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 <dsd@laptop.org>
Reviewed-by: Philip Rakity <prakity@nvidia.com>
Signed-off-by: Chris Ball <cjb@laptop.org>
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 @@
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;