This patch adds support for writeable power supply properties and
exposes them as writeable to sysfs.
A power supply implementation must implement two new function calls in
order to use that feature:
int set_property(struct power_supply *psy,
enum power_supply_property psp,
const union power_supply_propval *val);
int property_is_writeable(struct power_supply *psy,
enum power_supply_property psp);
Signed-off-by: Daniel Mack <daniel@caiaq.de>
Cc: Anton Vorontsov <cbou@mail.ru>
Cc: David Woodhouse <dwmw2@infradead.org>
Cc: Andres Salomon <dilinger@collabora.co.uk>
Cc: Alexey Starikovskiy <astarikovskiy@suse.de>
Cc: Len Brown <len.brown@intel.com>
Cc: Mark Brown <broonie@opensource.wolfsonmicro.com>
Cc: Matt Reimer <mreimer@vpop.net>
Cc: Evgeniy Polyakov <zbr@ioremap.net>
Cc: Tejun Heo <tj@kernel.org>
---
drivers/power/power_supply_sysfs.c | 31 +++++++++++++++++++++++++++++--
include/linux/power_supply.h | 5 +++++
2 files changed, 34 insertions(+), 2 deletions(-)
diff --git a/drivers/power/power_supply_sysfs.c b/drivers/power/power_supply_sysfs.c
index 5b6e352..5cfb410 100644
--- a/drivers/power/power_supply_sysfs.c
+++ b/drivers/power/power_supply_sysfs.c
@@ -31,9 +31,9 @@
#define POWER_SUPPLY_ATTR(_name) \
{ \
- .attr = { .name = #_name, .mode = 0444 }, \
+ .attr = { .name = #_name }, \
.show = power_supply_show_property, \
- .store = NULL, \
+ .store = power_supply_store_property, \
}
static struct device_attribute power_supply_attrs[];
@@ -91,6 +91,25 @@ static ssize_t power_supply_show_property(struct device *dev,
return sprintf(buf, "%d\n", value.intval);
}
+static ssize_t power_supply_store_property(struct device *dev,
+ struct device_attribute *attr,
+ const char *buf, size_t count) {
+ ssize_t ret;
+ struct power_supply *psy = dev_get_drvdata(dev);
+ const ptrdiff_t off = attr - power_supply_attrs;
+ union power_supply_propval value;
+ long long_val;
+
+ /* TODO: support other types than int */
+ ret = strict_strtol(buf, 10, &long_val);
+ if (ret < 0)
+ return ret;
+
+ value.intval = long_val;
+
+ return psy->set_property(psy, off, &value);
+}
+
/* Must be in the same order as POWER_SUPPLY_PROP_* */
static struct device_attribute power_supply_attrs[] = {
/* Properties of type `int' */
@@ -164,6 +183,14 @@ int power_supply_create_attrs(struct power_supply *psy)
}
for (j = 0; j < psy->num_properties; j++) {
+ mode_t mode = S_IRUSR | S_IRGRP | S_IROTH;
+
+ if (psy->property_is_writeable &&
+ psy->property_is_writeable(psy, psy->properties[j]) > 0)
+ mode |= S_IWUSR;
+
+ power_supply_attrs[psy->properties[j]].attr.mode = mode;
+
rc = device_create_file(psy->dev,
&power_supply_attrs[psy->properties[j]]);
if (rc)
diff --git a/include/linux/power_supply.h b/include/linux/power_supply.h
index ebd2b8f..f02f7fd 100644
--- a/include/linux/power_supply.h
+++ b/include/linux/power_supply.h
@@ -144,6 +144,11 @@ struct power_supply {
int (*get_property)(struct power_supply *psy,
enum power_supply_property psp,
union power_supply_propval *val);
+ int (*set_property)(struct power_supply *psy,
+ enum power_supply_property psp,
+ const union power_supply_propval *val);
+ int (*property_is_writeable)(struct power_supply *psy,
+ enum power_supply_property psp);
void (*external_power_changed)(struct power_supply *psy);
void (*set_charged)(struct power_supply *psy);
--
1.6.3.3
--
