tests: spi_loopback: Specify expected CS on helper func

The helper function should have the flexibility to have different
expected CS counts. Namely, the test cases where the transfer is
essentially empty should not need to assert CS and many platforms are
failing on CS testing currently due to expecting CS assert and deassert
despite it being a 0 clock/bit transfer being specified.

Signed-off-by: Declan Snyder <declan.snyder@nxp.com>

Author: decsny

tests/drivers/spi/spi_loopback/src/spi.c

@@ -204,7 +204,8 @@ static int spi_loopback_gpio_cs_loopback_init(void)
 /* just a wrapper of the driver transceive call with ztest error assert */
 static void spi_loopback_transceive(struct spi_dt_spec *const spec,
 				    const struct spi_buf_set *const tx,
-				    const struct spi_buf_set *const rx)
+				    const struct spi_buf_set *const rx,
+				    int expected_cs_count)
 {
 	int ret;
 
@@ -217,8 +218,7 @@ static void spi_loopback_transceive(struct spi_dt_spec *const spec,
 		ztest_test_skip();
 	}
 	zassert_ok(ret, "SPI transceive failed, code %d", ret);
-	/* There should be two CS triggers during the transaction, start and end */
-	zassert_false(spi_loopback_gpio_cs_loopback_check(2));
+	zassert_ok(spi_loopback_gpio_cs_loopback_check(expected_cs_count));
 	zassert_ok(pm_device_runtime_put(spec->bus));
 }
 
@@ -285,7 +285,7 @@ ZTEST(spi_loopback, test_spi_complete_multiple)
 							      buffer_rx, BUF_SIZE,
 							      buffer2_rx, BUF2_SIZE);
 
-	spi_loopback_transceive(spec, &tx, &rx);
+	spi_loopback_transceive(spec, &tx, &rx, 2);
 
 	spi_loopback_compare_bufs(buffer_tx, buffer_rx, BUF_SIZE,
 				  buffer_print_tx, buffer_print_rx);
@@ -315,7 +315,7 @@ ZTEST(spi_loopback, test_spi_complete_multiple_timed)
 
 	/* since this is a test program, there shouldn't be much to interfere with measurement */
 	start_time = k_cycle_get_32();
-	spi_loopback_transceive(spec, &tx, &rx);
+	spi_loopback_transceive(spec, &tx, &rx, 2);
 	end_time = k_cycle_get_32();
 
 	zassert_ok(pm_device_runtime_put(spec->bus));
@@ -391,7 +391,7 @@ void spi_loopback_test_mode(struct spi_dt_spec *spec, bool cpol, bool cpha)
 		spec->config.operation &= ~SPI_MODE_CPHA;
 	}
 
-	spi_loopback_transceive(spec, &tx, &rx);
+	spi_loopback_transceive(spec, &tx, &rx, 2);
 
 	spec->config.operation = original_op;
 
@@ -446,7 +446,7 @@ ZTEST(spi_loopback, test_spi_null_tx_buf)
 
 	(void)memset(buffer_rx, 0x77, BUF_SIZE);
 
-	spi_loopback_transceive(spec, &tx, &rx);
+	spi_loopback_transceive(spec, &tx, &rx, 2);
 
 	spi_loopback_compare_bufs(expected_nop_return_buf, buffer_rx, BUF_SIZE,
 				  buffer_print_rx, buffer_print_rx);
@@ -462,7 +462,7 @@ ZTEST(spi_loopback, test_spi_rx_half_start)
 
 	(void)memset(buffer_rx, 0, BUF_SIZE);
 
-	spi_loopback_transceive(spec, &tx, &rx);
+	spi_loopback_transceive(spec, &tx, &rx, 2);
 
 	spi_loopback_compare_bufs(buffer_tx, buffer_rx, 8,
 				  buffer_print_tx, buffer_print_rx);
@@ -484,7 +484,7 @@ ZTEST(spi_loopback, test_spi_rx_half_end)
 
 	(void)memset(buffer_rx, 0, BUF_SIZE);
 
-	spi_loopback_transceive(spec, &tx, &rx);
+	spi_loopback_transceive(spec, &tx, &rx, 2);
 
 	spi_loopback_compare_bufs(buffer_tx+8, buffer_rx, 8,
 				  buffer_print_tx, buffer_print_rx);
@@ -508,7 +508,7 @@ ZTEST(spi_loopback, test_spi_rx_every_4)
 
 	(void)memset(buffer_rx, 0, BUF_SIZE);
 
-	spi_loopback_transceive(spec, &tx, &rx);
+	spi_loopback_transceive(spec, &tx, &rx, 2);
 
 	spi_loopback_compare_bufs(buffer_tx+4, buffer_rx, 4,
 				  buffer_print_tx, buffer_print_rx);
@@ -536,7 +536,7 @@ ZTEST(spi_loopback, test_spi_rx_bigger_than_tx)
 
 	(void)memset(buffer_rx, 0xff, BUF_SIZE);
 
