mmc: sunxi: support cd-inverted

With CONFIG_DM_MMC the BananaPi does not detect SD cards.

The sunxi device trees use the cd-inverted property to indicate that
the card detect is inverted.

This property is documented in Linux kernel devicetree/bindings/mmc/mmc.txt
The property is not marked as deprecated.

A similar patch was posted by Tuomas but is in status "Changes Requested".
https://patchwork.ozlabs.org/patch/850377/

This patch is a stripped down version of his patch.

Suggested-by: Tuomas Tynkkynen <tuomas@tuxera.com>
Signed-off-by: Heinrich Schuchardt <xypron.glpk@gmx.de>
Acked-by: Maxime Ripard <maxime.ripard@free-electrons.com>
Reviewed-by: Jagan Teki <jagan@openedev.com>

diff --git a/drivers/mmc/sunxi_mmc.c b/drivers/mmc/sunxi_mmc.c
index 4edb4be46c819295e99917e75c143cae489c7258..df6f32850e28e2c210caba5088e816176b12cd56 100644 (file)
--- a/drivers/mmc/sunxi_mmc.c
+++ b/drivers/mmc/sunxi_mmc.c
@@ -30,6 +30,7 @@ struct sunxi_mmc_priv {
        uint32_t *mclkreg;
        unsigned fatal_err;
        struct gpio_desc cd_gpio;       /* Change Detect GPIO */
+       int cd_inverted;                /* Inverted Card Detect */
        struct sunxi_mmc *reg;
        struct mmc_config cfg;
 };
@@ -544,9 +545,11 @@ static int sunxi_mmc_getcd(struct udevice *dev)
 {
        struct sunxi_mmc_priv *priv = dev_get_priv(dev);
 
-       if (dm_gpio_is_valid(&priv->cd_gpio))
-               return dm_gpio_get_value(&priv->cd_gpio);
+       if (dm_gpio_is_valid(&priv->cd_gpio)) {
+               int cd_state = dm_gpio_get_value(&priv->cd_gpio);
 
+               return cd_state ^ priv->cd_inverted;
+       }
        return 1;
 }
 
@@ -610,6 +613,9 @@ static int sunxi_mmc_probe(struct udevice *dev)
                sunxi_gpio_set_pull(cd_pin, SUNXI_GPIO_PULL_UP);
        }
 
+       /* Check if card detect is inverted */
+       priv->cd_inverted = dev_read_bool(dev, "cd-inverted");
+
        upriv->mmc = &plat->mmc;
 
        /* Reset controller */