[U-Boot] [PATCH V2 8/9] mmc: check correctness of the voltage mask in ocr

Stefano Babic sbabic at denx.de
Wed Jan 13 10:50:58 CET 2010


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 at denx.de>
---
 drivers/mmc/mmc.c |   10 +++++++++-
 1 files changed, 9 insertions(+), 1 deletions(-)

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 @@ sd_send_op_cond(struct mmc *mmc)
 
 		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;
-- 
1.6.3.3



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