/* * Copyright (c) 2006-2021, RT-Thread Development Team * * SPDX-License-Identifier: Apache-2.0 * * Change Logs: * Date Author Notes */ #ifndef __VBUS_API_H__ #define __VBUS_API_H__ #define RT_VBUS_USING_FLOW_CONTROL #define RT_VBUS_CHANNEL_NR 32 #define RT_VBUS_BLK_HEAD_SZ 4 #define RT_VBUS_MAX_PKT_SZ (256 - RT_VBUS_BLK_HEAD_SZ) #define RT_VMM_RB_BLK_NR (_RT_VBUS_RING_SZ / 64 - 1) #ifndef __ASSEMBLY__ #include <stddef.h> /* For size_t */ struct rt_vbus_blk { unsigned char id; unsigned char qos; unsigned char len; unsigned char reserved; unsigned char data[60]; } __attribute__((packed)); struct rt_vbus_ring { volatile size_t put_idx; volatile size_t get_idx; /* whether the writer is blocked on this ring. For RTT, it means the * central writer thread is waiting. For Linux, it means there are some * threads waiting for space to write. * * Note that we don't record whether there are reading thread blocked. When * there is new data, the other side will always be waked up. */ volatile unsigned int blocked; struct rt_vbus_blk blks[RT_VMM_RB_BLK_NR]; }; enum { RT_VBUS_CHN0_CMD_ENABLE, RT_VBUS_CHN0_CMD_DISABLE, RT_VBUS_CHN0_CMD_SET, RT_VBUS_CHN0_CMD_ACK, RT_VBUS_CHN0_CMD_NAK, /* If the recieving side reached high water mark. It has the right to * suspend the channel. All the server/client should know about this * command but the one that does not implement flow control could ignore * this command. */ RT_VBUS_CHN0_CMD_SUSPEND, RT_VBUS_CHN0_CMD_RESUME, RT_VBUS_CHN0_CMD_MAX, }; enum rt_vbus_chn_status { /* initial state, available for reuse */ RT_VBUS_CHN_ST_AVAILABLE, /* ACK DISABLE send(CS) or received(CS), but not ready for reuse.(the * channel is not closed by this end) */ RT_VBUS_CHN_ST_CLOSED, /* ENABLE send(client) or received(server) */ RT_VBUS_CHN_ST_ESTABLISHING, /* ACK SET send(C) or received(S) */ RT_VBUS_CHN_ST_ESTABLISHED, /* Channel suspended by flow control. */ RT_VBUS_CHN_ST_SUSPEND, /* DISABLE received(CS) */ RT_VBUS_CHN_ST_CLOSING, }; #endif #undef BUILD_ASSERT /* borrowed from http://lxr.linux.no/linux+v2.6.26.5/include/linux/kernel.h#L494 */ #define BUILD_ASSERT(condition) ((void)sizeof(char[1 - 2*!(condition)])) /* max length of a channel name, including the \0 */ #define RT_VBUS_CHN_NAME_MAX 16 #endif /* end of include guard: __VBUS_API_H__ */