spi: atmel-quadspi: rework transfer macros

Split the TFRTYP_TRSFR_ bitfields in 2: one bit encoding the
mem/reg transfer type and one bit encoding the direction of
the transfer (read/write).

Remove NOP when setting read transfer type. Remove useless
setting of write transfer type when
op->data.dir == SPI_MEM_DATA_IN && !op->data.nbytes.

QSPI_IFR_TFRTYP_TRSFR_WRITE is specific just to sama5d2 qspi,
rename it to QSPI_IFR_SAMA5D2_WRITE_TRSFR.
Signed-off-by: Tudor Ambarus <tudor.ambarus@microchip.com>
Reviewed-by: Boris Brezillon <boris.brezillon@collabora.com>
Signed-off-by: Mark Brown <broonie@kernel.org>

drivers/spi/atmel-quadspi.c

@@ -113,11 +113,8 @@
 #define QSPI_IFR_OPTL_4BIT              (2 << 8)
 #define QSPI_IFR_OPTL_8BIT              (3 << 8)
 #define QSPI_IFR_ADDRL                  BIT(10)
-#define QSPI_IFR_TFRTYP_MASK            GENMASK(13, 12)
-#define QSPI_IFR_TFRTYP_TRSFR_READ      (0 << 12)
-#define QSPI_IFR_TFRTYP_TRSFR_READ_MEM  (1 << 12)
-#define QSPI_IFR_TFRTYP_TRSFR_WRITE     (2 << 12)
-#define QSPI_IFR_TFRTYP_TRSFR_WRITE_MEM (3 << 13)
+#define QSPI_IFR_TFRTYP_MEM		BIT(12)
+#define QSPI_IFR_SAMA5D2_WRITE_TRSFR	BIT(13)
 #define QSPI_IFR_CRM                    BIT(14)
 #define QSPI_IFR_NBDUM_MASK             GENMASK(20, 16)
 #define QSPI_IFR_NBDUM(n)               (((n) << 16) & QSPI_IFR_NBDUM_MASK)
@@ -275,10 +272,8 @@ static int atmel_qspi_exec_op(struct spi_mem *mem, const struct spi_mem_op *op)
 	if (op->data.nbytes)
 		ifr |= QSPI_IFR_DATAEN;
 
-	if (op->data.dir == SPI_MEM_DATA_IN && op->data.nbytes)
-		ifr |= QSPI_IFR_TFRTYP_TRSFR_READ;
-	else
-		ifr |= QSPI_IFR_TFRTYP_TRSFR_WRITE;
+	if (op->data.dir == SPI_MEM_DATA_OUT)
+		ifr |= QSPI_IFR_SAMA5D2_WRITE_TRSFR;
 
 	/* Clear pending interrupts */
 	(void)readl_relaxed(aq->regs + QSPI_SR);