[PATCH v6 1/2] usb: musb: da8xx: Call earlier clk_prepare_enable()

Alexandre Bailon
2016-11-15T17:42:59Z

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 <abailon@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 2440f88..4fc226c 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