2010-12-06 20:35:08

by Daniel Drake

[permalink] [raw]
Subject: [PATCH 1/2] power_supply: allow control of attribute visibility

A power supply driver could support a certain attribute that is not
available at runtime (e.g. because the specific host doesn't support
that functionality).

Add a mechanism for power supplies to be able to specify this.

Signed-off-by: Daniel Drake <[email protected]>
---
drivers/power/power_supply_sysfs.c | 4 ++++
include/linux/power_supply.h | 2 ++
2 files changed, 6 insertions(+), 0 deletions(-)

diff --git a/drivers/power/power_supply_sysfs.c b/drivers/power/power_supply_sysfs.c
index cd1f907..8df9e4c 100644
--- a/drivers/power/power_supply_sysfs.c
+++ b/drivers/power/power_supply_sysfs.c
@@ -191,6 +191,10 @@ static mode_t power_supply_attr_is_visible(struct kobject *kobj,
int property = psy->properties[i];

if (property == attrno) {
+ if (psy->property_is_available &&
+ !psy->property_is_available(psy, property))
+ return 0;
+
if (psy->property_is_writeable &&
psy->property_is_writeable(psy, property) > 0)
mode |= S_IWUSR;
diff --git a/include/linux/power_supply.h b/include/linux/power_supply.h
index 7d73256..b481458 100644
--- a/include/linux/power_supply.h
+++ b/include/linux/power_supply.h
@@ -152,6 +152,8 @@ struct power_supply {
int (*set_property)(struct power_supply *psy,
enum power_supply_property psp,
const union power_supply_propval *val);
+ bool (*property_is_available)(struct power_supply *psy,
+ enum power_supply_property psp);
int (*property_is_writeable)(struct power_supply *psy,
enum power_supply_property psp);
void (*external_power_changed)(struct power_supply *psy);
--
1.7.3.2