hwmon: (lm90) Add support for max6695 and max6696

Signed-off-by: Guenter Roeck <guenter.roeck@ericsson.com>
Signed-off-by: Jean Delvare <khali@linux-fr.org>

Documentation/hwmon/lm90

@@ -84,6 +84,17 @@ Supported chips:
     Addresses scanned: I2C 0x4c
     Datasheet: Publicly available at the Maxim website
                http://www.maxim-ic.com/quick_view2.cfm/qv_pk/3500
+  * Maxim MAX6695
+    Prefix: 'max6695'
+    Addresses scanned: I2C 0x18
+    Datasheet: Publicly available at the Maxim website
+               http://www.maxim-ic.com/datasheet/index.mvp/id/4199
+  * Maxim MAX6696
+    Prefix: 'max6695'
+    Addresses scanned: I2C 0x18, 0x19, 0x1a, 0x29, 0x2a, 0x2b,
+                           0x4c, 0x4d and 0x4e
+    Datasheet: Publicly available at the Maxim website
+               http://www.maxim-ic.com/datasheet/index.mvp/id/4199
   * Winbond/Nuvoton W83L771AWG/ASG
     Prefix: 'w83l771'
     Addresses scanned: I2C 0x4c
@@ -152,6 +163,12 @@ MAX6680 and MAX6681:
   * Selectable address
   * Remote sensor type selection
 
+MAX6695 and MAX6696:
+  * Better local resolution
+  * Selectable address (max6696)
+  * Second critical temperature limit
+  * Two remote sensors
+
 W83L771AWG/ASG
   * The AWG and ASG variants only differ in package format.
   * Filter and alert configuration register at 0xBF

drivers/hwmon/Kconfig

@@ -614,8 +614,8 @@ config SENSORS_LM90
 	  If you say yes here you get support for National Semiconductor LM90,
 	  LM86, LM89 and LM99, Analog Devices ADM1032 and ADT7461, Maxim
 	  MAX6646, MAX6647, MAX6648, MAX6649, MAX6657, MAX6658, MAX6659,
-	  MAX6680, MAX6681 and MAX6692, and Winbond/Nuvoton W83L771AWG/ASG
-	  sensor chips.
+	  MAX6680, MAX6681, MAX6692, MAX6695, MAX6696, and Winbond/Nuvoton
+	  W83L771AWG/ASG sensor chips.
 
 	  This driver can also be built as a module.  If so, the module
 	  will be called lm90.

drivers/hwmon/lm90.c

@@ -44,6 +44,11 @@
  * chips. The MAX6680 and MAX6681 only differ in the pinout so they can
  * be treated identically.
  *
+ * This driver also supports the MAX6695 and MAX6696, two other sensor
+ * chips made by Maxim. These are also quite similar to other Maxim
+ * chips, but support three temperature sensors instead of two. MAX6695
+ * and MAX6696 only differ in the pinout so they can be treated identically.
+ *
  * This driver also supports the ADT7461 chip from Analog Devices.
  * It's supported in both compatibility and extended mode. It is mostly
  * compatible with LM90 except for a data format difference for the
@@ -96,7 +101,7 @@ static const unsigned short normal_i2c[] = {
 	0x18, 0x19, 0x1a, 0x29, 0x2a, 0x2b, 0x4c, 0x4d, 0x4e, I2C_CLIENT_END };
 
 enum chips { lm90, adm1032, lm99, lm86, max6657, max6659, adt7461, max6680,
-	max6646, w83l771 };
+	max6646, w83l771, max6696 };
 
 /*
  * The LM90 registers
@@ -137,9 +142,10 @@ enum chips { lm90, adm1032, lm99, lm86, max6657, max6659, adt7461, max6680,
 #define LM90_REG_R_TCRIT_HYST		0x21
 #define LM90_REG_W_TCRIT_HYST		0x21
 
-/* MAX6646/6647/6649/6657/6658/6659 registers */
+/* MAX6646/6647/6649/6657/6658/6659/6695/6696 registers */
 
