apm821xx: lm90 add thermal sensor interface support for device tree

 From 912-hwmon-lm90-expose-to-thermal-fw-via-DT.patch:
"This patch adds to lm90 temperature sensor the possibility
to expose itself as thermal zone device, registered on the
thermal framework.

The thermal zone is built only if a device tree node
describing a thermal zone for this sensor is present
inside the lm90 DT node. Otherwise, the driver behavior
will be the same."

Signed-off-by: Christian Lamparter <chunkeey@gmail.com>

2 files changed, 453 insertions, 0 deletions

diff --git a/target/linux/apm821xx/patches-4.4/911-hwmon-lm90-split-set-and-show-temp-as-common-codes.patch b/target/linux/apm821xx/patches-4.4/911-hwmon-lm90-split-set-and-show-temp-as-common-codes.patch
new file mode 100644
index 0000000..a2e38c5
--- /dev/null
+++ b/target/linux/apm821xx/patches-4.4/911-hwmon-lm90-split-set-and-show-temp-as-common-codes.patch
@@ -0,0 +1,302 @@
+From: Wei Ni <wni@nvidia.com>
+Subject: hwmon: lm90: split set and show temp as common codes
+
+Split set and show temp codes as common functions, so we can use
+it directly when implement linux thermal framework.
+And handle error return value for the lm90_select_remote_channel
+and write_tempx, then set_temp8 and set_temp11 could return it
+to user-space.
+
+Discussed in:
+http://www.spinics.net/lists/linux-tegra/msg14020.html .
+Applied with Jean.
+
+BUG=chrome-os-partner:30834
+TEST=None
+
+Signed-off-by: Wei Ni <wni@nvidia.com>
+Signed-off-by: Jean Delvare <khali@linux-fr.org>
+Reviewed-on: https://chromium-review.googlesource.com/175114
+Tested-by: Wei Ni <wni.nvidia@gmail.com>
+Commit-Queue: Dylan Reid <dgreid@chromium.org>
+Reviewed-by: Dylan Reid <dgreid@chromium.org>
+(cherry picked from commit 614a96decdc7a3784128c9f21c5471367e2c627d)
+Change-Id: Idbe3948812c6737cba94810cd147c29cc527c3cf
+Reviewed-on: https://chromium-review.googlesource.com/212413
+Reviewed-by: Olof Johansson <olofj@chromium.org>
+Commit-Queue: Olof Johansson <olofj@chromium.org>
+---
+diff --git a/drivers/hwmon/lm90.c b/drivers/hwmon/lm90.c
+index c9ff08d..fb9e224 100644
+--- a/drivers/hwmon/lm90.c
++++ b/drivers/hwmon/lm90.c
+@@ -473,20 +473,29 @@
+  * various registers have different meanings as a result of selecting a
+  * non-default remote channel.
+  */
+-static inline void lm90_select_remote_channel(struct i2c_client *client,
+-					      struct lm90_data *data,
+-					      int channel)
++static inline int lm90_select_remote_channel(struct i2c_client *client,
++					     struct lm90_data *data,
++					     int channel)
+ {
+ 	u8 config;
++	int err;
+ 
+ 	if (data->kind == max6696) {
+ 		lm90_read_reg(client, LM90_REG_R_CONFIG1, &config);
+ 		config &= ~0x08;
+ 		if (channel)
+ 			config |= 0x08;
+-		i2c_smbus_write_byte_data(client, LM90_REG_W_CONFIG1,
+-					  config);
++		err = i2c_smbus_write_byte_data(client, LM90_REG_W_CONFIG1,
++						config);
++		if (err < 0) {
++			dev_err(&client->dev,
++				"Failed to select remote channel %d, err %d\n",
++				channel, err);
++			return err;
++		}
+ 	}
++
++	return 0;
+ }
+ 
+ /*
+@@ -759,29 +768,34 @@
+  * Sysfs stuff
+  */
+ 
+-static ssize_t show_temp8(struct device *dev, struct device_attribute *devattr,
+-			  char *buf)
++static int read_temp8(struct device *dev, int index)
+ {
+-	struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
+ 	struct lm90_data *data = lm90_update_device(dev);
+ 	int temp;
+ 
+ 	if (data->kind == adt7461 || data->kind == tmp451)
+-		temp = temp_from_u8_adt7461(data, data->temp8[attr->index]);
++		temp = temp_from_u8_adt7461(data, data->temp8[index]);
+ 	else if (data->kind == max6646)
