1 /*
2 * Copyright (c) 2022 Trackunit Corporation
3 *
4 * SPDX-License-Identifier: Apache-2.0
5 */
6
7 #include <zephyr/modem/backend/tty.h>
8 #include "modem_backend_tty_bottom.h"
9
10 #include <zephyr/logging/log.h>
11 LOG_MODULE_REGISTER(modem_backend_tty, CONFIG_MODEM_MODULES_LOG_LEVEL);
12
13 #include <nsi_host_trampolines.h>
14 #include <string.h>
15
16 #define MODEM_BACKEND_TTY_THREAD_PRIO (10)
17 #define MODEM_BACKEND_TTY_THREAD_RUN_PERIOD_MS (1000)
18 #define MODEM_BACKEND_TTY_THREAD_POLL_DELAY (100)
19
20 #define MODEM_BACKEND_TTY_STATE_RUN_BIT (1)
21
modem_backend_tty_routine(void * p1,void * p2,void * p3)22 static void modem_backend_tty_routine(void *p1, void *p2, void *p3)
23 {
24 struct modem_backend_tty *backend = (struct modem_backend_tty *)p1;
25
26 ARG_UNUSED(p2);
27 ARG_UNUSED(p3);
28
29 /* Run until run flag is cleared. Check every MODEM_BACKEND_TTY_THREAD_RUN_PERIOD_MS */
30 while (atomic_test_bit(&backend->state, MODEM_BACKEND_TTY_STATE_RUN_BIT)) {
31
32 int ret = modem_backend_tty_poll_bottom(backend->tty_fd);
33
34 if (ret < 0) {
35 LOG_ERR("Poll operation failed");
36 break;
37 }
38
39 if (ret) {
40 modem_pipe_notify_receive_ready(&backend->pipe);
41 }
42
43 k_sleep(K_MSEC(MODEM_BACKEND_TTY_THREAD_POLL_DELAY));
44 }
45 }
46
modem_backend_tty_open(void * data)47 static int modem_backend_tty_open(void *data)
48 {
49 struct modem_backend_tty *backend = (struct modem_backend_tty *)data;
50
51 if (atomic_test_and_set_bit(&backend->state, MODEM_BACKEND_TTY_STATE_RUN_BIT)) {
52 return -EALREADY;
53 }
54
55 backend->tty_fd = modem_backend_tty_open_bottom(backend->tty_path);
56 if (backend->tty_fd < 0) {
57 return -EPERM;
58 }
59
60 k_thread_create(&backend->thread, backend->stack, backend->stack_size,
61 modem_backend_tty_routine, backend, NULL, NULL,
62 MODEM_BACKEND_TTY_THREAD_PRIO, 0, K_NO_WAIT);
63
64 modem_pipe_notify_opened(&backend->pipe);
65 return 0;
66 }
67
modem_backend_tty_transmit(void * data,const uint8_t * buf,size_t size)68 static int modem_backend_tty_transmit(void *data, const uint8_t *buf, size_t size)
69 {
70 struct modem_backend_tty *backend = (struct modem_backend_tty *)data;
71 int ret;
72
73 ret = nsi_host_write(backend->tty_fd, buf, size);
74 modem_pipe_notify_transmit_idle(&backend->pipe);
75 return ret;
76 }
77
modem_backend_tty_receive(void * data,uint8_t * buf,size_t size)78 static int modem_backend_tty_receive(void *data, uint8_t *buf, size_t size)
79 {
80 int ret;
81 struct modem_backend_tty *backend = (struct modem_backend_tty *)data;
82
83 ret = nsi_host_read(backend->tty_fd, buf, size);
84 return (ret < 0) ? 0 : ret;
85 }
86
modem_backend_tty_close(void * data)87 static int modem_backend_tty_close(void *data)
88 {
89 struct modem_backend_tty *backend = (struct modem_backend_tty *)data;
90
91 if (!atomic_test_and_clear_bit(&backend->state, MODEM_BACKEND_TTY_STATE_RUN_BIT)) {
92 return -EALREADY;
93 }
94
95 k_thread_join(&backend->thread, K_MSEC(MODEM_BACKEND_TTY_THREAD_RUN_PERIOD_MS * 2));
96 nsi_host_close(backend->tty_fd);
97 modem_pipe_notify_closed(&backend->pipe);
98 return 0;
99 }
100
101 static const struct modem_pipe_api modem_backend_tty_api = {
102 .open = modem_backend_tty_open,
103 .transmit = modem_backend_tty_transmit,
104 .receive = modem_backend_tty_receive,
105 .close = modem_backend_tty_close,
106 };
107
modem_backend_tty_init(struct modem_backend_tty * backend,const struct modem_backend_tty_config * config)108 struct modem_pipe *modem_backend_tty_init(struct modem_backend_tty *backend,
109 const struct modem_backend_tty_config *config)
110 {
111 __ASSERT_NO_MSG(backend != NULL);
112 __ASSERT_NO_MSG(config != NULL);
113 __ASSERT_NO_MSG(config->tty_path != NULL);
114
115 memset(backend, 0x00, sizeof(*backend));
116 backend->tty_path = config->tty_path;
117 backend->stack = config->stack;
118 backend->stack_size = config->stack_size;
119 atomic_set(&backend->state, 0);
120 modem_pipe_init(&backend->pipe, backend, &modem_backend_tty_api);
121 return &backend->pipe;
122 }
123
