mmc: sdhci-pxav3: Fix Armada 38x controller's caps according to erratum ERR-7878951

According to erratum 'ERR-7878951' Armada 38x SDHCI controller has
different capabilities than the ones shown in its registers:

- it doesn't support the voltage switching: it can work either with
  3.3V or 1.8V supply
- it doesn't support the SDR104 mode
- SDR50 mode doesn't need tuning

The SDHCI_QUIRK_MISSING_CAPS quirk is used for updating the
capabilities accordingly.

[gregory.clement@free-electrons.com: port from 3.10]

Fixes: 5491ce3f79ee ("mmc: sdhci-pxav3: add support for the Armada 38x SDHCI controller")
Cc: <stable@vger.kernel.org> # v3.15+
Signed-off-by: Gregory CLEMENT <gregory.clement@free-electrons.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>

diff --git a/drivers/mmc/host/sdhci-pxav3.c b/drivers/mmc/host/sdhci-pxav3.c
index 1529efc..90cbf01 100644 (file)
--- a/drivers/mmc/host/sdhci-pxav3.c
+++ b/drivers/mmc/host/sdhci-pxav3.c
@@ -118,8 +118,11 @@ static int mv_conf_mbus_windows(struct platform_device *pdev,
        return 0;
 }
 
-static int armada_38x_quirks(struct sdhci_host *host)
+static int armada_38x_quirks(struct platform_device *pdev,
+                            struct sdhci_host *host)
 {
+       struct device_node *np = pdev->dev.of_node;
+
        host->quirks |= SDHCI_QUIRK_MISSING_CAPS;
        /*
         * According to erratum 'FE-2946959' both SDR50 and DDR50
@@ -129,6 +132,21 @@ static int armada_38x_quirks(struct sdhci_host *host)
         */
        host->caps1 = sdhci_readl(host, SDHCI_CAPABILITIES_1);
        host->caps1 &= ~(SDHCI_SUPPORT_SDR50 | SDHCI_SUPPORT_DDR50);
+
+       /*
+        * According to erratum 'ERR-7878951' Armada 38x SDHCI
+        * controller has different capabilities than the ones shown
+        * in its registers
+        */
+       host->caps = sdhci_readl(host, SDHCI_CAPABILITIES);
+       if (of_property_read_bool(np, "no-1-8-v")) {
+               host->caps &= ~SDHCI_CAN_VDD_180;
+               host->mmc->caps &= ~MMC_CAP_1_8V_DDR;
+       } else {
+               host->caps &= ~SDHCI_CAN_VDD_330;
+       }
+       host->caps1 &= ~(SDHCI_SUPPORT_SDR104 | SDHCI_USE_SDR50_TUNING);
+
        return 0;
 }
 
@@ -332,8 +350,11 @@ static int sdhci_pxav3_probe(struct platform_device *pdev)
        if (!IS_ERR(pxa->clk_core))
                clk_prepare_enable(pxa->clk_core);
 
+       /* enable 1/8V DDR capable */
+       host->mmc->caps |= MMC_CAP_1_8V_DDR;
+
        if (of_device_is_compatible(np, "marvell,armada-380-sdhci")) {
-               ret = armada_38x_quirks(host);
+               ret = armada_38x_quirks(pdev, host);
                if (ret < 0)
                        goto err_clk_get;
                ret = mv_conf_mbus_windows(pdev, mv_mbus_dram_info());
@@ -341,9 +362,6 @@ static int sdhci_pxav3_probe(struct platform_device *pdev)
                        goto err_mbus_win;
        }
 
-       /* enable 1/8V DDR capable */
-       host->mmc->caps |= MMC_CAP_1_8V_DDR;
-
        match = of_match_device(of_match_ptr(sdhci_pxav3_of_match), &pdev->dev);
        if (match) {
                ret = mmc_of_parse(host->mmc);