2012-05-20 12:06:07

by Alex Hung

[permalink] [raw]
Subject: [PATCH] ACPI: battery: fix battery->alarm is updated when it is not supported

battery alarm is checked whether BIOS supports it before past to BIOS;
however, the value is updatd without being checked. This causes alarm return
an incorrect value that never represents an actual state BIOS is in.

Signed-off-by: Alex Hung <[email protected]>
---
drivers/acpi/battery.c | 6 ++++--
1 files changed, 4 insertions(+), 2 deletions(-)

diff --git a/drivers/acpi/battery.c b/drivers/acpi/battery.c
index 86933ca..14548e8 100644
--- a/drivers/acpi/battery.c
+++ b/drivers/acpi/battery.c
@@ -535,7 +535,8 @@ static ssize_t acpi_battery_alarm_store(struct device *dev,
{
unsigned long x;
struct acpi_battery *battery = to_acpi_battery(dev_get_drvdata(dev));
- if (sscanf(buf, "%ld\n", &x) == 1)
+ if (sscanf(buf, "%ld\n", &x) == 1 &&
+ test_bit(ACPI_BATTERY_ALARM_PRESENT, &battery->flags))
battery->alarm = x/1000;
if (acpi_battery_present(battery))
acpi_battery_set_alarm(battery);
@@ -805,7 +806,8 @@ static ssize_t acpi_battery_write_alarm(struct file *file,
goto end;
}
alarm_string[count] = '\0';
- battery->alarm = simple_strtol(alarm_string, NULL, 0);
+ if (test_bit(ACPI_BATTERY_ALARM_PRESENT, &battery->flags))
+ battery->alarm = simple_strtol(alarm_string, NULL, 0);
result = acpi_battery_set_alarm(battery);
end:
if (!result)
--
1.7.0.4