From 8ed765aac31b473e1881986d9fe2b6386f49f933 Mon Sep 17 00:00:00 2001 From: Daniel Drake Date: Sun, 25 Nov 2012 13:02:54 -0500 Subject: [PATCH] mmc: dt: add no-1-8-v device tree flag The OLPC XO-1.75 laptop includes a SDHCI controller which is 1.8v capable, and it truthfully reports so in its capabilities. This alternate voltage is used for driving new "UHS-I" SD cards at their full speed. However, what the controller doesn't know is that the motherboard physically doesn't have a 1.8v supply available, so attempting to switch to the 1.8v level will result in a situation that cannot be recovered from without physically replugging the SD card. Add a device tree flag that can be used on systems like these, and hook it up to the equivalent SDHCI quirk. Signed-off-by: Daniel Drake Reviewed-by: Philip Rakity Signed-off-by: Chris Ball --- Documentation/devicetree/bindings/mmc/mmc.txt | 2 ++ drivers/mmc/host/sdhci-pltfm.c | 3 +++ 2 files changed, 5 insertions(+) diff --git a/Documentation/devicetree/bindings/mmc/mmc.txt b/Documentation/devicetree/bindings/mmc/mmc.txt index b96e510..a591c67 100644 --- a/Documentation/devicetree/bindings/mmc/mmc.txt +++ b/Documentation/devicetree/bindings/mmc/mmc.txt @@ -21,6 +21,8 @@ Optional properties: - cd-inverted: when present, polarity on the cd gpio line is inverted - wp-inverted: when present, polarity on the wp gpio line is inverted - max-frequency: maximum operating clock frequency +- no-1-8-v: when present, denotes that 1.8v card voltage is not supported on + this system, even if the controller claims it is. Optional SDIO properties: - keep-power-in-suspend: Preserves card power during a suspend/resume cycle diff --git a/drivers/mmc/host/sdhci-pltfm.c b/drivers/mmc/host/sdhci-pltfm.c index c6c3b12..d4283ef5 100644 --- a/drivers/mmc/host/sdhci-pltfm.c +++ b/drivers/mmc/host/sdhci-pltfm.c @@ -78,6 +78,9 @@ void sdhci_get_of_property(struct platform_device *pdev) if (of_get_property(np, "broken-cd", NULL)) host->quirks |= SDHCI_QUIRK_BROKEN_CARD_DETECTION; + if (of_get_property(np, "no-1-8-v", NULL)) + host->quirks2 |= SDHCI_QUIRK2_NO_1_8_V; + if (of_device_is_compatible(np, "fsl,p2020-rev1-esdhc")) host->quirks |= SDHCI_QUIRK_BROKEN_DMA; -- 2.7.4