Re: [PATCH v2 1/2] spi: dt-bindings: amlogic, meson-gx-spicc: Add pinctrl names for SPI signal states

From: neil . armstrong
Date: Fri Oct 07 2022 - 03:45:25 EST


On 07/10/2022 09:04, Krzysztof Kozlowski wrote:
On 06/10/2022 17:48, Neil Armstrong wrote:
On 06/10/2022 16:11, Krzysztof Kozlowski wrote:
On 06/10/2022 12:57, Amjad Ouled-Ameur wrote:
Hi Krzysztof,

Thank you for the review.

On 10/5/22 10:14, Krzysztof Kozlowski wrote:
On 04/10/2022 13:10, Amjad Ouled-Ameur wrote:
SPI pins of the SPICC Controller in Meson-GX needs to be controlled by
pin biais when idle. Therefore define three pinctrl names:
- default: SPI pins are controlled by spi function.
- idle-high: SCLK pin is pulled-up, but MOSI/MISO are still controlled
by spi function.
- idle-low: SCLK pin is pulled-down, but MOSI/MISO are still controlled
by spi function.

Reported-by: Da Xue <>
Signed-off-by: Neil Armstrong <narmstrong@xxxxxxxxxxxx>
Signed-off-by: Amjad Ouled-Ameur <aouledameur@xxxxxxxxxxxx>
.../devicetree/bindings/spi/amlogic,meson-gx-spicc.yaml | 15 +++++++++++++++
1 file changed, 15 insertions(+)

diff --git a/Documentation/devicetree/bindings/spi/amlogic,meson-gx-spicc.yaml b/Documentation/devicetree/bindings/spi/amlogic,meson-gx-spicc.yaml
index 0c10f7678178..53013e27f507 100644
--- a/Documentation/devicetree/bindings/spi/amlogic,meson-gx-spicc.yaml
+++ b/Documentation/devicetree/bindings/spi/amlogic,meson-gx-spicc.yaml
@@ -43,6 +43,14 @@ properties:
minItems: 1
maxItems: 2
+ pinctrl-0:
+ minItems: 1

Will fill it in next version.
+ pinctrl-1:
+ maxItems: 1
+ pinctrl-names: true
Why do you need all these in the bindings?

SPI clock bias needs to change at runtime depending on SPI mode, here is an example of

how this is supposed to be used ("spi_idle_low_pins" and "spi_idle_low_pins" are defined

in the second patch of this series):

I know what it the point in general of pinctrl configuration... But the
question is why do you need to specify them in the bindings? Core
handles that. IOW, do you require them and missing/incomplete pinctrl
should be reported?

Looking at other bindings, when specific pinctrl state names were requires, they were

Yes, the required and/or necessary entries were added to few other
bindings. Since Amjad did not make them required, why adding them? So I
repeat the question for the third time - why do you need to add them to
the bindings?

There's some bindings with pinctrl-names for specific states like rockchip/rockchip,dw-hdmi.yaml,
mediatek/mediatek,dpi.yaml, mmc/mtk-sd.yaml or mmc/fsl-imx-esdhc.yaml

And? Just because someone did something is not itself an argument. They
might have their reasons. If their reasons are applicable here, please
state them.

OK, I thought the reason was explicit, we find it worth documenting
those optional pinctrl states for when the spi lines are in idle state.

If it's not an enough good reason, we'll drop this patch.

Best regards,