[BATTERY] Universal power supply class (was: battery class)
This class is result of "external power" and "battery" classes merge,
as suggested by David Woodhouse. He also implemented uevent support.
Here how userspace seeing it now:
# ls /sys/class/power\ supply/
ac main-battery usb
# cat /sys/class/power\ supply/ac/type
AC
# cat /sys/class/power\ supply/usb/type
USB
# cat /sys/class/power\ supply/main-battery/type
Battery
# cat /sys/class/power\ supply/ac/online
1
# cat /sys/class/power\ supply/usb/online
0
# cat /sys/class/power\ supply/main-battery/status
Charging
# cat /sys/class/leds/h5400\:red-left/trigger
none h5400-radio timer hwtimer ac-online usb-online
main-battery-charging-or-full [main-battery-charging]
main-battery-full
Signed-off-by: Anton Vorontsov <cbou@mail.ru>
Signed-off-by: David Woodhouse <dwmw2@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
diff --git a/drivers/power/power_supply_sysfs.c b/drivers/power/power_supply_sysfs.c
new file mode 100644
index 0000000..c07d425
--- /dev/null
+++ b/drivers/power/power_supply_sysfs.c
@@ -0,0 +1,299 @@
+/*
+ * Sysfs interface for the universal power supply monitor class
+ *
+ * Copyright © 2007 David Woodhouse <dwmw2@infradead.org>
+ * Copyright © 2007 Anton Vorontsov <cbou@mail.ru>
+ * Copyright © 2004 Szabolcs Gyurko
+ * Copyright © 2003 Ian Molton <spyro@f2s.com>
+ *
+ * Modified: 2004, Oct Szabolcs Gyurko
+ *
+ * You may use this code as per GPL version 2
+ */
+
+#include <linux/ctype.h>
+#include <linux/power_supply.h>
+
+/*
+ * This is because the name "current" breaks the device attr macro.
+ * The "current" word resolves to "(get_current())" so instead of
+ * "current" "(get_current())" appears in the sysfs.
+ *
+ * The source of this definition is the device.h which calls __ATTR
+ * macro in sysfs.h which calls the __stringify macro.
+ *
+ * Only modification that the name is not tried to be resolved
+ * (as a macro let's say).
+ */
+
+#define POWER_SUPPLY_ATTR(_name) \
+{ \
+ .attr = { .name = #_name, .mode = 0444, .owner = THIS_MODULE }, \
+ .show = power_supply_show_property, \
+ .store = NULL, \
+}
+
+static struct device_attribute power_supply_attrs[];
+
+static ssize_t power_supply_show_property(struct device *dev,
+ struct device_attribute *attr,
+ char *buf) {
+ static char *status_text[] = {
+ "Unknown", "Charging", "Discharging", "Not charging", "Full"
+ };
+ static char *health_text[] = {
+ "Unknown", "Good", "Overheat", "Dead", "Over voltage",
+ "Unspecified failure"
+ };
+ static char *technology_text[] = {
+ "Unknown", "NiMH", "Li-ion", "Li-poly", "LiFe", "NiCd"
+ };
+ static char *capacity_level_text[] = {
+ "Unknown", "Critical", "Low", "Normal", "High", "Full"
+ };
+ ssize_t ret;
+ struct power_supply *psy = dev_get_drvdata(dev);
+ const ptrdiff_t off = attr - power_supply_attrs;
+ union power_supply_propval value;
+
+ ret = psy->get_property(psy, off, &value);
+
+ if (ret < 0) {
+ if (ret != -ENODEV)
