fsl_esdhc: Fix the voltage validation process

The current code use all the voltage range support by the host
controller to do the validation.  This will cause problem when
the host supports Low Voltage Range.  Change the validation
voltage to be based on board setup.
Signed-off-by: NLi Yang <leoli@freescale.com>
Tested-by: NStefano Babic <sbabic@denx.de>
Signed-off-by: NKumar Gala <galak@kernel.crashing.org>

drivers/mmc/fsl_esdhc.c

@@ -444,7 +444,7 @@ int fsl_esdhc_initialize(bd_t *bis, struct fsl_esdhc_cfg *cfg)
 {
 	struct fsl_esdhc *regs;
 	struct mmc *mmc;
-	u32 caps;
+	u32 caps, voltage_caps;
 
 	if (!cfg)
 		return -1;
@@ -462,14 +462,24 @@ int fsl_esdhc_initialize(bd_t *bis, struct fsl_esdhc_cfg *cfg)
 	mmc->set_ios = esdhc_set_ios;
 	mmc->init = esdhc_init;
 
+	voltage_caps = 0;
 	caps = regs->hostcapblt;
-
 	if (caps & ESDHC_HOSTCAPBLT_VS18)
-		mmc->voltages |= MMC_VDD_165_195;
+		voltage_caps |= MMC_VDD_165_195;
 	if (caps & ESDHC_HOSTCAPBLT_VS30)
-		mmc->voltages |= MMC_VDD_29_30 | MMC_VDD_30_31;
+		voltage_caps |= MMC_VDD_29_30 | MMC_VDD_30_31;
 	if (caps & ESDHC_HOSTCAPBLT_VS33)
-		mmc->voltages |= MMC_VDD_32_33 | MMC_VDD_33_34;
+		voltage_caps |= MMC_VDD_32_33 | MMC_VDD_33_34;
+
+#ifdef CONFIG_SYS_SD_VOLTAGE
+	mmc->voltages = CONFIG_SYS_SD_VOLTAGE;
+#else
+	mmc->voltages = MMC_VDD_32_33 | MMC_VDD_33_34;
+#endif
+	if ((mmc->voltages & voltage_caps) == 0) {
+		printf("voltage not supported by controller\n");
+		return -1;
+	}
 
 	mmc->host_caps = MMC_MODE_4BIT | MMC_MODE_8BIT;