2023-07-04 14:00:22

by Hugo Villeneuve

[permalink] [raw]
Subject: [PATCH] arm64: dts: imx8mn-var-som: add missing pull-up for onboard PHY reset pinmux

From: Hugo Villeneuve <[email protected]>

For SOMs with an onboard PHY, the RESET_N pull-up resistor is
currently deactivated in the pinmux configuration. When the pinmux
code selects the GPIO function for this pin, with a default direction
of input, this prevents the RESET_N pin from being taken to the proper
3.3V level (deasserted), and this results in the PHY being not
detected since it is held in reset.

Taken from RESET_N pin description in ADIN13000 datasheet:
This pin requires a 1K pull-up resistor to AVDD_3P3.

Activate the pull-up resistor to fix the issue.

Fixes: ade0176dd8a0 ("arm64: dts: imx8mn-var-som: Add Variscite VAR-SOM-MX8MN System on Module")
Signed-off-by: Hugo Villeneuve <[email protected]>
---
arch/arm64/boot/dts/freescale/imx8mn-var-som.dtsi | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/arch/arm64/boot/dts/freescale/imx8mn-var-som.dtsi b/arch/arm64/boot/dts/freescale/imx8mn-var-som.dtsi
index d3a67109d55b..b8946edf317b 100644
--- a/arch/arm64/boot/dts/freescale/imx8mn-var-som.dtsi
+++ b/arch/arm64/boot/dts/freescale/imx8mn-var-som.dtsi
@@ -358,7 +358,7 @@ MX8MN_IOMUXC_ENET_TXC_ENET1_RGMII_TXC 0x1f
MX8MN_IOMUXC_ENET_RXC_ENET1_RGMII_RXC 0x91
MX8MN_IOMUXC_ENET_RX_CTL_ENET1_RGMII_RX_CTL 0x91
MX8MN_IOMUXC_ENET_TX_CTL_ENET1_RGMII_TX_CTL 0x1f
- MX8MN_IOMUXC_GPIO1_IO09_GPIO1_IO9 0x19
+ MX8MN_IOMUXC_GPIO1_IO09_GPIO1_IO9 0x159
>;
};

--
2.30.2



2023-07-04 15:04:32

by Fabio Estevam

[permalink] [raw]
Subject: Re: [PATCH] arm64: dts: imx8mn-var-som: add missing pull-up for onboard PHY reset pinmux

On Tue, Jul 4, 2023 at 10:48 AM Hugo Villeneuve <[email protected]> wrote:
>
> From: Hugo Villeneuve <[email protected]>
>
> For SOMs with an onboard PHY, the RESET_N pull-up resistor is
> currently deactivated in the pinmux configuration. When the pinmux
> code selects the GPIO function for this pin, with a default direction
> of input, this prevents the RESET_N pin from being taken to the proper
> 3.3V level (deasserted), and this results in the PHY being not
> detected since it is held in reset.
>
> Taken from RESET_N pin description in ADIN13000 datasheet:
> This pin requires a 1K pull-up resistor to AVDD_3P3.
>
> Activate the pull-up resistor to fix the issue.
>
> Fixes: ade0176dd8a0 ("arm64: dts: imx8mn-var-som: Add Variscite VAR-SOM-MX8MN System on Module")
> Signed-off-by: Hugo Villeneuve <[email protected]>

Reviewed-by: Fabio Estevam <[email protected]>

2023-07-18 06:40:18

by Shawn Guo

[permalink] [raw]
Subject: Re: [PATCH] arm64: dts: imx8mn-var-som: add missing pull-up for onboard PHY reset pinmux

On Tue, Jul 04, 2023 at 09:48:00AM -0400, Hugo Villeneuve wrote:
> From: Hugo Villeneuve <[email protected]>
>
> For SOMs with an onboard PHY, the RESET_N pull-up resistor is
> currently deactivated in the pinmux configuration. When the pinmux
> code selects the GPIO function for this pin, with a default direction
> of input, this prevents the RESET_N pin from being taken to the proper
> 3.3V level (deasserted), and this results in the PHY being not
> detected since it is held in reset.
>
> Taken from RESET_N pin description in ADIN13000 datasheet:
> This pin requires a 1K pull-up resistor to AVDD_3P3.
>
> Activate the pull-up resistor to fix the issue.
>
> Fixes: ade0176dd8a0 ("arm64: dts: imx8mn-var-som: Add Variscite VAR-SOM-MX8MN System on Module")
> Signed-off-by: Hugo Villeneuve <[email protected]>

Applied, thanks!