releases/3.18.4/mmc-sdhci-set-sdhci_power_on-with-external-vmmc.patch

From 3cbc6123a93dc91b99b58f7ea37d267fe93e1cad Mon Sep 17 00:00:00 2001
From: Tim Kryger <tim.kryger@gmail.com>
Date: Wed, 14 Jan 2015 07:24:12 +0100
Subject: mmc: sdhci: Set SDHCI_POWER_ON with external vmmc

From: Tim Kryger <tim.kryger@gmail.com>

commit 3cbc6123a93dc91b99b58f7ea37d267fe93e1cad upstream.

Host controllers lacking the required internal vmmc regulator may still
follow the spec with regard to the LSB of SDHCI_POWER_CONTROL.  Set the
SDHCI_POWER_ON bit when vmmc is enabled to encourage the controller to
to drive CMD, DAT, SDCLK.

This fixes a regression observed on some Qualcomm and Nvidia boards
caused by 5222161 mmc: sdhci: Improve external VDD regulator support.

Fixes: 52221610dd84 (mmc: sdhci: Improve external VDD regulator support)
Signed-off-by: Tim Kryger <tim.kryger@gmail.com>
Tested-by: Bjorn Andersson <bjorn.andersson@sonymobile.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

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

--- a/drivers/mmc/host/sdhci.c
+++ b/drivers/mmc/host/sdhci.c
@@ -1239,6 +1239,12 @@ static void sdhci_set_power(struct sdhci
 		spin_unlock_irq(&host->lock);
 		mmc_regulator_set_ocr(mmc, mmc->supply.vmmc, vdd);
 		spin_lock_irq(&host->lock);
+
+		if (mode != MMC_POWER_OFF)
+			sdhci_writeb(host, SDHCI_POWER_ON, SDHCI_POWER_CONTROL);
+		else
+			sdhci_writeb(host, 0, SDHCI_POWER_CONTROL);
+
 		return;
 	}