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Subject[38/49] usb: musb: fix pm_runtime mismatch
3.2-stable review patch.  If anyone has any objections, please let me know.

------------------
From: Felipe Contreras <felipe.contreras@gmail.com>

commit 772aed45b604c5ff171f0f12c12392d868333f79 upstream.

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[1], but it wasn't triggered in my setup
until 18a2689[2] was merged to Linus' branch at point df0914[3]. IOW;
when PM is working as it was supposed to.

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 in versions before 3.1, but not later (or in it).

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.

[1] usb: musb: Idle path retention and offmode support for OMAP3
[2] OMAP2+: musb: hwmod adaptation for musb registration
[3] Merge branch 'omap-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tmlind/linux-omap-2.6

Cc: Hema HK <hemahk@ti.com>
Signed-off-by: Felipe Contreras <felipe.contreras@gmail.com>
Signed-off-by: Felipe Balbi <balbi@ti.com>

---
drivers/usb/musb/musb_core.c | 2 --
1 file changed, 2 deletions(-)
--- a/drivers/usb/musb/musb_core.c
+++ b/drivers/usb/musb/musb_core.c
@@ -2012,8 +2012,6 @@ musb_init_controller(struct device *dev,
if (status < 0)
goto fail3;

- pm_runtime_put(musb->controller);
-
status = musb_init_debugfs(musb);
if (status < 0)
goto fail4;



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