[PATCH v4 3/4] mmc: dw_mmc: Use mmc_regulator_set_vqmmc in start_signal_voltage_switch

[dianders@chromium.org (Doug Anderson)]

We've introduced a new helper in the MMC core:
mmc_regulator_set_vqmmc().  Let's use this in dw_mmc.  Using this new
helper has some advantages:

1. We get the mmc_regulator_set_vqmmc() behavior of trying to match
   VQMMC and VMMC when the signal voltage is 3.3V.  This ensures max
   compatibility.

2. We get rid of a few more warnings when probing unsupported
   voltages.

3. We get rid of some non-dw_mmc specific code in dw_mmc.

Signed-off-by: Doug Anderson <dianders@chromium.org>
Reviewed-by: Andrew Bresticker <abrestic@chromium.org>
---
Changes in v4: None
Changes in v3:
- Continue to check for errors if VQMMC is not an error as per Andrew.

Changes in v2: None

 drivers/mmc/host/dw_mmc.c | 17 ++++++-----------
 1 file changed, 6 insertions(+), 11 deletions(-)

diff --git a/drivers/mmc/host/dw_mmc.c b/drivers/mmc/host/dw_mmc.c
index e2811cf..615d1d9 100644
--- a/drivers/mmc/host/dw_mmc.c
+++ b/drivers/mmc/host/dw_mmc.c
@@ -1214,7 +1214,6 @@ static int dw_mci_switch_voltage(struct mmc_host *mmc, struct mmc_ios *ios)
 	struct dw_mci *host = slot->host;
 	u32 uhs;
 	u32 v18 = SDMMC_UHS_18V << slot->id;
-	int min_uv, max_uv;
 	int ret;
 
 	/*
@@ -1223,22 +1222,18 @@ static int dw_mci_switch_voltage(struct mmc_host *mmc, struct mmc_ios *ios)
 	 * does no harm but you need to set the regulator directly.  Try both.
 	 */
 	uhs = mci_readl(host, UHS_REG);
-	if (ios->signal_voltage == MMC_SIGNAL_VOLTAGE_330) {
-		min_uv = 2700000;
-		max_uv = 3600000;
+	if (ios->signal_voltage == MMC_SIGNAL_VOLTAGE_330)
 		uhs &= ~v18;
-	} else {
-		min_uv = 1700000;
-		max_uv = 1950000;
+	else
 		uhs |= v18;
-	}
+
 	if (!IS_ERR(mmc->supply.vqmmc)) {
-		ret = regulator_set_voltage(mmc->supply.vqmmc, min_uv, max_uv);
+		ret = mmc_regulator_set_vqmmc(mmc, ios);
 
 		if (ret) {
 			dev_dbg(&mmc->class_dev,
-					 "Regulator set error %d: %d - %d\n",
-					 ret, min_uv, max_uv);
+					 "Regulator set error %d - %s V\n",
+					 ret, uhs & v18 ? "1.8" : "3.3");
 			return ret;
 		}
 	}
-- 
2.2.0.rc0.207.ga3a616c