/** * @brief UART Driver for interacting with host serial ports * * @note Driver can open and send characters to the host serial ports (such as /dev/ttyUSB0 or * /dev/ttyACM0). Only polling Uart API is implemented. Driver can be configured via devicetree, * command line options or at runtime. * * To learn more see Native TTY section at: * https://docs.zephyrproject.org/latest/boards/posix/native_posix/doc/index.html * or * ${ZEPHYR_BASE}/boards/posix/native_posix/doc/index.rst * * Copyright (c) 2023 Marko Sagadin * SPDX-License-Identifier: Apache-2.0 */ #include #include #include #include #include "cmdline.h" #include "posix_native_task.h" #include "uart_native_tty_bottom.h" #include "nsi_host_trampolines.h" #define WARN(...) nsi_print_warning(__VA_ARGS__) #define ERROR(...) nsi_print_error_and_exit(__VA_ARGS__) #define DT_DRV_COMPAT zephyr_native_tty_uart struct native_tty_data { /* File descriptor used for the tty device. */ int fd; /* Absolute path to the tty device. */ char *serial_port; /* Baudrate set from the command line. If UINT32_MAX, it was not set. */ int cmd_baudrate; /* Serial port set from the command line. If NULL, it was not set. */ char *cmd_serial_port; }; struct native_tty_config { struct uart_config uart_config; }; /** * @brief Convert from uart_config to native_tty_bottom_cfg eqvivalent struct * * @param bottom_cfg * @param cfg * * @return 0 on success, negative errno otherwise. */ static int native_tty_conv_to_bottom_cfg(struct native_tty_bottom_cfg *bottom_cfg, const struct uart_config *cfg) { bottom_cfg->baudrate = cfg->baudrate; switch (cfg->parity) { case UART_CFG_PARITY_NONE: bottom_cfg->parity = NTB_PARITY_NONE; break; case UART_CFG_PARITY_ODD: bottom_cfg->parity = NTB_PARITY_ODD; break; case UART_CFG_PARITY_EVEN: bottom_cfg->parity = NTB_PARITY_EVEN; break; default: return -ENOTSUP; } switch (cfg->data_bits) { case UART_CFG_STOP_BITS_1: bottom_cfg->stop_bits = NTB_STOP_BITS_1; break; case UART_CFG_STOP_BITS_2: bottom_cfg->stop_bits = NTB_STOP_BITS_2; break; default: return -ENOTSUP; } switch (cfg->data_bits) { case UART_CFG_DATA_BITS_5: bottom_cfg->data_bits = NTB_DATA_BITS_5; break; case UART_CFG_DATA_BITS_6: bottom_cfg->data_bits = NTB_DATA_BITS_6; break; case UART_CFG_DATA_BITS_7: bottom_cfg->data_bits = NTB_DATA_BITS_7; break; case UART_CFG_DATA_BITS_8: bottom_cfg->data_bits = NTB_DATA_BITS_8; break; default: return -ENOTSUP; } if (cfg->flow_ctrl != UART_CFG_FLOW_CTRL_NONE) { WARN("Could not set flow control, any kind of hw flow control is not supported.\n"); return -ENOTSUP; } bottom_cfg->flow_ctrl = NTB_FLOW_CTRL_NONE; return 0; } /* * @brief Output a character towards the serial port * * @param dev UART device structure. * @param out_char Character to send. */ static void native_tty_uart_poll_out(const struct device *dev, unsigned char out_char) { struct native_tty_data *data = dev->data; int ret = nsi_host_write(data->fd, &out_char, 1); if (ret == -1) { ERROR("Could not write to %s\n", data->serial_port); } } /** * @brief Poll the device for input. * * @param dev UART device structure. * @param p_char Pointer to a character. * * @retval 0 If a character arrived. * @retval -1 If no character was available to read. */ static int native_tty_uart_poll_in(const struct device *dev, unsigned char *p_char) { struct native_tty_data *data = dev->data; return nsi_host_read(data->fd, p_char, 1) > 0 ? 