Hi Marek,
From: Marek Vasut <[email protected]>
Sent: mardi 1 décembre 2020 11:29
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 <[email protected]>
Cc: Patrice Chotard <[email protected]>
Cc: Patrick Delaunay <[email protected]>
---
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
Reviewed-by: Patrick Delaunay <[email protected]>
For the serie: the target is next or it is a bugfix for master / v2021.01 ?
Thanks
Patrick