 #define MAX6657_REG_R_LOCAL_TEMPL	0x11
+#define MAX6696_REG_R_STATUS2		0x12
 #define MAX6659_REG_R_REMOTE_EMERG	0x16
 #define MAX6659_REG_W_REMOTE_EMERG	0x16
 #define MAX6659_REG_R_LOCAL_EMERG	0x17
@@ -154,6 +160,8 @@ enum chips { lm90, adm1032, lm99, lm86, max6657, max6659, adt7461, max6680,
 #define LM90_HAVE_LOCAL_EXT	(1 << 2) /* extended local temperature	*/
 #define LM90_HAVE_REM_LIMIT_EXT	(1 << 3) /* extended remote limit	*/
 #define LM90_HAVE_EMERGENCY	(1 << 4) /* 3rd upper (emergency) limit	*/
+#define LM90_HAVE_EMERGENCY_ALARM (1 << 5)/* emergency alarm		*/
+#define LM90_HAVE_TEMP3		(1 << 6) /* 3rd temperature sensor	*/
 
 /*
  * Functions declaration
@@ -166,6 +174,9 @@ static void lm90_init_client(struct i2c_client *client);
 static void lm90_alert(struct i2c_client *client, unsigned int flag);
 static int lm90_remove(struct i2c_client *client);
 static struct lm90_data *lm90_update_device(struct device *dev);
+static inline void lm90_select_remote_channel(struct i2c_client *client,
+					      struct lm90_data *data,
+					      int channel);
 
 /*
  * Driver data (common to all clients)
@@ -186,6 +197,8 @@ static const struct i2c_device_id lm90_id[] = {
 	{ "max6659", max6659 },
 	{ "max6680", max6680 },
 	{ "max6681", max6680 },
+	{ "max6695", max6696 },
+	{ "max6696", max6696 },
 	{ "w83l771", w83l771 },
 	{ }
 };
@@ -217,22 +230,29 @@ struct lm90_data {
 	int flags;
 
 	u8 config_orig;		/* Original configuration register value */
-	u8 alert_alarms;	/* Which alarm bits trigger ALERT# */
+	u16 alert_alarms;	/* Which alarm bits trigger ALERT# */
+				/* Upper 8 bits for max6695/96 */
 
 	/* registers values */
-	s8 temp8[6];	/* 0: local low limit
+	s8 temp8[8];	/* 0: local low limit
 			   1: local high limit
 			   2: local critical limit
 			   3: remote critical limit
-			   4: local emergency limit (max6659 only)
-			   5: remote emergency limit (max6659 only) */
-	s16 temp11[5];	/* 0: remote input
+			   4: local emergency limit (max6659 and max6695/96)
+			   5: remote emergency limit (max6659 and max6695/96)
+			   6: remote 2 critical limit (max6695/96 only)
+			   7: remote 2 emergency limit (max6695/96 only) */
+	s16 temp11[8];	/* 0: remote input
 			   1: remote low limit
 			   2: remote high limit
-			   3: remote offset (except max6646 and max6657/58/59)
-			   4: local input */
+			   3: remote offset (except max6646, max6657/58/59,
+					     and max6695/96)
+			   4: local input
+			   5: remote 2 input (max6695/96 only)
+			   6: remote 2 low limit (max6695/96 only)
+			   7: remote 2 high limit (ma6695/96 only) */
 	u8 temp_hyst;
-	u8 alarms; /* bitvector */
+	u16 alarms; /* bitvector (upper 8 bits for max6695/96) */
 };
 
