[PATCH V2] mmc: sdhci: check 1.2v IO capability for SDHC host

[Chuanxiao Dong <chuanxiao.dong@intel.com>]

Right now enable 1.2v IO voltage for SDHC is by using vqmmc.
Thus for the host which doesn't have vqmmc, or its vqmmc does
not support 1.2v, directly use MMC_CAP2_HS200 may cause HS200
failure.

So needs to check if vqmmc is able to support 1.2v. If it does
not support, disable 1.2v IO for HS200.

Signed-off-by: Chuanxiao Dong <chuanxiao.dong@intel.com>
---
Changelog V2: rebase this patch, and use IS_ERR to check vqmmc.

 drivers/mmc/host/sdhci.c |    7 ++++++-
 1 file changed, 6 insertions(+), 1 deletion(-)

diff --git a/drivers/mmc/host/sdhci.c b/drivers/mmc/host/sdhci.c
index 4cc2ff9..a23738c 100644
--- a/drivers/mmc/host/sdhci.c
+++ b/drivers/mmc/host/sdhci.c
@@ -3009,8 +3009,13 @@ int sdhci_add_host(struct sdhci_host *host)
 		/* SD3.0: SDR104 is supported so (for eMMC) the caps2
 		 * field can be promoted to support HS200.
 		 */
-		if (!(host->quirks2 & SDHCI_QUIRK2_BROKEN_HS200))
+		if (!(host->quirks2 & SDHCI_QUIRK2_BROKEN_HS200)) {
 			mmc->caps2 |= MMC_CAP2_HS200;
+			if (IS_ERR(mmc->supply.vqmmc) ||
+					!regulator_is_supported_voltage
+					(mmc->supply.vqmmc, 1100000, 1300000))
+				mmc->caps2 &= ~MMC_CAP2_HS200_1_2V_SDR;
+		}
 	} else if (caps[1] & SDHCI_SUPPORT_SDR50)
 		mmc->caps |= MMC_CAP_UHS_SDR50;
 
-- 
1.7.10.4