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arm64: dts: ti: k3-am62l3-evm: Disable MMC1 internal pulls on data pins

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AM62L EVM has external 47K pullups on MMC1 DAT1-DAT3 pins [0].
Disable internal pullups on DAT1-DAT3 so that each line has a
single pullup source:
- with both pullups enabled, the effective parallel resistance on
  DAT1-3 (~24.2K) creates a ~2x mismatch vs DAT0 (47K external
  only). Removing internal pullups results in DAT1-3 matching DAT0 at 47K
- 47K external alone is within the recommended range for 1.8V
  signaling (10K min, 50K recommended max)
- both internal and external pullups enabled equals unnecessary power
  consumption

[0] https://www.ti.com/lit/zip/SPRCAL6

Fixes: 00fb4c73b6 ("arm64: dts: ti: k3-am62l: add initial reference board file")
Signed-off-by: Judith Mendez <jm@ti.com>
Reviewed-by: Moteen Shah <m-shah@ti.com>
Link: https://patch.msgid.link/20260223233731.2690472-3-jm@ti.com
Signed-off-by: Vignesh Raghavendra <vigneshr@ti.com>
This commit is contained in:
Judith Mendez 2026-02-23 17:37:30 -06:00 committed by Vignesh Raghavendra
parent 6d4441be96
commit 02532ba563
1 changed files with 3 additions and 3 deletions
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6
arch/arm64/boot/dts/ti/k3-am62l3-evm.dts
View File

@ -272,9 +272,9 @@ mmc1_pins_default: mmc1-default-pins {
AM62LX_IOPAD(0x0230, PIN_INPUT, 0) /* (Y3) MMC1_CMD */
AM62LX_IOPAD(0x0228, PIN_OUTPUT, 0) /* (Y2) MMC1_CLK */
AM62LX_IOPAD(0x0224, PIN_INPUT, 0) /* (AA1) MMC1_DAT0 */
AM62LX_IOPAD(0x0220, PIN_INPUT_PULLUP, 0) /* (Y4) MMC1_DAT1 */
AM62LX_IOPAD(0x021c, PIN_INPUT_PULLUP, 0) /* (AA2) MMC1_DAT2 */
AM62LX_IOPAD(0x0218, PIN_INPUT_PULLUP, 0) /* (AB2) MMC1_DAT3 */
AM62LX_IOPAD(0x0220, PIN_INPUT, 0) /* (Y4) MMC1_DAT1 */
AM62LX_IOPAD(0x021c, PIN_INPUT, 0) /* (AA2) MMC1_DAT2 */
AM62LX_IOPAD(0x0218, PIN_INPUT, 0) /* (AB2) MMC1_DAT3 */
AM62LX_IOPAD(0x0234, PIN_INPUT, 0) /* (B6) MMC1_SDCD */
>;
bootph-all;