+ dev_err(dev, "driver failed to report `%s' property\n",
+ attr->attr.name);
+ return ret;
+ }
+
+ if (off == POWER_SUPPLY_PROP_STATUS)
+ return sprintf(buf, "%s\n", status_text[value.intval]);
+ else if (off == POWER_SUPPLY_PROP_HEALTH)
+ return sprintf(buf, "%s\n", health_text[value.intval]);
+ else if (off == POWER_SUPPLY_PROP_TECHNOLOGY)
+ return sprintf(buf, "%s\n", technology_text[value.intval]);
+ else if (off == POWER_SUPPLY_PROP_CAPACITY_LEVEL)
+ return sprintf(buf, "%s\n",
+ capacity_level_text[value.intval]);
+ else if (off >= POWER_SUPPLY_PROP_MODEL_NAME)
+ return sprintf(buf, "%s\n", value.strval);
+
+ return sprintf(buf, "%d\n", value.intval);
+}
+
+/* Must be in the same order as POWER_SUPPLY_PROP_* */
+static struct device_attribute power_supply_attrs[] = {
+ /* Properties of type `int' */
+ POWER_SUPPLY_ATTR(status),
+ POWER_SUPPLY_ATTR(health),
+ POWER_SUPPLY_ATTR(present),
+ POWER_SUPPLY_ATTR(online),
+ POWER_SUPPLY_ATTR(technology),
+ POWER_SUPPLY_ATTR(voltage_max_design),
+ POWER_SUPPLY_ATTR(voltage_min_design),
+ POWER_SUPPLY_ATTR(voltage_now),
+ POWER_SUPPLY_ATTR(voltage_avg),
+ POWER_SUPPLY_ATTR(current_now),
+ POWER_SUPPLY_ATTR(current_avg),
+ POWER_SUPPLY_ATTR(charge_full_design),
+ POWER_SUPPLY_ATTR(charge_empty_design),
+ POWER_SUPPLY_ATTR(charge_full),
+ POWER_SUPPLY_ATTR(charge_empty),
+ POWER_SUPPLY_ATTR(charge_now),
+ POWER_SUPPLY_ATTR(charge_avg),
+ POWER_SUPPLY_ATTR(energy_full_design),
+ POWER_SUPPLY_ATTR(energy_empty_design),
+ POWER_SUPPLY_ATTR(energy_full),
+ POWER_SUPPLY_ATTR(energy_empty),
+ POWER_SUPPLY_ATTR(energy_now),
+ POWER_SUPPLY_ATTR(energy_avg),
+ POWER_SUPPLY_ATTR(capacity),
+ POWER_SUPPLY_ATTR(capacity_level),
+ POWER_SUPPLY_ATTR(temp),
+ POWER_SUPPLY_ATTR(temp_ambient),
+ POWER_SUPPLY_ATTR(time_to_empty_now),
+ POWER_SUPPLY_ATTR(time_to_empty_avg),
+ POWER_SUPPLY_ATTR(time_to_full_now),
+ POWER_SUPPLY_ATTR(time_to_full_avg),
+ /* Properties of type `const char *' */
+ POWER_SUPPLY_ATTR(model_name),
+ POWER_SUPPLY_ATTR(manufacturer),
+};
+
+static ssize_t power_supply_show_static_attrs(struct device *dev,
+ struct device_attribute *attr,
+ char *buf) {
+ static char *type_text[] = { "Battery", "UPS", "Mains", "USB" };
+ struct power_supply *psy = dev_get_drvdata(dev);
+
+ return sprintf(buf, "%s\n", type_text[psy->type]);
+}
+
+static struct device_attribute power_supply_static_attrs[] = {
+ __ATTR(type, 0444, power_supply_show_static_attrs, NULL),
+};
+
+int power_supply_create_attrs(struct power_supply *psy)
+{
+ int rc = 0;
+ int i, j;
+
+ for (i = 0; i < ARRAY_SIZE(power_supply_static_attrs); i++) {
+ rc = device_create_file(psy->dev,
+ &power_supply_static_attrs[i]);
+ if (rc)
+ goto statics_failed;
+ }
+
+ for (j = 0; j < psy->num_properties; j++) {
+ rc = device_create_file(psy->dev,
+ &power_supply_attrs[psy->properties[j]]);
+ if (rc)
+ goto dynamics_failed;
+ }
+
+ goto succeed;
+
+dynamics_failed:
+ while (j--)
+ device_remove_file(psy->dev,
