[3.16.y-ckt stable] Patch "mmc: sdhci-pxav3: Fix SDR50 and DDR50 capabilities for the Armada 38x flavor" has been added to staging queue

[Luis Henriques]

This is a note to let you know that I have just added a patch titled

    mmc: sdhci-pxav3: Fix SDR50 and DDR50 capabilities for the Armada 38x flavor

to the linux-3.16.y-queue branch of the 3.16.y-ckt extended stable tree 
which can be found at:

 http://kernel.ubuntu.com/git?p=ubuntu/linux.git;a=shortlog;h=refs/heads/linux-3.16.y-queue

This patch is scheduled to be released in version 3.16.7-ckt8.

If you, or anyone else, feels it should not be added to this tree, please 
reply to this email.

For more information about the 3.16.y-ckt tree, see
https://wiki.ubuntu.com/Kernel/Dev/ExtendedStable

Thanks.
-Luis

------

>From c930c075f142a983c29df6218fa0076e6433b125 Mon Sep 17 00:00:00 2001
From: Gregory CLEMENT <gregory.clement at free-electrons.com>
Date: Thu, 29 Jan 2015 12:36:24 +0100
Subject: mmc: sdhci-pxav3: Fix SDR50 and DDR50 capabilities for the Armada 38x
 flavor

commit d4b803c559843e3774736e5108cf6331cf75f64c upstream.

According to erratum 'FE-2946959' both SDR50 and DDR50 modes require
specific clock adjustments in SDIO3 Configuration register. However,
this register was not part of the device tree binding. Even if the
binding can (and will) be extended we still need handling the case
where this register was not available. In this case we use the
SDHCI_QUIRK_MISSING_CAPS quirk remove them from the capabilities.

This commit is based on the work done by Marcin Wojtas<mw at semihalf.com>

Fixes: 5491ce3f79ee ("mmc: sdhci-pxav3: add support for the Armada 38x SDHCI controller")
Signed-off-by: Gregory CLEMENT <gregory.clement at free-electrons.com>
Signed-off-by: Marcin Wojtas <mw at semihalf.com>
Signed-off-by: Ulf Hansson <ulf.hansson at linaro.org>
Signed-off-by: Luis Henriques <luis.henriques at canonical.com>
---
 drivers/mmc/host/sdhci-pxav3.c | 17 +++++++++++++++++
 1 file changed, 17 insertions(+)

diff --git a/drivers/mmc/host/sdhci-pxav3.c b/drivers/mmc/host/sdhci-pxav3.c
index 0c2c12b7149a..f6a5aaf7c918 100644
--- a/drivers/mmc/host/sdhci-pxav3.c
+++ b/drivers/mmc/host/sdhci-pxav3.c
@@ -112,6 +112,20 @@ static int mv_conf_mbus_windows(struct platform_device *pdev,
 	return 0;
 }

+static int armada_38x_quirks(struct sdhci_host *host)
+{
+	host->quirks |= SDHCI_QUIRK_MISSING_CAPS;
+	/*
+	 * According to erratum 'FE-2946959' both SDR50 and DDR50
+	 * modes require specific clock adjustments in SDIO3
+	 * Configuration register, if the adjustment is not done,
+	 * remove them from the capabilities.
+	 */
+	host->caps1 = sdhci_readl(host, SDHCI_CAPABILITIES_1);
+	host->caps1 &= ~(SDHCI_SUPPORT_SDR50 | SDHCI_SUPPORT_DDR50);
+	return 0;
+}
+
 static void pxav3_reset(struct sdhci_host *host, u8 mask)
 {
 	struct platform_device *pdev = to_platform_device(mmc_dev(host->mmc));
@@ -310,6 +324,9 @@ static int sdhci_pxav3_probe(struct platform_device *pdev)
 	clk_prepare_enable(clk);

 	if (of_device_is_compatible(np, "marvell,armada-380-sdhci")) {
+		ret = armada_38x_quirks(host);
+		if (ret < 0)
+			goto err_clk_get;
 		ret = mv_conf_mbus_windows(pdev, mv_mbus_dram_info());
 		if (ret < 0)
 			goto err_mbus_win;