[PATCH] musb: omap2430: do not assume balanced enable()/disable()

From: Andreas Kemnade
Date: Fri Jul 29 2016 - 14:14:32 EST


The code assumes that omap2430_musb_enable() and
omap2430_musb_disable() is called in a balanced way. The
That fact is broken by the fact that musb_init_controller() calls
musb_platform_disable() to switch from unknown state to off state.

That means that phy_power_off() is called first so that
phy->power_count gets -1 and the phy is not enabled on phy_power_on().
In the probably common case of using the phy_twl4030, that
prevents also charging the battery and so makes further
kernel debugging hard.

The patch prevents phy_power_off() from being called when
it is already off.

Signed-off-by: Andreas Kemnade <andreas@xxxxxxxxxxxx>
---
drivers/usb/musb/omap2430.c | 7 ++++---
1 file changed, 4 insertions(+), 3 deletions(-)

diff --git a/drivers/usb/musb/omap2430.c b/drivers/usb/musb/omap2430.c
index aecb934..c7ae117 100644
--- a/drivers/usb/musb/omap2430.c
+++ b/drivers/usb/musb/omap2430.c
@@ -415,9 +415,10 @@ static void omap2430_musb_disable(struct musb *musb)
struct device *dev = musb->controller;
struct omap2430_glue *glue = dev_get_drvdata(dev->parent);

- if (!WARN_ON(!musb->phy))
- phy_power_off(musb->phy);
-
+ if (glue->enabled) {
+ if (!WARN_ON(!musb->phy))
+ phy_power_off(musb->phy);
+ }
if (glue->status != MUSB_UNKNOWN)
omap_control_usb_set_mode(glue->control_otghs,
USB_MODE_DISCONNECT);
--
2.1.4