zephyr/drivers/simple/uart.c

120 lines
3.3 KiB
C

/*! @file
* @brief Simple UART driver
*
* A simple UART driver allowing application to handle all aspects of received
* protocol data.
*/
/*
* Copyright (c) 2015 Intel Corporation
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are met:
*
* 1) Redistributions of source code must retain the above copyright notice,
* this list of conditions and the following disclaimer.
*
* 2) Redistributions in binary form must reproduce the above copyright notice,
* this list of conditions and the following disclaimer in the documentation
* and/or other materials provided with the distribution.
*
* 3) Neither the name of Intel Corporation nor the names of its contributors
* may be used to endorse or promote products derived from this software without
* specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
* AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE
* LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
* CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
* SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
* INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
* CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
* POSSIBILITY OF SUCH DAMAGE.
*/
#include <nanokernel.h>
#include <arch/cpu.h>
#include <board.h>
#include <drivers/uart.h>
#include <simple/uart.h>
#include <misc/printk.h>
#define UART CONFIG_UART_SIMPLE_INDEX
static uint8_t *recv_buf;
static size_t recv_buf_len;
static uart_simple_recv_cb app_cb;
static size_t recv_off;
void uart_simple_isr(void *unused)
{
ARG_UNUSED(unused);
while (uart_irq_update(UART) && uart_irq_is_pending(UART)) {
int rx;
if (!uart_irq_rx_ready(UART)) {
continue;
}
rx = uart_fifo_read(UART, recv_buf + recv_off,
recv_buf_len - recv_off);
if (!rx) {
continue;
}
/* Call application callback with received data. Application
* may provide new buffer or alter data offset.
*/
recv_off += rx;
recv_buf = app_cb(recv_buf, &recv_off);
}
}
int uart_simple_send(const uint8_t *data, int len)
{
return uart_fifo_fill(UART, data, len);
}
IRQ_CONNECT_STATIC(uart_simple, CONFIG_UART_SIMPLE_IRQ,
CONFIG_UART_SIMPLE_INT_PRI, uart_simple_isr, 0);
static void uart_simple_setup(int uart, struct uart_init_info *info)
{
uart_init(uart, info);
uart_irq_rx_disable(uart);
uart_irq_tx_disable(uart);
IRQ_CONFIG(uart_simple, uart_irq_get(uart));
irq_enable(uart_irq_get(uart));
/* Drain the fifo */
while (uart_irq_rx_ready(uart)) {
unsigned char c;
uart_fifo_read(uart, &c, 1);
}
uart_irq_rx_enable(uart);
}
void uart_simple_register(uint8_t *buf, size_t len, uart_simple_recv_cb cb)
{
struct uart_init_info info = {
.options = 0,
.sys_clk_freq = CONFIG_UART_SIMPLE_FREQ,
.baud_rate = CONFIG_UART_SIMPLE_BAUDRATE,
.int_pri = CONFIG_UART_SIMPLE_INT_PRI,
};
recv_buf = buf;
recv_buf_len = len;
app_cb = cb;
uart_simple_setup(UART, &info);
}