[PATCH 3.18 116/183] mmc: sdhci: Set SDHCI_POWER_ON with external vmmc

Greg Kroah-Hartman
2015-01-25T18:39:44Z

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;
}