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Diffstat (limited to 'drivers/hwmon/abx500.c')
-rw-r--r--drivers/hwmon/abx500.c487
1 files changed, 487 insertions, 0 deletions
diff --git a/drivers/hwmon/abx500.c b/drivers/hwmon/abx500.c
new file mode 100644
index 000000000..50e67cdd8
--- /dev/null
+++ b/drivers/hwmon/abx500.c
@@ -0,0 +1,487 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Copyright (C) ST-Ericsson 2010 - 2013
+ * Author: Martin Persson <martin.persson@stericsson.com>
+ * Hongbo Zhang <hongbo.zhang@linaro.org>
+ *
+ * ABX500 does not provide auto ADC, so to monitor the required temperatures,
+ * a periodic work is used. It is more important to not wake up the CPU than
+ * to perform this job, hence the use of a deferred delay.
+ *
+ * A deferred delay for thermal monitor is considered safe because:
+ * If the chip gets too hot during a sleep state it's most likely due to
+ * external factors, such as the surrounding temperature. I.e. no SW decisions
+ * will make any difference.
+ */
+
+#include <linux/err.h>
+#include <linux/hwmon.h>
+#include <linux/hwmon-sysfs.h>
+#include <linux/interrupt.h>
+#include <linux/jiffies.h>
+#include <linux/module.h>
+#include <linux/mutex.h>
+#include <linux/of.h>
+#include <linux/platform_device.h>
+#include <linux/pm.h>
+#include <linux/slab.h>
+#include <linux/sysfs.h>
+#include <linux/workqueue.h>
+#include "abx500.h"
+
+#define DEFAULT_MONITOR_DELAY HZ
+#define DEFAULT_MAX_TEMP 130
+
+static inline void schedule_monitor(struct abx500_temp *data)
+{
+ data->work_active = true;
+ schedule_delayed_work(&data->work, DEFAULT_MONITOR_DELAY);
+}
+
+static void threshold_updated(struct abx500_temp *data)
+{
+ int i;
+ for (i = 0; i < data->monitored_sensors; i++)
+ if (data->max[i] != 0 || data->min[i] != 0) {
+ schedule_monitor(data);
+ return;
+ }
+
+ dev_dbg(&data->pdev->dev, "No active thresholds.\n");
+ cancel_delayed_work_sync(&data->work);
+ data->work_active = false;
+}
+
+static void gpadc_monitor(struct work_struct *work)
+{
+ int temp, i, ret;
+ char alarm_node[30];
+ bool updated_min_alarm, updated_max_alarm;
+ struct abx500_temp *data;
+
+ data = container_of(work, struct abx500_temp, work.work);
+ mutex_lock(&data->lock);
+
+ for (i = 0; i < data->monitored_sensors; i++) {
+ /* Thresholds are considered inactive if set to 0 */
+ if (data->max[i] == 0 && data->min[i] == 0)
+ continue;
+
+ if (data->max[i] < data->min[i])
+ continue;
+
+ ret = data->ops.read_sensor(data, data->gpadc_addr[i], &temp);
+ if (ret < 0) {
+ dev_err(&data->pdev->dev, "GPADC read failed\n");
+ continue;
+ }
+
+ updated_min_alarm = false;
+ updated_max_alarm = false;
+
+ if (data->min[i] != 0) {
+ if (temp < data->min[i]) {
+ if (data->min_alarm[i] == false) {
+ data->min_alarm[i] = true;
+ updated_min_alarm = true;
+ }
+ } else {
+ if (data->min_alarm[i] == true) {
+ data->min_alarm[i] = false;
+ updated_min_alarm = true;
+ }
+ }
+ }
+ if (data->max[i] != 0) {
+ if (temp > data->max[i]) {
+ if (data->max_alarm[i] == false) {
+ data->max_alarm[i] = true;
+ updated_max_alarm = true;
+ }
+ } else if (temp < data->max[i] - data->max_hyst[i]) {
+ if (data->max_alarm[i] == true) {
+ data->max_alarm[i] = false;
+ updated_max_alarm = true;
+ }
+ }
+ }
+
+ if (updated_min_alarm) {
+ ret = sprintf(alarm_node, "temp%d_min_alarm", i + 1);
+ sysfs_notify(&data->pdev->dev.kobj, NULL, alarm_node);
+ }
+ if (updated_max_alarm) {
+ ret = sprintf(alarm_node, "temp%d_max_alarm", i + 1);
+ sysfs_notify(&data->pdev->dev.kobj, NULL, alarm_node);
+ }
+ }
+
