The first attempt to read a register may fail because the clock may not
be enabled, and then the probe of musb driver will fail.
Call clk_prepare_enable() before the first register read.

Signed-off-by: Alexandre Bailon <abai...@baylibre.com>
---
 drivers/usb/musb/da8xx.c | 17 ++++++++---------
 1 file changed, 8 insertions(+), 9 deletions(-)

diff --git a/drivers/usb/musb/da8xx.c b/drivers/usb/musb/da8xx.c
index 210b7e4..6749aa1 100644
--- a/drivers/usb/musb/da8xx.c
+++ b/drivers/usb/musb/da8xx.c
@@ -366,6 +366,12 @@ static int da8xx_musb_init(struct musb *musb)
 
        musb->mregs += DA8XX_MENTOR_CORE_OFFSET;
 
+       ret = clk_prepare_enable(glue->clk);
+       if (ret) {
+               dev_err(glue->dev, "failed to enable clock\n");
+               return ret;
+       }
+
        /* Returns zero if e.g. not clocked */
        rev = musb_readl(reg_base, DA8XX_USB_REVISION_REG);
        if (!rev)
@@ -377,12 +383,6 @@ static int da8xx_musb_init(struct musb *musb)
                goto fail;
        }
 
-       ret = clk_prepare_enable(glue->clk);
-       if (ret) {
-               dev_err(glue->dev, "failed to enable clock\n");
-               goto fail;
-       }
-
        setup_timer(&otg_workaround, otg_timer, (unsigned long)musb);
 
        /* Reset the controller */
@@ -392,7 +392,7 @@ static int da8xx_musb_init(struct musb *musb)
        ret = phy_init(glue->phy);
        if (ret) {
                dev_err(glue->dev, "Failed to init phy.\n");
-               goto err_phy_init;
+               goto fail;
        }
 
        ret = phy_power_on(glue->phy);
@@ -412,9 +412,8 @@ static int da8xx_musb_init(struct musb *musb)
 
 err_phy_power_on:
        phy_exit(glue->phy);
-err_phy_init:
-       clk_disable_unprepare(glue->clk);
 fail:
+       clk_disable_unprepare(glue->clk);
        return ret;
 }
 
-- 
2.7.3

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