diff mbox series

[v2,6/7] usb: bdc: Halt controller on suspend

Message ID 20200721144326.7976-7-alcooperx@gmail.com (mailing list archive)
State Superseded
Headers show
Series usb: bdc: Updates and fixes to the USB BDC driver | expand

Commit Message

Alan Cooper July 21, 2020, 2:43 p.m. UTC 
From: Danesh Petigara <danesh.petigara@broadcom.com>

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>
---
 drivers/usb/gadget/udc/bdc/bdc_core.c | 9 +++++++--
 1 file changed, 7 insertions(+), 2 deletions(-)

Comments

Florian Fainelli July 21, 2020, 5:34 p.m. UTC | #1 
On 7/21/20 7:43 AM, Al Cooper wrote:
> From: Danesh Petigara <danesh.petigara@broadcom.com>
> 
> 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>
diff mbox series

Patch

diff --git a/drivers/usb/gadget/udc/bdc/bdc_core.c b/drivers/usb/gadget/udc/bdc/bdc_core.c
index 2c2f7aef7ba7..c1650247ea39 100644
--- a/drivers/usb/gadget/udc/bdc/bdc_core.c
+++ b/drivers/usb/gadget/udc/bdc/bdc_core.c
@@ -607,9 +607,14 @@  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)