+ &power_supply_attrs[psy->properties[j]]);
+statics_failed:
+ while (i--)
+ device_remove_file(psy->dev,
+ &power_supply_static_attrs[psy->properties[i]]);
+succeed:
+ return rc;
+}
+
+void power_supply_remove_attrs(struct power_supply *psy)
+{
+ int i;
+
+ for (i = 0; i < ARRAY_SIZE(power_supply_static_attrs); i++)
+ device_remove_file(psy->dev,
+ &power_supply_static_attrs[i]);
+
+ for (i = 0; i < psy->num_properties; i++)
+ device_remove_file(psy->dev,
+ &power_supply_attrs[psy->properties[i]]);
+
+ return;
+}
+
+static char *kstruprdup(const char *str, gfp_t gfp)
+{
+ char *ret, *ustr;
+
+ ustr = ret = kmalloc(strlen(str) + 1, gfp);
+
+ if (!ret)
+ return NULL;
+
+ while (*str)
+ *ustr++ = toupper(*str++);
+
+ *ustr = 0;
+
+ return ret;
+}
+
+int power_supply_uevent(struct device *dev, char **envp, int num_envp,
+ char *buffer, int buffer_size)
+{
+ struct power_supply *psy = dev_get_drvdata(dev);
+ int i = 0, length = 0, ret = 0, j;
+ char *prop_buf;
+ char *attrname;
+
+ dev_dbg(dev, "uevent\n");
+
+ if (!psy) {
+ dev_dbg(dev, "No power supply yet\n");
+ return ret;
+ }
+
+ dev_dbg(dev, "POWER_SUPPLY_NAME=%s\n", psy->name);
+
+ ret = add_uevent_var(envp, num_envp, &i, buffer, buffer_size,
+ &length, "POWER_SUPPLY_NAME=%s", psy->name);
+ if (ret)
+ return ret;
+
+ prop_buf = (char *)get_zeroed_page(GFP_KERNEL);
+ if (!prop_buf)
+ return -ENOMEM;
+
+ for (j = 0; j < ARRAY_SIZE(power_supply_static_attrs); j++) {
+ struct device_attribute *attr;
+ char *line;
+
+ attr = &power_supply_static_attrs[j];
+
+ ret = power_supply_show_static_attrs(dev, attr, prop_buf);
+ if (ret < 0)
+ goto out;
+
+ line = strchr(prop_buf, '\n');
+ if (line)
+ *line = 0;
+
+ attrname = kstruprdup(attr->attr.name, GFP_KERNEL);
+ if (!attrname) {
+ ret = -ENOMEM;
+ goto out;
+ }
+
+ dev_dbg(dev, "Static prop %s=%s\n", attrname, prop_buf);
+
+ ret = add_uevent_var(envp, num_envp, &i, buffer, buffer_size,
+ &length, "POWER_SUPPLY_%s=%s",
+ attrname, prop_buf);
+ kfree(attrname);
+ if (ret)
+ goto out;
+ }
+
+ dev_dbg(dev, "%zd dynamic props\n", psy->num_properties);
+
+ for (j = 0; j < psy->num_properties; j++) {
+ struct device_attribute *attr;
+ char *line;
+
+ attr = &power_supply_attrs[psy->properties[j]];
+
+ ret = power_supply_show_property(dev, attr, prop_buf);
+ if (ret == -ENODEV) {
+ /* When a battery is absent, we expect -ENODEV. Don't abort;
+ send the uevent with at least the the PRESENT=0 property */
+ ret = 0;
+ continue;
+ }
+
+ if (ret < 0)
+ goto out;
+
+ line = strchr(prop_buf, '\n');
+ if (line)
+ *line = 0;
+
+ attrname = kstruprdup(attr->attr.name, GFP_KERNEL);
+ if (!attrname) {
+ ret = -ENOMEM;
+ goto out;
+ }
+
+ dev_dbg(dev, "prop %s=%s\n", attrname, prop_buf);
+
+ ret = add_uevent_var(envp, num_envp, &i, buffer, buffer_size,
+ &length, "POWER_SUPPLY_%s=%s",
+ attrname, prop_buf);
+ kfree(attrname);
+ if (ret)
+ goto out;
+ }
+
+out:
+ free_page((unsigned long)prop_buf);
+
+ return ret;
+}