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Message-ID: <9ad4b4a8-988e-f185-f80c-6f15f341ce8c@linaro.org>
Date:   Mon, 8 Aug 2022 12:01:28 +0300
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Subject: Re: [PATCH 1/3] dt-bindings: spi: stm32: Add st,dual-flash property
 in st,stm32-qspi.yaml
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To:     patrice.chotard@foss.st.com, Mark Brown <broonie@kernel.org>,
        Alexandre Torgue <alexandre.torgue@foss.st.com>,
        robh+dt@kernel.org, krzysztof.kozlowski+dt@linaro.org
Cc:     linux-spi@vger.kernel.org,
        linux-stm32@st-md-mailman.stormreply.com,
        linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org,
        christophe.kerello@foss.st.com, devicetree@vger.kernel.org
References: <20220808074051.44736-1-patrice.chotard@foss.st.com>
 <20220808074051.44736-2-patrice.chotard@foss.st.com>
From:   Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
In-Reply-To: <20220808074051.44736-2-patrice.chotard@foss.st.com>
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On 08/08/2022 10:40, patrice.chotard@foss.st.com wrote:
> From: Patrice Chotard <patrice.chotard@foss.st.com>
> 
> 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@foss.st.com>
> ---
>  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?

Best regards,
Krzysztof