sdhci-fujitsu: add support for setting the CMD_DAT_DELAY attribute

The Socionext SynQuacer SoC inherits this IP from Fujitsu, but
requires the F_SDH30_CMD_DAT_DELAY bit to be set in the
F_SDH30_ESD_CONTROL control register. So set this bit if the
DT node has the 'fujitsu,cmd-dat-delay-select' property.

Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Acked-by: Adrian Hunter <adrian.hunter@intel.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>

1 files changed, 14 insertions, 0 deletions

diff --git a/drivers/mmc/host/sdhci_f_sdh30.c b/drivers/mmc/host/sdhci_f_sdh30.c
index 111b66f5439b..04ca0d33a521 100644
--- a/drivers/mmc/host/sdhci_f_sdh30.c
+++ b/drivers/mmc/host/sdhci_f_sdh30.c
@@ -13,6 +13,7 @@
 #include <linux/err.h>
 #include <linux/delay.h>
 #include <linux/module.h>
+#include <linux/property.h>
 #include <linux/clk.h>
 
 #include "sdhci-pltfm.h"
@@ -47,6 +48,7 @@ struct f_sdhost_priv {
         struct clk *clk;
         u32 vendor_hs200;
         struct device *dev;
+        bool enable_cmd_dat_delay;
 };
 
 static void sdhci_f_sdh30_soft_voltage_switch(struct sdhci_host *host)
@@ -84,10 +86,19 @@ static unsigned int sdhci_f_sdh30_get_min_clock(struct sdhci_host *host)
 
 static void sdhci_f_sdh30_reset(struct sdhci_host *host, u8 mask)
 {
+        struct f_sdhost_priv *priv = sdhci_priv(host);
+        u32 ctl;
+
         if (sdhci_readw(host, SDHCI_CLOCK_CONTROL) == 0)
                 sdhci_writew(host, 0xBC01, SDHCI_CLOCK_CONTROL);
 
         sdhci_reset(host, mask);
+
+        if (priv->enable_cmd_dat_delay) {
+                ctl = sdhci_readl(host, F_SDH30_ESD_CONTROL);
+                ctl |= F_SDH30_CMD_DAT_DELAY;
+                sdhci_writel(host, ctl, F_SDH30_ESD_CONTROL);
+        }
 }
 
 static const struct sdhci_ops sdhci_f_sdh30_ops = {
@@ -126,6 +137,9 @@ static int sdhci_f_sdh30_probe(struct platform_device *pdev)
         host->quirks2 = SDHCI_QUIRK2_SUPPORT_SINGLE |
                         SDHCI_QUIRK2_TUNING_WORK_AROUND;
 
+        priv->enable_cmd_dat_delay = device_property_read_bool(dev,
+                                                "fujitsu,cmd-dat-delay-select");
+
         ret = mmc_of_parse(host->mmc);
         if (ret)
                 goto err;