hwmon: (lm63) Add support for update_interval sysfs attribute

The update interval is configurable on LM63 and compatibles. Add support for it. Signed-off-by: Guenter Roeck <linux@roeck-us.net> Signed-off-by: Jean Delvare <khali@linux-fr.org>

hwmon: (lm63) Add support for update_interval sysfs attribute
The update interval is configurable on LM63 and compatibles. Add support for it. Signed-off-by: Guenter Roeck <linux@roeck-us.net> Signed-off-by: Jean Delvare <khali@linux-fr.org>
Guenter Roeck · Jean Delvare
1 parent 94e55df48a
Showing 2 changed files with 93 additions and 5 deletions Side-by-side Diff
Documentation/hwmon/lm63
drivers/hwmon/lm63.c
@@ -61,9 +61,9 @@
 (you cannot define your custom PWM/temperature curve), and mode change isn't
 supported either.
  
-The lm63 driver will not update its values more frequently than every
-second; reading them more often will do no harm, but will return 'old'
-values.
+The lm63 driver will not update its values more frequently than configured with
+the update_interval sysfs attribute; reading them more often will do no harm,
+but will return 'old' values.
  
 The LM64 is effectively an LM63 with GPIO lines. The driver does not
 support these GPIO lines at present.
@@ -61,6 +61,7 @@
  */
  
 #define LM63_REG_CONFIG1		0x03
+#define LM63_REG_CONVRATE		0x04
 #define LM63_REG_CONFIG2		0xBF
 #define LM63_REG_CONFIG_FAN		0x4A
  
@@ -96,6 +97,11 @@
 #define LM96163_REG_REMOTE_TEMP_U_LSB	0x32
 #define LM96163_REG_CONFIG_ENHANCED	0x45
  
+#define LM63_MAX_CONVRATE		9
+
+#define LM63_MAX_CONVRATE_HZ		32
+#define LM96163_MAX_CONVRATE_HZ		26
+
 /*
  * Conversions and various macros
  * For tachometer counts, the LM63 uses 16-bit values.
@@ -132,6 +138,9 @@
 				 (val) >= 127000 ? 127 : \
 				 ((val) + 500) / 1000)
  
+#define UPDATE_INTERVAL(max, rate) \
+			((1000 << (LM63_MAX_CONVRATE - (rate))) / (max))
+
 /*
  * Functions declaration
  */
  
@@ -180,9 +189,12 @@
 	struct mutex update_lock;
 	char valid; /* zero until following fields are valid */
 	unsigned long last_updated; /* in jiffies */
-	int kind;
+	enum chips kind;
 	int temp2_offset;
  
+	int update_interval;	/* in milliseconds */
+	int max_convrate_hz;
+
 	/* registers values */
 	u8 config, config_fan;
 	u16 fan[2];	/* 0: input
@@ -449,6 +461,58 @@
 	return count;
 }
  
+/*
+ * Set conversion rate.
+ * client->update_lock must be held when calling this function.
+ */
+static void lm63_set_convrate(struct i2c_client *client, struct lm63_data *data,
+			      unsigned int interval)
+{
+	int i;
+	unsigned int update_interval;
+
+	/* Shift calculations to avoid rounding errors */
+	interval <<= 6;
+
+	/* find the nearest update rate */
+	update_interval = (1 << (LM63_MAX_CONVRATE + 6)) * 1000
+	  / data->max_convrate_hz;
+	for (i = 0; i < LM63_MAX_CONVRATE; i++, update_interval >>= 1)
+		if (interval >= update_interval * 3 / 4)
+			break;
+
+	i2c_smbus_write_byte_data(client, LM63_REG_CONVRATE, i);
+	data->update_interval = UPDATE_INTERVAL(data->max_convrate_hz, i);
+}
+
+static ssize_t show_update_interval(struct device *dev,
+				    struct device_attribute *attr, char *buf)
+{
+	struct lm63_data *data = dev_get_drvdata(dev);
+
+	return sprintf(buf, "%u\n", data->update_interval);
+}
+
+static ssize_t set_update_interval(struct device *dev,
+				   struct device_attribute *attr,
+				   const char *buf, size_t count)
+{
+	struct i2c_client *client = to_i2c_client(dev);
+	struct lm63_data *data = i2c_get_clientdata(client);
+	unsigned long val;
+	int err;
+
+	err = kstrtoul(buf, 10, &val);
+	if (err)
+		return err;
+
+	mutex_lock(&data->update_lock);
+	lm63_set_convrate(client, data, SENSORS_LIMIT(val, 0, 100000));
+	mutex_unlock(&data->update_lock);
+
+	return count;
+}
+
 static ssize_t show_alarms(struct device *dev, struct device_attribute *dummy,
 			   char *buf)
 {
@@ -499,6 +563,9 @@
 /* Raw alarm file for compatibility */
 static DEVICE_ATTR(alarms, S_IRUGO, show_alarms, NULL);
  
