mmc: sdhci-of-arasan: add sdhci_arasan_voltage_switch for arasan,5.1

[firefly-linux-kernel-4.4.55.git] / drivers / mmc / host / sdhci-of-arasan.c

diff --git a/drivers/mmc/host/sdhci-of-arasan.c b/drivers/mmc/host/sdhci-of-arasan.c
index 243d49e41632d5ba3d344e86301dd01bf92440f9..bce72df479678fa48654d705b2673048e1907640 100644 (file)
--- a/drivers/mmc/host/sdhci-of-arasan.c
+++ b/drivers/mmc/host/sdhci-of-arasan.c
@@ -245,6 +245,28 @@ static void sdhci_arasan_hs400_enhanced_strobe(struct mmc_host *mmc,
        writel(vendor, host->ioaddr + SDHCI_ARASAN_VENDOR_REGISTER);
 }
 
+static int sdhci_arasan_voltage_switch(struct mmc_host *mmc,
+                                      struct mmc_ios *ios)
+{
+       switch (ios->signal_voltage) {
+       case MMC_SIGNAL_VOLTAGE_180:
+               /*
+                * Plese don't switch to 1V8 as arasan,5.1 doesn't
+                * actually refer to this setting to indicate the
+                * signal voltage and the state machine will be broken
+                * actually if we force to enable 1V8. That's something
+                * like broken quirk but we could work around here.
+                */
+               return 0;
+       case MMC_SIGNAL_VOLTAGE_330:
+       case MMC_SIGNAL_VOLTAGE_120:
+               /* We don't support 3V3 and 1V2 */
+               break;
+       }
+
+       return -EINVAL;
+}
+
 static struct sdhci_ops sdhci_arasan_ops = {
        .set_clock = sdhci_arasan_set_clock,
        .get_max_clock = sdhci_pltfm_clk_get_max_clock,
@@ -636,6 +658,8 @@ static int sdhci_arasan_probe(struct platform_device *pdev)
 
                host->mmc_host_ops.hs400_enhanced_strobe =
                                        sdhci_arasan_hs400_enhanced_strobe;
+               host->mmc_host_ops.start_signal_voltage_switch =
+                                       sdhci_arasan_voltage_switch;
        }
 
        ret = sdhci_add_host(host);