soft_uart: add unit tests for the receiver and transmitter
Change-Id: Icdfa0c644548964d37940c32dc9dcfcfc53c3a19
Related: OS#4396
diff --git a/tests/soft_uart/soft_uart_test.c b/tests/soft_uart/soft_uart_test.c
new file mode 100644
index 0000000..f5597f3
--- /dev/null
+++ b/tests/soft_uart/soft_uart_test.c
@@ -0,0 +1,302 @@
+/*
+ * (C) 2023 by sysmocom - s.f.m.c. GmbH <info@sysmocom.de>
+ * Author: Vadim Yanitskiy <vyanitskiy@sysmocom.de>
+ *
+ * All Rights Reserved
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ */
+
+#include <stdio.h>
+#include <stdint.h>
+
+#include <osmocom/core/msgb.h>
+#include <osmocom/core/utils.h>
+#include <osmocom/core/soft_uart.h>
+
+static struct {
+ size_t data_len;
+ const uint8_t *data;
+} g_tx_cb_cfg;
+
+static void suart_rx_cb(void *priv, struct msgb *msg, unsigned int flags)
+{
+ fprintf(stdout, "%s(flags=%02x): %s\n",
+ __func__, flags, msgb_hexdump(msg));
+ msgb_free(msg);
+}
+
+static void suart_tx_cb(void *priv, struct msgb *msg)
+{
+ size_t n_bytes;
+
+ n_bytes = OSMO_MIN(g_tx_cb_cfg.data_len, msg->data_len);
+ if (g_tx_cb_cfg.data != NULL && n_bytes > 0)
+ memcpy(msgb_put(msg, n_bytes), g_tx_cb_cfg.data, n_bytes);
+
+ fprintf(stdout, "%s(len=%u/%u): %s\n",
+ __func__, msg->len, msg->data_len, msgb_hexdump(msg));
+}
+
+static const struct osmo_soft_uart_cfg suart_test_default_cfg = {
+ .num_data_bits = 8,
+ .num_stop_bits = 1,
+ .parity_mode = OSMO_SUART_PARITY_NONE,
+ .rx_buf_size = 128,
+ .rx_cb = &suart_rx_cb,
+ .tx_cb = &suart_tx_cb,
+};
+
+static void test_rx_exec(struct osmo_soft_uart *suart,
+ const char *input)
+{
+ for (unsigned int i = 0; input[i] != '\0'; i++) {
+ ubit_t ubit;
+
+ switch (input[i]) {
+ case '0':
+ case '1':
+ ubit = input[i] - '0';
+ osmo_soft_uart_rx_ubits(suart, &ubit, 1);
+ break;
+ case 'F':
+ printf("%s() @ %u: flush the Rx buffer\n", __func__, i);
+ osmo_soft_uart_flush_rx(suart);
+ break;
+ case ' ': /* padding */
+ continue;
+ default:
+ printf("%s() @ %u: unknown opcode '%c'\n",
+ __func__, i, input[i]);
+ break;
+ }
+ }
+}
+
+static void test_rx(void)
+{
+ struct osmo_soft_uart_cfg cfg;
+ struct osmo_soft_uart *suart;
+
+ suart = osmo_soft_uart_alloc(NULL, __func__, &suart_test_default_cfg);
+ OSMO_ASSERT(suart != NULL);
+
+ osmo_soft_uart_set_rx(suart, true);
+
+ printf("======== %s(): testing 8-N-1 (no data)\n", __func__);
+ test_rx_exec(suart, "F11111F11111F");
+
+ printf("======== %s(): testing 8-N-1 (fill up flush)\n", __func__);
+ cfg = suart_test_default_cfg;
+ cfg.rx_buf_size = 4;
+ osmo_soft_uart_configure(suart, &cfg);
+ test_rx_exec(suart, "11111" /* no data */
+ "0 01111011 1"
+ "0 10110101 1"
+ "0 01111101 1"
+ "0 11110111 1" /* filled up, expect flush */
+ "0 00000000 1"
+ "0 01010101 1"
+ "0 10101010 1"
+ "0 11111111 1" /* filled up, expect flush */