0 : -1; } static int native_tty_configure(const struct device *dev, const struct uart_config *cfg) { int fd = ((struct native_tty_data *)dev->data)->fd; struct native_tty_bottom_cfg bottom_cfg; int rc = native_tty_conv_to_bottom_cfg(&bottom_cfg, cfg); if (rc) { WARN("Could not convert uart config to native tty bottom cfg\n"); return rc; } return native_tty_configure_bottom(fd, &bottom_cfg); } static int native_tty_serial_init(const struct device *dev) { struct native_tty_data *data = dev->data; struct uart_config uart_config = ((struct native_tty_config *)dev->config)->uart_config; /* Default value for cmd_serial_port is NULL, this is due to the set 's' type in * command line opts. If it is anything else then it was configured via command * line. */ if (data->cmd_serial_port) { data->serial_port = data->cmd_serial_port; } /* Default value for cmd_baudrate is UINT32_MAX, this is due to the set 'u' type in * command line opts. If it is anything else then it was configured via command * line. */ if (data->cmd_baudrate != UINT32_MAX) { uart_config.baudrate = data->cmd_baudrate; } /* Serial port needs to be set either in the devicetree or provided via command line * opts, if that is not the case, then abort. */ if (!data->serial_port) { ERROR("%s: path to the serial port was not set.\n", dev->name); } /* Try to open a serial port as with read/write access, also prevent serial port * from becoming the controlling terminal. */ data->fd = native_tty_open_tty_bottom(data->serial_port); if (native_tty_configure(dev, &uart_config)) { ERROR("%s: could not configure serial port %s\n", dev->name, data->serial_port); } posix_print_trace("%s connected to the serial port: %s\n", dev->name, data->serial_port); return 0; } static struct uart_driver_api native_tty_uart_driver_api = { .poll_out = native_tty_uart_poll_out, .poll_in = native_tty_uart_poll_in, #ifdef CONFIG_UART_USE_RUNTIME_CONFIGURE .configure = native_tty_configure, #endif }; #define NATIVE_TTY_INSTANCE(inst) \ static const struct native_tty_config native_tty_##inst##_cfg = { \ .uart_config = \ { \ .data_bits = UART_CFG_DATA_BITS_8, \ .flow_ctrl = UART_CFG_FLOW_CTRL_NONE, \ .parity = UART_CFG_PARITY_NONE, \ .stop_bits = UART_CFG_STOP_BITS_1, \ .baudrate = DT_INST_PROP(inst, current_speed), \ }, \ }; \ \ static struct native_tty_data native_tty_##inst##_data = { \ .serial_port = DT_INST_PROP_OR(inst, serial_port, NULL), \ }; \ \ DEVICE_DT_INST_DEFINE(inst, native_tty_serial_init, NULL, &native_tty_##inst##_data, \ &native_tty_##inst##_cfg, PRE_KERNEL_1, 55, \ &native_tty_uart_driver_api); DT_INST_FOREACH_STATUS_OKAY(NATIVE_TTY_INSTANCE); #define INST_NAME(inst) DEVICE_DT_NAME(DT_DRV_INST(inst)) #define NATIVE_TTY_COMMAND_LINE_OPTS(inst) \ { \ .option = INST_NAME(inst) "_port", \ .name = "\"serial_port\"", \ .type = 's', \ .dest = &native_tty_##inst##_data.cmd_serial_port, \ .descript = "Set a serial port for " INST_NAME(inst) " uart device, " \ "overriding the one in devicetree.", \ }, \ { \ .option = INST_NAME(inst) "_baud", \ .name = "baudrate", \ .type = 'u', \ .dest = &native_tty_##inst##_data.cmd_baudrate, \ .descript = "Set a baudrate for " INST_NAME(inst) " device, overriding the " \ "baudrate of " STRINGIFY(DT_INST_PROP(inst, current_speed)) \ "set in the devicetree.", \ }, /** * @brief Adds command line options for setting serial port and baud rate for each uart * device. */ static void native_tty_add_serial_options(void) { static struct args_struct_t opts[] = { DT_INST_FOREACH_STATUS_OKAY(NATIVE_TTY_COMMAND_LINE_OPTS) ARG_TABLE_ENDMARKER}; native_add_command_line_opts(opts); } #define NATIVE_TTY_CLEANUP(inst) \ if (native_tty_##inst##_data.fd != 0) { \ nsi_host_close(native_tty_##inst##_data.fd); \ } /** * @brief Cleans up any open serial ports on the exit. */ static void native_tty_cleanup_uart(void) { DT_INST_FOREACH_STATUS_OKAY(NATIVE_TTY_CLEANUP); } NATIVE_TASK(native_tty_add_serial_options, PRE_BOOT_1, 11); NATIVE_TASK(native_tty_cleanup_uart, ON_EXIT, 99);