+-		temp = temp_from_u8(data->temp8[attr->index]);
++		temp = temp_from_u8(data->temp8[index]);
+ 	else
+-		temp = temp_from_s8(data->temp8[attr->index]);
++		temp = temp_from_s8(data->temp8[index]);
+ 
+ 	/* +16 degrees offset for temp2 for the LM99 */
+-	if (data->kind == lm99 && attr->index == 3)
++	if (data->kind == lm99 && index == 3)
+ 		temp += 16000;
+ 
+-	return sprintf(buf, "%d\n", temp);
++	return temp;
+ }
+ 
+-static ssize_t set_temp8(struct device *dev, struct device_attribute *devattr,
+-			 const char *buf, size_t count)
++static ssize_t show_temp8(struct device *dev, struct device_attribute *devattr,
++			  char *buf)
++{
++	struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
++
++	return sprintf(buf, "%d\n", read_temp8(dev, attr->index));
++}
++
++static int write_temp8(struct device *dev, int index, long val)
+ {
+ 	static const u8 reg[TEMP8_REG_NUM] = {
+ 		LM90_REG_W_LOCAL_LOW,
+@@ -794,10 +808,37 @@
+ 		MAX6659_REG_W_REMOTE_EMERG,
+ 	};
+ 
+-	struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
+ 	struct lm90_data *data = dev_get_drvdata(dev);
+ 	struct i2c_client *client = data->client;
+-	int nr = attr->index;
++	int err;
++
++	/* +16 degrees offset for temp2 for the LM99 */
++	if (data->kind == lm99 && index == 3)
++		val -= 16000;
++
++	mutex_lock(&data->update_lock);
++	if (data->kind == adt7461 || data->kind == tmp451)
++		data->temp8[index] = temp_to_u8_adt7461(data, val);
++	else if (data->kind == max6646)
++		data->temp8[index] = temp_to_u8(val);
++	else
++		data->temp8[index] = temp_to_s8(val);
++
++	if ((err = lm90_select_remote_channel(client, data, index >= 6)) ||
++	    (err = i2c_smbus_write_byte_data(client, reg[index],
++					     data->temp8[index])) ||
++	    (err = lm90_select_remote_channel(client, data, 0)))
++		dev_err(dev, "write_temp8 failed, err %d\n", err);
++	mutex_unlock(&data->update_lock);
++
++	return err;
++}
++
++static ssize_t set_temp8(struct device *dev, struct device_attribute *devattr,
++			 const char *buf, size_t count)
++{
++	struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
++	int index = attr->index;
+ 	long val;
+ 	int err;
+ 
+@@ -805,49 +846,41 @@
+ 	if (err < 0)
+ 		return err;
+ 
+-	/* +16 degrees offset for temp2 for the LM99 */
+-	if (data->kind == lm99 && attr->index == 3)
+-		val -= 16000;
++	err = write_temp8(dev, index, val);
++	if (err < 0)
++		return err;
+ 
+-	mutex_lock(&data->update_lock);
+-	if (data->kind == adt7461 || data->kind == tmp451)
+-		data->temp8[nr] = temp_to_u8_adt7461(data, val);
+-	else if (data->kind == max6646)
+-		data->temp8[nr] = temp_to_u8(val);
+-	else
+-		data->temp8[nr] = temp_to_s8(val);
+-
+-	lm90_select_remote_channel(client, data, nr >= 6);
+-	i2c_smbus_write_byte_data(client, reg[nr], data->temp8[nr]);
+-	lm90_select_remote_channel(client, data, 0);
+-
+-	mutex_unlock(&data->update_lock);
+ 	return count;
++}
++
++static int read_temp11(struct device *dev, int index)
++{
++	struct lm90_data *data = lm90_update_device(dev);
++	int temp;
++
++	if (data->kind == adt7461 || data->kind == tmp451)
++		temp = temp_from_u16_adt7461(data, data->temp11[index]);
++	else if (data->kind == max6646)
++		temp = temp_from_u16(data->temp11[index]);
++	else
++		temp = temp_from_s16(data->temp11[index]);
++
++	/* +16 degrees offset for temp2 for the LM99 */
++	if (data->kind == lm99 && index <= 2)
++		temp += 16000;
++
++	return temp;
+ }
+ 
+ static ssize_t show_temp11(struct device *dev, struct device_attribute *devattr,
+ 			   char *buf)
+ {
+ 	struct sensor_device_attribute_2 *attr = to_sensor_dev_attr_2(devattr);
+-	struct lm90_data *data = lm90_update_device(dev);
