[PATCH 4.11 44/78] usb: gadget: udc: renesas_usb3: fix pm_runtime functions calling

Greg Kroah-Hartman
2017-06-19T15:22:40Z

From: Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com>

commit cdc876877ebc3f0677b267756d4564e2a429e730 upstream.

This patch fixes an issue that this driver is possible to access
the registers before pm_runtime_get_sync() if a gadget driver is
installed first. After that, oops happens on R-Car Gen3 environment.
To avoid it, this patch changes the pm_runtime call timing from
probe/remove to udc_start/udc_stop.

Fixes: 746bfe63bba3 ("usb: gadget: renesas_usb3: add support for Renesas USB3.0 peripheral controller")
Signed-off-by: Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com>
Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
drivers/usb/gadget/udc/renesas_usb3.c | 12 ++++++------
1 file changed, 6 insertions(+), 6 deletions(-)

--- a/drivers/usb/gadget/udc/renesas_usb3.c
+++ b/drivers/usb/gadget/udc/renesas_usb3.c
@@ -1707,6 +1707,9 @@ static int renesas_usb3_start(struct usb
/* hook up the driver */
usb3->driver = driver;

+ pm_runtime_enable(usb3_to_dev(usb3));
+ pm_runtime_get_sync(usb3_to_dev(usb3));
+
renesas_usb3_init_controller(usb3);

return 0;
@@ -1724,6 +1727,9 @@ static int renesas_usb3_stop(struct usb_
renesas_usb3_stop_controller(usb3);
spin_unlock_irqrestore(&usb3->lock, flags);

+ pm_runtime_put(usb3_to_dev(usb3));
+ pm_runtime_disable(usb3_to_dev(usb3));
+
return 0;
}

@@ -1761,9 +1767,6 @@ static int renesas_usb3_remove(struct pl
{
struct renesas_usb3 *usb3 = platform_get_drvdata(pdev);

- pm_runtime_put(&pdev->dev);
- pm_runtime_disable(&pdev->dev);
-
usb_del_gadget_udc(&usb3->gadget);

__renesas_usb3_ep_free_request(usb3->ep0_req);
@@ -1948,9 +1951,6 @@ static int renesas_usb3_probe(struct pla

usb3->workaround_for_vbus = priv->workaround_for_vbus;

- pm_runtime_enable(&pdev->dev);
- pm_runtime_get_sync(&pdev->dev);
-
dev_info(&pdev->dev, "probed\n");

return 0;