[PATCH] usb: musb: fix pm_runtime mismatch

From: Felipe Contreras
Date: Thu Dec 15 2011 - 17:42:28 EST


In musb_init_controller() there's a pm_runtime_put(), but there's no
pm_runtime_get(), which creates a mismatch that causes the driver to
sleep when it shouldn't.

This was introduced in 7acc619, but it wasn't triggered until 18a2689
was merged to Linus' branch at point 6899608.

However, it seems most of the time this is used in a way that keeps the
counter above 0, so nobody noticed. Also, it seems to depend on the
configuration used.

I found the problem by loading isp1704_charger before any usb gadgets:
http://article.gmane.org/gmane.linux.kernel/1226122

All versions after 2.6.39 are affected.

Cc: stable@xxxxxxxxxxxxxxx
Signed-off-by: Felipe Contreras <felipe.contreras@xxxxxxxxx>
---
drivers/usb/musb/musb_core.c | 2 --
1 files changed, 0 insertions(+), 2 deletions(-)

diff --git a/drivers/usb/musb/musb_core.c b/drivers/usb/musb/musb_core.c
index b63ab15..920f04e 100644
--- a/drivers/usb/musb/musb_core.c
+++ b/drivers/usb/musb/musb_core.c
@@ -2012,8 +2012,6 @@ musb_init_controller(struct device *dev, int nIrq, void __iomem *ctrl)
if (status < 0)
goto fail3;

- pm_runtime_put(musb->controller);
-
status = musb_init_debugfs(musb);
if (status < 0)
goto fail4;
--
1.7.8.rc1.14.g248db

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