+ schedule_monitor(data);
+ mutex_unlock(&data->lock);
+}
+
+/* HWMON sysfs interfaces */
+static ssize_t name_show(struct device *dev, struct device_attribute *devattr,
+ char *buf)
+{
+ struct abx500_temp *data = dev_get_drvdata(dev);
+ /* Show chip name */
+ return data->ops.show_name(dev, devattr, buf);
+}
+
+static ssize_t label_show(struct device *dev,
+ struct device_attribute *devattr, char *buf)
+{
+ struct abx500_temp *data = dev_get_drvdata(dev);
+ /* Show each sensor label */
+ return data->ops.show_label(dev, devattr, buf);
+}
+
+static ssize_t input_show(struct device *dev,
+ struct device_attribute *devattr, char *buf)
+{
+ int ret, temp;
+ struct abx500_temp *data = dev_get_drvdata(dev);
+ struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
+ u8 gpadc_addr = data->gpadc_addr[attr->index];
+
+ ret = data->ops.read_sensor(data, gpadc_addr, &temp);
+ if (ret < 0)
+ return ret;
+
+ return sprintf(buf, "%d\n", temp);
+}
+
+/* Set functions (RW nodes) */
+static ssize_t min_store(struct device *dev, struct device_attribute *devattr,
+ const char *buf, size_t count)
+{
+ unsigned long val;
+ struct abx500_temp *data = dev_get_drvdata(dev);
+ struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
+ int res = kstrtol(buf, 10, &val);
+ if (res < 0)
+ return res;
+
+ val = clamp_val(val, 0, DEFAULT_MAX_TEMP);
+
+ mutex_lock(&data->lock);
+ data->min[attr->index] = val;
+ threshold_updated(data);
+ mutex_unlock(&data->lock);
+
+ return count;
+}
+
+static ssize_t max_store(struct device *dev, struct device_attribute *devattr,
+ const char *buf, size_t count)
+{
+ unsigned long val;
+ struct abx500_temp *data = dev_get_drvdata(dev);
+ struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
+ int res = kstrtol(buf, 10, &val);
+ if (res < 0)
+ return res;
+
+ val = clamp_val(val, 0, DEFAULT_MAX_TEMP);
+
+ mutex_lock(&data->lock);
+ data->max[attr->index] = val;
+ threshold_updated(data);
+ mutex_unlock(&data->lock);
+
+ return count;
+}
+
+static ssize_t max_hyst_store(struct device *dev,
+ struct device_attribute *devattr,
+ const char *buf, size_t count)
+{
+ unsigned long val;
+ struct abx500_temp *data = dev_get_drvdata(dev);
+ struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
+ int res = kstrtoul(buf, 10, &val);
+ if (res < 0)
+ return res;
+
+ val = clamp_val(val, 0, DEFAULT_MAX_TEMP);
+
+ mutex_lock(&data->lock);
+ data->max_hyst[attr->index] = val;
+ threshold_updated(data);
+ mutex_unlock(&data->lock);
+
+ return count;
+}
+
+/* Show functions (RO nodes) */
+static ssize_t min_show(struct device *dev, struct device_attribute *devattr,
+ char *buf)
+{
+ struct abx500_temp *data = dev_get_drvdata(dev);
+ struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
+
+ return sprintf(buf, "%lu\n", data->min[attr->index]);
+}
+
+static ssize_t max_show(struct device *dev, struct device_attribute *devattr,
+ char *buf)
+{
+ struct abx500_temp *data = dev_get_drvdata(dev);
+ struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
+
+ return sprintf(buf, "%lu\n", data->max[attr->index]);
+}
+
+static ssize_t max_hyst_show(struct device *dev,
+ struct device_attribute *devattr, char *buf)
+{
+ struct abx500_temp *data = dev_get_drvdata(dev);
+ struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
+
+ return sprintf(buf, "%lu\n", data->max_hyst[attr->index]);
+}
+
+static ssize_t min_alarm_show(struct device *dev,
+ struct device_attribute *devattr, char *buf)
+{
+ struct abx500_temp *data = dev_get_drvdata(dev);
+ struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
