boot/dts/tegra30-cardhu.dtsi
+++ b/arch/arm/boot/dts/tegra30-cardhu.dtsi
@@ -279,6 +279,7 @@
 			reg = <0x4c>;
 			interrupt-parent = <&gpio>;
 			interrupts = <226 0x08>; /* gpio PCC2 */
+			#sensor-cells = <1>;
 		};
 	};
 
diff --git a/drivers/hwmon/lm90.c b/drivers/hwmon/lm90.c
index de5a476..0abdedc 100644
--- a/drivers/hwmon/lm90.c
+++ b/drivers/hwmon/lm90.c
@@ -91,6 +91,7 @@
 #include <linux/sysfs.h>
 #include <linux/interrupt.h>
 #include <linux/of_irq.h>
+#include <linux/thermal.h>
 
 /*
  * Addresses to scan
@@ -182,6 +183,15 @@ enum chips { lm90, adm1032, lm99, lm86, max6657, max6659, adt7461, max6680,
 #define LM90_HAVE_BROKEN_ALERT	(1 << 7) /* Broken alert		*/
 
 /*
+ * Thermal framework
+ */
+enum lm90_thresholds {
+	LM90_LOW_THRESHOLDS = 0,	/* threshold 0: low limits */
+	LM90_HIGH_THRESHOLDS,		/* threshold 1: high limits */
+	LM90_NUM_THRESHOLDS
+};
+
+/*
  * Driver data (common to all clients)
  */
 
@@ -377,6 +387,9 @@ struct lm90_data {
 	s16 temp11[TEMP11_REG_NUM];
 	u8 temp_hyst;
 	u16 alarms; /* bitvector (upper 8 bits for max6695/96) */
+
+	struct thermal_sensor *ts_remote;
+	struct thermal_sensor *ts_local;
 };
 
 /*
@@ -1493,12 +1506,151 @@ static irqreturn_t lm90_irq(int irq, void *dev_id)
 	return IRQ_HANDLED;
 }
 
