mtd: spi-nor: core: use 2 data bytes for template ops

The template ops used in spi_nor_spimem_check_pp() and
spi_nor_spimem_check_readop() currently set the data phase to 1 byte
long. This is problematic for 8D-8D-8D protocol where odd length data
phase is invalid since one cycle transfers 2 bytes and odd number of
bytes would mean half a cycle is left over. This could result in a
controller rejecting the op as "not supported" even though it actually
supports the protocol.

Change the data length to 2 bytes in these templates. One might argue
that this should only be done for 8D-8D-8D operations but when talking
about these templates, there is no functional difference between one and
two bytes, even in STR modes.

Signed-off-by: Pratyush Yadav <p.yadav@ti.com>
Signed-off-by: Tudor Ambarus <tudor.ambarus@microchip.com>
Reviewed-by: Michael Walle <michael@walle.cc>
Link: https://lore.kernel.org/r/20210531181757.19458-2-p.yadav@ti.com

diff --git a/drivers/mtd/spi-nor/core.c b/drivers/mtd/spi-nor/core.c
index bf9a83a..84a21b5 100644 (file)
--- a/drivers/mtd/spi-nor/core.c
+++ b/drivers/mtd/spi-nor/core.c
@@ -2141,7 +2141,7 @@ static int spi_nor_spimem_check_readop(struct spi_nor *nor,
        struct spi_mem_op op = SPI_MEM_OP(SPI_MEM_OP_CMD(read->opcode, 0),
                                          SPI_MEM_OP_ADDR(3, 0, 0),
                                          SPI_MEM_OP_DUMMY(1, 0),
-                                         SPI_MEM_OP_DATA_IN(1, NULL, 0));
+                                         SPI_MEM_OP_DATA_IN(2, NULL, 0));
 
        spi_nor_spimem_setup_op(nor, &op, read->proto);
 
@@ -2167,7 +2167,7 @@ static int spi_nor_spimem_check_pp(struct spi_nor *nor,
        struct spi_mem_op op = SPI_MEM_OP(SPI_MEM_OP_CMD(pp->opcode, 0),
                                          SPI_MEM_OP_ADDR(3, 0, 0),
                                          SPI_MEM_OP_NO_DUMMY,
-                                         SPI_MEM_OP_DATA_OUT(1, NULL, 0));
+                                         SPI_MEM_OP_DATA_OUT(2, NULL, 0));
 
        spi_nor_spimem_setup_op(nor, &op, pp->proto);