From: Christian Engelmayer <christian.engelmayer at frequentis.com> Exported the alarm stati provided by the MAX6650/MAX6651 fan-speed regulator and monitor chips via sysfs. Signed-off-by: Christian Engelmayer <christian.engelmayer at frequentis.com> --- Tested with the MAX6651 chip. This obsoletes the previously proposed patch 'support for the max6650 GPIO and alarm features' after discussion on sane gpio handling. Revised after remarks by Hans de Goede. Changed the alarm attributes to sensor device attributes thus eliminating the need for pointer comparison in show function get_alarm(). Left the alarm behaviour unchanged. In case the sysfs interface does not prefer 'real time' over 'latched' alarms I prefer to keep the style used by the device. Incorporated additional remarks by Hans de Goede. Changed a temporary variable from 'u8' to 'int'. Changed the order of alarms within the code from MSB first to LSB first as occuring within the registers. Incorporated additional remarks by Jean Delvare. Using attr->index for directly passing alarm masks. Resending the patch as it was previously corrupted by the mail client. --- linux-2.6.29.4-vanilla/drivers/hwmon/max6650.c 2009-05-30 23:58:59.000000000 +0200 +++ linux-2.6.29.4/drivers/hwmon/max6650.c 2009-05-31 00:01:47.000000000 +0200 @@ -12,7 +12,7 @@ * also work with the MAX6651. It does not distinguish max6650 and max6651 * chips. * - * Tha datasheet was last seen at: + * The datasheet was last seen at: * * http://pdfserv.maxim-ic.com/en/ds/MAX6650-MAX6651.pdf * @@ -98,6 +98,17 @@ I2C_CLIENT_INSMOD_1(max6650); #define MAX6650_CFG_MODE_OPEN_LOOP 0x30 #define MAX6650_COUNT_MASK 0x03 +/* + * Alarm status register bits + */ + +#define MAX6650_ALRM_MAX 0x01 +#define MAX6650_ALRM_MIN 0x02 +#define MAX6650_ALRM_TACH 0x04 +#define MAX6650_ALRM_GPIO1 0x08 +#define MAX6650_ALRM_GPIO2 0x10 +#define MAX6650_ALRM_MASK 0x1F + /* Minimum and maximum values of the FAN-RPM */ #define FAN_RPM_MIN 240 #define FAN_RPM_MAX 30000 @@ -151,6 +162,7 @@ struct max6650_data u8 tach[4]; u8 count; u8 dac; + u8 alarm; }; static ssize_t get_fan(struct device *dev, struct device_attribute *devattr, @@ -418,6 +430,33 @@ static ssize_t set_div(struct device *de return count; } +/* + * Get alarm stati: + * Possible values: + * 0 = no alarm + * 1 = alarm + */ + +static ssize_t get_alarm(struct device *dev, struct device_attribute *devattr, + char *buf) +{ + struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr); + struct max6650_data *data = max6650_update_device(dev); + struct i2c_client *client = to_i2c_client(dev); + int alarm = 0; + + if (data->alarm & attr->index) { + mutex_lock(&data->update_lock); + alarm = 1; + data->alarm &= ~attr->index; + data->alarm |= i2c_smbus_read_byte_data(client, + MAX6650_REG_ALARM); + mutex_unlock(&data->update_lock); + } + + return sprintf(buf, "%d\n", alarm); +} + static SENSOR_DEVICE_ATTR(fan1_input, S_IRUGO, get_fan, NULL, 0); static SENSOR_DEVICE_ATTR(fan2_input, S_IRUGO, get_fan, NULL, 1); static SENSOR_DEVICE_ATTR(fan3_input, S_IRUGO, get_fan, NULL, 2); @@ -426,7 +465,47 @@ static DEVICE_ATTR(fan1_target, S_IWUSR static DEVICE_ATTR(fan1_div, S_IWUSR | S_IRUGO, get_div, set_div); static DEVICE_ATTR(pwm1_enable, S_IWUSR | S_IRUGO, get_enable, set_enable); static DEVICE_ATTR(pwm1, S_IWUSR | S_IRUGO, get_pwm, set_pwm); +static SENSOR_DEVICE_ATTR(fan1_max_alarm, S_IRUGO, get_alarm, NULL, + MAX6650_ALRM_MAX); +static SENSOR_DEVICE_ATTR(fan1_min_alarm, S_IRUGO, get_alarm, NULL, + MAX6650_ALRM_MIN); +static SENSOR_DEVICE_ATTR(fan1_fault, S_IRUGO, get_alarm, NULL, + MAX6650_ALRM_TACH); +static SENSOR_DEVICE_ATTR(gpio1_alarm, S_IRUGO, get_alarm, NULL, + MAX6650_ALRM_GPIO1); +static SENSOR_DEVICE_ATTR(gpio2_alarm, S_IRUGO, get_alarm, NULL, + MAX6650_ALRM_GPIO2); + +static mode_t max6650_attrs_visible(struct kobject *kobj, struct attribute *a, + int n) +{ + struct device *dev = container_of(kobj, struct device, kobj); + struct i2c_client *client = to_i2c_client(dev); + u8 alarm_en = i2c_smbus_read_byte_data(client, MAX6650_REG_ALARM_EN); + /* + * Hide the alarms that have not been enabled by the firmware + */ + + if (a == &sensor_dev_attr_fan1_max_alarm.dev_attr.attr) { + if (!(alarm_en & MAX6650_ALRM_MAX)) + return 0; + } else if (a == &sensor_dev_attr_fan1_min_alarm.dev_attr.attr) { + if (!(alarm_en & MAX6650_ALRM_MIN)) + return 0; + } else if (a == &sensor_dev_attr_fan1_fault.dev_attr.attr) { + if (!(alarm_en & MAX6650_ALRM_TACH)) + return 0; + } else if (a == &sensor_dev_attr_gpio1_alarm.dev_attr.attr) { + if (!(alarm_en & MAX6650_ALRM_GPIO1)) + return 0; + } else if (a == &sensor_dev_attr_gpio2_alarm.dev_attr.attr) { + if (!(alarm_en & MAX6650_ALRM_GPIO2)) + return 0; + } + + return a->mode; +} static struct attribute *max6650_attrs[] = { &sensor_dev_attr_fan1_input.dev_attr.attr, @@ -437,11 +516,17 @@ static struct attribute *max6650_attrs[] &dev_attr_fan1_div.attr, &dev_attr_pwm1_enable.attr, &dev_attr_pwm1.attr, + &sensor_dev_attr_fan1_max_alarm.dev_attr.attr, + &sensor_dev_attr_fan1_min_alarm.dev_attr.attr, + &sensor_dev_attr_fan1_fault.dev_attr.attr, + &sensor_dev_attr_gpio1_alarm.dev_attr.attr, + &sensor_dev_attr_gpio2_alarm.dev_attr.attr, NULL }; static struct attribute_group max6650_attr_grp = { .attrs = max6650_attrs, + .is_visible = max6650_attrs_visible, }; /* @@ -659,6 +744,12 @@ static struct max6650_data *max6650_upda MAX6650_REG_COUNT); data->dac = i2c_smbus_read_byte_data(client, MAX6650_REG_DAC); + /* Alarms are cleared on read in case the condition that + * caused the alarm is removed. Keep the value latched here + * for providing the register through different alarm files. */ + data->alarm |= i2c_smbus_read_byte_data(client, + MAX6650_REG_ALARM); + data->last_updated = jiffies; data->valid = 1; }
