From 04738b2b2f37c13bbe37b7695fec6c1c60d79c7a Mon Sep 17 00:00:00 2001 From: Guenter Roeck Date: Mon, 16 Jan 2012 22:51:46 +0100 Subject: 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 Signed-off-by: Jean Delvare --- drivers/hwmon/lm63.c | 92 ++++++++++++++++++++++++++++++++++++++++++++++++++-- 1 file changed, 90 insertions(+), 2 deletions(-) (limited to 'drivers') diff --git a/drivers/hwmon/lm63.c b/drivers/hwmon/lm63.c index a9e6212ed54..5f6da52a721 100644 --- a/drivers/hwmon/lm63.c +++ b/drivers/hwmon/lm63.c @@ -61,6 +61,7 @@ static const unsigned short normal_i2c[] = { 0x18, 0x4c, 0x4e, I2C_CLIENT_END }; */ #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 @@ static const unsigned short normal_i2c[] = { 0x18, 0x4c, 0x4e, I2C_CLIENT_END }; #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 @@ static const unsigned short normal_i2c[] = { 0x18, 0x4c, 0x4e, I2C_CLIENT_END }; (val) >= 127000 ? 127 : \ ((val) + 500) / 1000) +#define UPDATE_INTERVAL(max, rate) \ + ((1000 << (LM63_MAX_CONVRATE - (rate))) / (max)) + /* * Functions declaration */ @@ -180,9 +189,12 @@ struct lm63_data { 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 @@ static ssize_t set_temp2_crit_hyst(struct device *dev, 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 @@ static SENSOR_DEVICE_ATTR(temp1_max_alarm, S_IRUGO, show_alarm, NULL, 6); /* 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 @@ static struct attribute *lm63_attributes[] = { &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 @@ exit: 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 @@ static void lm63_init_client(struct i2c_client *client) 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 @@ static struct lm63_data *lm63_update_device(struct device *dev) { 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, -- cgit v1.2.3