Patch "mmc: sdhci-of-at91: Support external regulators" has been added to the 4.9-stable tree

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

mmc: sdhci-of-at91: Support external regulators

to the 4.9-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-at91-support-external-regulators.patch
and it can be found in the queue-4.9 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree, please let <[email protected]> know about it.

From: Romain Izard <[email protected]>
Date: Thu, 9 Mar 2017 16:18:20 +0100
Subject: mmc: sdhci-of-at91: Support external regulators

From: Romain Izard <[email protected]>

commit 2ce0c7b65505e0d915e99389cced45b478dc935d upstream.

The SDHCI controller in the SAMA5D2 chip requires a valid voltage set in the power control register, otherwise commands will fail with a timeout error.

When using the regulator framework to specify the regulator used by the mmc device, the voltage is not configured, and it is not possible to use the connected device.

Implement a custom 'set_power' function for this specific hardware, that configures the voltage in the register in all cases.

---
 drivers/mmc/host/sdhci-of-at91.c |   19 +++++++++++++++++++
 1 file changed, 19 insertions(+)

@@ -85,11 +85,30 @@ static void sdhci_at91_set_clock(struct
 	sdhci_writew(host, clk, SDHCI_CLOCK_CONTROL);
 }
 
+/*
+ * In this specific implementation of the SDHCI controller, the power register
+ * needs to have a valid voltage set even when the power supply is managed by
+ * an external regulator.
+ */
+static void sdhci_at91_set_power(struct sdhci_host *host, unsigned char mode,
+		     unsigned short vdd)
+{
+	if (!IS_ERR(host->mmc->supply.vmmc)) {
+		struct mmc_host *mmc = host->mmc;
+
+		spin_unlock_irq(&host->lock);
+		mmc_regulator_set_ocr(mmc, mmc->supply.vmmc, vdd);
+		spin_lock_irq(&host->lock);
+	}
+	sdhci_set_power_noreg(host, mode, vdd);
+}
+
 static const struct sdhci_ops sdhci_at91_sama5d2_ops = {
 	.set_clock		= sdhci_at91_set_clock,
 	.set_bus_width		= sdhci_set_bus_width,
 	.reset			= sdhci_reset,
 	.set_uhs_signaling	= sdhci_set_uhs_signaling,
+	.set_power		= sdhci_at91_set_power,
 };
 
 static const struct sdhci_pltfm_data soc_data_sama5d2 = {

Patches currently in stable-queue which might be from [email protected] are

queue-4.9/mmc-sdhci-of-at91-support-external-regulators.patch