+ "F" /* flush! (for sanity) */
+ );
+
+ printf("======== %s(): testing 8-N-1 (HELLO)\n", __func__);
+ cfg = suart_test_default_cfg;
+ cfg.num_stop_bits = 1;
+ osmo_soft_uart_configure(suart, &cfg);
+ test_rx_exec(suart, "111111" /* no data */
+ "0 00010010 1F" /* 'H', flush! */
+ "0 10100010 1F" /* 'E', flush! */
+ "1111111111111" /* no data */
+ "0 00110010 1F" /* 'L', flush! */
+ "0 00110010 1F" /* 'L', flush! */
+ "1111111111111" /* no data */
+ "0 11110010 1F" /* 'O', flush! */
+ );
+
+ printf("======== %s(): testing 8-N-1 (framing errors)\n", __func__);
+ test_rx_exec(suart, "11111" /* no data */
+ "0 00000000 0" /* stop bit != 1, expect flush */
+ "0 01010101 0" /* stop bit != 1, expect flush */
+ "0 11111111 1" /* stop bit == 1, recovery */
+ "F" /* flush! */
+ );
+
+ printf("======== %s(): testing 8-N-2 (HELLO)\n", __func__);
+ cfg = suart_test_default_cfg;
+ cfg.num_stop_bits = 2;
+ osmo_soft_uart_configure(suart, &cfg);
+ test_rx_exec(suart, "11111111" /* no data */
+ "0 00010010 1F1F" /* 'H', flush! */
+ "0 10100010 1F1F" /* 'E', flush! */
+ "111111111111111" /* no data */
+ "0 00110010 1F1F" /* 'L', flush! */
+ "0 00110010 1F1F" /* 'L', flush! */
+ "111111111111111" /* no data */
+ "0 11110010 1F1F" /* 'O', flush! */
+ );
+
+ printf("======== %s(): testing 8-N-2 (framing errors)\n", __func__);
+ test_rx_exec(suart, "11111" /* no data */
+ "0 00000000 00" /* stop bit != 1, expect flush */
+ "0 01010101 01" /* stop bit != 1, expect flush */
+ "0 10101010 10" /* stop bit != 1, expect flush */
+ "0 11111111 11" /* stop bit == 1, recovery */
+ "F" /* flush! (for sanity) */
+ );
+
+
+ printf("======== %s(): testing 8-E-1 (invalid parity)\n", __func__);
+ cfg = suart_test_default_cfg;
+ cfg.parity_mode = OSMO_SUART_PARITY_EVEN;
+ osmo_soft_uart_configure(suart, &cfg);
+ test_rx_exec(suart, "1111111" /* no data */
+ "0 00000000 1 1" /* odd parity, expect flush */
+ "0 10000000 0 1" /* odd parity, expect flush */
+ "0 11111111 1 1" /* odd parity, expect flush */
+ "F" /* flush! (for sanity) */
+ );
+ printf("======== %s(): testing 8-E-1 (valid parity)\n", __func__);
+ test_rx_exec(suart, "1111111" /* no data */
+ "0 00000000 0 1"
+ "0 11111111 0 1"
+ "0 01010101 0 1"
+ "0 10101010 0 1"
+ "F" /* flush! */
+ "0 00000001 1 1"
+ "0 00000111 1 1"
+ "0 00011111 1 1"
+ "0 01111111 1 1"
+ "F" /* flush! */
+ );
+
+ printf("======== %s(): testing 8-O-1 (invalid parity)\n", __func__);
+ cfg = suart_test_default_cfg;
+ cfg.parity_mode = OSMO_SUART_PARITY_ODD;
+ osmo_soft_uart_configure(suart, &cfg);
+ test_rx_exec(suart,
+ "0 00000000 0 1" /* even parity, expect flush */
+ "0 10000000 1 1" /* even parity, expect flush */
+ "0 11111111 0 1" /* even parity, expect flush */
+ "F" /* flush! (for sanity) */
+ );
+ printf("======== %s(): testing 8-O-1 (valid parity)\n", __func__);
