2024-06-09 11:13:45

by Thomas Weißschuh

[permalink] [raw]
Subject: [PATCH] ACPI: SBS: manage alarm sysfs attribute through psy core

Let the power supply core register the attribute.
This ensures that the attribute is created before the device is
announced to userspace, avoiding a race condition.

Signed-off-by: Thomas Weißschuh <[email protected]>
---
Only compile-tested.

This is the SBS equivalent of
"ACPI: battery: create alarm sysfs attribute atomically" [0]

[0] https://lore.kernel.org/lkml/20240609-acpi-battery-cleanup-v1-5-344517bdca73@weisss
---
drivers/acpi/sbs.c | 23 ++++++++++++-----------
1 file changed, 12 insertions(+), 11 deletions(-)

diff --git a/drivers/acpi/sbs.c b/drivers/acpi/sbs.c
index dc8164b182dc..442c5905d43b 100644
--- a/drivers/acpi/sbs.c
+++ b/drivers/acpi/sbs.c
@@ -77,7 +77,6 @@ struct acpi_battery {
u16 spec;
u8 id;
u8 present:1;
- u8 have_sysfs_alarm:1;
};

#define to_acpi_battery(x) power_supply_get_drvdata(x)
@@ -462,12 +461,18 @@ static ssize_t acpi_battery_alarm_store(struct device *dev,
return count;
}

-static const struct device_attribute alarm_attr = {
+static struct device_attribute alarm_attr = {
.attr = {.name = "alarm", .mode = 0644},
.show = acpi_battery_alarm_show,
.store = acpi_battery_alarm_store,
};

+static struct attribute *acpi_battery_attrs[] = {
+ &alarm_attr.attr,
+ NULL
+};
+ATTRIBUTE_GROUPS(acpi_battery);
+
/* --------------------------------------------------------------------------
Driver Interface
-------------------------------------------------------------------------- */
@@ -518,7 +523,10 @@ static int acpi_battery_read(struct acpi_battery *battery)
static int acpi_battery_add(struct acpi_sbs *sbs, int id)
{
struct acpi_battery *battery = &sbs->battery[id];
- struct power_supply_config psy_cfg = { .drv_data = battery, };
+ struct power_supply_config psy_cfg = {
+ .drv_data = battery,
+ .attr_grp = acpi_battery_groups,
+ };
int result;

battery->id = id;
@@ -548,10 +556,6 @@ static int acpi_battery_add(struct acpi_sbs *sbs, int id)
goto end;
}

- result = device_create_file(&battery->bat->dev, &alarm_attr);
- if (result)
- goto end;
- battery->have_sysfs_alarm = 1;
end:
pr_info("%s [%s]: Battery Slot [%s] (battery %s)\n",
ACPI_SBS_DEVICE_NAME, acpi_device_bid(sbs->device),
@@ -563,11 +567,8 @@ static void acpi_battery_remove(struct acpi_sbs *sbs, int id)
{
struct acpi_battery *battery = &sbs->battery[id];

- if (battery->bat) {
- if (battery->have_sysfs_alarm)
- device_remove_file(&battery->bat->dev, &alarm_attr);
+ if (battery->bat)
power_supply_unregister(battery->bat);
- }
}

static int acpi_charger_add(struct acpi_sbs *sbs)

---
base-commit: 771ed66105de9106a6f3e4311e06451881cdac5e
change-id: 20240609-acpi-sbs-sysfs-group-50a30dc5f82a

Best regards,
--
Thomas Weißschuh <[email protected]>



2024-06-13 19:31:47

by Rafael J. Wysocki

[permalink] [raw]
Subject: Re: [PATCH] ACPI: SBS: manage alarm sysfs attribute through psy core

On Sun, Jun 9, 2024 at 1:13 PM Thomas Weißschuh <[email protected]> wrote:
>
> Let the power supply core register the attribute.
> This ensures that the attribute is created before the device is
> announced to userspace, avoiding a race condition.
>
> Signed-off-by: Thomas Weißschuh <[email protected]>
> ---
> Only compile-tested.
>
> This is the SBS equivalent of
> "ACPI: battery: create alarm sysfs attribute atomically" [0]
>
> [0] https://lore.kernel.org/lkml/20240609-acpi-battery-cleanup-v1-5-344517bdca73@weisss
> ---
> drivers/acpi/sbs.c | 23 ++++++++++++-----------
> 1 file changed, 12 insertions(+), 11 deletions(-)
>
> diff --git a/drivers/acpi/sbs.c b/drivers/acpi/sbs.c
> index dc8164b182dc..442c5905d43b 100644
> --- a/drivers/acpi/sbs.c
> +++ b/drivers/acpi/sbs.c
> @@ -77,7 +77,6 @@ struct acpi_battery {
> u16 spec;
> u8 id;
> u8 present:1;
> - u8 have_sysfs_alarm:1;
> };
>
> #define to_acpi_battery(x) power_supply_get_drvdata(x)
> @@ -462,12 +461,18 @@ static ssize_t acpi_battery_alarm_store(struct device *dev,
> return count;
> }
>
> -static const struct device_attribute alarm_attr = {
> +static struct device_attribute alarm_attr = {
> .attr = {.name = "alarm", .mode = 0644},
> .show = acpi_battery_alarm_show,
> .store = acpi_battery_alarm_store,
> };
>
> +static struct attribute *acpi_battery_attrs[] = {
> + &alarm_attr.attr,
> + NULL
> +};
> +ATTRIBUTE_GROUPS(acpi_battery);
> +
> /* --------------------------------------------------------------------------
> Driver Interface
> -------------------------------------------------------------------------- */
> @@ -518,7 +523,10 @@ static int acpi_battery_read(struct acpi_battery *battery)
> static int acpi_battery_add(struct acpi_sbs *sbs, int id)
> {
> struct acpi_battery *battery = &sbs->battery[id];
> - struct power_supply_config psy_cfg = { .drv_data = battery, };
> + struct power_supply_config psy_cfg = {
> + .drv_data = battery,
> + .attr_grp = acpi_battery_groups,
> + };
> int result;
>
> battery->id = id;
> @@ -548,10 +556,6 @@ static int acpi_battery_add(struct acpi_sbs *sbs, int id)
> goto end;
> }
>
> - result = device_create_file(&battery->bat->dev, &alarm_attr);
> - if (result)
> - goto end;
> - battery->have_sysfs_alarm = 1;
> end:
> pr_info("%s [%s]: Battery Slot [%s] (battery %s)\n",
> ACPI_SBS_DEVICE_NAME, acpi_device_bid(sbs->device),
> @@ -563,11 +567,8 @@ static void acpi_battery_remove(struct acpi_sbs *sbs, int id)
> {
> struct acpi_battery *battery = &sbs->battery[id];
>
> - if (battery->bat) {
> - if (battery->have_sysfs_alarm)
> - device_remove_file(&battery->bat->dev, &alarm_attr);
> + if (battery->bat)
> power_supply_unregister(battery->bat);
> - }
> }
>
> static int acpi_charger_add(struct acpi_sbs *sbs)
>
> ---

Applied as 6.11 material, thanks!