diff options
Diffstat (limited to 'drivers/hwmon/ab5500.c')
| -rw-r--r-- | drivers/hwmon/ab5500.c | 212 |
1 files changed, 212 insertions, 0 deletions
diff --git a/drivers/hwmon/ab5500.c b/drivers/hwmon/ab5500.c new file mode 100644 index 00000000000..cafadeba51c --- /dev/null +++ b/drivers/hwmon/ab5500.c @@ -0,0 +1,212 @@ +/* + * Copyright (C) ST-Ericsson SA 2010 + * Author: Martin Persson <martin.persson@stericsson.com> for + * ST-Ericsson. + * License terms: GNU Gereral Public License (GPL) version 2 + * + * Note: + * + * If/when the AB5500 thermal warning temperature is reached (threshold + * 125C cannot be changed by SW), an interrupt is set and the driver + * notifies user space via a sysfs event. If a shut down is not + * triggered by user space and temperature reaches beyond critical + * limit(130C) pm_power off is called. + * + * If/when AB5500 thermal shutdown temperature is reached a hardware + * shutdown of the AB5500 will occur. + */ + +#include <linux/slab.h> +#include <linux/err.h> +#include <linux/hwmon.h> +#include <linux/sysfs.h> +#include <linux/hwmon-sysfs.h> +#include <linux/platform_device.h> +#include <linux/mfd/abx500/ab5500-gpadc.h> +#include <linux/mfd/abx500/ab5500-bm.h> +#include "abx500.h" +#include <asm/mach-types.h> + +/* AB5500 driver monitors GPADC - XTAL_TEMP, PCB_TEMP, + * BTEMP_BALL, BAT_CTRL and DIE_TEMP + */ +#define NUM_MONITORED_SENSORS 5 + +#define SHUTDOWN_AUTO_MIN_LIMIT -25 +#define SHUTDOWN_AUTO_MAX_LIMIT 130 + +static int ab5500_output_convert(int val, u8 sensor) +{ + int res = val; + /* GPADC returns die temperature in Celsius + * convert it to millidegree celsius + */ + if (sensor == DIE_TEMP) + res = val * 1000; + + return res; +} + +static int ab5500_read_sensor(struct abx500_temp *data, u8 sensor) +{ + int val; + /* + * Special treatment for BAT_CTRL node, since this + * temperature measurement is more complex than just + * an ADC readout + */ + if (sensor == BAT_CTRL) + val = ab5500_btemp_get_batctrl_temp(data->ab5500_btemp); + else + val = ab5500_gpadc_convert(data->ab5500_gpadc, sensor); + + if (val < 0) + return val; + else + return ab5500_output_convert(val, sensor); +} + +static ssize_t ab5500_show_name(struct device *dev, + struct device_attribute *devattr, + char *buf) +{ + return sprintf(buf, "ab5500\n"); +} + +static ssize_t ab5500_show_label(struct device *dev, + struct device_attribute *devattr, + char *buf) +{ + char *name; + struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr); + int index = attr->index; + + /* + * Make sure these labels correspond to the attribute indexes + * used when calling SENSOR_DEVICE_ATRR. + * Temperature sensors outside ab8500 (read via GPADC) are marked + * with prefix ext_ + */ + switch (index) { + case 1: + name = "xtal_temp"; + break; + case 2: + name = "pcb_temp"; + break; + case 3: + name = "bat_temp"; + break; + case 4: + name = "bat_ctrl"; + break; + case 5: + name = "ab5500"; + break; + default: + return -EINVAL; + } + return sprintf(buf, "%s\n", name); +} + +static int temp_shutdown_trig(int mux) +{ + pm_power_off(); + return 0; +} + +static int ab5500_temp_shutdown_auto(struct abx500_temp *data) +{ + int ret; + struct adc_auto_input *auto_ip; + + auto_ip = kzalloc(sizeof(struct adc_auto_input), GFP_KERNEL); + if (!auto_ip) { + dev_err(&data->pdev->dev, "failed to allocate memory\n"); + return -ENOMEM; + } + + auto_ip->mux = DIE_TEMP; + auto_ip->freq = MS500; + /* + * As per product specification, voltage decreases as + * temperature increases. Hence the min and max values + * should be passed in reverse order. + */ + auto_ip->min = SHUTDOWN_AUTO_MAX_LIMIT; + auto_ip->max = SHUTDOWN_AUTO_MIN_LIMIT; + auto_ip->auto_adc_callback = temp_shutdown_trig; + data->gpadc_auto = auto_ip; + ret = ab5500_gpadc_convert_auto(data->ab5500_gpadc, + data->gpadc_auto); + if (ret < 0) + kfree(auto_ip); + + return ret; +} + +static int ab5500_is_visible(struct attribute *attr, int n) +{ + return attr->mode; +} + +static int ab5500_temp_irq_handler(int irq, struct abx500_temp *data) +{ + /* + * Make sure the magic numbers below corresponds to the node + * used for AB5500 thermal warning from HW. + */ + mutex_lock(&data->lock); + data->crit_alarm[4] = 1; + mutex_unlock(&data->lock); + sysfs_notify(&data->pdev->dev.kobj, NULL, "temp5_crit_alarm"); + dev_info(&data->pdev->dev, "ABX500 thermal warning," + " power off system now!\n"); + return 0; +} + +int __init ab5500_hwmon_init(struct abx500_temp *data) +{ + int err; + + data->ab5500_gpadc = ab5500_gpadc_get("ab5500-adc.0"); + if (IS_ERR(data->ab5500_gpadc)) + return PTR_ERR(data->ab5500_gpadc); + + data->ab5500_btemp = ab5500_btemp_get(); + if (IS_ERR(data->ab5500_btemp)) + return PTR_ERR(data->ab5500_btemp); + + err = ab5500_temp_shutdown_auto(data); + if (err < 0) { + dev_err(&data->pdev->dev, "Failed to register" + " auto trigger(%d)\n", err); + return err; + } + + /* + * Setup HW defined data. + * + * Reference hardware (HREF): + * + * XTAL_TEMP, PCB_TEMP, BTEMP_BALL refer to millivolts and + * BAT_CTRL and DIE_TEMP refer to millidegrees + * + * Make sure indexes correspond to the attribute indexes + * used when calling SENSOR_DEVICE_ATRR + */ + data->gpadc_addr[0] = XTAL_TEMP; + data->gpadc_addr[1] = PCB_TEMP; + data->gpadc_addr[2] = BTEMP_BALL; + data->gpadc_addr[3] = BAT_CTRL; + data->gpadc_addr[4] = DIE_TEMP; + data->monitored_sensors = NUM_MONITORED_SENSORS; + + data->ops.read_sensor = ab5500_read_sensor; + data->ops.irq_handler = ab5500_temp_irq_handler; + data->ops.show_name = ab5500_show_name; + data->ops.show_label = ab5500_show_label; + data->ops.is_visible = ab5500_is_visible; + + return 0; +} |