Patch "mmc: core: switch to 1V8 or 1V2 for hs400es mode" has been added to the 4.8-stable tree

Patch "mmc: core: switch to 1V8 or 1V2 for hs400es mode" has been added to the 4.8-stable tree

[gregkh]

This is a note to let you know that I've just added the patch titled

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

to the 4.8-stable tree which can be found at:
    http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
     mmc-core-switch-to-1v8-or-1v2-for-hs400es-mode.patch
and it can be found in the queue-4.8 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@vger.kernel.org> know about it.


>From 1720d3545b772c49b2975eeb3b8f4d3f56dc2085 Mon Sep 17 00:00:00 2001
From: Shawn Lin <shawn.lin@rock-chips.com>
Date: Fri, 30 Sep 2016 14:18:58 +0800
Subject: mmc: core: switch to 1V8 or 1V2 for hs400es mode

From: Shawn Lin <shawn.lin@rock-chips.com>

commit 1720d3545b772c49b2975eeb3b8f4d3f56dc2085 upstream.

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")
Signed-off-by: Shawn Lin <shawn.lin@rock-chips.com>
Reviewed-by: Douglas Anderson <dianders@chromium.org>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

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

--- a/drivers/mmc/core/mmc.c
+++ b/drivers/mmc/core/mmc.c
@@ -1259,6 +1259,16 @@ static int mmc_select_hs400es(struct mmc
 		goto out_err;
 	}
 
+	if (card->mmc_avail_type & EXT_CSD_CARD_TYPE_HS400_1_2V)
+		err = __mmc_set_signal_voltage(host, MMC_SIGNAL_VOLTAGE_120);
+
+	if (err && card->mmc_avail_type & EXT_CSD_CARD_TYPE_HS400_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;


Patches currently in stable-queue which might be from shawn.lin@rock-chips.com are

queue-4.8/mmc-core-switch-to-1v8-or-1v2-for-hs400es-mode.patch