Patch "mmc: sdhci-of-esdhc: add workaround for pre divider initial value" has been added to the 4.2-stable tree

Patch "mmc: sdhci-of-esdhc: add workaround for pre divider initial value" has been added to the 4.2-stable tree

[gregkh]

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

    mmc: sdhci-of-esdhc: add workaround for pre divider initial value

to the 4.2-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-sdhci-of-esdhc-add-workaround-for-pre-divider-initial-value.patch
and it can be found in the queue-4.2 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 77bd2f6f6c65b4ad259394d416855ed561f21e8f Mon Sep 17 00:00:00 2001
From: Yangbo Lu <yangbo.lu@freescale.com>
Date: Tue, 11 Aug 2015 10:53:34 +0800
Subject: mmc: sdhci-of-esdhc: add workaround for pre divider initial value

From: Yangbo Lu <yangbo.lu@freescale.com>

commit 77bd2f6f6c65b4ad259394d416855ed561f21e8f upstream.

For eSDHC(version < 2.3), the pre divider only could divide base clock
by 2 at least. Add workaround for this to avoid unexpected issue.

Signed-off-by: Yangbo Lu <yangbo.lu@freescale.com>
Acked-by: Joakim Tjernlund <Joakim.Tjernlund@transmode.se>
Fixes: bd455029d01c ("mmc: sdhci-of-esdhc: Pre divider starts at 1")
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
 drivers/mmc/host/sdhci-of-esdhc.c |    6 ++++++
 1 file changed, 6 insertions(+)

--- a/drivers/mmc/host/sdhci-of-esdhc.c
+++ b/drivers/mmc/host/sdhci-of-esdhc.c
@@ -208,6 +208,12 @@ static void esdhc_of_set_clock(struct sd
 	if (clock == 0)
 		return;
 
+	/* Workaround to start pre_div at 2 for VNN < VENDOR_V_23 */
+	temp = esdhc_readw(host, SDHCI_HOST_VERSION);
+	temp = (temp & SDHCI_VENDOR_VER_MASK) >> SDHCI_VENDOR_VER_SHIFT;
+	if (temp < VENDOR_V_23)
+		pre_div = 2;
+
 	/* Workaround to reduce the clock frequency for p1010 esdhc */
 	if (of_find_compatible_node(NULL, NULL, "fsl,p1010-esdhc")) {
 		if (clock > 20000000)


Patches currently in stable-queue which might be from yangbo.lu@freescale.com are

queue-4.2/mmc-sdhci-of-esdhc-add-workaround-for-pre-divider-initial-value.patch