 /*
@@ -390,13 +410,15 @@ static ssize_t show_temp8(struct device *dev, struct device_attribute *devattr,
 static ssize_t set_temp8(struct device *dev, struct device_attribute *devattr,
 			 const char *buf, size_t count)
 {
-	static const u8 reg[6] = {
+	static const u8 reg[8] = {
 		LM90_REG_W_LOCAL_LOW,
 		LM90_REG_W_LOCAL_HIGH,
 		LM90_REG_W_LOCAL_CRIT,
 		LM90_REG_W_REMOTE_CRIT,
 		MAX6659_REG_W_LOCAL_EMERG,
 		MAX6659_REG_W_REMOTE_EMERG,
+		LM90_REG_W_REMOTE_CRIT,
+		MAX6659_REG_W_REMOTE_EMERG,
 	};
 
 	struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
@@ -421,7 +443,11 @@ static ssize_t set_temp8(struct device *dev, struct device_attribute *devattr,
 		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;
 }
@@ -453,10 +479,13 @@ static ssize_t set_temp11(struct device *dev, struct device_attribute *devattr,
 	struct {
 		u8 high;
 		u8 low;
-	} reg[3] = {
-		{ LM90_REG_W_REMOTE_LOWH, LM90_REG_W_REMOTE_LOWL },
-		{ LM90_REG_W_REMOTE_HIGHH, LM90_REG_W_REMOTE_HIGHL },
-		{ LM90_REG_W_REMOTE_OFFSH, LM90_REG_W_REMOTE_OFFSL }
+		int channel;
+	} reg[5] = {
+		{ LM90_REG_W_REMOTE_LOWH, LM90_REG_W_REMOTE_LOWL, 0 },
+		{ LM90_REG_W_REMOTE_HIGHH, LM90_REG_W_REMOTE_HIGHL, 0 },
+		{ LM90_REG_W_REMOTE_OFFSH, LM90_REG_W_REMOTE_OFFSL, 0 },
+		{ LM90_REG_W_REMOTE_LOWH, LM90_REG_W_REMOTE_LOWL, 1 },
+		{ LM90_REG_W_REMOTE_HIGHH, LM90_REG_W_REMOTE_HIGHL, 1 }
 	};
 
 	struct sensor_device_attribute_2 *attr = to_sensor_dev_attr_2(devattr);
@@ -485,11 +514,14 @@ static ssize_t set_temp11(struct device *dev, struct device_attribute *devattr,
 	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);
+
 	mutex_unlock(&data->update_lock);
 	return count;
 }
@@ -643,6 +675,62 @@ static const struct attribute_group lm90_emergency_group = {
 	.attrs = lm90_emergency_attributes,
 };
 