-	spi_loopback_transceive(spec, &tx, &rx);
+	spi_loopback_transceive(spec, &tx, &rx, 2);
 
 	spi_loopback_compare_bufs(buffer_tx, buffer_rx, tx_buf_size,
 				  buffer_print_tx, buffer_print_rx);
@@ -556,7 +556,7 @@ ZTEST(spi_loopback, test_spi_complete_large_transfers)
 	const struct spi_buf_set rx = spi_loopback_setup_xfer(rx_bufs_pool, 1,
 							      large_buffer_rx, BUF3_SIZE);
 
-	spi_loopback_transceive(spec, &tx, &rx);
+	spi_loopback_transceive(spec, &tx, &rx, 2);
 
 	zassert_false(memcmp(large_buffer_tx, large_buffer_rx, BUF3_SIZE),
 			"Large Buffer contents are different");
@@ -571,7 +571,7 @@ ZTEST(spi_loopback, test_spi_null_tx_buf_set)
 
 	(void)memset(buffer_rx, 0x77, BUF_SIZE);
 
-	spi_loopback_transceive(spec, NULL, &rx);
+	spi_loopback_transceive(spec, NULL, &rx, 2);
 
 	spi_loopback_compare_bufs(expected_nop_return_buf, buffer_rx, BUF_SIZE,
 				  buffer_print_rx, buffer_print_rx);
@@ -583,14 +583,14 @@ ZTEST(spi_loopback, test_spi_null_rx_buf_set)
 	const struct spi_buf_set tx = spi_loopback_setup_xfer(tx_bufs_pool, 1,
 							      buffer_tx, BUF_SIZE);
 
-	spi_loopback_transceive(spec, &tx, NULL);
+	spi_loopback_transceive(spec, &tx, NULL, 2);
 }
 
 ZTEST(spi_loopback, test_spi_null_tx_rx_buf_set)
 {
 	struct spi_dt_spec *spec = loopback_specs[spec_idx];
 
-	spi_loopback_transceive(spec, NULL, NULL);
+	spi_loopback_transceive(spec, NULL, NULL, 0);
 }
 
 ZTEST(spi_loopback, test_nop_nil_bufs)
@@ -599,7 +599,7 @@ ZTEST(spi_loopback, test_nop_nil_bufs)
 	const struct spi_buf_set tx = spi_loopback_setup_xfer(tx_bufs_pool, 1, NULL, 0);
 	const struct spi_buf_set rx = spi_loopback_setup_xfer(rx_bufs_pool, 1, NULL, 0);
 
-	spi_loopback_transceive(spec, &tx, &rx);
+	spi_loopback_transceive(spec, &tx, &rx, 0);
 
 	/* nothing really to check here, check is done in spi_loopback_transceive */
 }
@@ -614,7 +614,7 @@ ZTEST(spi_loopback, test_spi_write_back)
 
 	memcpy(buffer_rx, tx_data, sizeof(tx_data));
 
-	spi_loopback_transceive(spec, &set, &set);
+	spi_loopback_transceive(spec, &set, &set, 2);
 
 	spi_loopback_compare_bufs(tx_data, buffer_rx, BUF_SIZE,
 				  buffer_print_tx, buffer_print_rx);
@@ -635,7 +635,7 @@ ZTEST(spi_loopback, test_spi_same_buf_cmd)
 
 	memcpy(buffer_rx, tx_data, BUF_SIZE);
 
-	spi_loopback_transceive(spec, &tx, &rx);
+	spi_loopback_transceive(spec, &tx, &rx, 2);
 
 	spi_loopback_compare_bufs(tx_data, buffer_rx, 1,
 				  buffer_print_tx, buffer_print_rx);
@@ -666,7 +666,7 @@ static void spi_loopback_test_word_size(struct spi_dt_spec *spec,
 	const struct spi_buf_set rx = spi_loopback_setup_xfer(rx_bufs_pool, 1,
 							      rx_buffer, buffer_size);
 
-	spi_loopback_transceive(spec_copy, &tx, &rx);
+	spi_loopback_transceive(spec_copy, &tx, &rx, 2);
 
 	zassert_false(memcmp(compare_data, rx_buffer, buffer_size),
 		      "%d-bit word buffer contents are different", word_size);
@@ -960,11 +960,11 @@ ZTEST(spi_extra_api_features, test_spi_lock_release)
 	lock_spec->config.operation |= SPI_LOCK_ON;
 
 	zassert_ok(pm_device_runtime_get(lock_spec->bus));
-	spi_loopback_transceive(lock_spec, &tx, &rx);
+	spi_loopback_transceive(lock_spec, &tx, &rx, 2);
 	zassert_false(spi_release_dt(lock_spec), "SPI release failed");
 	zassert_ok(pm_device_runtime_put(lock_spec->bus));
 
-	spi_loopback_transceive(try_spec, &tx, &rx);
+	spi_loopback_transceive(try_spec, &tx, &rx, 2);
 
 	lock_spec->config.operation &= ~SPI_LOCK_ON;
 }
@@ -1020,7 +1020,7 @@ ZTEST(spi_extra_api_features, test_spi_hold_on_cs)
 	}
 
 	/* now just do a normal transfer to make sure there was no leftover effects */
-	spi_loopback_transceive(hold_spec, &tx, &rx);
+	spi_loopback_transceive(hold_spec, &tx, &rx, 2);
 
 	return;