+
+ return sprintf(buf, "%d\n", data->min_alarm[attr->index]);
+}
+
+static ssize_t max_alarm_show(struct device *dev,
+ struct device_attribute *devattr, char *buf)
+{
+ struct abx500_temp *data = dev_get_drvdata(dev);
+ struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
+
+ return sprintf(buf, "%d\n", data->max_alarm[attr->index]);
+}
+
+static umode_t abx500_attrs_visible(struct kobject *kobj,
+ struct attribute *attr, int n)
+{
+ struct device *dev = container_of(kobj, struct device, kobj);
+ struct abx500_temp *data = dev_get_drvdata(dev);
+
+ if (data->ops.is_visible)
+ return data->ops.is_visible(attr, n);
+
+ return attr->mode;
+}
+
+/* Chip name, required by hwmon */
+static SENSOR_DEVICE_ATTR_RO(name, name, 0);
+
+/* GPADC - SENSOR1 */
+static SENSOR_DEVICE_ATTR_RO(temp1_label, label, 0);
+static SENSOR_DEVICE_ATTR_RO(temp1_input, input, 0);
+static SENSOR_DEVICE_ATTR_RW(temp1_min, min, 0);
+static SENSOR_DEVICE_ATTR_RW(temp1_max, max, 0);
+static SENSOR_DEVICE_ATTR_RW(temp1_max_hyst, max_hyst, 0);
+static SENSOR_DEVICE_ATTR_RO(temp1_min_alarm, min_alarm, 0);
+static SENSOR_DEVICE_ATTR_RO(temp1_max_alarm, max_alarm, 0);
+
+/* GPADC - SENSOR2 */
+static SENSOR_DEVICE_ATTR_RO(temp2_label, label, 1);
+static SENSOR_DEVICE_ATTR_RO(temp2_input, input, 1);
+static SENSOR_DEVICE_ATTR_RW(temp2_min, min, 1);
+static SENSOR_DEVICE_ATTR_RW(temp2_max, max, 1);
+static SENSOR_DEVICE_ATTR_RW(temp2_max_hyst, max_hyst, 1);
+static SENSOR_DEVICE_ATTR_RO(temp2_min_alarm, min_alarm, 1);
+static SENSOR_DEVICE_ATTR_RO(temp2_max_alarm, max_alarm, 1);
+
+/* GPADC - SENSOR3 */
+static SENSOR_DEVICE_ATTR_RO(temp3_label, label, 2);
+static SENSOR_DEVICE_ATTR_RO(temp3_input, input, 2);
+static SENSOR_DEVICE_ATTR_RW(temp3_min, min, 2);
+static SENSOR_DEVICE_ATTR_RW(temp3_max, max, 2);
+static SENSOR_DEVICE_ATTR_RW(temp3_max_hyst, max_hyst, 2);
+static SENSOR_DEVICE_ATTR_RO(temp3_min_alarm, min_alarm, 2);
+static SENSOR_DEVICE_ATTR_RO(temp3_max_alarm, max_alarm, 2);
+
+/* GPADC - SENSOR4 */
+static SENSOR_DEVICE_ATTR_RO(temp4_label, label, 3);
+static SENSOR_DEVICE_ATTR_RO(temp4_input, input, 3);
+static SENSOR_DEVICE_ATTR_RW(temp4_min, min, 3);
+static SENSOR_DEVICE_ATTR_RW(temp4_max, max, 3);
+static SENSOR_DEVICE_ATTR_RW(temp4_max_hyst, max_hyst, 3);
+static SENSOR_DEVICE_ATTR_RO(temp4_min_alarm, min_alarm, 3);
+static SENSOR_DEVICE_ATTR_RO(temp4_max_alarm, max_alarm, 3);
+
+static struct attribute *abx500_temp_attributes[] = {
+ &sensor_dev_attr_name.dev_attr.attr,
+
+ &sensor_dev_attr_temp1_label.dev_attr.attr,
+ &sensor_dev_attr_temp1_input.dev_attr.attr,
+ &sensor_dev_attr_temp1_min.dev_attr.attr,
+ &sensor_dev_attr_temp1_max.dev_attr.attr,
+ &sensor_dev_attr_temp1_max_hyst.dev_attr.attr,
+ &sensor_dev_attr_temp1_min_alarm.dev_attr.attr,
+ &sensor_dev_attr_temp1_max_alarm.dev_attr.attr,
+
+ &sensor_dev_attr_temp2_label.dev_attr.attr,
+ &sensor_dev_attr_temp2_input.dev_attr.attr,
+ &sensor_dev_attr_temp2_min.dev_attr.attr,
+ &sensor_dev_attr_temp2_max.dev_attr.attr,
+ &sensor_dev_attr_temp2_max_hyst.dev_attr.attr,
+ &sensor_dev_attr_temp2_min_alarm.dev_attr.attr,
+ &sensor_dev_attr_temp2_max_alarm.dev_attr.attr,
+
+ &sensor_dev_attr_temp3_label.dev_attr.attr,
+ &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_max_hyst.dev_attr.attr,
+ &sensor_dev_attr_temp3_min_alarm.dev_attr.attr,
+ &sensor_dev_attr_temp3_max_alarm.dev_attr.attr,
+
+ &sensor_dev_attr_temp4_label.dev_attr.attr,
+ &sensor_dev_attr_temp4_input.dev_attr.attr,
+ &sensor_dev_attr_temp4_min.dev_attr.attr,
