From: Tudor Ambarus <tudor.ambarus@xxxxxxxxxxxxx> Cache MR value to avoid write access when setting the controller in Serial Memory Mode (SMM). SMM is set in exec_op() and not at probe time, to let room for future regular SPI support. Signed-off-by: Tudor Ambarus <tudor.ambarus@xxxxxxxxxxxxx> --- v2: cache MR value instead of moving the write access at probe drivers/spi/atmel-quadspi.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) diff --git a/drivers/spi/atmel-quadspi.c b/drivers/spi/atmel-quadspi.c index ddc712410812..fe05aee5d845 100644 --- a/drivers/spi/atmel-quadspi.c +++ b/drivers/spi/atmel-quadspi.c @@ -155,6 +155,7 @@ struct atmel_qspi { struct clk *clk; struct platform_device *pdev; u32 pending; + u32 mr; struct completion cmd_completion; }; @@ -238,7 +239,9 @@ static int atmel_qspi_exec_op(struct spi_mem *mem, const struct spi_mem_op *op) icr = QSPI_ICR_INST(op->cmd.opcode); ifr = QSPI_IFR_INSTEN; - qspi_writel(aq, QSPI_MR, QSPI_MR_SMM); + /* Set the QSPI controller in Serial Memory Mode */ + if (!(aq->mr & QSPI_MR_SMM)) + qspi_writel(aq, QSPI_MR, QSPI_MR_SMM); mode = find_mode(op); if (mode < 0) -- 2.9.5