From d9fa4c63f7662c2e0aa8096250072f244f7737f2 Mon Sep 17 00:00:00 2001 From: John Youn Date: Tue, 15 Nov 2016 12:54:15 +0200 Subject: [PATCH] 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 Signed-off-by: Felipe Balbi --- drivers/usb/dwc3/core.c | 4 ++++ drivers/usb/dwc3/core.h | 2 ++ 2 files changed, 6 insertions(+) diff --git a/drivers/usb/dwc3/core.c b/drivers/usb/dwc3/core.c index d024d47c86d1..87d0cfb7b29e 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) diff --git a/drivers/usb/dwc3/core.h b/drivers/usb/dwc3/core.h index 354de247356a..bf63756bc176 100644 --- a/drivers/usb/dwc3/core.h +++ b/drivers/usb/dwc3/core.h @@ -472,6 +472,7 @@ struct dwc3_trb; /** * struct dwc3_event_buffer - Software event buffer representation * @buf: _THE_ buffer + * @cache: The buffer cache used in the threaded interrupt * @length: size of this buffer * @lpos: event offset * @count: cache of last read event count register @@ -481,6 +482,7 @@ struct dwc3_trb; */ struct dwc3_event_buffer { void *buf; + void *cache; unsigned length; unsigned int lpos; unsigned int count; -- 2.45.2