+static SENSOR_DEVICE_ATTR(temp1_emergency_alarm, S_IRUGO, show_alarm, NULL, 15);
+static SENSOR_DEVICE_ATTR(temp2_emergency_alarm, S_IRUGO, show_alarm, NULL, 13);
+
+static struct attribute *lm90_emergency_alarm_attributes[] = {
+	&sensor_dev_attr_temp1_emergency_alarm.dev_attr.attr,
+	&sensor_dev_attr_temp2_emergency_alarm.dev_attr.attr,
+	NULL
+};
+
+static const struct attribute_group lm90_emergency_alarm_group = {
+	.attrs = lm90_emergency_alarm_attributes,
+};
+
+/*
+ * Additional attributes for devices with 3 temperature sensors
+ */
+static SENSOR_DEVICE_ATTR_2(temp3_input, S_IRUGO, show_temp11, NULL, 0, 5);
+static SENSOR_DEVICE_ATTR_2(temp3_min, S_IWUSR | S_IRUGO, show_temp11,
+	set_temp11, 3, 6);
+static SENSOR_DEVICE_ATTR_2(temp3_max, S_IWUSR | S_IRUGO, show_temp11,
+	set_temp11, 4, 7);
+static SENSOR_DEVICE_ATTR(temp3_crit, S_IWUSR | S_IRUGO, show_temp8,
+	set_temp8, 6);
+static SENSOR_DEVICE_ATTR(temp3_crit_hyst, S_IRUGO, show_temphyst, NULL, 6);
+static SENSOR_DEVICE_ATTR(temp3_emergency, S_IWUSR | S_IRUGO, show_temp8,
+	set_temp8, 7);
+static SENSOR_DEVICE_ATTR(temp3_emergency_hyst, S_IRUGO, show_temphyst,
+			  NULL, 7);
+
+static SENSOR_DEVICE_ATTR(temp3_crit_alarm, S_IRUGO, show_alarm, NULL, 9);
+static SENSOR_DEVICE_ATTR(temp3_fault, S_IRUGO, show_alarm, NULL, 10);
+static SENSOR_DEVICE_ATTR(temp3_min_alarm, S_IRUGO, show_alarm, NULL, 11);
+static SENSOR_DEVICE_ATTR(temp3_max_alarm, S_IRUGO, show_alarm, NULL, 12);
+static SENSOR_DEVICE_ATTR(temp3_emergency_alarm, S_IRUGO, show_alarm, NULL, 14);
+
+static struct attribute *lm90_temp3_attributes[] = {
+	&sensor_dev_attr_temp3_input.dev_attr.attr,
+	&sensor_dev_attr_temp3_min.dev_attr.attr,
+	&sensor_dev_attr_temp3_max.dev_attr.attr,
+	&sensor_dev_attr_temp3_crit.dev_attr.attr,
+	&sensor_dev_attr_temp3_crit_hyst.dev_attr.attr,
+	&sensor_dev_attr_temp3_emergency.dev_attr.attr,
+	&sensor_dev_attr_temp3_emergency_hyst.dev_attr.attr,
+
+	&sensor_dev_attr_temp3_fault.dev_attr.attr,
+	&sensor_dev_attr_temp3_min_alarm.dev_attr.attr,
+	&sensor_dev_attr_temp3_max_alarm.dev_attr.attr,
+	&sensor_dev_attr_temp3_crit_alarm.dev_attr.attr,
+	&sensor_dev_attr_temp3_emergency_alarm.dev_attr.attr,
+	NULL
+};
+
+static const struct attribute_group lm90_temp3_group = {
+	.attrs = lm90_temp3_attributes,
+};
+
 /* pec used for ADM1032 only */
 static ssize_t show_pec(struct device *dev, struct device_attribute *dummy,
 			char *buf)
@@ -720,6 +808,30 @@ static int lm90_read_reg(struct i2c_client *client, u8 reg, u8 *value)
 	return 0;
 }
 
+/*
+ * client->update_lock must be held when calling this function (unless we are
+ * in detection or initialization steps), and while a remote channel other
+ * than channel 0 is selected. Also, calling code must make sure to re-select
+ * external channel 0 before releasing the lock. This is necessary because
+ * 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)
+{
+	u8 config;
+
+	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);
+	}
+}
+
 /* Return 0 if detection is successful, -ENODEV otherwise */
 static int lm90_detect(struct i2c_client *new_client,
 		       struct i2c_board_info *info)
@@ -794,6 +906,23 @@ static int lm90_detect(struct i2c_client *new_client,
 		}
 	} else
 	if (man_id == 0x4D) { /* Maxim */
+		int reg_emerg, reg_emerg2, reg_status2;
+
+		/*
+		 * We read MAX6659_REG_R_REMOTE_EMERG twice, and re-read
+		 * LM90_REG_R_MAN_ID in between. If MAX6659_REG_R_REMOTE_EMERG
+		 * exists, both readings will reflect the same value. Otherwise,
+		 * the readings will be different.
+		 */
+		if ((reg_emerg = i2c_smbus_read_byte_data(new_client,
+						MAX6659_REG_R_REMOTE_EMERG)) < 0
+		 || i2c_smbus_read_byte_data(new_client, LM90_REG_R_MAN_ID) < 0
+		 || (reg_emerg2 = i2c_smbus_read_byte_data(new_client,
+						MAX6659_REG_R_REMOTE_EMERG)) < 0
+		 || (reg_status2 = i2c_smbus_read_byte_data(new_client,
+						MAX6696_REG_R_STATUS2)) < 0)
+			return -ENODEV;
+
 		/*
 		 * The MAX6657, MAX6658 and MAX6659 do NOT have a chip_id
 		 * register. Reading from that address will return the last
@@ -816,6 +945,24 @@ static int lm90_detect(struct i2c_client *new_client,
 			else
 				name = "max6659";
 		} else
+		/*
+		 * Even though MAX6695 and MAX6696 do not have a chip ID
+		 * register, reading it returns 0x01. Bit 4 of the config1
+		 * register is unused and should return zero when read. Bit 0 of
+		 * the status2 register is unused and should return zero when
+		 * read.
+		 *
+		 * MAX6695 and MAX6696 have an additional set of temperature
+		 * limit registers. We can detect those chips by checking if
+		 * one of those registers exists.
+		 */
+		if (chip_id == 0x01
+		 && (reg_config1 & 0x10) == 0x00
+		 && (reg_status2 & 0x01) == 0x00
+		 && reg_emerg == reg_emerg2
+		 && reg_convrate <= 0x07) {
+			name = "max6696";
+		} else
 		/*
 		 * The chip_id register of the MAX6680 and MAX6681 holds the
 		 * revision of the chip. The lowest bit of the config1 register
@@ -861,6 +1008,11 @@ static int lm90_detect(struct i2c_client *new_client,
 
