spi: stm32: qspi: Fix dual flash mode sanity test in stm32_qspi_setup()

Misplaced parenthesis make test of mode wrong in case mode is equal to
SPI_TX_OCTAL or SPI_RX_OCTAL.

Simplify this sanity test, if one of this bit is set, property
cs-gpio must be present in DT.

Fixes: a557fca ("spi: stm32_qspi: Add transfer_one_message() spi callback")
Cc: stable@vger.kernel.org
Signed-off-by: Patrice Chotard <patrice.chotard@foss.st.com>
Link: https://msgid.link/r/20240618132951.2743935-2-patrice.chotard@foss.st.com
Signed-off-by: Mark Brown <broonie@kernel.org>

Author: Patrice Chotard

drivers/spi/spi-stm32-qspi.c

@@ -653,9 +653,7 @@ static int stm32_qspi_setup(struct spi_device *spi)
 		return -EINVAL;
 
 	mode = spi->mode & (SPI_TX_OCTAL | SPI_RX_OCTAL);
-	if ((mode == SPI_TX_OCTAL || mode == SPI_RX_OCTAL) ||
-	    ((mode == (SPI_TX_OCTAL | SPI_RX_OCTAL)) &&
-	    gpiod_count(qspi->dev, "cs") == -ENOENT)) {
+	if (mode && gpiod_count(qspi->dev, "cs") == -ENOENT) {
 		dev_err(qspi->dev, "spi-rx-bus-width\\/spi-tx-bus-width\\/cs-gpios\n");
 		dev_err(qspi->dev, "configuration not supported\n");
 
@@ -676,10 +674,10 @@ static int stm32_qspi_setup(struct spi_device *spi)
 	qspi->cr_reg = CR_APMS | 3 << CR_FTHRES_SHIFT | CR_SSHIFT | CR_EN;
 
 	/*
-	 * Dual flash mode is only enable in case SPI_TX_OCTAL and SPI_TX_OCTAL
-	 * are both set in spi->mode and "cs-gpios" properties is found in DT
+	 * Dual flash mode is only enable in case SPI_TX_OCTAL or SPI_RX_OCTAL
+	 * is set in spi->mode and "cs-gpios" properties is found in DT
 	 */
-	if (mode == (SPI_TX_OCTAL | SPI_RX_OCTAL)) {
+	if (mode) {
 		qspi->cr_reg |= CR_DFM;
 		dev_dbg(qspi->dev, "Dual flash mode enable");
 	}