usb: dwc3: core: add a event buffer cache
This extra buffer will be used so we can copy
triggered events from our event buffer to this cache
and process all of them later in bottom half
handler.
We need this in order to implement a workaround for
a known erratum in recent DWC3 release.
Signed-off-by: John Youn <johnyoun@synopsys.com>
Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com>
diff --git a/drivers/usb/dwc3/core.c b/drivers/usb/dwc3/core.c
index d024d47..87d0cfb 100644
--- a/drivers/usb/dwc3/core.c
+++ b/drivers/usb/dwc3/core.c
@@ -224,6 +224,10 @@ static struct dwc3_event_buffer *dwc3_alloc_one_event_buffer(struct dwc3 *dwc,
evt->dwc = dwc;
evt->length = length;
+ evt->cache = devm_kzalloc(dwc->dev, length, GFP_KERNEL);
+ if (!evt->cache)
+ return ERR_PTR(-ENOMEM);
+
evt->buf = dma_alloc_coherent(dwc->dev, length,
&evt->dma, GFP_KERNEL);
if (!evt->buf)