The OCR register defines both acceptable voltage bits, as well as bits

for other things.  Mask out the voltage only bits when returning the
Vdd mask for voltage computation.

Submitted by:	mav@

sys/dev/mmc/mmc.c

@@ -239,8 +239,8 @@ mmc_rescan_cards(struct mmc_softc *sc)
 static uint32_t
 mmc_select_vdd(struct mmc_softc *sc, uint32_t ocr)
 {
-    // XXX
-	return ocr;
+
+	return ocr & MMC_OCR_VOLTAGE;
 }
 
 static int

sys/dev/mmc/mmcreg.h

@@ -292,6 +292,7 @@ struct mmc_request {
  *
  * The MMC_OCR_CCS appears to be valid for only SD cards.
  */
+#define MMC_OCR_VOLTAGE	0x3fffffffU	/* Vdd Voltage mask */
 #define	MMC_OCR_LOW_VOLTAGE (1u << 7)	/* Low Voltage Range -- tbd */
 #define	MMC_OCR_200_210	(1U << 8)	/* Vdd voltage 2.00 ~ 2.10 */
 #define	MMC_OCR_210_220	(1U << 9)	/* Vdd voltage 2.10 ~ 2.20 */