+static int lm90_read_remote_temp(struct thermal_sensor *ts, long *temp)
+{
+	struct i2c_client *client = ts->devdata;
+	struct device *dev = &client->dev;
+
+	_show_temp11(dev, TEMP11_REMOTE_TEMP, (int *)temp);
+
+	return 0;
+}
+
+static int lm90_read_remote_threshold(struct thermal_sensor *ts, int th_index,
+					long *val)
+{
+	struct i2c_client *client = ts->devdata;
+	struct device *dev = &client->dev;
+	int index;
+
+	switch (th_index) {
+	case LM90_LOW_THRESHOLDS:
+		/* remote low limit */
+		index = TEMP11_REMOTE_LOW;
+		break;
+	case LM90_HIGH_THRESHOLDS:
+		/* remote high limit */
+		index = TEMP11_REMOTE_HIGH;
+		break;
+	default:
+		dev_err(dev, "read remote threshold failed.\n");
+		return -EINVAL;
+	}
+
+	_show_temp11(dev, index, (int *)val);
+
+	return 0;
+}
+
+static int lm90_write_remote_threshold(struct thermal_sensor *ts, int th_index,
+					long val)
+{
+	struct i2c_client *client = ts->devdata;
+	struct device *dev = &client->dev;
+	int nr, index;
+
+	switch (th_index) {
+	case LM90_LOW_THRESHOLDS:
+		/* remote low limit */
+		nr = NR_CHAN_0_REMOTE_LOW;
+		index = TEMP11_REMOTE_LOW;
+		break;
+	case LM90_HIGH_THRESHOLDS:
+		/* remote high limit */
+		nr = NR_CHAN_0_REMOTE_HIGH;
+		index = TEMP11_REMOTE_HIGH;
+		break;
+	default:
+		dev_err(dev, "write remote threshold failed.\n");
+		return -EINVAL;
+	}
+
+	_set_temp11(dev, nr, index, val);
+
+	return 0;
+}
+
+static struct thermal_sensor_ops remote_ops = {
+	.get_temp = lm90_read_remote_temp,
+	.get_threshold = lm90_read_remote_threshold,
+	.set_threshold = lm90_write_remote_threshold,
+};
+
+static int lm90_read_local_temp(struct thermal_sensor *ts, long *temp)
+{
+	struct i2c_client *client = ts->devdata;
+	struct device *dev = &client->dev;
+
+	_show_temp11(dev, TEMP11_LOCAL_TEMP, (int *)temp);
+
+	return 0;
+}
+
+static int lm90_read_local_threshold(struct thermal_sensor *ts, int th_index,
+					long *val)
+{
+	struct i2c_client *client = ts->devdata;
+	struct device *dev = &client->dev;
+	int index;
+
+	switch (th_index) {
+	case LM90_LOW_THRESHOLDS:
+		/* local low limit */
+		index = TEMP8_LOCAL_LOW;
+		break;
+	case LM90_HIGH_THRESHOLDS:
+		/* local high limit */
+		index = TEMP8_LOCAL_HIGH;
+		break;
+	default:
+		dev_err(dev, "read local threshold failed.\n");
+		return -EINVAL;
+	}
+
+	_show_temp8(dev, index, (int *)val);
+
+	return 0;
+}
+
+static int lm90_write_local_threshold(struct thermal_sensor *ts, int th_index,
+					long val)
+{
+	struct i2c_client *client = ts->devdata;
+	struct device *dev = &client->dev;
+	int index;
+
+	switch (th_index) {
+	case LM90_LOW_THRESHOLDS:
+		/* local low limit */
+		index = TEMP8_LOCAL_LOW;
+		break;
+	case LM90_HIGH_THRESHOLDS:
+		/* local high limit */
+		index = TEMP8_LOCAL_HIGH;
+		break;
+	default:
+		dev_err(dev, "write local threshold failed.\n");
+		return -EINVAL;
+	}
+
+	_set_temp8(dev, index, val);
+
+	return 0;
+}
+
+static struct thermal_sensor_ops local_ops = {
+	.get_temp = lm90_read_local_temp,
+	.get_threshold = lm90_read_local_threshold,
+	.set_threshold = lm90_write_local_threshold,
+};
+
 static int lm90_probe(struct i2c_client *client,
 		      const struct i2c_device_id *id)
 {
 	struct device *dev = &client->dev;
 	struct i2c_adapter *adapter = to_i2c_adapter(dev->parent);
 	struct lm90_data *data;
+	struct node_args np_args;
 	int err;
 
 	data = devm_kzalloc(&client->dev, sizeof(struct lm90_data), GFP_KERNEL);
@@ -1576,12 +1728,38 @@ static int lm90_probe(struct i2c_client *client,
 				       "lm90", data);
 		if (err < 0) {
 			dev_err(dev, "cannot request interrupt\n");
-			goto exit_remove_files;
+			goto exit_unregister_hwmon;
 		}
 	}
 
+	np_args.np = dev->of_node;
+	np_args.index = 0;
+	data->ts_remote = thermal_sensor_register("lm90_remote",
+						LM90_NUM_THRESHOLDS,
+						&np_args,
+						&remote_ops, client);
+	if (IS_ERR(data->ts_remote)) {
+		dev_err(dev, "cannot register sensor to thermal framework\n");
+		err = -EINVAL;
+		goto exit_unregister_hwmon;
+	}
+
+	np_args.index = 1;
+	data->ts_local = thermal_sensor_register("lm90_local",
+						LM90_NUM_THRESHOLDS,
+						&np_args,
+						&local_ops, client);
+
+	if (IS_ERR(data->ts_local)) {
+		dev_err(dev, "cannot register sensor to thermal framework\n");
+		err = -EINVAL;
+		goto exit_unregister_hwmon;
+	}
+
 	return 0;
 
+exit_unregister_hwmon:
+	hwmon_device_unregister(data->hwmon_dev);
 exit_remove_files:
 	lm90_remove_files(client, data);
 exit_restore:
@@ -1594,6 +1772,8 @@ static int lm90_remove(struct i2c_client *client)
 	struct lm90_data *data = i2c_get_clientdata(client);
 
 	free_irq(client->irq, data);
+	thermal_sensor_unregister(data->ts_remote);
+	thermal_sensor_unregister(data->ts_local);
 	hwmon_device_unregister(data->hwmon_dev);
 	lm90_remove_files(client, data);
 	lm90_restore_conf(client, data);
-- 
1.7.9.5