[PATCH] ARM: dts: Bump SD card pin drive strength up on rk3288-evb

Heiko Stübner heiko at sntech.de
Sun Dec 21 06:04:13 PST 2014

Am Mittwoch, 10. Dezember 2014, 12:55:29 schrieb Doug Anderson:
> It seems that ever since (536f6b9 mmc: dw_mmc: Reset DMA before
> enabling IDMAC) landed upstream that SD cards have been very unhappy
> on rk3288-evb.  They were a little unhappy before that change, but
> after that change they're REALLY unhappy.
> It turns out that the above fix happens to fix a corruption when
> reading card information during probe time.  Without the fix we didn't
> detect that high speed SD cards could actually support high speed.
> With the fix we suddenly detect that they're high speed and we try to
> use them at 50MHz.  That doesn't work so well on EVB with the default
> drive strength (maybe because there are two physical SD card slots
> hooked up to the same pin?).
> Fix the problem by bumping up the drive strength of the sdmmc lines.
> Signed-off-by: Doug Anderson <dianders at chromium.org>
> Fixes: 536f6b91d21b ("mmc: dw_mmc: Reset DMA before enabling IDMAC")

applied to my 3.19 dts-fixes branch
(after a slight modification of the subject: please use "ARM: dts: rockchip:")


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