[PATCH] mmc: sdhci: Set ocr_avail directly based on vmmc

[Tim Kryger <tim.kryger@linaro.org>]

When an external regulator provides VDD, set ocr_avail directly based on
the supported voltage range.  This allows for the use of regulators that
can't provide exactly 1.8v, 3.0v, or 3.3v and ensures that ocr_avil bits
are only set for supported voltage ranges.  Commit cec2e21 had attempted
to relax the range checks but because it relied on setting capabilities
as an intermediate step, ocr_avail could easily get a bit set that the
host couldn't support.

Signed-off-by: Tim Kryger <tim.kryger@linaro.org>
---
 drivers/mmc/host/sdhci.c |  107 +++++++++++++++++++++++++---------------------
 1 file changed, 58 insertions(+), 49 deletions(-)

diff --git a/drivers/mmc/host/sdhci.c b/drivers/mmc/host/sdhci.c
index 9a79fc4..4d56fbe 100644
--- a/drivers/mmc/host/sdhci.c
+++ b/drivers/mmc/host/sdhci.c
@@ -2769,6 +2769,29 @@ struct sdhci_host *sdhci_alloc_host(struct device *dev,
 
 EXPORT_SYMBOL_GPL(sdhci_alloc_host);
 
+static unsigned int sdhci_get_ocr_avail_from_vmmc(struct sdhci_host *host)
+{
+	unsigned int ocr_avail = 0;
+	struct regulator *vmmc = host->vmmc;
+
+	if (regulator_is_supported_voltage(vmmc, 1650000, 1950000) > 0)
+		ocr_avail |= MMC_VDD_165_195;
+
+	if (regulator_is_supported_voltage(vmmc, 2900000, 3000000) > 0)
+		ocr_avail |= MMC_VDD_29_30;
+
+	if (regulator_is_supported_voltage(vmmc, 3000000, 3100000) > 0)
+		ocr_avail |= MMC_VDD_30_31;
+
+	if (regulator_is_supported_voltage(vmmc, 3200000, 3300000) > 0)
+		ocr_avail |= MMC_VDD_32_33;
+
+	if (regulator_is_supported_voltage(vmmc, 3300000, 3400000) > 0)
+		ocr_avail |= MMC_VDD_33_34;
+
+	return ocr_avail;
+}
+
 int sdhci_add_host(struct sdhci_host *host)
 {
 	struct mmc_host *mmc;
@@ -3063,24 +3086,39 @@ int sdhci_add_host(struct sdhci_host *host)
 		}
 	}
 
-#ifdef CONFIG_REGULATOR
-	/*
-	 * Voltage range check makes sense only if regulator reports
-	 * any voltage value.
-	 */
+	/* If using external regulator, check supported voltage ranges */
 	if (host->vmmc && regulator_get_voltage(host->vmmc) > 0) {
-		ret = regulator_is_supported_voltage(host->vmmc, 2700000,
-			3600000);
-		if ((ret <= 0) || (!(caps[0] & SDHCI_CAN_VDD_330)))
-			caps[0] &= ~SDHCI_CAN_VDD_330;
-		if ((ret <= 0) || (!(caps[0] & SDHCI_CAN_VDD_300)))
-			caps[0] &= ~SDHCI_CAN_VDD_300;
-		ret = regulator_is_supported_voltage(host->vmmc, 1700000,
-			1950000);
-		if ((ret <= 0) || (!(caps[0] & SDHCI_CAN_VDD_180)))
-			caps[0] &= ~SDHCI_CAN_VDD_180;
-	}
-#endif /* CONFIG_REGULATOR */
+		ocr_avail = sdhci_get_ocr_avail_from_vmmc(host);
+	} else {
+		if (caps[0] & SDHCI_CAN_VDD_330)
+			ocr_avail |= MMC_VDD_32_33 | MMC_VDD_33_34;
+		if (caps[0] & SDHCI_CAN_VDD_300)
+			ocr_avail |= MMC_VDD_29_30 | MMC_VDD_30_31;
+		if (caps[0] & SDHCI_CAN_VDD_180)
+			ocr_avail |= MMC_VDD_165_195;
+	}
+
+	if (host->ocr_mask)
+		ocr_avail = host->ocr_mask;
+
+	mmc->ocr_avail = ocr_avail;
+	mmc->ocr_avail_sdio = ocr_avail;
+	if (host->ocr_avail_sdio)
+		mmc->ocr_avail_sdio &= host->ocr_avail_sdio;
+	mmc->ocr_avail_sd = ocr_avail;
+	if (host->ocr_avail_sd)
+		mmc->ocr_avail_sd &= host->ocr_avail_sd;
+	else /* normal SD controllers don't support 1.8V */
+		mmc->ocr_avail_sd &= ~MMC_VDD_165_195;
+	mmc->ocr_avail_mmc = ocr_avail;
+	if (host->ocr_avail_mmc)
+		mmc->ocr_avail_mmc &= host->ocr_avail_mmc;
+
+	if (mmc->ocr_avail == 0) {
+		pr_err("%s: Hardware doesn't report any support voltages.\n",
+		       mmc_hostname(mmc));
+		return -ENODEV;
+	}
 
