power_supply_get_property() should ideally return -EAGAIN if it is
called while the power_supply is being registered. There was no way
previously to determine if use_cnt == 0 meant that the power_supply
wasn't fully registered yet, or if it had already been unregistered.
Add a new boolean to the power_supply struct to simply show if
registration is completed.
Signed-off-by: Rhyland Klein <rkl...@nvidia.com>
---
This patch continues what was discussed with the patch
"power_supply: power_supply_read_temp only if use_cnt > 0".
Looking at the thermal code, it looks like we should indeed return
EAGAIN if possible, and since this change is fairly simple, I think
it makes sense to do it.
drivers/power/power_supply_core.c | 6 +++++-
include/linux/power_supply.h | 1 +
2 files changed, 6 insertions(+), 1 deletion(-)
diff --git a/drivers/power/power_supply_core.c
b/drivers/power/power_supply_core.c
index b13cd074c52a..a39a47672979 100644
--- a/drivers/power/power_supply_core.c
+++ b/drivers/power/power_supply_core.c
@@ -491,8 +491,11 @@ int power_supply_get_property(struct power_supply *psy,
enum power_supply_property psp,
union power_supply_propval *val)
{
- if (atomic_read(&psy->use_cnt) <= 0)
+ if (atomic_read(&psy->use_cnt) <= 0) {
+ if (!psy->initialized)
+ return -EAGAIN;
return -ENODEV;
+ }
return psy->desc->get_property(psy, psp, val);
}
@@ -775,6 +778,7 @@ __power_supply_register(struct device *parent,
if (rc)
goto create_triggers_failed;
+ psy->initialized = true;
/*
* Update use_cnt after any uevents (most notably from device_add()).
* We are here still during driver's probe but
diff --git a/include/linux/power_supply.h b/include/linux/power_supply.h
index 751061790626..3965503315ef 100644
--- a/include/linux/power_supply.h
+++ b/include/linux/power_supply.h
@@ -248,6 +248,7 @@ struct power_supply {
struct delayed_work deferred_register_work;
spinlock_t changed_lock;
bool changed;
+ bool initialized;
atomic_t use_cnt;
#ifdef CONFIG_THERMAL
struct thermal_zone_device *tzd;
--
1.9.1
