[PATCH 0/3] ARM: dts: Mark SDIO as non-removable for Exynos Chromebooks

Javier Martinez Canillas javier at osg.samsung.com
Thu Oct 15 03:55:27 PDT 2015


The Exynos based Chromebooks have a Marvell WiFi SDIO chip which is always
present and cannot be detected. The mmc device node is marked as broken-cd
since that property is used in the vendor tree instead of non-removable.

This causes the device to be removed when the system enteres into a suspend
gettings the following warning when the system is resumed:

[  181.944636] mmc2: error -2 during resume (card was removed?)

The rationale for that is explained in commit [0] and it was that using the
non-removable property caused issues with the driver whose reset logic used
the mmc_{remove,add}_host() functions.

But the reset logic in the mwifiex mainline driver has changed and this is
longer the case so it's safe to use non-removable. This series changes the
Snow, Peach Pi and Peach Pit boards to use the correct DT property.

To test, I've cherry picked commit [1] from the vendor tree that adds a
debugfs entry to force a card reset and after the reset, WiFi rescanning works
the card gets connected to an AP and works correctly:

$ echo 1 > /sys/kernel/debug/mwifiex/mlan0/reset

I don't have access to a Snow anymore so testing patch 3/3 on that board will
be appreciated.

[0]: https://chromium.googlesource.com/chromiumos/third_party/kernel/+/ad348e1e2381
[1]: https://chromium.googlesource.com/chromiumos/third_party/kernel/+/5995363523de

Best regards,

Javier Martinez Canillas (3):
  ARM: dts: Mark SDIO as non-removable in exynos5800-peach-pi
  ARM: dts: Mark SDIO as non-removable in exynos5420-peach-pit
  ARM: dts: Mark SDIO as non-removable in exynos5250-snow-common

 arch/arm/boot/dts/exynos5250-snow-common.dtsi | 2 +-
 arch/arm/boot/dts/exynos5420-peach-pit.dts    | 2 +-
 arch/arm/boot/dts/exynos5800-peach-pi.dts     | 2 +-
 3 files changed, 3 insertions(+), 3 deletions(-)


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