+static DEVICE_ATTR(update_interval, S_IRUGO | S_IWUSR, show_update_interval,
+		   set_update_interval);
+
 static struct attribute *lm63_attributes[] = {
 	&dev_attr_pwm1.attr,
 	&dev_attr_pwm1_enable.attr,
@@ -517,6 +584,7 @@
 	&sensor_dev_attr_temp2_max_alarm.dev_attr.attr,
 	&sensor_dev_attr_temp1_max_alarm.dev_attr.attr,
 	&dev_attr_alarms.attr,
+	&dev_attr_update_interval.attr,
 	NULL
 };
  
@@ -669,6 +737,7 @@
 static void lm63_init_client(struct i2c_client *client)
 {
 	struct lm63_data *data = i2c_get_clientdata(client);
+	u8 convrate;
  
 	data->config = i2c_smbus_read_byte_data(client, LM63_REG_CONFIG1);
 	data->config_fan = i2c_smbus_read_byte_data(client,
@@ -687,6 +756,21 @@
 	if (data->pwm1_freq == 0)
 		data->pwm1_freq = 1;
  
+	switch (data->kind) {
+	case lm63:
+	case lm64:
+		data->max_convrate_hz = LM63_MAX_CONVRATE_HZ;
+		break;
+	case lm96163:
+		data->max_convrate_hz = LM96163_MAX_CONVRATE_HZ;
+		break;
+	}
+	convrate = i2c_smbus_read_byte_data(client, LM63_REG_CONVRATE);
+	if (unlikely(convrate > LM63_MAX_CONVRATE))
+		convrate = LM63_MAX_CONVRATE;
+	data->update_interval = UPDATE_INTERVAL(data->max_convrate_hz,
+						convrate);
+
 	/*
 	 * For LM96163, check if high resolution PWM
 	 * and unsigned temperature format is enabled.
  
@@ -730,10 +814,14 @@
 {
 	struct i2c_client *client = to_i2c_client(dev);
 	struct lm63_data *data = i2c_get_clientdata(client);
+	unsigned long next_update;
  
 	mutex_lock(&data->update_lock);
  
