Re: [PATCH v3 1/3] arm: dts: rk3288-tinker.dtsi: Fix SD card detection

Am Samstag, 9. März 2019, 16:39:21 CET schrieb David Summers:

The Problem:

On ASUS Tinker Board S, when booting from the eMMC, and there is card
in the sd slot, there are constant errors.

Also when warm reboot, uboot can not access the sd slot

Cause:

Identified by Robin Murphy @ ARM. The Card Detect on rk3288
devices is pulled up by vccio-sd; so when the regulator powers this
off, card detect gives spurious errors. A second problem, is during
power down, vccio-sd apprears to be powered down. This causes a
problem when warm rebooting from the sd card. This was identified by
Jonas Karlman.

History:

A common fault on these rk3288 board, which impliment the reference
design.

When this arose before:

http://lists.infradead.org/pipermail/linux-arm-kernel/2014-August/281153.htm
l

And Ulf and Jaehoon clearly said this was a broken card detect design,
which should be solved via polling

Solution:

Hence broken-cd is set as a property. This cures the errors. The
powering down of vccio-sd during reboot is cured by adding
regulator-boot-on.

This solutions has been fairly widely reviewed and tested.

Signed-off-by: David Summers <redacted>
Reviewed by: Robin Murphy [off-list ref]
Reviewed by: Jonas Karlman [off-list ref]
Test by: TheSaint @ ArchLinux Arm

applied as fix for 5.1 with the following modifications:
- new subject: "ARM: dts: rockchip: Fix SD card detection on rk3288-tinker"
  to match the subsystem
- adapted Reviewed and Tested tags as collected from involved parties
- added Fixes and Cc-stable tags (pointing to the dtsi-split only to ease
  load of stable maintainers, as hopefully most people will use somewhat
  recent kernels on sbcs]


Heiko