From: xiaoyao <xiaoyao@rock-chips.com>
Date: Thu, 22 Sep 2016 09:20:31 +0000 (+0800)
Subject: mmc: core: switch to 1V8 or 1V2 for hs400es mode
X-Git-Tag: firefly_0821_release~1490
X-Git-Url: http://demsky.eecs.uci.edu/git/?a=commitdiff_plain;h=09c5c21b64168183edbac38e7752b7fc5bb0fe9f;p=firefly-linux-kernel-4.4.55.git

mmc: core: switch to 1V8 or 1V2 for hs400es mode

When introducing hs400es, I didn't notice that we haven't
switched voltage to 1V2 or 1V8 for it. That happens to work
as the first controller claiming to support hs400es, arasan(5.1),
which is designed to only support 1V8. So the voltage is fixed to 1V8.
But it actually is wrong, and will not fit for other host controllers.
Let's fix it.

Change-Id: I982bf34b3d305123ab7debd858e60f2454123c24
Fixes: commit 81ac2af65793ecf ("mmc: core: implement enhanced strobe support")
Cc: <stable@vger.kernel.org> 4.4# +
Signed-off-by: Shawn Lin <shawn.lin@rock-chips.com>
Signed-off-by: xiaoyao <xiaoyao@rock-chips.com>
---

diff --git a/drivers/mmc/core/mmc.c b/drivers/mmc/core/mmc.c
index 4fb06dd188c7..ed5d54dd7c4e 100644
--- a/drivers/mmc/core/mmc.c
+++ b/drivers/mmc/core/mmc.c
@@ -1247,6 +1247,16 @@ static int mmc_select_hs400es(struct mmc_card *card)
 		goto out_err;
 	}
 
+	if (card->mmc_avail_type & EXT_CSD_CARD_TYPE_HS200_1_2V)
+		err = __mmc_set_signal_voltage(host, MMC_SIGNAL_VOLTAGE_120);
+
+	if (err && card->mmc_avail_type & EXT_CSD_CARD_TYPE_HS200_1_8V)
+		err = __mmc_set_signal_voltage(host, MMC_SIGNAL_VOLTAGE_180);
+
+	/* If fails try again during next card power cycle */
+	if (err)
+		goto out_err;
+
 	err = mmc_select_bus_width(card);
 	if (err < 0)
 		goto out_err;