[PATCHv1 09/14] power: supply: charger-manager: fix race-condition in sysfs registration
From: Sebastian Reichel
Date: Sun Sep 30 2018 - 18:04:29 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/charger-manager.c | 51 +++++++++++---------------
include/linux/power/charger-manager.h | 3 +-
2 files changed, 24 insertions(+), 30 deletions(-)
diff --git a/drivers/power/supply/charger-manager.c b/drivers/power/supply/charger-manager.c
index 7ce0a4a2645c..dab68c6af77a 100644
--- a/drivers/power/supply/charger-manager.c
+++ b/drivers/power/supply/charger-manager.c
@@ -1352,7 +1352,7 @@ static ssize_t charger_externally_control_store(struct device *dev,
}
/**
- * charger_manager_register_sysfs - Register sysfs entry for each charger
+ * charger_manager_prepare_sysfs - Prepare sysfs entry for each charger
* @cm: the Charger Manager representing the battery.
*
* This function add sysfs entry for charger(regulator) to control charger from
@@ -1364,13 +1364,12 @@ static ssize_t charger_externally_control_store(struct device *dev,
* externally_control, this charger isn't controlled from charger-manager and
* always stay off state of regulator.
*/
-static int charger_manager_register_sysfs(struct charger_manager *cm)
+static int charger_manager_prepare_sysfs(struct charger_manager *cm)
{
struct charger_desc *desc = cm->desc;
struct charger_regulator *charger;
int chargers_externally_control = 1;
char *name;
- int ret;
int i;
/* Create sysfs entry to control charger(regulator) */
@@ -1385,8 +1384,10 @@ static int charger_manager_register_sysfs(struct charger_manager *cm)
charger->attrs[1] = &charger->attr_state.attr;
charger->attrs[2] = &charger->attr_externally_control.attr;
charger->attrs[3] = NULL;
- charger->attr_g.name = name;
- charger->attr_g.attrs = charger->attrs;
+
+ charger->attr_grp.name = name;
+ charger->attr_grp.attrs = charger->attrs;
+ desc->sysfs_groups[i] = &charger->attr_grp;
sysfs_attr_init(&charger->attr_name.attr);
charger->attr_name.attr.name = "name";
@@ -1413,14 +1414,6 @@ static int charger_manager_register_sysfs(struct charger_manager *cm)
dev_info(cm->dev, "'%s' regulator's externally_control is %d\n",
charger->regulator_name, charger->externally_control);
-
- ret = sysfs_create_group(&cm->charger_psy->dev.kobj,
- &charger->attr_g);
- if (ret < 0) {
- dev_err(cm->dev, "Cannot create sysfs entry of %s regulator\n",
- charger->regulator_name);
- return ret;
- }
}
if (chargers_externally_control) {
@@ -1561,6 +1554,13 @@ static struct charger_desc *of_cm_parse_desc(struct device *dev)
desc->charger_regulators = chg_regs;
+ desc->sysfs_groups = devm_kcalloc(dev,
+ desc->num_charger_regulators + 1,
+ sizeof(*desc->sysfs_groups),
+ GFP_KERNEL);
+ if (!desc->sysfs_groups)
+ return ERR_PTR(-ENOMEM);
+
for_each_child_of_node(np, child) {
struct charger_cable *cables;
struct device_node *_child;
@@ -1767,6 +1767,15 @@ static int charger_manager_probe(struct platform_device *pdev)
INIT_DELAYED_WORK(&cm->fullbatt_vchk_work, fullbatt_vchk);
+ /* Register sysfs entry for charger(regulator) */
+ ret = charger_manager_prepare_sysfs(cm);
+ if (ret < 0) {
+ dev_err(&pdev->dev,
+ "Cannot prepare sysfs entry of regulators\n");
+ return ret;
+ }
+ psy_cfg.attr_grp = desc->sysfs_groups;
+
cm->charger_psy = power_supply_register(&pdev->dev,
&cm->charger_psy_desc,
&psy_cfg);
@@ -1783,14 +1792,6 @@ static int charger_manager_probe(struct platform_device *pdev)
goto err_reg_extcon;
}
- /* Register sysfs entry for charger(regulator) */
- ret = charger_manager_register_sysfs(cm);
- if (ret < 0) {
- dev_err(&pdev->dev,
- "Cannot initialize sysfs entry of regulator\n");
- goto err_reg_sysfs;
- }
-
/* Add to the list */
mutex_lock(&cm_list_mtx);
list_add(&cm->entry, &cm_list);
@@ -1814,14 +1815,6 @@ static int charger_manager_probe(struct platform_device *pdev)
return 0;
-err_reg_sysfs:
- for (i = 0; i < desc->num_charger_regulators; i++) {
- struct charger_regulator *charger;
-
- charger = &desc->charger_regulators[i];
- sysfs_remove_group(&cm->charger_psy->dev.kobj,
- &charger->attr_g);
- }
err_reg_extcon:
for (i = 0; i < desc->num_charger_regulators; i++) {
struct charger_regulator *charger;
diff --git a/include/linux/power/charger-manager.h b/include/linux/power/charger-manager.h
index c4fa907c8f14..2ce8d00c20de 100644
--- a/include/linux/power/charger-manager.h
+++ b/include/linux/power/charger-manager.h
@@ -119,7 +119,7 @@ struct charger_regulator {
struct charger_cable *cables;
int num_cables;
- struct attribute_group attr_g;
+ struct attribute_group attr_grp;
struct device_attribute attr_name;
struct device_attribute attr_state;
struct device_attribute attr_externally_control;
@@ -186,6 +186,7 @@ struct charger_desc {
int num_charger_regulators;
struct charger_regulator *charger_regulators;
+ const struct attribute_group **sysfs_groups;
const char *psy_fuel_gauge;
--
2.19.0