blob: 47e74dc4f3724a5988805bbb54b99f59e970a3e1 [file] [log] [blame]
/*
* Copyright (c) 2022, Commonwealth Scientific and Industrial Research
* Organisation (CSIRO) ABN 41 687 119 230.
*
* SPDX-License-Identifier: Apache-2.0
*/
#include <zephyr/logging/log.h>
#include <zephyr/kernel.h>
#include <zephyr/drivers/uart.h>
#include "modem_context.h"
#include "modem_iface_uart.h"
LOG_MODULE_REGISTER(modem_iface_uart_async, CONFIG_MODEM_LOG_LEVEL);
#define RX_BUFFER_SIZE CONFIG_MODEM_IFACE_UART_ASYNC_RX_BUFFER_SIZE
#define RX_BUFFER_NUM CONFIG_MODEM_IFACE_UART_ASYNC_RX_NUM_BUFFERS
K_MEM_SLAB_DEFINE(uart_modem_async_rx_slab, RX_BUFFER_SIZE, RX_BUFFER_NUM, 1);
static void iface_uart_async_callback(const struct device *dev,
struct uart_event *evt,
void *user_data)
{
struct modem_iface *iface = user_data;
struct modem_iface_uart_data *data = iface->iface_data;
uint32_t written;
void *buf;
int rc;
switch (evt->type) {
case UART_TX_DONE:
k_sem_give(&data->tx_sem);
break;
case UART_RX_BUF_REQUEST:
/* Allocate next RX buffer for UART driver */
rc = k_mem_slab_alloc(&uart_modem_async_rx_slab, (void **)&buf, K_NO_WAIT);
if (rc < 0) {
/* Major problems, UART_RX_BUF_RELEASED event is not being generated, or
* CONFIG_MODEM_IFACE_UART_ASYNC_RX_NUM_BUFFERS is not large enough.
*/
LOG_ERR("RX buffer starvation");
break;
}
/* Provide the buffer to the UART driver */
uart_rx_buf_rsp(dev, buf, RX_BUFFER_SIZE);
break;
case UART_RX_BUF_RELEASED:
/* UART driver is done with memory, free it */
k_mem_slab_free(&uart_modem_async_rx_slab, (void *)evt->data.rx_buf.buf);
break;
case UART_RX_RDY:
/* Place received data on the ring buffer */
written = ring_buf_put(&data->rx_rb,
evt->data.rx.buf + evt->data.rx.offset,
evt->data.rx.len);
if (written != evt->data.rx.len) {
LOG_WRN("Received bytes dropped from ring buf");
}
/* Notify upper layer that new data has arrived */
k_sem_give(&data->rx_sem);
break;
case UART_RX_STOPPED:
break;
case UART_RX_DISABLED:
/* RX stopped (likely due to line error), re-enable it */
rc = k_mem_slab_alloc(&uart_modem_async_rx_slab, (void **)&buf, K_FOREVER);
if (rc < 0) {
LOG_ERR("RX disabled and buffer starvation");
break;
}
rc = uart_rx_enable(dev, buf, RX_BUFFER_SIZE,
CONFIG_MODEM_IFACE_UART_ASYNC_RX_TIMEOUT_US);
if (rc < 0) {
LOG_ERR("Failed to re-enable UART");
}
break;
default:
break;
}
}
static int modem_iface_uart_async_read(struct modem_iface *iface,
uint8_t *buf, size_t size, size_t *bytes_read)
{
struct modem_iface_uart_data *data;
if (!iface || !iface->iface_data) {
return -EINVAL;
}
if (size == 0) {
*bytes_read = 0;
return 0;
}
/* Pull data off the ring buffer */
data = iface->iface_data;
*bytes_read = ring_buf_get(&data->rx_rb, buf, size);
return 0;
}
static int modem_iface_uart_async_write(struct modem_iface *iface,
const uint8_t *buf, size_t size)
{
struct modem_iface_uart_data *data;
int rc;
if (!iface || !iface->iface_data) {
return -EINVAL;
}
if (size == 0) {
return 0;
}
/* Start the transmission */
rc = uart_tx(iface->dev, buf, size, SYS_FOREVER_MS);
if (rc >= 0) {
/* Wait until the transmission completes */
data = iface->iface_data;
k_sem_take(&data->tx_sem, K_FOREVER);
}
return rc;
}
int modem_iface_uart_init_dev(struct modem_iface *iface,
const struct device *dev)
{
struct modem_iface_uart_data *data;
void *buf;
int rc;
if (!device_is_ready(dev)) {
return -ENODEV;
}
/* Check if there's already a device inited to this iface. If so,
* interrupts needs to be disabled on that too before switching to avoid
* race conditions with modem_iface_uart_isr.
*/
if (iface->dev) {
LOG_WRN("Device %s already inited", iface->dev->name);
uart_rx_disable(iface->dev);
}
iface->dev = dev;
data = iface->iface_data;
/* Configure async UART callback */
rc = uart_callback_set(dev, iface_uart_async_callback, iface);
if (rc < 0) {
LOG_ERR("Failed to set UART callback");
return rc;
}
/* Enable reception permanently on the interface */
k_mem_slab_alloc(&uart_modem_async_rx_slab, (void **)&buf, K_FOREVER);
rc = uart_rx_enable(dev, buf, RX_BUFFER_SIZE, CONFIG_MODEM_IFACE_UART_ASYNC_RX_TIMEOUT_US);
if (rc < 0) {
LOG_ERR("Failed to enable UART RX");
}
return rc;
}
int modem_iface_uart_init(struct modem_iface *iface, struct modem_iface_uart_data *data,
const struct modem_iface_uart_config *config)
{
int ret;
if (iface == NULL || data == NULL || config == NULL) {
return -EINVAL;
}
iface->iface_data = data;
iface->read = modem_iface_uart_async_read;
iface->write = modem_iface_uart_async_write;
ring_buf_init(&data->rx_rb, config->rx_rb_buf_len, config->rx_rb_buf);
k_sem_init(&data->rx_sem, 0, 1);
k_sem_init(&data->tx_sem, 0, 1);
/* Configure hardware flow control */
data->hw_flow_control = config->hw_flow_control;
/* Get UART device */
ret = modem_iface_uart_init_dev(iface, config->dev);
if (ret < 0) {
iface->iface_data = NULL;
iface->read = NULL;
iface->write = NULL;
return ret;
}
return 0;
}