mmc: sdhci-xenon: add set_power callback

Xenon sdh controller requests proper SD bus voltage select
bits programmed even with vmmc power supply. Any reserved
value(100b-000b) programmed in this field will lead to controller
ignore SD bus power bit and keep its value at zero.
Add set_power callback to handle this.

Signed-off-by: Zhoujie Wu <zjwu@marvell.com>
Acked-by: Adrian Hunter <adrian.hunter@intel.com>
Tested-by: Gregory CLEMENT <gregory.clement@free-electrons.com>
Fixes: 3a3748dba881 ("mmc: sdhci-xenon: Add Marvell Xenon SDHC core functionality")
Cc: <stable@vger.kernel.org>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>

drivers/mmc/host/sdhci-xenon.c

@@ -210,8 +210,27 @@ static void xenon_set_uhs_signaling(struct sdhci_host *host,
 	sdhci_writew(host, ctrl_2, SDHCI_HOST_CONTROL2);
 }
 
+static void xenon_set_power(struct sdhci_host *host, unsigned char mode,
+		unsigned short vdd)
+{
+	struct mmc_host *mmc = host->mmc;
+	u8 pwr = host->pwr;
+
+	sdhci_set_power_noreg(host, mode, vdd);
+
+	if (host->pwr == pwr)
+		return;
+
+	if (host->pwr == 0)
+		vdd = 0;
+
+	if (!IS_ERR(mmc->supply.vmmc))
+		mmc_regulator_set_ocr(mmc, mmc->supply.vmmc, vdd);
+}
+
 static const struct sdhci_ops sdhci_xenon_ops = {
 	.set_clock		= sdhci_set_clock,
+	.set_power		= xenon_set_power,
 	.set_bus_width		= sdhci_set_bus_width,
 	.reset			= xenon_reset,
 	.set_uhs_signaling	= xenon_set_uhs_signaling,