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SubjectRe: [PATCH v2 01/10] spi: atmel-quadspi: cache MR value to avoid a write access
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On 01/31/2019 06:55 PM, Boris Brezillon wrote:
> On Thu, 31 Jan 2019 16:15:28 +0000
> <Tudor.Ambarus@microchip.com> wrote:
>
>> From: Tudor Ambarus <tudor.ambarus@microchip.com>
>>
>> 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@microchip.com>
>> ---
>> 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))
>
> if (aq->mr != QSPI_MR_SMM)

then I should probably rename mr to smm.

>
>> + qspi_writel(aq, QSPI_MR, QSPI_MR_SMM);
>
> You need to update ->mr here.

of course, thanks!

>
>>
>> mode = find_mode(op);
>> if (mode < 0)
>
>
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>
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