Re: [PATCH v4 9/9] usb: dwc3: core: don't break during suspend/resume while we're dual-role

From: Sergei Shtylyov
Date: Thu Sep 03 2015 - 10:14:10 EST

On 09/03/2015 05:10 PM, Roger Quadros wrote:

We can't rely just on dr_mode to decide if we're in host or gadget
mode when we're configured as otg/dual-role. So while dr_mode is
OTG, we find out from the otg state machine if we're in host
or gadget mode and take the necessary actions during suspend/resume.

Also make sure that we disable OTG irq and events during system suspend
so that we don't lockup the system during system suspend/resume.

Signed-off-by: Roger Quadros <rogerq@xxxxxx>
drivers/usb/dwc3/core.c | 27 +++++++++------------------
1 file changed, 9 insertions(+), 18 deletions(-)

diff --git a/drivers/usb/dwc3/core.c b/drivers/usb/dwc3/core.c
index 654aebf..25891e3 100644
--- a/drivers/usb/dwc3/core.c
+++ b/drivers/usb/dwc3/core.c
@@ -1455,18 +1455,15 @@ static int dwc3_suspend(struct device *dev)
dwc->octl = dwc3_readl(dwc->regs, DWC3_OCTL);
dwc->oevt = dwc3_readl(dwc->regs, DWC3_OEVT);
dwc->oevten = dwc3_readl(dwc->regs, DWC3_OEVTEN);
+ dwc3_writel(dwc->regs, DWC3_OEVTEN, 0);
+ disable_irq(dwc->otg_irq);

- switch (dwc->dr_mode) {
+ if (dwc->dr_mode == USB_DR_MODE_PERIPHERAL ||
+ ((dwc->dr_mode == USB_DR_MODE_OTG) && (dwc->fsm->protocol == PROTO_GADGET)))

Hm, you're not very consistent about your parens. :-)

You're right. Should be

if ((dwc->dr_mode == USB_DR_MODE_PERIPHERAL) ||
((dwc->dr_mode == USB_DR_MODE_OTG) && (dwc->fsm->protocol == PROTO_GADGET)))

Parens around == are useless, I'd prefer if you deleted them. But if you'd like to keep them, let it be so. :-)

OK, how about this then?

if (dwc->dr_mode == USB_DR_MODE_PERIPHERAL ||
(dwc->dr_mode == USB_DR_MODE_OTG && dwc->fsm->protocol == PROTO_GADGET))

Strictly speaking, parens around && are also not needed but gcc may probably issue a warning without them. Not sure, your call.


MBR, Sergei

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