From 0011d2d4a5f7bb5666dcfb9f9b3dbdb084ab98f1 Mon Sep 17 00:00:00 2001 From: Daniel Mack Date: Tue, 18 May 2010 21:49:52 +0200 Subject: [PATCH] power_supply: Add support for writeable properties 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 Cc: David Woodhouse Cc: Alexey Starikovskiy Cc: Len Brown Cc: Mark Brown Cc: Matt Reimer Cc: Evgeniy Polyakov Cc: Tejun Heo Signed-off-by: Anton Vorontsov --- drivers/power/power_supply_sysfs.c | 38 +++++++++++++++++++++++++++++++++++--- include/linux/power_supply.h | 5 +++++ 2 files changed, 40 insertions(+), 3 deletions(-) diff --git a/drivers/power/power_supply_sysfs.c b/drivers/power/power_supply_sysfs.c index 7d7593c..6a86cdf 100644 --- a/drivers/power/power_supply_sysfs.c +++ b/drivers/power/power_supply_sysfs.c @@ -33,7 +33,7 @@ { \ .attr = { .name = #_name }, \ .show = power_supply_show_property, \ - .store = NULL, \ + .store = power_supply_store_property, \ } static struct device_attribute power_supply_attrs[]; @@ -99,6 +99,29 @@ 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; + + ret = psy->set_property(psy, off, &value); + if (ret < 0) + return ret; + + return count; +} + /* Must be in the same order as POWER_SUPPLY_PROP_* */ static struct device_attribute power_supply_attrs[] = { /* Properties of type `int' */ @@ -159,8 +182,17 @@ static mode_t power_supply_attr_is_visible(struct kobject *kobj, int i; for (i = 0; i < psy->num_properties; i++) { - if (psy->properties[i] == attrno) - return 0444; + int property = psy->properties[i]; + + if (property == attrno) { + mode_t mode = S_IRUSR | S_IRGRP | S_IROTH; + + if (psy->property_is_writeable && + psy->property_is_writeable(psy, property) > 0) + mode |= S_IWUSR; + + return mode; + } } return 0; diff --git a/include/linux/power_supply.h b/include/linux/power_supply.h index c5f73a3..30083a8 100644 --- a/include/linux/power_supply.h +++ b/include/linux/power_supply.h @@ -145,6 +145,11 @@ 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); -- 2.7.4