power: remove POWER_SUPPLY_PROP_CAPACITY_LEVEL

The CAPACITY_LEVEL stuff defines various levels of charge; however, what
is the difference between them?  What differentiates between HIGH and NORMAL,
LOW and CRITICAL, etc?

As it appears that these are fairly arbitrary, we end up making such policy
decisions in the kernel (or in hardware).  This is the sort of decision that
should be made in userspace, not in the kernel.

If the hardware does not support _CAPACITY and it cannot be easily calculated,
then perhaps the driver should register a custom CAPACITY_LEVEL attribute;
however, userspace should not become accustomed to looking for such a thing,
and we should certainly not encourage drivers to provide CAPACITY_LEVEL
stubs.

The following removes support for POWER_SUPPLY_PROP_CAPACITY_LEVEL.  The
OLPC battery driver is the only driver making use of this, so it's
removed from there as well.

Signed-off-by: Andres Salomon <dilinger@debian.org>
Signed-off-by: David Woodhouse <dwmw2@infradead.org>

1 files changed, 0 insertions, 2 deletions

diff --git a/Documentation/power_supply_class.txt b/Documentation/power_supply_class.txt
index 9758cf433c06..a032c316b3bc 100644
--- a/Documentation/power_supply_class.txt
+++ b/Documentation/power_supply_class.txt
@@ -100,8 +100,6 @@ age)". I.e. these attributes represents real thresholds, not design values.
 ENERGY_FULL, ENERGY_EMPTY - same as above but for energy.
 
 CAPACITY - capacity in percents.
-CAPACITY_LEVEL - capacity level. This corresponds to
-POWER_SUPPLY_CAPACITY_LEVEL_*.
 
 TEMP - temperature of the power supply.
 TEMP_AMBIENT - ambient temperature.