From 72357cd1edf885e559dbb715b33cfb861a0a3265 Mon Sep 17 00:00:00 2001 From: Alec Berg Date: Wed, 28 May 2014 18:10:25 -0700 Subject: samus: Allow samus to charge w/o battery or with dead battery Use a EC to PD host command to notify the PD MCU when a battery is present and charged enough that it is ok to negotiate for a higher power. The PD MCU will not negotiate until the host command is received, which allows the system to be powered without a battery or with a dead battery with 5V. BUG=chrome-os-partner:28611 BRANCH=none TEST=Tested on a samus: 1) Tested the normal case of battery charged and plugged in. When charger is plugged in, the device immediately starts negotiating for 20V and starts charging. 2) Tested with no battery. Plug in a charger, samus boots and stays alive. VBUS measured at 5V. When a battery is plugged in, device negotiates for 20V and starts charging. 3) Tested dead battery by taking a battery with no charge, and plugging in zinger. Everything boots, but PD does not negotiate for power. Then when battery reaches 1%, PD negotiates and zinger switches to 20V without causing a reboot. Change-Id: Iaa451403674e86cddbd3fe80e9503584910be576 Signed-off-by: Alec Berg Reviewed-on: https://chromium-review.googlesource.com/201958 Reviewed-by: Vincent Palatin --- include/host_command.h | 6 ++++++ 1 file changed, 6 insertions(+) (limited to 'include/host_command.h') diff --git a/include/host_command.h b/include/host_command.h index 1fbf0b6554..231ef9a6b8 100644 --- a/include/host_command.h +++ b/include/host_command.h @@ -207,6 +207,12 @@ void host_packet_receive(struct host_packet *pkt); */ void host_throttle_cpu(int throttle); + +/** + * Signal host command task to send status to PD MCU. + */ +void host_command_pd_send_status(void); + /** * Send host command to PD MCU. * -- cgit v1.2.1