Hi,
On Mon, Jan 02, 2023, JaeHun Jung wrote:
> Sometimes very rarely, The count is 0 and the DWC3 flag is set has status.
> It must not have these status. Because, It can make happen interrupt storming
> status.
> So, It have to clean up DWC3_EVENT_PENDING flags set when count is 0.
> It means "There are no interrupts to handle.".
Can you reword to include the explanation from my response [*] and add a
fixes tag to 7441b273388b ("usb: dwc3: gadget: Fix event pending check")
Thanks,
Thinh
[*] https://lore.kernel.org/linux-usb/20230109182813.sle5h34wdgglnlph@xxxxxxxxxxxx/T/#md32deea7e6b3c6d309aadba3d1cd2800d173685e
>
> (struct dwc3_event_buffer *) ev_buf = 0xFFFFFF883DBF1180 (
> (void *) buf = 0xFFFFFFC00DBDD000 = end+0x337D000,
> (void *) cache = 0xFFFFFF8839F54080,
> (unsigned int) length = 0x1000,
> (unsigned int) lpos = 0x0,
> (unsigned int) count = 0x0,
> (unsigned int) flags = 0x00000001,
> (dma_addr_t) dma = 0x00000008BD7D7000,
> (struct dwc3 *) dwc = 0xFFFFFF8839CBC880,
> (u64) android_kabi_reserved1 = 0x0),
>
> (time = 47557628930999, irq = 165, fn = dwc3_interrupt, latency = 0, en = 1),
> (time = 47557628931268, irq = 165, fn = dwc3_interrupt, latency = 0, en = 3),
> (time = 47557628932383, irq = 165, fn = dwc3_interrupt, latency = 0, en = 1),
> (time = 47557628932652, irq = 165, fn = dwc3_interrupt, latency = 0, en = 3),
> (time = 47557628933768, irq = 165, fn = dwc3_interrupt, latency = 0, en = 1),
> (time = 47557628934037, irq = 165, fn = dwc3_interrupt, latency = 0, en = 3),
> (time = 47557628935152, irq = 165, fn = dwc3_interrupt, latency = 0, en = 1),
> (time = 47557628935460, irq = 165, fn = dwc3_interrupt, latency = 0, en = 3),
> (time = 47557628936575, irq = 165, fn = dwc3_interrupt, latency = 0, en = 1),
> (time = 47557628936845, irq = 165, fn = dwc3_interrupt, latency = 0, en = 3),
> (time = 47557628937960, irq = 165, fn = dwc3_interrupt, latency = 0, en = 1),
> (time = 47557628938229, irq = 165, fn = dwc3_interrupt, latency = 0, en = 3),
> (time = 47557628939345, irq = 165, fn = dwc3_interrupt, latency = 0, en = 1),
> (time = 47557628939652, irq = 165, fn = dwc3_interrupt, latency = 0, en = 3),
> (time = 47557628940768, irq = 165, fn = dwc3_interrupt, latency = 0, en = 1),
> (time = 47557628941037, irq = 165, fn = dwc3_interrupt, latency = 0, en = 3),
> (time = 47557628942152, irq = 165, fn = dwc3_interrupt, latency = 0, en = 1),
> (time = 47557628942422, irq = 165, fn = dwc3_interrupt, latency = 0, en = 3),
> (time = 47557628943537, irq = 165, fn = dwc3_interrupt, latency = 0, en = 1),
> (time = 47557628943806, irq = 165, fn = dwc3_interrupt, latency = 0, en = 3),
> (time = 47557628944922, irq = 165, fn = dwc3_interrupt, latency = 0, en = 1),
> (time = 47557628945229, irq = 165, fn = dwc3_interrupt, latency = 0, en = 3),
> (time = 47557628946345, irq = 165, fn = dwc3_interrupt, latency = 0, en = 1),
> (time = 47557628946614, irq = 165, fn = dwc3_interrupt, latency = 0, en = 3),
> (time = 47557628947729, irq = 165, fn = dwc3_interrupt, latency = 0, en = 1),
> (time = 47557628947999, irq = 165, fn = dwc3_interrupt, latency = 0, en = 3),
>
> Signed-off-by: JaeHun Jung <jh0801.jung@xxxxxxxxxxx>
> ---
> drivers/usb/dwc3/gadget.c | 5 ++++-
> 1 file changed, 4 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/usb/dwc3/gadget.c b/drivers/usb/dwc3/gadget.c
> index 789976567f9f..5d2d5a9b9915 100644
> --- a/drivers/usb/dwc3/gadget.c
> +++ b/drivers/usb/dwc3/gadget.c
> @@ -4355,8 +4355,11 @@ static irqreturn_t dwc3_check_event_buf(struct dwc3_event_buffer *evt)
> * irq event handler completes before caching new event to prevent
> * losing events.
> */
> - if (evt->flags & DWC3_EVENT_PENDING)
> + if (evt->flags & DWC3_EVENT_PENDING) {
> + if (!evt->count)
> + evt->flags &= ~DWC3_EVENT_PENDING;
> return IRQ_HANDLED;
> + }
>
> count = dwc3_readl(dwc->regs, DWC3_GEVNTCOUNT(0));
> count &= DWC3_GEVNTCOUNT_MASK;
> --
> 2.31.1
>