+ test_rx_exec(suart, "1111111" /* no data */
+ "0 00000000 1 1"
+ "0 11111111 1 1"
+ "0 01010101 1 1"
+ "0 10101010 1 1"
+ "F" /* flush! */
+ "0 00000001 0 1"
+ "0 00000111 0 1"
+ "0 00011111 0 1"
+ "0 01111111 0 1"
+ "F" /* flush! */
+ );
+
+ osmo_soft_uart_free(suart);
+}
+
+static void test_tx_rx_exec_one(struct osmo_soft_uart *suart,
+ size_t n_bits_total, size_t n_bits_frame)
+{
+ ubit_t tx_buf[n_bits_total];
+ ubit_t *ptr = &tx_buf[0];
+ int rc;
+
+ rc = osmo_soft_uart_tx_ubits(suart, &tx_buf[0], n_bits_total);
+ OSMO_ASSERT(rc == 0);
+
+ rc = osmo_soft_uart_rx_ubits(suart, &tx_buf[0], n_bits_total);
+ OSMO_ASSERT(rc == 0);
+ osmo_soft_uart_flush_rx(suart);
+
+ printf("%s(n_bits_total=%zu):", __func__, n_bits_total);
+ while (n_bits_total > 0) {
+ size_t n_bits = OSMO_MIN(n_bits_frame, n_bits_total);
+ printf(" %s", osmo_ubit_dump(ptr, n_bits));
+ n_bits_total -= n_bits;
+ ptr += n_bits;
+ }
+ printf("\n");
+}
+
+static void test_tx_rx_exec(struct osmo_soft_uart *suart, size_t n_bits_frame)
+{
+ const uint8_t tx_data[][4] = {
+ { 0xde, 0xad, 0xbe, 0xef },
+ { 0x00, 0xaa, 0x55, 0xff },
+ { 0x01, 0x02, 0x04, 0x08 },
+ { 0x10, 0x20, 0x40, 0x80 },
+ };
+
+ for (size_t i = 0; i < ARRAY_SIZE(tx_data); i++) {
+ g_tx_cb_cfg.data_len = 4;
+ g_tx_cb_cfg.data = tx_data[i];
+ test_tx_rx_exec_one(suart, 4 * n_bits_frame, n_bits_frame);
+ }
+
+ g_tx_cb_cfg.data_len = 0;
+ g_tx_cb_cfg.data = NULL;
+ test_tx_rx_exec_one(suart, 4 * n_bits_frame, n_bits_frame);
+}
+
+static void test_tx_rx(void)
+{
+ struct osmo_soft_uart_cfg cfg;
+ struct osmo_soft_uart *suart;
+
+ suart = osmo_soft_uart_alloc(NULL, __func__, &suart_test_default_cfg);
+ OSMO_ASSERT(suart != NULL);
+
+ osmo_soft_uart_set_tx(suart, true);
+ osmo_soft_uart_set_rx(suart, true);
+
+ printf("======== %s(): testing 8-N-1\n", __func__);
+ test_tx_rx_exec(suart, (1 + 8 + 1));
+
+ printf("======== %s(): testing 8-N-2\n", __func__);
+ cfg = suart_test_default_cfg;
+ cfg.num_stop_bits = 2;
+ osmo_soft_uart_configure(suart, &cfg);
+ test_tx_rx_exec(suart, (1 + 8 + 2));
+
+ printf("======== %s(): testing 8-E-1\n", __func__);
+ cfg = suart_test_default_cfg;
+ cfg.parity_mode = OSMO_SUART_PARITY_EVEN;
+ osmo_soft_uart_configure(suart, &cfg);
+ test_tx_rx_exec(suart, (1 + 8 + 1 + 1));
+
+ printf("======== %s(): testing 8-O-1\n", __func__);
+ cfg = suart_test_default_cfg;
+ cfg.parity_mode = OSMO_SUART_PARITY_ODD;
+ osmo_soft_uart_configure(suart, &cfg);
+ test_tx_rx_exec(suart, (1 + 8 + 1 + 1));
+
+ printf("======== %s(): testing 6-N-1\n", __func__);
+ cfg = suart_test_default_cfg;
+ cfg.num_data_bits = 6;
+ osmo_soft_uart_configure(suart, &cfg);
+ test_tx_rx_exec(suart, (1 + 6 + 1));
+
+ osmo_soft_uart_free(suart);
+}
+
+int main(int argc, char **argv)
+{
+ test_rx();
+ test_tx_rx();
+
+ return 0;
+}