 	/*
 	 * According to SD Host Controller spec v3.00, if the Host System
@@ -3106,52 +3144,23 @@ int sdhci_add_host(struct sdhci_host *host)
 		}
 	}
 
-	if (caps[0] & SDHCI_CAN_VDD_330) {
-		ocr_avail |= MMC_VDD_32_33 | MMC_VDD_33_34;
-
+	if (ocr_avail & (MMC_VDD_32_33 | MMC_VDD_33_34))
 		mmc->max_current_330 = ((max_current_caps &
 				   SDHCI_MAX_CURRENT_330_MASK) >>
 				   SDHCI_MAX_CURRENT_330_SHIFT) *
 				   SDHCI_MAX_CURRENT_MULTIPLIER;
-	}
-	if (caps[0] & SDHCI_CAN_VDD_300) {
-		ocr_avail |= MMC_VDD_29_30 | MMC_VDD_30_31;
 
+	if (ocr_avail & (MMC_VDD_29_30 | MMC_VDD_30_31))
 		mmc->max_current_300 = ((max_current_caps &
 				   SDHCI_MAX_CURRENT_300_MASK) >>
 				   SDHCI_MAX_CURRENT_300_SHIFT) *
 				   SDHCI_MAX_CURRENT_MULTIPLIER;
-	}
-	if (caps[0] & SDHCI_CAN_VDD_180) {
-		ocr_avail |= MMC_VDD_165_195;
 
+	if (ocr_avail & MMC_VDD_165_195)
 		mmc->max_current_180 = ((max_current_caps &
 				   SDHCI_MAX_CURRENT_180_MASK) >>
 				   SDHCI_MAX_CURRENT_180_SHIFT) *
 				   SDHCI_MAX_CURRENT_MULTIPLIER;
-	}
-
-	if (host->ocr_mask)
-		ocr_avail = host->ocr_mask;
-
-	mmc->ocr_avail = ocr_avail;
-	mmc->ocr_avail_sdio = ocr_avail;
-	if (host->ocr_avail_sdio)
-		mmc->ocr_avail_sdio &= host->ocr_avail_sdio;
-	mmc->ocr_avail_sd = ocr_avail;
-	if (host->ocr_avail_sd)
-		mmc->ocr_avail_sd &= host->ocr_avail_sd;
-	else /* normal SD controllers don't support 1.8V */
-		mmc->ocr_avail_sd &= ~MMC_VDD_165_195;
-	mmc->ocr_avail_mmc = ocr_avail;
-	if (host->ocr_avail_mmc)
-		mmc->ocr_avail_mmc &= host->ocr_avail_mmc;
-
-	if (mmc->ocr_avail == 0) {
-		pr_err("%s: Hardware doesn't report any "
-			"support voltages.\n", mmc_hostname(mmc));
-		return -ENODEV;
-	}
 
 	spin_lock_init(&host->lock);
 
-- 
1.7.9.5