[PATCH v7 05/20] spi: mxic: Avoid endianness problems with 2-byte opcodes

[Pratyush Yadav <p.yadav@xxxxxx>]

spi-mem now supports 2-byte opcodes. Since we directly use the address
of the opcode in data transfer, the result can be different based on
whether the machine is little endian or big endian. So instead extract
the individual bytes from the opcode before using them.

Suggested-by: Boris Brezillon <boris.brezillon@xxxxxxxxxxxxx>
Signed-off-by: Pratyush Yadav <p.yadav@xxxxxx>
---
 drivers/spi/spi-mxic.c | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/drivers/spi/spi-mxic.c b/drivers/spi/spi-mxic.c
index 69491f3a515d..c3f4136a7c1d 100644
--- a/drivers/spi/spi-mxic.c
+++ b/drivers/spi/spi-mxic.c
@@ -356,6 +356,7 @@ static int mxic_spi_mem_exec_op(struct spi_mem *mem,
 	int nio = 1, i, ret;
 	u32 ss_ctrl;
 	u8 addr[8];
+	u8 cmd[2];
 
 	ret = mxic_spi_set_freq(mxic, mem->spi->max_speed_hz);
 	if (ret)
@@ -393,7 +394,10 @@ static int mxic_spi_mem_exec_op(struct spi_mem *mem,
 	writel(readl(mxic->regs + HC_CFG) | HC_CFG_MAN_CS_ASSERT,
 	       mxic->regs + HC_CFG);
 
-	ret = mxic_spi_data_xfer(mxic, &op->cmd.opcode, NULL, 1);
+	for (i = 0; i < op->cmd.nbytes; i++)
+		cmd[i] = op->cmd.opcode >> (8 * (op->cmd.nbytes - i - 1));
+
+	ret = mxic_spi_data_xfer(mxic, cmd, NULL, op->cmd.nbytes);
 	if (ret)
 		goto out;
 
-- 
2.26.2


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