mmc: stm32_sdmmc2: make reset property optional

Although not recommended, the reset property could be made optional.
This way the driver will probe even if no reset property is provided
in an sdmmc node in DT. This reset is already optional in Linux.

Signed-off-by: Yann Gautier <yann.gautier@foss.st.com>
Reviewed-by: Jaehoon Chung <jh80.chung@samsung.com>
Reviewed-by: Patrice Chotard <patrice.chotard@foss.st.com>
Signed-off-by: Patrick Delaunay <patrick.delaunay@foss.st.com>

diff --git a/drivers/mmc/stm32_sdmmc2.c b/drivers/mmc/stm32_sdmmc2.c
index 44bfc91..81b0760 100644 (file)
--- a/drivers/mmc/stm32_sdmmc2.c
+++ b/drivers/mmc/stm32_sdmmc2.c
@@ -514,10 +514,12 @@ retry_cmd:
  */
 static void stm32_sdmmc2_reset(struct stm32_sdmmc2_priv *priv)
 {
-       /* Reset */
-       reset_assert(&priv->reset_ctl);
-       udelay(2);
-       reset_deassert(&priv->reset_ctl);
+       if (reset_valid(&priv->reset_ctl)) {
+               /* Reset */
+               reset_assert(&priv->reset_ctl);
+               udelay(2);
+               reset_deassert(&priv->reset_ctl);
+       }
 
        /* init the needed SDMMC register after reset */
        writel(priv->pwr_reg_msk, priv->base + SDMMC_POWER);
@@ -735,7 +737,7 @@ static int stm32_sdmmc2_probe(struct udevice *dev)
 
        ret = reset_get_by_index(dev, 0, &priv->reset_ctl);
        if (ret)
-               goto clk_disable;
+               dev_dbg(dev, "No reset provided\n");
 
        gpio_request_by_name(dev, "cd-gpios", 0, &priv->cd_gpio,
                             GPIOD_IS_IN);
@@ -755,8 +757,6 @@ static int stm32_sdmmc2_probe(struct udevice *dev)
        stm32_sdmmc2_reset(priv);
        return 0;
 
-clk_disable:
-       clk_disable(&priv->clk);
 clk_free:
        clk_free(&priv->clk);