[U-Boot] [RFC 2/3][v4] mmc: SEND_OP_COND considers card capabilities (voltage)

[Raffaele Recalcati]

From: Raffaele Recalcati <raffaele.recalcati at bticino.it>

The first SEND_OP_COND (CMD1) command added is used to ask card capabilities.
After it an AND operation is done between card capabilities and host
capabilities (at the moment only for the voltage field).
Finally the correct value is sent to the MMC, waiting that the card
exits from busy state.

Signed-off-by: Raffaele Recalcati <raffaele.recalcati at bticino.it>
---
 drivers/mmc/mmc.c |   19 +++++++++++++++++--
 include/mmc.h     |    2 ++
 2 files changed, 19 insertions(+), 2 deletions(-)

diff --git a/drivers/mmc/mmc.c b/drivers/mmc/mmc.c
index fc1792a..5bea476 100644
--- a/drivers/mmc/mmc.c
+++ b/drivers/mmc/mmc.c
@@ -351,17 +351,32 @@ sd_send_op_cond(struct mmc *mmc)
 
 int mmc_send_op_cond(struct mmc *mmc)
 {
-	int timeout = 1000;
+	int timeout = 10000;
 	struct mmc_cmd cmd;
 	int err;
 
 	/* Some cards seem to need this */
 	mmc_go_idle(mmc);
 
+	/* Asking to the card its capabilities */
+	cmd.cmdidx = MMC_CMD_SEND_OP_COND;
+	cmd.resp_type = MMC_RSP_R3;
+	cmd.cmdarg = 0;
+	cmd.flags = 0;
+
+	err = mmc_send_cmd(mmc, &cmd, NULL);
+
+	if (err)
+		return err;
+
+	udelay(1000);
+
 	do {
 		cmd.cmdidx = MMC_CMD_SEND_OP_COND;
 		cmd.resp_type = MMC_RSP_R3;
-		cmd.cmdarg = OCR_HCS | mmc->voltages;
+		cmd.cmdarg = ((mmc->voltages &
+			      (cmd.response[0] & OCR_VOLTAGE_MASK)) |
+			      (cmd.response[0] & OCR_ACCESS_MODE));
 		cmd.flags = 0;
 
 		err = mmc_send_cmd(mmc, &cmd, NULL);
diff --git a/include/mmc.h b/include/mmc.h
index 4ee8e1c..d18526d 100644
--- a/include/mmc.h
+++ b/include/mmc.h
@@ -93,6 +93,8 @@
 
 #define OCR_BUSY	0x80000000
 #define OCR_HCS		0x40000000
+#define OCR_VOLTAGE_MASK	0x007FFF80
+#define OCR_ACCESS_MODE		0x60000000
 
 #define MMC_STATUS_MASK		(~0x0206BF7F)
 #define MMC_STATUS_RDY_FOR_DATA (1<<8)
-- 
1.7.0.4