+-	int temp;
+ 
+-	if (data->kind == adt7461 || data->kind == tmp451)
+-		temp = temp_from_u16_adt7461(data, data->temp11[attr->index]);
+-	else if (data->kind == max6646)
+-		temp = temp_from_u16(data->temp11[attr->index]);
+-	else
+-		temp = temp_from_s16(data->temp11[attr->index]);
+-
+-	/* +16 degrees offset for temp2 for the LM99 */
+-	if (data->kind == lm99 &&  attr->index <= 2)
+-		temp += 16000;
+-
+-	return sprintf(buf, "%d\n", temp);
++	return sprintf(buf, "%d\n", read_temp11(dev, attr->index));
+ }
+ 
+-static ssize_t set_temp11(struct device *dev, struct device_attribute *devattr,
+-			  const char *buf, size_t count)
++static int write_temp11(struct device *dev, int nr, int index, long val)
+ {
+ 	struct {
+ 		u8 high;
+@@ -861,17 +894,9 @@
+ 		{ LM90_REG_W_REMOTE_HIGHH, LM90_REG_W_REMOTE_HIGHL, 1 }
+ 	};
+ 
+-	struct sensor_device_attribute_2 *attr = to_sensor_dev_attr_2(devattr);
+ 	struct lm90_data *data = dev_get_drvdata(dev);
+ 	struct i2c_client *client = data->client;
+-	int nr = attr->nr;
+-	int index = attr->index;
+-	long val;
+ 	int err;
+-
+-	err = kstrtol(buf, 10, &val);
+-	if (err < 0)
+-		return err;
+ 
+ 	/* +16 degrees offset for temp2 for the LM99 */
+ 	if (data->kind == lm99 && index <= 2)
+@@ -887,15 +912,50 @@
+ 	else
+ 		data->temp11[index] = temp_to_s8(val) << 8;
+ 
+-	lm90_select_remote_channel(client, data, reg[nr].channel);
+-	i2c_smbus_write_byte_data(client, reg[nr].high,
+-				  data->temp11[index] >> 8);
+-	if (data->flags & LM90_HAVE_REM_LIMIT_EXT)
+-		i2c_smbus_write_byte_data(client, reg[nr].low,
+-					  data->temp11[index] & 0xff);
+-	lm90_select_remote_channel(client, data, 0);
++	err = lm90_select_remote_channel(client, data, reg[nr].channel);
++	if (err)
++		goto error;
++
++	err = i2c_smbus_write_byte_data(client, reg[nr].high,
++					data->temp11[index] >> 8);
++	if (err)
++		goto error;
++
++	if (data->flags & LM90_HAVE_REM_LIMIT_EXT) {
++		err = i2c_smbus_write_byte_data(client, reg[nr].low,
++						data->temp11[index] & 0xff);
++		if (err)
++			goto error;
++	}
++
++	err = lm90_select_remote_channel(client, data, 0);
++
++error:
++	if (err)
++		dev_err(dev, "write_temp11 failed, err %d\n", err);
+ 
+ 	mutex_unlock(&data->update_lock);
++
++	return err;
++}
++
++static ssize_t set_temp11(struct device *dev, struct device_attribute *devattr,
++			  const char *buf, size_t count)
++{
++	struct sensor_device_attribute_2 *attr = to_sensor_dev_attr_2(devattr);
++	int nr = attr->nr;
++	int index = attr->index;
++	long val;
++	int err;
++
++	err = kstrtol(buf, 10, &val);
++	if (err < 0)
++		return err;
++
++	err = write_temp11(dev, nr, index, val);
++	if (err < 0)
++		return err;
++
+ 	return count;
+ }
+ 
diff --git a/target/linux/apm821xx/patches-4.4/912-hwmon-lm90-expose-to-thermal-fw-via-DT.patch b/target/linux/apm821xx/patches-4.4/912-hwmon-lm90-expose-to-thermal-fw-via-DT.patch
new file mode 100644
index 0000000..fe7337b
--- /dev/null
+++ b/target/linux/apm821xx/patches-4.4/912-hwmon-lm90-expose-to-thermal-fw-via-DT.patch
@@ -0,0 +1,151 @@
+From: Wei Ni <wni@nvidia.com>
+Subject: hwmon: lm90: expose to thermal fw via DT nodes
+
+This patch adds to lm90 temperature sensor the possibility
+to expose itself as thermal zone device, registered on the
+thermal framework.
+
+The thermal zone is built only if a device tree node
+describing a thermal zone for this sensor is present
+inside the lm90 DT node. Otherwise, the driver behavior
+will be the same.
+
+Discussed in:
+http://www.gossamer-threads.com/lists/linux/kernel/1992853
+
+BUG=chrome-os-partner:30834
+TEST=Verified. Build and boot up system.
