From: Danesh Petigara danesh.petigara@broadcom.com
[ Upstream commit 5fc453d7de3d0c345812453823a3a56783c5f82c ]
GISB bus error kernel panics have been observed during S2 transition tests on the 7271t platform. The errors are a result of the BDC interrupt handler trying to access BDC register space after the system's suspend callbacks have completed.
Adding a suspend hook to the BDC driver that halts the controller before S2 entry thus preventing unwanted access to the BDC register space during this transition.
Signed-off-by: Danesh Petigara danesh.petigara@broadcom.com Signed-off-by: Al Cooper alcooperx@gmail.com Acked-by: Florian Fainelli f.fainelli@gmail.com Signed-off-by: Felipe Balbi balbi@kernel.org Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/usb/gadget/udc/bdc/bdc_core.c | 9 +++++++-- 1 file changed, 7 insertions(+), 2 deletions(-)
diff --git a/drivers/usb/gadget/udc/bdc/bdc_core.c b/drivers/usb/gadget/udc/bdc/bdc_core.c index 5fde5a8b065c1..2dca11f0a7444 100644 --- a/drivers/usb/gadget/udc/bdc/bdc_core.c +++ b/drivers/usb/gadget/udc/bdc/bdc_core.c @@ -603,9 +603,14 @@ static int bdc_remove(struct platform_device *pdev) static int bdc_suspend(struct device *dev) { struct bdc *bdc = dev_get_drvdata(dev); + int ret;
- clk_disable_unprepare(bdc->clk); - return 0; + /* Halt the controller */ + ret = bdc_stop(bdc); + if (!ret) + clk_disable_unprepare(bdc->clk); + + return ret; }
static int bdc_resume(struct device *dev)