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* [PATCH] ARM: dts: colibri-imx6ull: Change drive strength for usdhc2
@ 2021-03-04  9:31 Philippe Schenker
  2021-03-04 11:24 ` Fabio Estevam
  2021-03-08  1:30 ` Shawn Guo
  0 siblings, 2 replies; 3+ messages in thread
From: Philippe Schenker @ 2021-03-04  9:31 UTC (permalink / raw)
  To: devicetree
  Cc: Philippe Schenker, Fabio Estevam, NXP Linux Team,
	Pengutronix Kernel Team, Rob Herring, Sascha Hauer, Shawn Guo,
	linux-arm-kernel, linux-kernel

The current setting reflects about 86 Ohms of source-impedance
on the SDIO signals where the WiFi board is hooked up. PCB traces are
routed with 50 Ohms impedance and there are no serial resistors on
those traces.

This commit changes the source-impedance to 52 Ohms to better match our
hardware design.

The impedances given in this commit message refer to 3.3V operation.

Signed-off-by: Philippe Schenker <philippe.schenker@toradex.com>

---

 arch/arm/boot/dts/imx6ull-colibri.dtsi | 12 ++++++------
 1 file changed, 6 insertions(+), 6 deletions(-)

diff --git a/arch/arm/boot/dts/imx6ull-colibri.dtsi b/arch/arm/boot/dts/imx6ull-colibri.dtsi
index 4436556624d6..0cdbf7b6e728 100644
--- a/arch/arm/boot/dts/imx6ull-colibri.dtsi
+++ b/arch/arm/boot/dts/imx6ull-colibri.dtsi
@@ -522,12 +522,12 @@ MX6UL_PAD_SD1_DATA3__USDHC1_DATA3	0x170b9
 
 	pinctrl_usdhc2: usdhc2-grp {
 		fsl,pins = <
-			MX6UL_PAD_CSI_DATA00__USDHC2_DATA0	0x17059
-			MX6UL_PAD_CSI_DATA01__USDHC2_DATA1	0x17059
-			MX6UL_PAD_CSI_DATA02__USDHC2_DATA2	0x17059
-			MX6UL_PAD_CSI_DATA03__USDHC2_DATA3	0x17059
-			MX6UL_PAD_CSI_HSYNC__USDHC2_CMD		0x17059
-			MX6UL_PAD_CSI_VSYNC__USDHC2_CLK		0x17059
+			MX6UL_PAD_CSI_DATA00__USDHC2_DATA0	0x17069
+			MX6UL_PAD_CSI_DATA01__USDHC2_DATA1	0x17069
+			MX6UL_PAD_CSI_DATA02__USDHC2_DATA2	0x17069
+			MX6UL_PAD_CSI_DATA03__USDHC2_DATA3	0x17069
+			MX6UL_PAD_CSI_HSYNC__USDHC2_CMD		0x17069
+			MX6UL_PAD_CSI_VSYNC__USDHC2_CLK		0x17069
 
 			MX6UL_PAD_GPIO1_IO03__OSC32K_32K_OUT	0x10
 		>;
-- 
2.30.1


^ permalink raw reply related	[flat|nested] 3+ messages in thread

* Re: [PATCH] ARM: dts: colibri-imx6ull: Change drive strength for usdhc2
  2021-03-04  9:31 [PATCH] ARM: dts: colibri-imx6ull: Change drive strength for usdhc2 Philippe Schenker
@ 2021-03-04 11:24 ` Fabio Estevam
  2021-03-08  1:30 ` Shawn Guo
  1 sibling, 0 replies; 3+ messages in thread
From: Fabio Estevam @ 2021-03-04 11:24 UTC (permalink / raw)
  To: Philippe Schenker
  Cc: open list:OPEN FIRMWARE AND FLATTENED DEVICE TREE BINDINGS,
	NXP Linux Team, Pengutronix Kernel Team, Rob Herring,
	Sascha Hauer, Shawn Guo,
	moderated list:ARM/FREESCALE IMX / MXC ARM ARCHITECTURE,
	linux-kernel

Hi Philippe,

On Thu, Mar 4, 2021 at 6:31 AM Philippe Schenker
<philippe.schenker@toradex.com> wrote:
>
> The current setting reflects about 86 Ohms of source-impedance
> on the SDIO signals where the WiFi board is hooked up. PCB traces are
> routed with 50 Ohms impedance and there are no serial resistors on
> those traces.
>
> This commit changes the source-impedance to 52 Ohms to better match our
> hardware design.
>
> The impedances given in this commit message refer to 3.3V operation.
>
> Signed-off-by: Philippe Schenker <philippe.schenker@toradex.com>

Reviewed-by: Fabio Estevam <festevam@gmail.com>

^ permalink raw reply	[flat|nested] 3+ messages in thread

* Re: [PATCH] ARM: dts: colibri-imx6ull: Change drive strength for usdhc2
  2021-03-04  9:31 [PATCH] ARM: dts: colibri-imx6ull: Change drive strength for usdhc2 Philippe Schenker
  2021-03-04 11:24 ` Fabio Estevam
@ 2021-03-08  1:30 ` Shawn Guo
  1 sibling, 0 replies; 3+ messages in thread
From: Shawn Guo @ 2021-03-08  1:30 UTC (permalink / raw)
  To: Philippe Schenker
  Cc: devicetree, Fabio Estevam, NXP Linux Team,
	Pengutronix Kernel Team, Rob Herring, Sascha Hauer,
	linux-arm-kernel, linux-kernel

On Thu, Mar 04, 2021 at 10:31:39AM +0100, Philippe Schenker wrote:
> The current setting reflects about 86 Ohms of source-impedance
> on the SDIO signals where the WiFi board is hooked up. PCB traces are
> routed with 50 Ohms impedance and there are no serial resistors on
> those traces.
> 
> This commit changes the source-impedance to 52 Ohms to better match our
> hardware design.
> 
> The impedances given in this commit message refer to 3.3V operation.
> 
> Signed-off-by: Philippe Schenker <philippe.schenker@toradex.com>

Applied, thanks.

^ permalink raw reply	[flat|nested] 3+ messages in thread

end of thread, other threads:[~2021-03-08  1:31 UTC | newest]

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2021-03-04  9:31 [PATCH] ARM: dts: colibri-imx6ull: Change drive strength for usdhc2 Philippe Schenker
2021-03-04 11:24 ` Fabio Estevam
2021-03-08  1:30 ` Shawn Guo

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