/**
* \file
* <!--
* This file is part of BeRTOS.
*
* Bertos is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
*
* As a special exception, you may use this file as part of a free software
* library without restriction. Specifically, if other files instantiate
* templates or use macros or inline functions from this file, or you compile
* this file and link it with other files to produce an executable, this
* file does not by itself cause the resulting executable to be covered by
* the GNU General Public License. This exception does not however
* invalidate any other reasons why the executable file might be covered by
* the GNU General Public License.
*
* Copyright 2007 Develer S.r.l. (http://www.develer.com/)
* -->
*
* \brief pocketBus protocol Command layer implementation.
*
* This module implements command layer over pocketBus
* protocol.
* Payload packets received by pocketBus are first checked for
* address matching.
* If a packet is addressed to us we look for a suitable
* callback function to call.
*
* The received payload format is as follows:
* <pre>
* +----------------------------------------+
* | CMD | DATA |
* +----------------------------------------+
* | | |
* + 2B + 0..N Byte +
* </pre>
*
* The CMD ID used is the same supplied by the master when
* the command was sent.
*
* \author Francesco Sacchi <batt@develer.com>
*/
#include "pocketcmd.h"
#include "pocketbus.h"
#include "cfg/cfg_pocketbus.h"
// Define logging setting (for cfg/log.h module).
#define LOG_LEVEL POCKETBUS_LOG_LEVEL
#define LOG_VERBOSITY POCKETBUS_LOG_FORMAT
#include <cfg/log.h>
#include <cfg/debug.h>
#include <cfg/macros.h>
#include <cfg/module.h>
#include <drv/timer.h>
#include <cpu/byteorder.h>
#include <cpu/detect.h>
#include <string.h>
/**
* pocketBus Command poll function.
* Call it to read and process pocketBus commands.
*/
void pocketcmd_poll(struct PocketCmdCtx *ctx)
{
PocketCmdMsg msg;
while (pocketcmd_recv(ctx, &msg))
{
/* Check for command callback */
pocketcmd_hook_t callback = ctx->search(msg.cmd);
/* Call it if exists */
if (callback)
callback(&msg);
}
}
/**
* pocketBus Command recv function.
* Call it to read and process pocketBus commands.
*/
bool pocketcmd_recv(struct PocketCmdCtx *ctx, PocketCmdMsg *recv_msg)
{
PocketMsg msg;
/* Try to read a packet from pocketBus */
while (pocketbus_recv(ctx->bus_ctx, &msg))
{
/* Check address */
if (msg.addr == ctx->addr ||
msg.addr == POCKETBUS_BROADCAST_ADDR)
{
#if CPU_AVR
const PocketCmdHdr *hdr = (const PocketCmdHdr *)msg.payload;
#else
#if !CPU_ARM
#warning Fix alignment problem..
/*
* The code below make one memcopy, this the only way to
* solve alignment problem on ARM. If you are use other
* architecture you should find other way to optimize
* this code.
*/
#endif
PocketCmdHdr hd;
memcpy(&hd, msg.payload, sizeof(PocketCmdHdr));
const PocketCmdHdr *hdr = &hd;
#endif
pocketcmd_t cmd = be16_to_cpu(hdr->cmd);
/* We're no longer waiting for a reply (in case we were) */
if (cmd == ctx->waiting)
ctx->waiting = PKTCMD_NULL;
recv_msg->cmd_ctx = ctx;
recv_msg->cmd = cmd;
recv_msg->len = msg.len - sizeof(PocketCmdHdr);
recv_msg->buf = msg.payload + sizeof(PocketCmdHdr);
return true;
}
}
return false;
}
/**
* Send command \a cmd to/from slave adding \a len arguments in \a buf.
* Address used is contained in \a ctx->addr .
* If we are master and the message has a reply, you must set \a wait_reply to true.
* \return true if all is ok, false if we are already waiting a replay from another slave.
*/
bool pocketcmd_send(struct PocketCmdCtx *ctx, pocketcmd_t cmd, const void *buf, size_t len, bool wait_reply)
{
/* Check if we are waiting a reply from someone */
if (ctx->waiting != PKTCMD_NULL)
{
/* Check is reply timeout is elapsed */
if (timer_clock() - ctx->reply_timer < ms_to_ticks(CONFIG_POCKETBUS_CMD_REPLY_TIMEOUT))
{
LOG_ERR("Pkt discard! waiting cmd[%04X]\n", ctx->waiting);
return false;
}
else
{
LOG_INFO("Timeout waiting cmd[%04X]\n", ctx->waiting);
ctx->waiting = PKTCMD_NULL;
}
}
/* Endianess! */
cmd = cpu_to_be16(cmd);
/* Send packet */
pocketbus_begin(ctx->bus_ctx, ctx->addr);
pocketbus_write(ctx->bus_ctx, &cmd, sizeof(cmd));
pocketbus_write(ctx->bus_ctx, buf, len);
pocketbus_end(ctx->bus_ctx);
if (wait_reply)
{
ctx->waiting = be16_to_cpu(cmd);
ctx->reply_timer = timer_clock();
}
return true;
}
/**
* Init pocketBus command layer.
* \a ctx is pocketBus command layer context.
* \a bus_ctx is pocketBus context.
* \a addr is slave address (see pocketcmd_setAddr for details.)
* \a search is the lookup function used to search command ID callbacks.
*/
void pocketcmd_init(struct PocketCmdCtx *ctx, struct PocketBusCtx *bus_ctx, pocketbus_addr_t addr, pocketcmd_lookup_t search)
{
ASSERT(ctx);
ASSERT(bus_ctx);
ASSERT(search);
MOD_CHECK(timer);
memset(ctx, 0, sizeof(*ctx));
ctx->bus_ctx = bus_ctx;
ctx->search = search;
pocketcmd_setAddr(ctx, addr);
}
/**
* Helper function used to reply to master with an ACK.
*/
void pocketcmd_replyAck(struct PocketCmdMsg *msg)
{
uint8_t ack[] = { POCKETBUS_ACK };
pocketcmd_slaveReply(msg->cmd_ctx, msg->cmd, ack, sizeof(ack));
}
/**
* Helper function used to reply to master with a NAK.
*/
void pocketcmd_replyNak(struct PocketCmdMsg *msg)
{
uint8_t nak[] = { POCKETBUS_NAK };
pocketcmd_slaveReply(msg->cmd_ctx, msg->cmd, nak, sizeof(nak));
}