[PATCHv1 05/14] power: supply: lp8788: fix race-condition in sysfs registration

From: Sebastian Reichel
Date: Sun Sep 30 2018 - 18:04:23 EST


This registers custom sysfs properties using the native functionality
of the power-supply framework, which cleans up the code a bit and
fixes a race-condition. Before this patch the sysfs attributes were
not properly registered to udev.

Signed-off-by: Sebastian Reichel <sebastian.reichel@xxxxxxxxxxxxx>
---
drivers/power/supply/lp8788-charger.c | 62 ++++++++++++---------------
1 file changed, 27 insertions(+), 35 deletions(-)

diff --git a/drivers/power/supply/lp8788-charger.c b/drivers/power/supply/lp8788-charger.c
index 0f3432795f3c..309e6efbb8ef 100644
--- a/drivers/power/supply/lp8788-charger.c
+++ b/drivers/power/supply/lp8788-charger.c
@@ -410,30 +410,6 @@ static const struct power_supply_desc lp8788_psy_battery_desc = {
.get_property = lp8788_battery_get_property,
};

-static int lp8788_psy_register(struct platform_device *pdev,
- struct lp8788_charger *pchg)
-{
- struct power_supply_config charger_cfg = {};
-
- charger_cfg.supplied_to = battery_supplied_to;
- charger_cfg.num_supplicants = ARRAY_SIZE(battery_supplied_to);
-
- pchg->charger = power_supply_register(&pdev->dev,
- &lp8788_psy_charger_desc,
- &charger_cfg);
- if (IS_ERR(pchg->charger))
- return -EPERM;
-
- pchg->battery = power_supply_register(&pdev->dev,
- &lp8788_psy_battery_desc, NULL);
- if (IS_ERR(pchg->battery)) {
- power_supply_unregister(pchg->charger);
- return -EPERM;
- }
-
- return 0;
-}
-
static void lp8788_psy_unregister(struct lp8788_charger *pchg)
{
power_supply_unregister(pchg->battery);
@@ -690,16 +666,39 @@ static DEVICE_ATTR(charger_status, S_IRUSR, lp8788_show_charger_status, NULL);
static DEVICE_ATTR(eoc_time, S_IRUSR, lp8788_show_eoc_time, NULL);
static DEVICE_ATTR(eoc_level, S_IRUSR, lp8788_show_eoc_level, NULL);

-static struct attribute *lp8788_charger_attr[] = {
+static struct attribute *lp8788_charger_sysfs_attrs[] = {
&dev_attr_charger_status.attr,
&dev_attr_eoc_time.attr,
&dev_attr_eoc_level.attr,
NULL,
};

-static const struct attribute_group lp8788_attr_group = {
- .attrs = lp8788_charger_attr,
-};
+ATTRIBUTE_GROUPS(lp8788_charger_sysfs);
+
+static int lp8788_psy_register(struct platform_device *pdev,
+ struct lp8788_charger *pchg)
+{
+ struct power_supply_config charger_cfg = {};
+
+ charger_cfg.attr_grp = lp8788_charger_sysfs_groups;
+ charger_cfg.supplied_to = battery_supplied_to;
+ charger_cfg.num_supplicants = ARRAY_SIZE(battery_supplied_to);
+
+ pchg->charger = power_supply_register(&pdev->dev,
+ &lp8788_psy_charger_desc,
+ &charger_cfg);
+ if (IS_ERR(pchg->charger))
+ return -EPERM;
+
+ pchg->battery = power_supply_register(&pdev->dev,
+ &lp8788_psy_battery_desc, NULL);
+ if (IS_ERR(pchg->battery)) {
+ power_supply_unregister(pchg->charger);
+ return -EPERM;
+ }
+
+ return 0;
+}

static int lp8788_charger_probe(struct platform_device *pdev)
{
@@ -726,12 +725,6 @@ static int lp8788_charger_probe(struct platform_device *pdev)
if (ret)
return ret;

- ret = sysfs_create_group(&pdev->dev.kobj, &lp8788_attr_group);
- if (ret) {
- lp8788_psy_unregister(pchg);
- return ret;
- }
-
ret = lp8788_irq_register(pdev, pchg);
if (ret)
dev_warn(dev, "failed to register charger irq: %d\n", ret);
@@ -745,7 +738,6 @@ static int lp8788_charger_remove(struct platform_device *pdev)

flush_work(&pchg->charger_work);
lp8788_irq_unregister(pdev, pchg);
- sysfs_remove_group(&pdev->dev.kobj, &lp8788_attr_group);
lp8788_psy_unregister(pchg);
lp8788_release_adc_channel(pchg);

--
2.19.0