Re: [PATCH 1/3] dt-bindings: spi: stm32: Add st,dual-flash property in st,stm32-qspi.yaml

From: Patrice CHOTARD
Date: Mon Aug 08 2022 - 12:09:26 EST


Hi Krzystof

On 8/8/22 11:01, Krzysztof Kozlowski wrote:
> On 08/08/2022 10:40, patrice.chotard@xxxxxxxxxxx wrote:
>> From: Patrice Chotard <patrice.chotard@xxxxxxxxxxx>
>>
>> Add new property st,dual-flash which allows to use the QSPI interface as a
>> communication channel using up to 8 qspi line.
>> This mode can only be used if cs-gpios property is defined.
>>
>> Signed-off-by: Patrice Chotard <patrice.chotard@xxxxxxxxxxx>
>> ---
>> Documentation/devicetree/bindings/spi/st,stm32-qspi.yaml | 8 ++++++++
>> 1 file changed, 8 insertions(+)
>>
>> diff --git a/Documentation/devicetree/bindings/spi/st,stm32-qspi.yaml b/Documentation/devicetree/bindings/spi/st,stm32-qspi.yaml
>> index 6ec6f556182f..5e4f9109799e 100644
>> --- a/Documentation/devicetree/bindings/spi/st,stm32-qspi.yaml
>> +++ b/Documentation/devicetree/bindings/spi/st,stm32-qspi.yaml
>> @@ -46,6 +46,14 @@ properties:
>> - const: tx
>> - const: rx
>>
>> + st,dual-flash:
>> + type: boolean
>> + description:
>> + Allows to use 8 data lines in case cs-gpios property is defined.
>
> It's named dual-flash, but what if you want to use QSPI to connect for
> example to FPGA?
>
> Also how is this related to parallel-memories property?

I called it "dual-flash" simply because it enable the dual flash feature of the QSPI block (bit CR_DFM : Dual Flash Mode)
which allows to use the 8 lines simultaneously of our dual QSPI block.

Best regards
Patrice


>
> Best regards,
> Krzysztof