drivers: mspi: add checking if data pins are not overlapping

Add checking if one data line is not assigned to more than one
GPIO pin.

Signed-off-by: Magdalena Pastula <magdalena.pastula@nordicsemi.no>

Author: magp-nordic

drivers/mspi/mspi_nrfe.c

@@ -28,6 +28,7 @@ LOG_MODULE_REGISTER(mspi_nrfe, CONFIG_MSPI_LOG_LEVEL);
 #define EP_SEND_TIMEOUT_MS	     10
 #define EXTREME_DRIVE_FREQ_THRESHOLD 32000000
 #define CNT0_TOP_CALCULATE(freq)     (NRFX_CEIL_DIV(SystemCoreClock, freq * 2) - 1)
+#define DATA_LINE_INDEX(pinctr_fun)  (pinctr_fun - NRF_FUN_SDP_MSPI_DQ0)
 
 #ifdef CONFIG_SOC_NRF54L15
 
@@ -348,6 +349,11 @@ static int check_pin_assignments(const struct pinctrl_state *state)
 	uint8_t cs_pins[NRFE_MSPI_PINS_MAX];
 	uint8_t cs_pins_cnt = 0;
 	uint32_t psel = 0;
+	uint32_t pin_fun = 0;
+
+	for (uint8_t i = 0; i < NRFE_MSPI_DATA_LINE_CNT_MAX; i++) {
+		data_pins[i] = UINT8_MAX;
+	}
 
 	for (uint8_t i = 0; i < state->pin_cnt; i++) {
 		psel = NRF_GET_PIN(state->pins[i]);
@@ -356,12 +362,18 @@ static int check_pin_assignments(const struct pinctrl_state *state)
 				NRFE_MSPI_PORT_NUMBER);
 			return -ENOTSUP;
 		}
-		switch (NRF_GET_FUN(state->pins[i])) {
+		pin_fun = NRF_GET_FUN(state->pins[i]);
+		switch (pin_fun) {
 		case NRF_FUN_SDP_MSPI_DQ0:
 		case NRF_FUN_SDP_MSPI_DQ1:
 		case NRF_FUN_SDP_MSPI_DQ2:
 		case NRF_FUN_SDP_MSPI_DQ3:
-			data_pins[data_pins_cnt] = NRF_PIN_NUMBER_TO_PIN(psel);
+			if (data_pins[DATA_LINE_INDEX(pin_fun)] != UINT8_MAX) {
+				LOG_ERR("This pin is assigned to an already taken data line: %d.%d.",
+					NRF_PIN_NUMBER_TO_PORT(psel), NRF_PIN_NUMBER_TO_PIN(psel));
+				return -EINVAL;
+			}
+			data_pins[DATA_LINE_INDEX(pin_fun)] = NRF_PIN_NUMBER_TO_PIN(psel);
 			data_pins_cnt++;
 			break;
 		case NRF_FUN_SDP_MSPI_DQ4:
@@ -386,7 +398,7 @@ static int check_pin_assignments(const struct pinctrl_state *state)
 			}
 			break;
 		default:
-			LOG_ERR("Not supported pin function: %d", NRF_GET_FUN(state->pins[i]));
+			LOG_ERR("Not supported pin function: %d", pin_fun);
 			return -ENOTSUP;
 		}
 	}