diff options
Diffstat (limited to 'board/servo_v4p1/usb_sm.c')
| -rw-r--r-- | board/servo_v4p1/usb_sm.c | 193 |
1 files changed, 0 insertions, 193 deletions
diff --git a/board/servo_v4p1/usb_sm.c b/board/servo_v4p1/usb_sm.c deleted file mode 100644 index 94b5e0c08d..0000000000 --- a/board/servo_v4p1/usb_sm.c +++ /dev/null @@ -1,193 +0,0 @@ -/* Copyright 2020 The Chromium OS Authors. All rights reserved. - * Use of this source code is governed by a BSD-style license that can be - * found in the LICENSE file. - */ - -#include "common.h" -#include "console.h" -#include "stdbool.h" -#include "usb_pd.h" -#include "usb_sm.h" -#include "util.h" - -#ifdef CONFIG_COMMON_RUNTIME -#define CPRINTF(format, args...) cprintf(CC_USB, format, ## args) -#define CPRINTS(format, args...) cprints(CC_USB, format, ## args) -#else /* CONFIG_COMMON_RUNTIME */ -#define CPRINTF(format, args...) -#define CPRINTS(format, args...) -#endif - -/* Private structure (to this file) used to track state machine context */ -struct internal_ctx { - usb_state_ptr last_entered; - uint32_t running : 1; - uint32_t enter : 1; - uint32_t exit : 1; -}; -BUILD_ASSERT(sizeof(struct internal_ctx) == - member_size(struct sm_ctx, internal)); - -/* Gets the first shared parent state between a and b (inclusive) */ -static usb_state_ptr shared_parent_state(usb_state_ptr a, usb_state_ptr b) -{ - const usb_state_ptr orig_b = b; - - /* There are no common ancestors */ - if (b == NULL) - return NULL; - - /* This assumes that both A and B are NULL terminated without cycles */ - while (a != NULL) { - /* We found a match return */ - if (a == b) - return a; - - /* - * Otherwise, increment b down the list for comparison until we - * run out, then increment a and start over on b for comparison - */ - if (b->parent == NULL) { - a = a->parent; - b = orig_b; - } else { - b = b->parent; - } - } - - return NULL; -} - -/* - * Call all entry functions of parents before children. If set_state is called - * during one of the entry functions, then do not call any remaining entry - * functions. - */ -static void call_entry_functions(const int port, - struct internal_ctx *const internal, - const usb_state_ptr stop, - const usb_state_ptr current) -{ - if (current == stop) - return; - - call_entry_functions(port, internal, stop, current->parent); - - /* - * If the previous entry function called set_state, then don't enter - * remaining states. - */ - if (!internal->enter) - return; - - /* Track the latest state that was entered, so we can exit properly. */ - internal->last_entered = current; - if (current->entry) - current->entry(port); -} - -/* - * Call all exit functions of children before parents. Note set_state is ignored - * during an exit function. - */ -static void call_exit_functions(const int port, const usb_state_ptr stop, - const usb_state_ptr current) -{ - if (current == stop) - return; - - if (current->exit) - current->exit(port); - - call_exit_functions(port, stop, current->parent); -} - -void set_state(const int port, struct sm_ctx *const ctx, - const usb_state_ptr new_state) -{ - struct internal_ctx * const internal = (void *) ctx->internal; - usb_state_ptr last_state; - usb_state_ptr shared_parent; - - /* - * It does not make sense to call set_state in an exit phase of a state - * since we are already in a transition; we would always ignore the - * intended state to transition into. - */ - if (internal->exit) { - CPRINTF("C%d: Ignoring set state to 0x%pP within 0x%pP", - port, new_state, ctx->current); - return; - } - - /* - * Determine the last state that was entered. Normally it is current, - * but we could have called set_state within an entry phase, so we - * shouldn't exit any states that weren't fully entered. - */ - last_state = internal->enter ? internal->last_entered : ctx->current; - - /* We don't exit and re-enter shared parent states */ - shared_parent = shared_parent_state(last_state, new_state); - - /* - * Exit all of the non-common states from the last state. - */ - internal->exit = true; - call_exit_functions(port, shared_parent, last_state); - internal->exit = false; - - ctx->previous = ctx->current; - ctx->current = new_state; - - /* - * Enter all new non-common states. last_entered will contain the last - * state that successfully entered before another set_state was called. - */ - internal->last_entered = NULL; - internal->enter = true; - call_entry_functions(port, internal, shared_parent, ctx->current); - /* - * Setting enter to false ensures that all pending entry calls will be - * skipped (in the case of a parent state calling set_state, which means - * we should not enter any child states) - */ - internal->enter = false; - - /* - * If we set_state while we are running a child state, then stop running - * any remaining parent states. - */ - internal->running = false; -} - -/* - * Call all run functions of children before parents. If set_state is called - * during one of the entry functions, then do not call any remaining entry - * functions. - */ -static void call_run_functions(const int port, - const struct internal_ctx *const internal, - const usb_state_ptr current) -{ - if (!current) - return; - - /* If set_state is called during run, don't call remain functions. */ - if (!internal->running) - return; - - if (current->run) - current->run(port); - - call_run_functions(port, internal, current->parent); -} - -void run_state(const int port, struct sm_ctx *const ctx) -{ - struct internal_ctx * const internal = (void *) ctx->internal; - - internal->running = true; - call_run_functions(port, internal, ctx->current); - internal->running = false; -} |