[nrf fromlist] tests: drivers: uart: uart_mix_fifo_poll: Move counter handling

Move enabling of counter to the test instead of test setup. Test may be
skipped in some configurations and in that case counter shall not be
started so by moving setup to the test code allows skipping test before
counter is started.

Upstream PR #: 84240

Signed-off-by: Krzysztof Chruściński <[email protected]>

Author: nordic-krch

tests/drivers/uart/uart_mix_fifo_poll/src/main.c

@@ -147,13 +147,6 @@ static void counter_top_handler(const struct device *dev, void *user_data)
 
 static void init_test(int idx)
 {
-	int err;
-	struct counter_top_cfg top_cfg = {
-		.callback = counter_top_handler,
-		.user_data = NULL,
-		.flags = 0
-	};
-
 	memset(source, 0, sizeof(source));
 	async_rx_enabled = false;
 	uart_dev = duts[idx].dev;
@@ -170,19 +163,6 @@ static void init_test(int idx)
 			uart_irq_callback_set(uart_dev, int_driven_callback);
 		}
 	}
-
-	/* Setup counter which will periodically enable/disable UART RX,
-	 * Disabling RX should lead to flow control being activated.
-	 */
-	zassert_true(device_is_ready(counter_dev));
-
-	top_cfg.ticks = counter_us_to_ticks(counter_dev, 1000);
-
-	err = counter_set_top_value(counter_dev, &top_cfg);
-	zassert_true(err >= 0);
-
-	err = counter_start(counter_dev);
-	zassert_true(err >= 0);
 }
 
 static void rx_isr(void)
@@ -343,6 +323,24 @@ ZTEST(uart_mix_fifo_poll, test_mixed_uart_access)
 	int repeat = CONFIG_STRESS_TEST_REPS;
 	int err;
 	int num_of_contexts = ARRAY_SIZE(test_data);
+	struct counter_top_cfg top_cfg = {
+		.callback = counter_top_handler,
+		.user_data = NULL,
+		.flags = 0
+	};
+
+	/* Setup counter which will periodically enable/disable UART RX,
+	 * Disabling RX should lead to flow control being activated.
+	 */
+	zassert_true(device_is_ready(counter_dev));
+
+	top_cfg.ticks = counter_us_to_ticks(counter_dev, 1000);
+
+	err = counter_set_top_value(counter_dev, &top_cfg);
+	zassert_true(err >= 0);
+
+	err = counter_start(counter_dev);
+	zassert_true(err >= 0);
 
 	for (int i = 0; i < ARRAY_SIZE(test_data); i++) {
 		init_buf(txbuf[i], sizeof(txbuf[i]), i);
@@ -387,6 +385,9 @@ ZTEST(uart_mix_fifo_poll, test_mixed_uart_access)
 				"%d: Unexpected rx bytes count (%d/%d)",
 				i, source[i].cnt, repeat);
 	}
+
+	err = counter_stop(counter_dev);
+	zassert_true(err >= 0);
 }
 
 void *uart_mix_setup(void)