charge_manager: Support multiple independent charge ceilings

We will soon have a need to independently set a charge ceiling from both
the PD state machine and from incoming host commands. Store these
ceilings separately, and have the minimum take effect.

BUG=chrome-os-partner:43285
TEST=Pass unit tests. Also, host command current limit takes effect with
subsequent commit.
BRANCH=None

Change-Id: I0ecfe888a7df0d5da5a68999c164c7c841da348b
Signed-off-by: Shawn Nematbakhsh <shawnn@chromium.org>
Reviewed-on: https://chromium-review.googlesource.com/293818
Reviewed-by: Alec Berg <alecaberg@chromium.org>

1 files changed, 15 insertions, 2 deletions

diff --git a/include/charge_manager.h b/include/charge_manager.h
index 8758c3a19c..6cfd6cc7ce 100644
--- a/include/charge_manager.h
+++ b/include/charge_manager.h
@@ -51,8 +51,21 @@ enum dualrole_capabilities {
 /* Called by charging tasks to indicate partner dualrole capability change */
 void charge_manager_update_dualrole(int port, enum dualrole_capabilities cap);
 
-/* Update charge ceiling for a given port */
-void charge_manager_set_ceil(int port, int ceil);
+/*
+ * Charge ceiling can be set independently by different tasks / functions,
+ * for different purposes.
+ */
+enum ceil_requestor {
+	/* Set by PD task, during negotiation */
+	CEIL_REQUESTOR_PD,
+	/* Set by host commands */
+	CEIL_REQUESTOR_HOST,
+	/* Number of ceiling groups */
+	CEIL_REQUESTOR_COUNT,
+};
+
+/* Update charge ceiling for a given port / requestor */
+void charge_manager_set_ceil(int port, enum ceil_requestor requestor, int ceil);
 
 /* Select an 'override port', which is always the preferred charge port */
 int charge_manager_set_override(int port);