 static void lm90_remove_files(struct i2c_client *client, struct lm90_data *data)
 {
+	if (data->flags & LM90_HAVE_TEMP3)
+		sysfs_remove_group(&client->dev.kobj, &lm90_temp3_group);
+	if (data->flags & LM90_HAVE_EMERGENCY_ALARM)
+		sysfs_remove_group(&client->dev.kobj,
+				   &lm90_emergency_alarm_group);
 	if (data->flags & LM90_HAVE_EMERGENCY)
 		sysfs_remove_group(&client->dev.kobj,
 				   &lm90_emergency_group);
@@ -901,6 +1053,9 @@ static int lm90_probe(struct i2c_client *new_client,
 	case lm86:
 		data->alert_alarms = 0x7b;
 		break;
+	case max6696:
+		data->alert_alarms = 0x187c;
+		break;
 	default:
 		data->alert_alarms = 0x7c;
 		break;
@@ -908,20 +1063,24 @@ static int lm90_probe(struct i2c_client *new_client,
 
 	/* Set chip capabilities */
 	if (data->kind != max6657 && data->kind != max6659
-	    && data->kind != max6646)
+	    && data->kind != max6646 && data->kind != max6696)
 		data->flags |= LM90_HAVE_OFFSET;
 
 	if (data->kind == max6657 || data->kind == max6659
-	    || data->kind == max6646)
+	    || data->kind == max6646 || data->kind == max6696)
 		data->flags |= LM90_HAVE_LOCAL_EXT;
 
 	if (data->kind != max6657 && data->kind != max6659
-	    && data->kind != max6646 && data->kind != max6680)
+	    && data->kind != max6646 && data->kind != max6680
+	    && data->kind != max6696)
 		data->flags |= LM90_HAVE_REM_LIMIT_EXT;
 
-	if (data->kind == max6659)
+	if (data->kind == max6659 || data->kind == max6696)
 		data->flags |= LM90_HAVE_EMERGENCY;
 
+	if (data->kind == max6696)
+		data->flags |= LM90_HAVE_EMERGENCY_ALARM | LM90_HAVE_TEMP3;
+
 	/* Initialize the LM90 chip */
 	lm90_init_client(new_client);
 
@@ -946,6 +1105,18 @@ static int lm90_probe(struct i2c_client *new_client,
 		if (err)
 			goto exit_remove_files;
 	}
+	if (data->flags & LM90_HAVE_EMERGENCY_ALARM) {
+		err = sysfs_create_group(&new_client->dev.kobj,
+					 &lm90_emergency_alarm_group);
+		if (err)
+			goto exit_remove_files;
+	}
+	if (data->flags & LM90_HAVE_TEMP3) {
+		err = sysfs_create_group(&new_client->dev.kobj,
+					 &lm90_temp3_group);
+		if (err)
+			goto exit_remove_files;
+	}
 
 	data->hwmon_dev = hwmon_device_register(&new_client->dev);
 	if (IS_ERR(data->hwmon_dev)) {
@@ -993,6 +1164,12 @@ static void lm90_init_client(struct i2c_client *client)
 	if (data->kind == max6680)
 		config |= 0x18;
 
