power_supply: Add a charge_type property, and use it for olpc driver

This adds a new sysfs file called 'charge_type' which displays the
type of charging (unknown, n/a, trickle charge, or fast charging).

This allows things like battery diagnostics to determine what the
battery/EC is doing without resorting to changing the 'status' sysfs
output.

Signed-off-by: Andres Salomon <dilinger@collabora.co.uk>
Acked-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Signed-off-by: Anton Vorontsov <cbouatmailru@gmail.com>

1 files changed, 5 insertions, 0 deletions

diff --git a/Documentation/power/power_supply_class.txt b/Documentation/power/power_supply_class.txt
index 709d95571d7b..9f16c5178b66 100644
--- a/Documentation/power/power_supply_class.txt
+++ b/Documentation/power/power_supply_class.txt
@@ -76,6 +76,11 @@ STATUS - this attribute represents operating status (charging, full,
 discharging (i.e. powering a load), etc.). This corresponds to
 BATTERY_STATUS_* values, as defined in battery.h.
 
+CHARGE_TYPE - batteries can typically charge at different rates.
+This defines trickle and fast charges.  For batteries that
+are already charged or discharging, 'n/a' can be displayed (or
+'unknown', if the status is not known).
+
 HEALTH - represents health of the battery, values corresponds to
 POWER_SUPPLY_HEALTH_*, defined in battery.h.