UPSTREAM: power_supply: fix return value of get_property

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. Lastly, modify the check in
power_supply_show_property() to also ignore -EAGAIN when so it
doesn't complain about not returning the property.

Change-Id: I8a710802534c033d64589d8d213eeaa36d9cc7d7
Signed-off-by: Rhyland Klein <rklein@nvidia.com>
Signed-off-by: Sebastian Reichel <sre@kernel.org>
Signed-off-by: Caesar Wang <wxt@rock-chips.com>
(cherry picked from commit e380538529e83c5d3fd27e8cbfcc1f9799cb6bbb)

diff --git a/drivers/power/power_supply_core.c b/drivers/power/power_supply_core.c
index b13cd074c52afc90c086bc16cc011b7adb0ac91f..a74d8ca383a1e8cb040ca08f78b7c77d15821375 100644 (file)
--- 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);
 }
@@ -785,6 +788,7 @@ __power_supply_register(struct device *parent,
         *    after calling power_supply_register()).
         */
        atomic_inc(&psy->use_cnt);
+       psy->initialized = true;
 
        queue_delayed_work(system_power_efficient_wq,
                           &psy->deferred_register_work,

diff --git a/drivers/power/power_supply_sysfs.c b/drivers/power/power_supply_sysfs.c
index 280018d59d5a60fab0b7d97145bbff25761bd8aa..f94054dd2f2c56b54b7c2e2ac35fcf5ac7ca5cec 100644 (file)
--- a/drivers/power/power_supply_sysfs.c
+++ b/drivers/power/power_supply_sysfs.c
@@ -82,7 +82,7 @@ static ssize_t power_supply_show_property(struct device *dev,
                        if (ret == -ENODATA)
                                dev_dbg(dev, "driver has no data for `%s' property\n",
                                        attr->attr.name);
-                       else if (ret != -ENODEV)
+                       else if (ret != -ENODEV && ret != -EAGAIN)
                                dev_err(dev, "driver failed to report `%s' property: %zd\n",
                                        attr->attr.name, ret);
                        return ret;

diff --git a/include/linux/power_supply.h b/include/linux/power_supply.h
index d43778bd6a07579281ea464d9e15a406a4031831..3241026e49f6863a94e616c84eea431d2c205786 100644 (file)
--- a/include/linux/power_supply.h
+++ b/include/linux/power_supply.h
@@ -254,6 +254,7 @@ 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;