[PATCH] HID: logitech-hidpp: BatteryVoltage: only read chargeStatus if extPower is active

From: Filipe LaÃns
Date: Sat Jan 11 2020 - 14:47:48 EST


In the HID++ 2.0 function getBatteryInfo() from the BatteryVoltage
(0x1001) feature, chargeStatus is only valid if extPower is active.

Previously we were ignoring extPower, which resulted in wrong values.

Example:
With an unplugged mouse

$ cat /sys/class/power_supply/hidpp_battery_0/status
Charging

This patch makes fixes that, it also renames charge_sts to flags as
charge_sts can be confused with chargeStatus from the spec.

Spec:
+--------+-------------------------------------------------------------------------+
| byte | 2 |
+--------+--------------+------------+------------+----------+----------+----------+
| bit | 0..2 | 3 | 4 | 5 | 6 | 7 |
+--------+--------------+------------+------------+----------+----------+----------+
| buffer | chargeStatus | fastCharge | slowCharge | critical | (unused) | extPower |
+--------+--------------+------------+------------+----------+----------+----------+
Table 1 - battery voltage (0x1001), getBatteryInfo() (ASE 0), 3rd byte

+-------+--------------------------------------+
| value | meaning |
+-------+--------------------------------------+
| 0 | Charging |
+-------+--------------------------------------+
| 1 | End of charge (100% charged) |
+-------+--------------------------------------+
| 2 | Charge stopped (any "normal" reason) |
+-------+--------------------------------------+
| 7 | Hardware error |
+-------+--------------------------------------+
Table 2 - chargeStatus value

Signed-off-by: Filipe LaÃns <lains@xxxxxxxxxxxxx>
---
drivers/hid/hid-logitech-hidpp.c | 43 ++++++++++++++++----------------
1 file changed, 21 insertions(+), 22 deletions(-)

diff --git a/drivers/hid/hid-logitech-hidpp.c b/drivers/hid/hid-logitech-hidpp.c
index bb063e7d48df..39a5ee0aaab0 100644
--- a/drivers/hid/hid-logitech-hidpp.c
+++ b/drivers/hid/hid-logitech-hidpp.c
@@ -1256,36 +1256,35 @@ static int hidpp20_battery_map_status_voltage(u8 data[3], int *voltage,
{
int status;

- long charge_sts = (long)data[2];
+ long flags = (long) data[2];

- *level = POWER_SUPPLY_CAPACITY_LEVEL_UNKNOWN;
- switch (data[2] & 0xe0) {
- case 0x00:
- status = POWER_SUPPLY_STATUS_CHARGING;
- break;
- case 0x20:
- status = POWER_SUPPLY_STATUS_FULL;
- *level = POWER_SUPPLY_CAPACITY_LEVEL_FULL;
- break;
- case 0x40:
+ if (flags & 0x80)
+ switch (flags & 0x07) {
+ case 0:
+ status = POWER_SUPPLY_STATUS_CHARGING;
+ break;
+ case 1:
+ status = POWER_SUPPLY_STATUS_FULL;
+ *level = POWER_SUPPLY_CAPACITY_LEVEL_FULL;
+ break;
+ case 2:
+ status = POWER_SUPPLY_STATUS_NOT_CHARGING;
+ break;
+ default:
+ status = POWER_SUPPLY_STATUS_UNKNOWN;
+ break;
+ }
+ else
status = POWER_SUPPLY_STATUS_DISCHARGING;
- break;
- case 0xe0:
- status = POWER_SUPPLY_STATUS_NOT_CHARGING;
- break;
- default:
- status = POWER_SUPPLY_STATUS_UNKNOWN;
- }

*charge_type = POWER_SUPPLY_CHARGE_TYPE_STANDARD;
- if (test_bit(3, &charge_sts)) {
+ if (test_bit(3, &flags)) {
*charge_type = POWER_SUPPLY_CHARGE_TYPE_FAST;
}
- if (test_bit(4, &charge_sts)) {
+ if (test_bit(4, &flags)) {
*charge_type = POWER_SUPPLY_CHARGE_TYPE_TRICKLE;
}
-
- if (test_bit(5, &charge_sts)) {
+ if (test_bit(5, &flags)) {
*level = POWER_SUPPLY_CAPACITY_LEVEL_CRITICAL;
}

--
2.24.1