drivers: spi: stm32h7: avoid unnecessary suspend

The SPI stm32 H7 driver always suspends the SPI transaction
when finishing the transceive operation. This, according to
the stm32 H7 datasheet, must only be done when the SPI master
is configured as receive-only, and the driver always
configures it as full-duplex.

Hence, remove this unnecessary operation for clarify and for
a potential reduction in the minimum time between SPI
transceive operations.

Signed-off-by: Daniel Gaston Ochoa <[email protected]>

Author: dgastonochoa

drivers/spi/spi_ll_stm32.h

@@ -219,26 +219,16 @@ static inline void ll_func_set_fifo_threshold_16bit(SPI_TypeDef *spi)
 static inline void ll_func_disable_spi(SPI_TypeDef *spi)
 {
 #if DT_HAS_COMPAT_STATUS_OKAY(st_stm32h7_spi)
-	if (LL_SPI_IsActiveMasterTransfer(spi)) {
-		LL_SPI_SuspendMasterTransfer(spi);
-		while (LL_SPI_IsActiveMasterTransfer(spi)) {
-			/* NOP */
-		}
-	}
-
-	LL_SPI_Disable(spi);
-	while (LL_SPI_IsEnabled(spi)) {
-		/* NOP */
-	}
-
 	/* Flush RX buffer */
 	while (LL_SPI_IsActiveFlag_RXP(spi)) {
 		(void)LL_SPI_ReceiveData8(spi);
 	}
-	LL_SPI_ClearFlag_SUSP(spi);
-#else
-	LL_SPI_Disable(spi);
 #endif /* st_stm32h7_spi */
+	LL_SPI_Disable(spi);
+
+	while (LL_SPI_IsEnabled(spi)) {
+		/* NOP */
+	}
 }
 
 #endif	/* ZEPHYR_DRIVERS_SPI_SPI_LL_STM32_H_ */