spi: add support for octal mode I/O data transfer

Add flags for Octal mode I/O data transfer
Required for the SPI controller which can do the data transfer (TX/RX)
on 8 data lines e.g. NXP FlexSPI controller.
 SPI_TX_OCTAL: transmit with 8 wires
 SPI_RX_OCTAL: receive with 8 wires

Signed-off-by: Yogesh Gaur <yogeshnarayan.gaur@nxp.com>
Reviewed-by: Boris Brezillon <boris.brezillon@bootlin.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
diff --git a/include/linux/spi/spi.h b/include/linux/spi/spi.h
index 6be77fa..0c1ca5d 100644
--- a/include/linux/spi/spi.h
+++ b/include/linux/spi/spi.h
@@ -154,7 +154,9 @@ struct spi_device {
 #define	SPI_TX_QUAD	0x200			/* transmit with 4 wires */
 #define	SPI_RX_DUAL	0x400			/* receive with 2 wires */
 #define	SPI_RX_QUAD	0x800			/* receive with 4 wires */
-#define SPI_CS_WORD	0x1000			/* toggle cs after each word */
+#define	SPI_CS_WORD	0x1000			/* toggle cs after each word */
+#define	SPI_TX_OCTAL	0x2000			/* transmit with 8 wires */
+#define	SPI_RX_OCTAL	0x4000			/* receive with 8 wires */
 	int			irq;
 	void			*controller_state;
 	void			*controller_data;