usb: dwc3: gadget: get rid of IRQF_ONESHOT

We can make use of bit 31 of the GEVNTSIZ(n)
registers to mask/unmask interrupts from that
particular interrupter.

With that feature, we can easily drop IRQF_ONESHOT
from our driver which makes it possible to
properly change IRQ priorities when using RT
patchset *and* it allows us to make use of the
scheduler to choose the proper time to handle
this IRQ thread.

Signed-off-by: Felipe Balbi <balbi@ti.com>

1 files changed, 13 insertions, 1 deletions

diff --git a/drivers/usb/dwc3/gadget.c b/drivers/usb/dwc3/gadget.c
index 95ef20c5b53b..bdca5a255a1d 100644
--- a/drivers/usb/dwc3/gadget.c
+++ b/drivers/usb/dwc3/gadget.c
@@ -1490,7 +1490,7 @@ static int dwc3_gadget_start(struct usb_gadget *g,
 
         irq = platform_get_irq(to_platform_device(dwc->dev), 0);
         ret = request_threaded_irq(irq, dwc3_interrupt, dwc3_thread_interrupt,
-                        IRQF_SHARED | IRQF_ONESHOT, "dwc3", dwc);
+                        IRQF_SHARED, "dwc3", dwc);
         if (ret) {
                 dev_err(dwc->dev, "failed to request irq #%d --> %d\n",
                                 irq, ret);
@@ -2447,6 +2447,7 @@ static irqreturn_t dwc3_thread_interrupt(int irq, void *_dwc)
         struct dwc3 *dwc = _dwc;
         unsigned long flags;
         irqreturn_t ret = IRQ_NONE;
+        u32 reg;
         int i;
 
         spin_lock_irqsave(&dwc->lock, flags);
@@ -2486,6 +2487,11 @@ static irqreturn_t dwc3_thread_interrupt(int irq, void *_dwc)
                 evt->count = 0;
                 evt->flags &= ~DWC3_EVENT_PENDING;
                 ret = IRQ_HANDLED;
+
+                /* Unmask interrupt */
+                reg = dwc3_readl(dwc->regs, DWC3_GEVNTSIZ(i));
+                reg &= ~DWC3_GEVNTSIZ_INTMASK;
+                dwc3_writel(dwc->regs, DWC3_GEVNTSIZ(i), reg);
         }
 
         spin_unlock_irqrestore(&dwc->lock, flags);
@@ -2497,6 +2503,7 @@ static irqreturn_t dwc3_process_event_buf(struct dwc3 *dwc, u32 buf)
 {
         struct dwc3_event_buffer *evt;
         u32 count;
+        u32 reg;
 
         evt = dwc->ev_buffs[buf];
 
@@ -2508,6 +2515,11 @@ static irqreturn_t dwc3_process_event_buf(struct dwc3 *dwc, u32 buf)
         evt->count = count;
         evt->flags |= DWC3_EVENT_PENDING;
 
+        /* Mask interrupt */
+        reg = dwc3_readl(dwc->regs, DWC3_GEVNTSIZ(buf));
+        reg |= DWC3_GEVNTSIZ_INTMASK;
+        dwc3_writel(dwc->regs, DWC3_GEVNTSIZ(buf), reg);
+
         return IRQ_WAKE_THREAD;
 }