mmc: check correctness of the voltage mask in ocr
Most cards do not answer if some reserved bits
in the ocr are set. However, some controllers
can set bit 7 (reserved for low voltages), but
how to manage low voltages SD card is not yet
specified.
Signed-off-by: Stefano Babic <sbabic@denx.de>
diff --git a/drivers/mmc/mmc.c b/drivers/mmc/mmc.c
index b69ce15..d91b9b7 100644
--- a/drivers/mmc/mmc.c
+++ b/drivers/mmc/mmc.c
@@ -273,7 +273,15 @@
cmd.cmdidx = SD_CMD_APP_SEND_OP_COND;
cmd.resp_type = MMC_RSP_R3;
- cmd.cmdarg = mmc->voltages;
+
+ /*
+ * Most cards do not answer if some reserved bits
+ * in the ocr are set. However, Some controller
+ * can set bit 7 (reserved for low voltages), but
+ * how to manage low voltages SD card is not yet
+ * specified.
+ */
+ cmd.cmdarg = mmc->voltages & 0xff8000;
if (mmc->version == SD_VERSION_2)
cmd.cmdarg |= OCR_HCS;