atmel_sdhci: Force card-detect if MMC_CAP_NONREMOVABLE.

If the device attached to the MMC bus is not removable, set force card-detect
bit to bypass card detection procedure, so card detection pin can be used for
other purposes.

It's also a workaround for SAMA5D2 who doesn't drive CMD if using GPIO for card
detection.

Signed-off-by: Zixun LI <zli@ogga.fr>
Reviewed-by: Eugen Hristev <eugen.hristev@collabora.com>

diff --git a/drivers/mmc/atmel_sdhci.c b/drivers/mmc/atmel_sdhci.c
index 37b0bee..5347ba9 100644 (file)
--- a/drivers/mmc/atmel_sdhci.c
+++ b/drivers/mmc/atmel_sdhci.c
@@ -15,6 +15,9 @@
 #define ATMEL_SDHC_MIN_FREQ    400000
 #define ATMEL_SDHC_GCK_RATE    240000000
 
+#define ATMEL_SDHC_MC1R 0x204
+#define ATMEL_SDHC_MC1R_FCD    0x80
+
 #ifndef CONFIG_DM_MMC
 int atmel_sdhci_init(void *regbase, u32 id)
 {
@@ -52,11 +55,37 @@ struct atmel_sdhci_plat {
        struct mmc mmc;
 };
 
+static void atmel_sdhci_config_fcd(struct sdhci_host *host)
+{
+       u8 mc1r;
+
+       /* If nonremovable, assume that the card is always present.
+        *
+        * WA: SAMA5D2 doesn't drive CMD if using CD GPIO line.
+        */
+       if ((host->mmc->cfg->host_caps & MMC_CAP_NONREMOVABLE)
+#if CONFIG_IS_ENABLED(DM_GPIO)
+               || dm_gpio_get_value(&host->cd_gpio) >= 0
+#endif
+          ) {
+               sdhci_readb(host, ATMEL_SDHC_MC1R);
+               mc1r |= ATMEL_SDHC_MC1R_FCD;
+               sdhci_writeb(host, mc1r, ATMEL_SDHC_MC1R);
+       }
+}
+
 static int atmel_sdhci_deferred_probe(struct sdhci_host *host)
 {
        struct udevice *dev = host->mmc->dev;
+       int ret;
 
-       return sdhci_probe(dev);
+       ret = sdhci_probe(dev);
+       if (ret)
+               return ret;
+
+       atmel_sdhci_config_fcd(host);
+
+       return 0;
 }
 
 static const struct sdhci_ops atmel_sdhci_ops = {
@@ -120,7 +149,13 @@ static int atmel_sdhci_probe(struct udevice *dev)
 
        clk_free(&clk);
 
-       return sdhci_probe(dev);
+       ret = sdhci_probe(dev);
+       if (ret)
+               return ret;
+
+       atmel_sdhci_config_fcd(host);
+
+       return 0;
 }
 
 static int atmel_sdhci_bind(struct udevice *dev)