[PATCH AUTOSEL for 4.15 111/124] sdhci: Advertise 2.0v supply on SDIO host controller

From: Sasha Levin
Date: Mon Mar 19 2018 - 18:12:08 EST


From: Andy Shevchenko <andriy.shevchenko@xxxxxxxxxxxxxxx>

[ Upstream commit 2a609abe71ca59e4bd7139e161eaca2144ae6f2e ]

On Intel Edison the Broadcom Wi-Fi card, which is connected to SDIO,
requires 2.0v, while the host, according to Intel Merrifield TRM,
supports 1.8v supply only.

The card announces itself as

mmc2: new ultra high speed DDR50 SDIO card at address 0001

Introduce a custom OCR mask for SDIO host controller on Intel Merrifield
and add a special case to sdhci_set_power_noreg() to override 2.0v supply
by enforcing 1.8v power choice.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@xxxxxxxxxxxxxxx>
Acked-by: Adrian Hunter <adrian.hunter@xxxxxxxxx>
Signed-off-by: Ulf Hansson <ulf.hansson@xxxxxxxxxx>
Signed-off-by: Sasha Levin <alexander.levin@xxxxxxxxxxxxx>
---
drivers/mmc/host/sdhci-pci-core.c | 2 ++
drivers/mmc/host/sdhci.c | 7 +++++++
2 files changed, 9 insertions(+)

diff --git a/drivers/mmc/host/sdhci-pci-core.c b/drivers/mmc/host/sdhci-pci-core.c
index bf93e8b0b191..b8fa17a759dd 100644
--- a/drivers/mmc/host/sdhci-pci-core.c
+++ b/drivers/mmc/host/sdhci-pci-core.c
@@ -805,6 +805,8 @@ static int intel_mrfld_mmc_probe_slot(struct sdhci_pci_slot *slot)
slot->host->quirks2 |= SDHCI_QUIRK2_NO_1_8_V;
break;
case INTEL_MRFLD_SDIO:
+ /* Advertise 2.0v for compatibility with the SDIO card's OCR */
+ slot->host->ocr_mask = MMC_VDD_20_21 | MMC_VDD_165_195;
slot->host->mmc->caps |= MMC_CAP_NONREMOVABLE |
MMC_CAP_POWER_OFF_CARD;
break;
diff --git a/drivers/mmc/host/sdhci.c b/drivers/mmc/host/sdhci.c
index d24306b2b839..3a5f305fd442 100644
--- a/drivers/mmc/host/sdhci.c
+++ b/drivers/mmc/host/sdhci.c
@@ -1470,6 +1470,13 @@ void sdhci_set_power_noreg(struct sdhci_host *host, unsigned char mode,
if (mode != MMC_POWER_OFF) {
switch (1 << vdd) {
case MMC_VDD_165_195:
+ /*
+ * Without a regulator, SDHCI does not support 2.0v
+ * so we only get here if the driver deliberately
+ * added the 2.0v range to ocr_avail. Map it to 1.8v
+ * for the purpose of turning on the power.
+ */
+ case MMC_VDD_20_21:
pwr = SDHCI_POWER_180;
break;
case MMC_VDD_29_30:
--
2.14.1