diff options
| author |   Krzysztof Kozlowski <k.kozlowski@samsung.com> | 2015-05-19 16:16:29 +0900 |
|---|---|---|
| committer |   Sebastian Reichel <sre@kernel.org> | 2015-05-23 20:06:19 +0200 |
| commit | a9f6a19b57c4f37dfd6aa322071948245fecbd91 (patch) | |
| tree | 8a9534550a92c9a0de9da18026d447bcc8e6eb06 /drivers/power | |
| parent | power: reset: ltc2952: use _optional variant of devm_gpiod_get (diff) | |
| download | linux-dev-a9f6a19b57c4f37dfd6aa322071948245fecbd91.tar.xz linux-dev-a9f6a19b57c4f37dfd6aa322071948245fecbd91.zip | |
power_supply: Use wrappers to avoid races when registering power supply
Use wrappers over get_property() and set_property() internally in power
supply and for sysfs interface. The wrappers provide safe access if
power supply is not yet registered or t is being destroyed.
In case of syfs the theoretical race could happen between ending of
driver's probe and parallel sysfs access:
some_driver_probe() userspace
==================================== ===========================
drv->psy = power_supply_register()
device_add()
sysfs entries are created
atomic_inc(&psy->use_cnt);
store on sysfs attributes
drv->set_property()
dereference of drv->psy
drv->psy = returned psy;
For leds the race could happen between power supply being destroyed and
ongoing power_supply_changed_work().
Signed-off-by: Krzysztof Kozlowski <k.kozlowski@samsung.com>
Signed-off-by: Sebastian Reichel <sre@kernel.org>
Diffstat (limited to 'drivers/power')
| -rw-r--r-- | drivers/power/power_supply_leds.c | 4 | ||||
| -rw-r--r-- | drivers/power/power_supply_sysfs.c | 2 |
2 files changed, 3 insertions, 3 deletions
diff --git a/drivers/power/power_supply_leds.c b/drivers/power/power_supply_leds.c index 2d41a43fc81a..2277ad9c2f68 100644 --- a/drivers/power/power_supply_leds.c +++ b/drivers/power/power_supply_leds.c @@ -25,7 +25,7 @@ static void power_supply_update_bat_leds(struct power_supply *psy) unsigned long delay_on = 0; unsigned long delay_off = 0; - if (psy->desc->get_property(psy, POWER_SUPPLY_PROP_STATUS, &status)) + if (power_supply_get_property(psy, POWER_SUPPLY_PROP_STATUS, &status)) return; dev_dbg(&psy->dev, "%s %d\n", __func__, status.intval); @@ -115,7 +115,7 @@ static void power_supply_update_gen_leds(struct power_supply *psy) { union power_supply_propval online; - if (psy->desc->get_property(psy, POWER_SUPPLY_PROP_ONLINE, &online)) + if (power_supply_get_property(psy, POWER_SUPPLY_PROP_ONLINE, &online)) return; dev_dbg(&psy->dev, "%s %d\n", __func__, online.intval); diff --git a/drivers/power/power_supply_sysfs.c b/drivers/power/power_supply_sysfs.c index 9134e3d2d95e..af026806cba5 100644 --- a/drivers/power/power_supply_sysfs.c +++ b/drivers/power/power_supply_sysfs.c @@ -125,7 +125,7 @@ static ssize_t power_supply_store_property(struct device *dev, value.intval = long_val; - ret = psy->desc->set_property(psy, off, &value); + ret = power_supply_set_property(psy, off, &value); if (ret < 0) return ret; |