1 /*
2 * Copyright (c) 2024 Argentum Systems Ltd.
3 *
4 * SPDX-License-Identifier: Apache-2.0
5 */
6
7 #include <zephyr/kernel.h>
8 #include <zephyr/device.h>
9 #include <zephyr/drivers/uart.h>
10 #include <zephyr/sys/ring_buffer.h>
11
12 #include <stdio.h>
13 #include <string.h>
14
15 struct patch_info {
16 const uint8_t * const name;
17
18 const struct device *rx_dev;
19 struct ring_buf *rx_ring_buf;
20 bool rx_error;
21 bool rx_overflow;
22
23 const struct device *tx_dev;
24 };
25
26 #define DEV_CONSOLE DEVICE_DT_GET(DT_CHOSEN(zephyr_console))
27 #define DEV_OTHER DEVICE_DT_GET(DT_CHOSEN(uart_passthrough))
28
29 #define RING_BUF_SIZE 64
30
31 RING_BUF_DECLARE(rb_console, RING_BUF_SIZE);
32 struct patch_info patch_c2o = {
33 .name = "c2o",
34
35 .rx_dev = DEV_CONSOLE,
36 .rx_ring_buf = &rb_console,
37 .rx_error = false,
38 .rx_overflow = false,
39
40 .tx_dev = DEV_OTHER,
41 };
42
43 RING_BUF_DECLARE(rb_other, RING_BUF_SIZE);
44 struct patch_info patch_o2c = {
45 .name = "o2c",
46
47 .rx_dev = DEV_OTHER,
48 .rx_ring_buf = &rb_other,
49 .rx_error = false,
50 .rx_overflow = false,
51
52 .tx_dev = DEV_CONSOLE,
53 };
54
uart_cb(const struct device * dev,void * ctx)55 static void uart_cb(const struct device *dev, void *ctx)
56 {
57 struct patch_info *patch = (struct patch_info *)ctx;
58 int ret;
59 uint8_t *buf;
60 uint32_t len;
61
62 while (uart_irq_update(patch->rx_dev) > 0) {
63 ret = uart_irq_rx_ready(patch->rx_dev);
64 if (ret < 0) {
65 patch->rx_error = true;
66 }
67 if (ret <= 0) {
68 break;
69 }
70
71 len = ring_buf_put_claim(patch->rx_ring_buf, &buf, RING_BUF_SIZE);
72 if (len == 0) {
73 /* no space for Rx, disable the IRQ */
74 uart_irq_rx_disable(patch->rx_dev);
75 patch->rx_overflow = true;
76 break;
77 }
78
79 ret = uart_fifo_read(patch->rx_dev, buf, len);
80 if (ret < 0) {
81 patch->rx_error = true;
82 }
83 if (ret <= 0) {
84 break;
85 }
86 len = ret;
87
88 ret = ring_buf_put_finish(patch->rx_ring_buf, len);
89 if (ret != 0) {
90 patch->rx_error = true;
91 break;
92 }
93 }
94 }
95
passthrough(struct patch_info * patch)96 static void passthrough(struct patch_info *patch)
97 {
98 int ret;
99 uint8_t *buf;
100 uint32_t len;
101
102 if (patch->rx_error) {
103 printk("<<%s: Rx Error!>>\n", patch->name);
104 patch->rx_error = false;
105 }
106
107 if (patch->rx_overflow) {
108 printk("<<%s: Rx Overflow!>>\n", patch->name);
109 patch->rx_overflow = false;
110 }
111
112 len = ring_buf_get_claim(patch->rx_ring_buf, &buf, RING_BUF_SIZE);
113 if (len == 0) {
114 goto done;
115 }
116
117 ret = uart_fifo_fill(patch->tx_dev, buf, len);
118 if (ret < 0) {
119 goto error;
120 }
121 len = ret;
122
123 ret = ring_buf_get_finish(patch->rx_ring_buf, len);
124 if (ret < 0) {
125 goto error;
126 }
127
128 done:
129 uart_irq_rx_enable(patch->rx_dev);
130 return;
131
132 error:
133 printk("<<%s: Tx Error!>>\n", patch->name);
134 }
135
main(void)136 int main(void)
137 {
138 printk("Console Device: %p\n", patch_c2o.rx_dev);
139 printk("Other Device: %p\n", patch_o2c.rx_dev);
140
141 uart_irq_callback_user_data_set(patch_c2o.rx_dev, uart_cb, (void *)&patch_c2o);
142 uart_irq_callback_user_data_set(patch_o2c.rx_dev, uart_cb, (void *)&patch_o2c);
143
144 for (;;) {
145 passthrough(&patch_c2o);
146 passthrough(&patch_o2c);
147 }
148
149 return 0;
150 }
151
