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* [PATCH 1/4] ARM: dts: stm32: Enable internal pull-ups for SDMMC1 on DHCOM SoM
@ 2020-12-01 10:29 Marek Vasut
  2020-12-01 10:29 ` [PATCH 2/4] ARM: dts: stm32: Disable SDMMC1 CKIN feedback clock Marek Vasut
                   ` (3 more replies)
  0 siblings, 4 replies; 10+ messages in thread
From: Marek Vasut @ 2020-12-01 10:29 UTC (permalink / raw)
  To: u-boot

The default state of SD bus and clock line is logical HI. SD card IO is
open-drain and pulls the bus lines LO. Always enable the SD bus pull ups
to guarantee this behavior on DHCOM SoM. Note that on SoMs with SD bus
voltage level shifter, the pull ups are built into the level shifter,
however that has no negative impact.

Signed-off-by: Marek Vasut <marex@denx.de>
Cc: Patrice Chotard <patrice.chotard@st.com>
Cc: Patrick Delaunay <patrick.delaunay@st.com>
---
 arch/arm/dts/stm32mp15xx-dhcom.dtsi | 14 ++++++++++++++
 1 file changed, 14 insertions(+)

diff --git a/arch/arm/dts/stm32mp15xx-dhcom.dtsi b/arch/arm/dts/stm32mp15xx-dhcom.dtsi
index f022d8395c..9049245c5b 100644
--- a/arch/arm/dts/stm32mp15xx-dhcom.dtsi
+++ b/arch/arm/dts/stm32mp15xx-dhcom.dtsi
@@ -339,6 +339,20 @@
 	status = "okay";
 };
 
+&sdmmc1_b4_pins_a {
+	/*
+	 * SD bus pull-up resistors:
+	 * - optional on SoMs with SD voltage translator
+	 * - mandatory on SoMs without SD voltage translator
+	 */
+	pins1 {
+		bias-pull-up;
+	};
+	pins2 {
+		bias-pull-up;
+	};
+};
+
 &sdmmc2 {
 	pinctrl-names = "default";
 	pinctrl-0 = <&sdmmc2_b4_pins_a &sdmmc2_d47_pins_a>;
-- 
2.29.2

^ permalink raw reply related	[flat|nested] 10+ messages in thread

end of thread, other threads:[~2020-12-09  9:16 UTC | newest]

Thread overview: 10+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2020-12-01 10:29 [PATCH 1/4] ARM: dts: stm32: Enable internal pull-ups for SDMMC1 on DHCOM SoM Marek Vasut
2020-12-01 10:29 ` [PATCH 2/4] ARM: dts: stm32: Disable SDMMC1 CKIN feedback clock Marek Vasut
     [not found]   ` <ca080b136e214a3285da43b8fb044170@SFHDAG2NODE3.st.com>
2020-12-08 17:25     ` Patrick DELAUNAY
2020-12-01 10:29 ` [PATCH 3/4] ARM: dts: stm32: Enable SDMMC3 on DH DRC02 Marek Vasut
     [not found]   ` <875394241555405484677722aa0f3c05@SFHDAG2NODE3.st.com>
2020-12-08 17:25     ` Patrick DELAUNAY
2020-12-01 10:29 ` [PATCH 4/4] ARM: dts: stm32: Add USB OTG ID pin on DH AV96 Marek Vasut
     [not found]   ` <c12ca0ecdaea4dc8958d82286d7a6073@SFHDAG2NODE3.st.com>
2020-12-08 17:20     ` Patrick DELAUNAY
     [not found] ` <22668d9b2add43d5bb75f50862baf2f6@SFHDAG2NODE3.st.com>
2020-12-08 17:20   ` FW: [PATCH 1/4] ARM: dts: stm32: Enable internal pull-ups for SDMMC1 on DHCOM SoM Patrick DELAUNAY
2020-12-08 17:26     ` Marek Vasut
2020-12-09  9:16       ` Patrick DELAUNAY

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