Am 19.09.22 um 21:12 schrieb Armin Wolf:
Am 19.09.22 um 18:27 schrieb Rafael J. Wysocki:
On Mon, Sep 19, 2022 at 12:42 PM Hans de Goede <hdegoede@xxxxxxxxxx>
wrote:
Hi,
On 9/12/22 13:53, Armin Wolf wrote:
Currently, battery hooks are being unloaded if they return
an error when adding a single battery.
This however also causes the removal of successfully added
hooks if they return -ENODEV for a single unsupported
battery.
Do not unload battery hooks in such cases since the hook
handles any cleanup actions.
Signed-off-by: Armin Wolf <W_Armin@xxxxxx>
Maybe instead of removing all error checking, allow -ENODEV
and behave as before when the error is not -ENODEV ?
Otherwise we should probably make the add / remove callbacks
void to indicate that any errors are ignored.
Rafael, do you have any opinion on this?
IMV this is not a completely safe change, because things may simply
not work in the cases in which an error is returned.
It would be somewhat better to use a special error code to indicate
"no support" (eg. -ENOTSUPP) and ignore that one only.
I would favor -ENODEV then, since it is already used by quiet a few
drivers
to indicate a unsupported battery.
Armin Wolf
While checking all instances where the battery hook mechanism is currently used,
i found out that all but a single battery hook return -ENODEV for all errors they
encounter, the exception being the huawei-wmi driver.
I do not know the reason for this, but i fear unloading the extension on for
example -ENOTSUP will result in similar behavior by hooks wanting to avoid being
unloaded on harmless errors.
However, i agree that when ignoring all errors, battery extensions which provide
similar attributes may currently delete each others attributes.
Any idea on how to solve this?
Armin Wolf
---
drivers/acpi/battery.c | 24 +++---------------------
1 file changed, 3 insertions(+), 21 deletions(-)
diff --git a/drivers/acpi/battery.c b/drivers/acpi/battery.c
index 306513fec1e1..e59c261c7c59 100644
--- a/drivers/acpi/battery.c
+++ b/drivers/acpi/battery.c
@@ -724,20 +724,10 @@ void battery_hook_register(struct
acpi_battery_hook *hook)
* its attributes.
*/
list_for_each_entry(battery, &acpi_battery_list, list) {
- if (hook->add_battery(battery->bat)) {
- /*
- * If a add-battery returns non-zero,
- * the registration of the extension has failed,
- * and we will not add it to the list of loaded
- * hooks.
- */
- pr_err("extension failed to load: %s",
hook->name);
- __battery_hook_unregister(hook, 0);
- goto end;
- }
+ hook->add_battery(battery->bat);
}
pr_info("new extension: %s\n", hook->name);
-end:
+
mutex_unlock(&hook_mutex);
}
EXPORT_SYMBOL_GPL(battery_hook_register);
@@ -762,15 +752,7 @@ static void battery_hook_add_battery(struct
acpi_battery *battery)
* during the battery module initialization.
*/
list_for_each_entry_safe(hook_node, tmp, &battery_hook_list,
list) {
- if (hook_node->add_battery(battery->bat)) {
- /*
- * The notification of the extensions has
failed, to
- * prevent further errors we will unload the
extension.
- */
- pr_err("error in extension, unloading: %s",
- hook_node->name);
- __battery_hook_unregister(hook_node, 0);
- }
+ hook_node->add_battery(battery->bat);
}
mutex_unlock(&hook_mutex);
}
--
2.30.2