-	if (time_after(jiffies, data->last_updated + HZ) || !data->valid) {
+	next_update = data->last_updated
+	  + msecs_to_jiffies(data->update_interval) + 1;
+
+	if (time_after(jiffies, next_update) || !data->valid) {
 		if (data->config & 0x04) { /* tachometer enabled  */
 			/* order matters for fan1_input */
 			data->fan[0] = i2c_smbus_read_byte_data(client,
...	...	@@ -61,9 +61,9 @@
61	61	(you cannot define your custom PWM/temperature curve), and mode change isn't
62	62	supported either.
63	63
64		-The lm63 driver will not update its values more frequently than every
65		-second; reading them more often will do no harm, but will return 'old'
66		-values.
	64	+The lm63 driver will not update its values more frequently than configured with
	65	+the update_interval sysfs attribute; reading them more often will do no harm,
	66	+but will return 'old' values.
67	67
68	68	The LM64 is effectively an LM63 with GPIO lines. The driver does not
69	69	support these GPIO lines at present.
...	...	@@ -61,6 +61,7 @@
61	61	*/
62	62
63	63	#define LM63_REG_CONFIG1 0x03
	64	+#define LM63_REG_CONVRATE 0x04
64	65	#define LM63_REG_CONFIG2 0xBF
65	66	#define LM63_REG_CONFIG_FAN 0x4A
66	67
...	...	@@ -96,6 +97,11 @@
96	97	#define LM96163_REG_REMOTE_TEMP_U_LSB 0x32
97	98	#define LM96163_REG_CONFIG_ENHANCED 0x45
98	99
	100	+#define LM63_MAX_CONVRATE 9
	101	+
	102	+#define LM63_MAX_CONVRATE_HZ 32
	103	+#define LM96163_MAX_CONVRATE_HZ 26
	104	+
99	105	/*
100	106	* Conversions and various macros
101	107	* For tachometer counts, the LM63 uses 16-bit values.
...	...	@@ -132,6 +138,9 @@
132	138	(val) >= 127000 ? 127 : \
133	139	((val) + 500) / 1000)
134	140
	141	+#define UPDATE_INTERVAL(max, rate) \
	142	+ ((1000 << (LM63_MAX_CONVRATE - (rate))) / (max))
	143	+
135	144	/*
136	145	* Functions declaration
137	146	*/
138	147
...	...	@@ -180,9 +189,12 @@
180	189	struct mutex update_lock;
181	190	char valid; /* zero until following fields are valid */
182	191	unsigned long last_updated; /* in jiffies */
183		- int kind;
	192	+ enum chips kind;
184	193	int temp2_offset;
185	194
	195	+ int update_interval; /* in milliseconds */
	196	+ int max_convrate_hz;
	197	+
186	198	/* registers values */
187	199	u8 config, config_fan;
188	200	u16 fan[2]; /* 0: input
...	...	@@ -449,6 +461,58 @@
449	461	return count;
450	462	}
451	463
	464	+/*
	465	+ * Set conversion rate.
	466	+ * client->update_lock must be held when calling this function.
	467	+ */
	468	+static void lm63_set_convrate(struct i2c_client client, struct lm63_data data,
	469	+ unsigned int interval)
	470	+{
	471	+ int i;
	472	+ unsigned int update_interval;
	473	+
	474	+ /* Shift calculations to avoid rounding errors */
	475	+ interval <<= 6;
	476	+
	477	+ /* find the nearest update rate */
	478	+ update_interval = (1 << (LM63_MAX_CONVRATE + 6)) * 1000
	479	+ / data->max_convrate_hz;
	480	+ for (i = 0; i < LM63_MAX_CONVRATE; i++, update_interval >>= 1)
	481	+ if (interval >= update_interval * 3 / 4)
	482	+ break;
	483	+
	484	+ i2c_smbus_write_byte_data(client, LM63_REG_CONVRATE, i);
	485	+ data->update_interval = UPDATE_INTERVAL(data->max_convrate_hz, i);
	486	+}
	487	+
	488	+static ssize_t show_update_interval(struct device *dev,
	489	+ struct device_attribute attr, char buf)
	490	+{
	491	+ struct lm63_data *data = dev_get_drvdata(dev);
	492	+
	493	+ return sprintf(buf, "%u\n", data->update_interval);
	494	+}
	495	+
	496	+static ssize_t set_update_interval(struct device *dev,
	497	+ struct device_attribute *attr,
	498	+ const char *buf, size_t count)
	499	+{
	500	+ struct i2c_client *client = to_i2c_client(dev);
	501	+ struct lm63_data *data = i2c_get_clientdata(client);
	502	+ unsigned long val;
	503	+ int err;
	504	+
	505	+ err = kstrtoul(buf, 10, &val);
	506	+ if (err)
	507	+ return err;
	508	+
	509	+ mutex_lock(&data->update_lock);
	510	+ lm63_set_convrate(client, data, SENSORS_LIMIT(val, 0, 100000));
	511	+ mutex_unlock(&data->update_lock);
	512	+
	513	+ return count;
	514	+}
	515	+
452	516	static ssize_t show_alarms(struct device dev, struct device_attribute dummy,
453	517	char *buf)
454	518	{
...	...	@@ -499,6 +563,9 @@
499	563	/* Raw alarm file for compatibility */
500	564	static DEVICE_ATTR(alarms, S_IRUGO, show_alarms, NULL);
501	565
	566	+static DEVICE_ATTR(update_interval, S_IRUGO \| S_IWUSR, show_update_interval,
	567	+ set_update_interval);
	568	+
502	569	static struct attribute *lm63_attributes[] = {
503	570	&dev_attr_pwm1.attr,
504	571	&dev_attr_pwm1_enable.attr,
...	...	@@ -517,6 +584,7 @@
517	584	&sensor_dev_attr_temp2_max_alarm.dev_attr.attr,
518	585	&sensor_dev_attr_temp1_max_alarm.dev_attr.attr,
519	586	&dev_attr_alarms.attr,
	587	+ &dev_attr_update_interval.attr,
520	588	NULL
521	589	};
522	590
...	...	@@ -669,6 +737,7 @@
669	737	static void lm63_init_client(struct i2c_client *client)
670	738	{
671	739	struct lm63_data *data = i2c_get_clientdata(client);
	740	+ u8 convrate;
672	741
673	742	data->config = i2c_smbus_read_byte_data(client, LM63_REG_CONFIG1);
674	743	data->config_fan = i2c_smbus_read_byte_data(client,
...	...	@@ -687,6 +756,21 @@
687	756	if (data->pwm1_freq == 0)
688	757	data->pwm1_freq = 1;
689	758
	759	+ switch (data->kind) {
	760	+ case lm63:
	761	+ case lm64:
	762	+ data->max_convrate_hz = LM63_MAX_CONVRATE_HZ;
	763	+ break;
	764	+ case lm96163:
	765	+ data->max_convrate_hz = LM96163_MAX_CONVRATE_HZ;
	766	+ break;
	767	+ }
	768	+ convrate = i2c_smbus_read_byte_data(client, LM63_REG_CONVRATE);
	769	+ if (unlikely(convrate > LM63_MAX_CONVRATE))
	770	+ convrate = LM63_MAX_CONVRATE;
	771	+ data->update_interval = UPDATE_INTERVAL(data->max_convrate_hz,
	772	+ convrate);
	773	+
690	774	/*
691	775	* For LM96163, check if high resolution PWM
692	776	* and unsigned temperature format is enabled.
693	777
...	...	@@ -730,10 +814,14 @@
730	814	{
731	815	struct i2c_client *client = to_i2c_client(dev);
732	816	struct lm63_data *data = i2c_get_clientdata(client);
	817	+ unsigned long next_update;
733	818
734	819	mutex_lock(&data->update_lock);
735	820
736		- if (time_after(jiffies, data->last_updated + HZ) \|\| !data->valid) {
	821	+ next_update = data->last_updated
	822	+ + msecs_to_jiffies(data->update_interval) + 1;
	823	+
	824	+ if (time_after(jiffies, next_update) \|\| !data->valid) {
737	825	if (data->config & 0x04) { /* tachometer enabled */
738	826	/* order matters for fan1_input */
739	827	data->fan[0] = i2c_smbus_read_byte_data(client,