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path: root/drivers/acpi/battery.c
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Diffstat (limited to 'drivers/acpi/battery.c')
-rw-r--r--drivers/acpi/battery.c77
1 files changed, 77 insertions, 0 deletions
diff --git a/drivers/acpi/battery.c b/drivers/acpi/battery.c
index 7dd3f9fb9f3f..6ea287e22296 100644
--- a/drivers/acpi/battery.c
+++ b/drivers/acpi/battery.c
@@ -34,6 +34,7 @@
#include <linux/dmi.h>
#include <linux/slab.h>
#include <linux/suspend.h>
+#include <asm/unaligned.h>
#ifdef CONFIG_ACPI_PROCFS_POWER
#include <linux/proc_fs.h>
@@ -95,6 +96,18 @@ enum {
ACPI_BATTERY_ALARM_PRESENT,
ACPI_BATTERY_XINFO_PRESENT,
ACPI_BATTERY_QUIRK_PERCENTAGE_CAPACITY,
+ /* On Lenovo Thinkpad models from 2010 and 2011, the power unit
+ switches between mWh and mAh depending on whether the system
+ is running on battery or not. When mAh is the unit, most
+ reported values are incorrect and need to be adjusted by
+ 10000/design_voltage. Verified on x201, t410, t410s, and x220.
+ Pre-2010 and 2012 models appear to always report in mWh and
+ are thus unaffected (tested with t42, t61, t500, x200, x300,
+ and x230). Also, in mid-2012 Lenovo issued a BIOS update for
+ the 2011 models that fixes the issue (tested on x220 with a
+ post-1.29 BIOS), but as of Nov. 2012, no such update is
+ available for the 2010 models. */
+ ACPI_BATTERY_QUIRK_THINKPAD_MAH,
};
struct acpi_battery {
@@ -429,6 +442,21 @@ static int acpi_battery_get_info(struct acpi_battery *battery)
kfree(buffer.pointer);
if (test_bit(ACPI_BATTERY_QUIRK_PERCENTAGE_CAPACITY, &battery->flags))
battery->full_charge_capacity = battery->design_capacity;
+ if (test_bit(ACPI_BATTERY_QUIRK_THINKPAD_MAH, &battery->flags) &&
+ battery->power_unit && battery->design_voltage) {
+ battery->design_capacity = battery->design_capacity *
+ 10000 / battery->design_voltage;
+ battery->full_charge_capacity = battery->full_charge_capacity *
+ 10000 / battery->design_voltage;
+ battery->design_capacity_warning =
+ battery->design_capacity_warning *
+ 10000 / battery->design_voltage;
+ /* Curiously, design_capacity_low, unlike the rest of them,
+ is correct. */
+ /* capacity_granularity_* equal 1 on the systems tested, so
+ it's impossible to tell if they would need an adjustment
+ or not if their values were higher. */
+ }
return result;
}
@@ -477,6 +505,11 @@ static int acpi_battery_get_state(struct acpi_battery *battery)
&& battery->capacity_now >= 0 && battery->capacity_now <= 100)
battery->capacity_now = (battery->capacity_now *
battery->full_charge_capacity) / 100;
+ if (test_bit(ACPI_BATTERY_QUIRK_THINKPAD_MAH, &battery->flags) &&
+ battery->power_unit && battery->design_voltage) {
+ battery->capacity_now = battery->capacity_now *
+ 10000 / battery->design_voltage;
+ }
return result;
}
@@ -586,6 +619,24 @@ static void sysfs_remove_battery(struct acpi_battery *battery)
mutex_unlock(&battery->sysfs_lock);
}
+static void find_battery(const struct dmi_header *dm, void *private)
+{
+ struct acpi_battery *battery = (struct acpi_battery *)private;
+ /* Note: the hardcoded offsets below have been extracted from
+ the source code of dmidecode. */
+ if (dm->type == DMI_ENTRY_PORTABLE_BATTERY && dm->length >= 8) {
+ const u8 *dmi_data = (const u8 *)(dm + 1);
+ int dmi_capacity = get_unaligned((const u16 *)(dmi_data + 6));
+ if (dm->length >= 18)
+ dmi_capacity *= dmi_data[17];
+ if (battery->design_capacity * battery->design_voltage / 1000
+ != dmi_capacity &&
+ battery->design_capacity * 10 == dmi_capacity)
+ set_bit(ACPI_BATTERY_QUIRK_THINKPAD_MAH,
+ &battery->flags);
+ }
+}
+
/*
* According to the ACPI spec, some kinds of primary batteries can
* report percentage battery remaining capacity directly to OS.
@@ -611,6 +662,32 @@ static void acpi_battery_quirks(struct acpi_battery *battery)
battery->capacity_now = (battery->capacity_now *
battery->full_charge_capacity) / 100;
}
+
+ if (test_bit(ACPI_BATTERY_QUIRK_THINKPAD_MAH, &battery->flags))
+ return ;
+
+ if (battery->power_unit && dmi_name_in_vendors("LENOVO")) {
+ const char *s;
+ s = dmi_get_system_info(DMI_PRODUCT_VERSION);
+ if (s && !strnicmp(s, "ThinkPad", 8)) {
+ dmi_walk(find_battery, battery);
+ if (test_bit(ACPI_BATTERY_QUIRK_THINKPAD_MAH,
+ &battery->flags) &&
+ battery->design_voltage) {
+ battery->design_capacity =
+ battery->design_capacity *
+ 10000 / battery->design_voltage;
+ battery->full_charge_capacity =
+ battery->full_charge_capacity *
+ 10000 / battery->design_voltage;
+ battery->design_capacity_warning =
+ battery->design_capacity_warning *
+ 10000 / battery->design_voltage;
+ battery->capacity_now = battery->capacity_now *
+ 10000 / battery->design_voltage;
+ }
+ }
+ }
}
static int acpi_battery_update(struct acpi_battery *battery)