+ &sensor_dev_attr_temp4_max.dev_attr.attr,
+ &sensor_dev_attr_temp4_max_hyst.dev_attr.attr,
+ &sensor_dev_attr_temp4_min_alarm.dev_attr.attr,
+ &sensor_dev_attr_temp4_max_alarm.dev_attr.attr,
+ NULL
+};
+
+static const struct attribute_group abx500_temp_group = {
+ .attrs = abx500_temp_attributes,
+ .is_visible = abx500_attrs_visible,
+};
+
+static irqreturn_t abx500_temp_irq_handler(int irq, void *irq_data)
+{
+ struct platform_device *pdev = irq_data;
+ struct abx500_temp *data = platform_get_drvdata(pdev);
+
+ data->ops.irq_handler(irq, data);
+ return IRQ_HANDLED;
+}
+
+static int setup_irqs(struct platform_device *pdev)
+{
+ int ret;
+ int irq = platform_get_irq_byname(pdev, "ABX500_TEMP_WARM");
+
+ if (irq < 0) {
+ dev_err(&pdev->dev, "Get irq by name failed\n");
+ return irq;
+ }
+
+ ret = devm_request_threaded_irq(&pdev->dev, irq, NULL,
+ abx500_temp_irq_handler, 0, "abx500-temp", pdev);
+ if (ret < 0)
+ dev_err(&pdev->dev, "Request threaded irq failed (%d)\n", ret);
+
+ return ret;
+}
+
+static int abx500_temp_probe(struct platform_device *pdev)
+{
+ struct abx500_temp *data;
+ int err;
+
+ data = devm_kzalloc(&pdev->dev, sizeof(*data), GFP_KERNEL);
+ if (!data)
+ return -ENOMEM;
+
+ data->pdev = pdev;
+ mutex_init(&data->lock);
+
+ /* Chip specific initialization */
+ err = abx500_hwmon_init(data);
+ if (err < 0 || !data->ops.read_sensor || !data->ops.show_name ||
+ !data->ops.show_label)
+ return err;
+
+ INIT_DEFERRABLE_WORK(&data->work, gpadc_monitor);
+
+ platform_set_drvdata(pdev, data);
+
+ err = sysfs_create_group(&pdev->dev.kobj, &abx500_temp_group);
+ if (err < 0) {
+ dev_err(&pdev->dev, "Create sysfs group failed (%d)\n", err);
+ return err;
+ }
+
+ data->hwmon_dev = hwmon_device_register(&pdev->dev);
+ if (IS_ERR(data->hwmon_dev)) {
+ err = PTR_ERR(data->hwmon_dev);
+ dev_err(&pdev->dev, "Class registration failed (%d)\n", err);
+ goto exit_sysfs_group;
+ }
+
+ if (data->ops.irq_handler) {
+ err = setup_irqs(pdev);
+ if (err < 0)
+ goto exit_hwmon_reg;
+ }
+ return 0;
+
+exit_hwmon_reg:
+ hwmon_device_unregister(data->hwmon_dev);
+exit_sysfs_group:
+ sysfs_remove_group(&pdev->dev.kobj, &abx500_temp_group);
+ return err;
+}
+
+static int abx500_temp_remove(struct platform_device *pdev)
+{
+ struct abx500_temp *data = platform_get_drvdata(pdev);
+
+ cancel_delayed_work_sync(&data->work);
+ hwmon_device_unregister(data->hwmon_dev);
+ sysfs_remove_group(&pdev->dev.kobj, &abx500_temp_group);
+
+ return 0;
+}
+
+static int abx500_temp_suspend(struct platform_device *pdev,
+ pm_message_t state)
+{
+ struct abx500_temp *data = platform_get_drvdata(pdev);
+
+ if (data->work_active)
+ cancel_delayed_work_sync(&data->work);
+
+ return 0;
+}
+
+static int abx500_temp_resume(struct platform_device *pdev)
+{
+ struct abx500_temp *data = platform_get_drvdata(pdev);
+
+ if (data->work_active)
+ schedule_monitor(data);
+
+ return 0;
+}
+
+#ifdef CONFIG_OF
+static const struct of_device_id abx500_temp_match[] = {
+ { .compatible = "stericsson,abx500-temp" },
+ {},
+};
+MODULE_DEVICE_TABLE(of, abx500_temp_match);
+#endif
+
+static struct platform_driver abx500_temp_driver = {
+ .driver = {
+ .name = "abx500-temp",
+ .of_match_table = of_match_ptr(abx500_temp_match),
+ },
+ .suspend = abx500_temp_suspend,
+ .resume = abx500_temp_resume,
+ .probe = abx500_temp_probe,
+ .remove = abx500_temp_remove,
+};
+
+module_platform_driver(abx500_temp_driver);
+
+MODULE_AUTHOR("Martin Persson <martin.persson@stericsson.com>");
+MODULE_DESCRIPTION("ABX500 temperature driver");
+MODULE_LICENSE("GPL");