[PATCH AUTOSEL 4.9 51/98] usb: dwc3: omap: remove IRQ_NOAUTOEN used with shared irq

Sasha Levin
2018-10-25T14:13:36Z

From: Vignesh R <vigneshr@ti.com>

[ Upstream commit ee249b4554947de3be77be4e9e6077b20c0fe055 ]

IRQ_NOAUTOEN cannot be used with shared IRQs, since commit 04c848d39879
("genirq: Warn when IRQ_NOAUTOEN is used with shared interrupts") and
kernel now throws a warn dump. But OMAP DWC3 driver uses this flag. As
per commit 12a7f17fac5b ("usb: dwc3: omap: fix race of pm runtime with
irq handler in probe") that introduced this flag, PM runtime can race
with IRQ handler when deferred probing happens due to extcon,
therefore IRQ_NOAUTOEN needs to be set so that irq is not enabled until
extcon is registered.

Remove setting of IRQ_NOAUTOEN and move the registration of
shared irq to a point after dwc3_omap_extcon_register() and
of_platform_populate(). This avoids possibility of probe deferring and
above said race condition.

Reviewed-by: Grygorii Strashko <grygorii.strashko@ti.com>
Signed-off-by: Vignesh R <vigneshr@ti.com>
Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
drivers/usb/dwc3/dwc3-omap.c | 18 ++++++++----------
1 file changed, 8 insertions(+), 10 deletions(-)

diff --git a/drivers/usb/dwc3/dwc3-omap.c b/drivers/usb/dwc3/dwc3-omap.c
index f221cb479e14..8e69150776f5 100644
--- a/drivers/usb/dwc3/dwc3-omap.c
+++ b/drivers/usb/dwc3/dwc3-omap.c
@@ -512,15 +512,6 @@ static int dwc3_omap_probe(struct platform_device *pdev)

/* check the DMA Status */
reg = dwc3_omap_readl(omap->base, USBOTGSS_SYSCONFIG);
- irq_set_status_flags(omap->irq, IRQ_NOAUTOEN);
- ret = devm_request_threaded_irq(dev, omap->irq, dwc3_omap_interrupt,
- dwc3_omap_interrupt_thread, IRQF_SHARED,
- "dwc3-omap", omap);
- if (ret) {
- dev_err(dev, "failed to request IRQ #%d --> %d\n",
- omap->irq, ret);
- goto err1;
- }

ret = dwc3_omap_extcon_register(omap);
if (ret < 0)
@@ -532,8 +523,15 @@ static int dwc3_omap_probe(struct platform_device *pdev)
goto err2;
}

+ ret = devm_request_threaded_irq(dev, omap->irq, dwc3_omap_interrupt,
+ dwc3_omap_interrupt_thread, IRQF_SHARED,
+ "dwc3-omap", omap);
+ if (ret) {
+ dev_err(dev, "failed to request IRQ #%d --> %d\n",
+ omap->irq, ret);
+ goto err1;
+ }
dwc3_omap_enable_irqs(omap);
- enable_irq(omap->irq);
return 0;

err2:
--
2.17.1