+	/*
+	 * Select external channel 0 for max6695/96
+	 */
+	if (data->kind == max6696)
+		config &= ~0x08;
+
 	config &= 0xBF;	/* run */
 	if (config != data->config_orig) /* Only write if changed */
 		i2c_smbus_write_byte_data(client, LM90_REG_W_CONFIG1, config);
@@ -1016,10 +1193,14 @@ static int lm90_remove(struct i2c_client *client)
 static void lm90_alert(struct i2c_client *client, unsigned int flag)
 {
 	struct lm90_data *data = i2c_get_clientdata(client);
-	u8 config, alarms;
+	u8 config, alarms, alarms2 = 0;
 
 	lm90_read_reg(client, LM90_REG_R_STATUS, &alarms);
-	if ((alarms & 0x7f) == 0) {
+
+	if (data->kind == max6696)
+		lm90_read_reg(client, MAX6696_REG_R_STATUS2, &alarms2);
+
+	if ((alarms & 0x7f) == 0 && (alarms2 & 0xfe) == 0) {
 		dev_info(&client->dev, "Everything OK\n");
 	} else {
 		if (alarms & 0x61)
@@ -1032,6 +1213,10 @@ static void lm90_alert(struct i2c_client *client, unsigned int flag)
 			dev_warn(&client->dev,
 				 "temp%d diode open, please check!\n", 2);
 
+		if (alarms2 & 0x18)
+			dev_warn(&client->dev,
+				 "temp%d out of range, please check!\n", 3);
+
 		/* Disable ALERT# output, because these chips don't implement
 		  SMBus alert correctly; they should only hold the alert line
 		  low briefly. */
@@ -1087,6 +1272,7 @@ static struct lm90_data *lm90_update_device(struct device *dev)
 	if (time_after(jiffies, data->last_updated + HZ / 2 + HZ / 10)
 	 || !data->valid) {
 		u8 h, l;
+		u8 alarms;
 
 		dev_dbg(&client->dev, "Updating lm90 data.\n");
 		lm90_read_reg(client, LM90_REG_R_LOCAL_LOW, &data->temp8[0]);
@@ -1135,7 +1321,27 @@ static struct lm90_data *lm90_update_device(struct device *dev)
 			lm90_read_reg(client, MAX6659_REG_R_REMOTE_EMERG,
 				      &data->temp8[5]);
 		}
-		lm90_read_reg(client, LM90_REG_R_STATUS, &data->alarms);
+		lm90_read_reg(client, LM90_REG_R_STATUS, &alarms);
+		data->alarms = alarms;	/* save as 16 bit value */
+
+		if (data->kind == max6696) {
+			lm90_select_remote_channel(client, data, 1);
+			lm90_read_reg(client, LM90_REG_R_REMOTE_CRIT,
+				      &data->temp8[6]);
+			lm90_read_reg(client, MAX6659_REG_R_REMOTE_EMERG,
+				      &data->temp8[7]);
+			lm90_read16(client, LM90_REG_R_REMOTE_TEMPH,
+				    LM90_REG_R_REMOTE_TEMPL, &data->temp11[5]);
+			if (!lm90_read_reg(client, LM90_REG_R_REMOTE_LOWH, &h))
+				data->temp11[6] = h << 8;
+			if (!lm90_read_reg(client, LM90_REG_R_REMOTE_HIGHH, &h))
+				data->temp11[7] = h << 8;
+			lm90_select_remote_channel(client, data, 0);
+
+			if (!lm90_read_reg(client, MAX6696_REG_R_STATUS2,
+					   &alarms))
+				data->alarms |= alarms << 8;
+		}
 
 		/* Re-enable ALERT# output if it was originally enabled and
 		 * relevant alarms are all clear */