Files
OpenCellular/include/queue.h
Louis Yung-Chieh Lo 210ddfefcf Refactor the i8042 module to be thread-safe.
Any command/data coming from host will be placed in from_host queue, and
the interrupt handler returns immediately. The i8042_command_task() will
handle them later.

Data reply to the host will be protected by the mutex.

BUG=chrome-os-partner:10090
TEST=randomly play around on the link board.

Change-Id: Ic19d5abd1abf8dc261ddaad4224cd9305c2f36a4
Signed-off-by: Louis Yung-Chieh Lo <yjlou@chromium.org>
Reviewed-on: https://gerrit.chromium.org/gerrit/24299
Commit-Ready: Yung-Chieh Lo <yjlou%chromium.org@gtempaccount.com>
Reviewed-by: Yung-Chieh Lo <yjlou%chromium.org@gtempaccount.com>
Tested-by: Yung-Chieh Lo <yjlou%chromium.org@gtempaccount.com>
2012-06-07 20:48:51 -07:00

41 lines
1.0 KiB
C

/* Copyright (c) 2012 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.
*
* Queue data structure.
*/
#include "common.h"
/* Generic queue container.
*
* head: next to dequeqe
* tail: next to enqueue
*
* Empty:
* head == tail
* Full:
* ((tail + 1) % buf_bytes) == head
*/
struct queue {
int head, tail;
int buf_bytes; /* size of buffer (in byte) */
int unit_bytes; /* size of unit (in byte) */
uint8_t *buf;
};
/* Reset the queue to empty state. */
void queue_reset(struct queue *queue);
/* Return TRUE if the queue is empty. */
int queue_is_empty(const struct queue *q);
/* Return TRUE if the queue has at least one unit space. */
int queue_has_space(const struct queue *q, int unit_count);
/* Add multiple units into queue. */
void queue_add_units(struct queue *q, const void *src, int unit_count);
/* Remove one unit from the begin of the queue. */
int queue_remove_unit(struct queue *q, void *dest);