[PATCH 1/1] battery: only refresh the sysfs files when pertinant information changes

From: Andy Whitcroft
Date: Thu May 03 2012 - 09:48:32 EST


We only need to regenerate the sysfs files when the capacity units
change, avoid the update otherwise.

Signed-off-by: Andy Whitcroft <apw@xxxxxxxxxxxxx>
---
drivers/acpi/battery.c | 10 +++++++++-
1 file changed, 9 insertions(+), 1 deletion(-)

Based on Matthew's feedback here is a version which optimises
based on the power_unit field as returned from the battery info.
Could someone who suffers from this issue please test this out
and report back. Thanks.

diff --git a/drivers/acpi/battery.c b/drivers/acpi/battery.c
index 86933ca..7dd3f9f 100644
--- a/drivers/acpi/battery.c
+++ b/drivers/acpi/battery.c
@@ -643,11 +643,19 @@ static int acpi_battery_update(struct acpi_battery *battery)

static void acpi_battery_refresh(struct acpi_battery *battery)
{
+ int power_unit;
+
if (!battery->bat.dev)
return;

+ power_unit = battery->power_unit;
+
acpi_battery_get_info(battery);
- /* The battery may have changed its reporting units. */
+
+ if (power_unit == battery->power_unit)
+ return;
+
+ /* The battery has changed its reporting units. */
sysfs_remove_battery(battery);
sysfs_add_battery(battery);
}
--
1.7.9.5

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