ARM: dts: stm32: Enable internal pull-ups for SDMMC1 on DHCOM SoM

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>
Reviewed-by: Patrick Delaunay <patrick.delaunay@foss.st.com>
This commit is contained in:
Marek Vasut 2020-12-01 11:29:17 +01:00 committed by Patrick Delaunay
parent b52b9330c6
commit 845c6720ec

View file

@ -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>;