[PATCH 2/5] mmc: core: switch to 1V8 or 1V2 for hs400es mode

From	Shawn Lin <shawn.lin@rock-chips.com>
Newsgroups	linux.kernel
Subject	[PATCH 2/5] mmc: core: switch to 1V8 or 1V2 for hs400es mode
Date	2016-09-21 03:50 +0200
Message-ID	<sjEPD-2rt-7@gated-at.bofh.it> (permalink)
References	<sjEPD-2rt-5@gated-at.bofh.it>
Organization	linux.* mail to news gateway

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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.

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>
---

 drivers/mmc/core/mmc.c | 10 ++++++++++
 1 file changed, 10 insertions(+)

diff --git a/drivers/mmc/core/mmc.c b/drivers/mmc/core/mmc.c
index 3486bc7..3163bb9 100644
--- a/drivers/mmc/core/mmc.c
+++ b/drivers/mmc/core/mmc.c
@@ -1263,6 +1263,16 @@ 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;
-- 
2.3.7

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[PATCH 2/5] mmc: core: switch to 1V8 or 1V2 for hs400es mode Shawn Lin <shawn.lin@rock-chips.com> - 2016-09-21 03:50 +0200
  Re: [PATCH 2/5] mmc: core: switch to 1V8 or 1V2 for hs400es mode Ulf Hansson <ulf.hansson@linaro.org> - 2016-09-22 11:40 +0200

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