[PATCH v2 0/5] power: supply: axp20x_usb_power: cleanup input current limit handling

[Aren Moynihan <aren@peacevolution.org>]

Proper handling of the input current limit will be necessary to
implement usb power delivery on the Pine64 PinePhone. The PinePhone has
a separate chip (anx7688) that handles usb power delivery (among other
things), so we will need a way to apply the current limit which that
negotiates.

The new logic to get/set the input current limit, and get the usb type
is originally based on code Ondřej Jirman wrote[1], but I have
significantly refactored it.

While working on this, I also discovered that the axp803 pmic sets a
current limit of 3A on the usb port without any negotiation if it
doesn't detect a battery.

v1 of this patch can be found at:
https://lore.kernel.org/lkml/20240121014057.1042466-1-aren@peacevolution.org/

1: https://xff.cz/git/linux/commit/?h=axp-6.7&id=3dcd33dfd1ae58db159427365dcb6d0d2b12f06d

Changes in v2:
 - Values less than the lowest supported limit are rounded up instead
   of returning -EINVAL when setting the input current limit.
 - Rename existing current_max logic to input_current_limit. This also
   makes it possible to reuse some of that logic.
 - Split current limit register and bc race condition fixes into
   different commits.

Aren Moynihan (5):
  power: supply: axp20x_usb_power: replace current_max with
    input_current_limit
  power: supply: axp20x_usb_power: use correct register for input
    current limit
  power: supply: axp20x_usb_power: fix race condition with usb bc
  power: supply: axp20x_usb_power: enable usb_type reporting
  power: supply: axp20x_usb_power: set input current limit in probe

 drivers/power/supply/axp20x_usb_power.c | 160 +++++++++++++++++++++---
 1 file changed, 144 insertions(+), 16 deletions(-)

-- 
2.43.0