+
+Signed-off-by: Wei Ni <wni@nvidia.com>
+Reviewed-on: https://chromium-review.googlesource.com/181447
+Reviewed-by: Dylan Reid <dgreid@chromium.org>
+Tested-by: Dylan Reid <dgreid@chromium.org>
+Commit-Queue: Dylan Reid <dgreid@chromium.org>
+Change-Id: Id356b94d7e8f4b49ec15e46b17a1fa2ff0cbf8cf
+Reviewed-on: https://chromium-review.googlesource.com/212414
+Tested-by: Wei Ni <wni.nvidia@gmail.com>
+Reviewed-by: Olof Johansson <olofj@chromium.org>
+Commit-Queue: Olof Johansson <olofj@chromium.org>
+---
+diff --git a/drivers/hwmon/lm90.c b/drivers/hwmon/lm90.c
+index fb9e224..c54d3c8 100644
+--- a/drivers/hwmon/lm90.c
++++ b/drivers/hwmon/lm90.c
+@@ -96,6 +96,8 @@
+ #include <linux/sysfs.h>
+ #include <linux/interrupt.h>
+ #include <linux/regulator/consumer.h>
++#include <linux/of.h>
++#include <linux/thermal.h>
+ 
+ /*
+  * Addresses to scan
+@@ -118,6 +120,13 @@
+ 
+ enum chips { lm90, adm1032, lm99, lm86, max6657, max6659, adt7461, max6680,
+ 	max6646, w83l771, max6696, sa56004, g781, tmp451 };
++
++enum sensor_id {
++	LOCAL = 0,
++	REMOTE,
++	REMOTE2,
++	SENSOR_ID_END,
++};
+ 
+ /*
+  * The LM90 registers
+@@ -368,6 +377,7 @@
+ 	struct i2c_client *client;
+ 	struct device *hwmon_dev;
+ 	const struct attribute_group *groups[6];
++	struct thermal_zone_device *tz[SENSOR_ID_END];
+ 	struct mutex update_lock;
+ 	struct regulator *regulator;
+ 	char valid; /* zero until following fields are valid */
+@@ -878,6 +888,24 @@
+ 	struct sensor_device_attribute_2 *attr = to_sensor_dev_attr_2(devattr);
+ 
+ 	return sprintf(buf, "%d\n", read_temp11(dev, attr->index));
++}
++
++static int lm90_read_local_temp(void *dev, int *temp)
++{
++	*temp = read_temp11(dev, 4);
++	return 0;
++}
++
++static int lm90_read_remote_temp(void *dev, int *temp)
++{
++	*temp = read_temp11(dev, 0);
++	return 0;
++}
++
++static int lm90_read_remote2_temp(void *dev, int *temp)
++{
++	*temp = read_temp11(dev, 5);
++	return 0;
+ }
+ 
+ static int write_temp11(struct device *dev, int nr, int index, long val)
+@@ -1150,6 +1238,18 @@
+ 	.attrs = lm90_temp3_attributes,
+ };
+ 
++static const struct thermal_zone_of_device_ops local_temp_sensor = {
++	.get_temp = lm90_read_local_temp,
++};
++
++static const struct thermal_zone_of_device_ops remote_temp_sensor = {
++	.get_temp = lm90_read_remote_temp,
++};
++
++static const struct thermal_zone_of_device_ops remote2_temp_sensor = {
++	.get_temp = lm90_read_remote2_temp,
++};
++
+ /* pec used for ADM1032 only */
+ static ssize_t show_pec(struct device *dev, struct device_attribute *dummy,
+ 			char *buf)
+@@ -1599,6 +1699,30 @@
+ 		}
+ 	}
+ 
++	data->tz[LOCAL] = thermal_zone_of_sensor_register(&client->dev,
++							LOCAL,
++							&client->dev,
++							&local_temp_sensor);
++	if (IS_ERR(data->tz[LOCAL]))
++		data->tz[LOCAL] = NULL;
++
++	data->tz[REMOTE] = thermal_zone_of_sensor_register(&client->dev,
++							REMOTE,
++							&client->dev,
++							&remote_temp_sensor);
++	if (IS_ERR(data->tz[REMOTE]))
++		data->tz[REMOTE] = NULL;
++
++	if (data->flags & LM90_HAVE_TEMP3) {
++		data->tz[REMOTE2] = thermal_zone_of_sensor_register(
++							&client->dev,
++							REMOTE2,
++							&client->dev,
++							&remote2_temp_sensor);
++		if (IS_ERR(data->tz[REMOTE2]))
++			data->tz[REMOTE2] = NULL;
++	}
++
+ 	return 0;
+ 
+ exit_unregister:
+@@ -1674,8 +1726,11 @@
+ 
+ static int lm90_remove(struct i2c_client *client)
+ {
++	int i;
+ 	struct lm90_data *data = i2c_get_clientdata(client);
+ 
++	for (i = 0; i < SENSOR_ID_END; i++)
++		thermal_zone_of_sensor_unregister(&client->dev, data->tz[i]);
+ 	hwmon_device_unregister(data->hwmon_dev);
+ 	device_remove_file(&client->dev, &dev_attr_pec);
+ 	lm90_restore_conf(client, data);