diff --git a/drivers/usb/dwc3/core.c b/drivers/usb/dwc3/core.c index 8e3c23568faf0d393510591a4eb812ddf79c67ad..384175b3135c6dc5113c14120af4ea77a2bc1514 100644 --- a/drivers/usb/dwc3/core.c +++ b/drivers/usb/dwc3/core.c @@ -388,6 +388,13 @@ static void dwc3_free_event_buffers(struct dwc3 *dwc) static int dwc3_alloc_event_buffers(struct dwc3 *dwc, unsigned length) { struct dwc3_event_buffer *evt; + unsigned int hw_mode; + + hw_mode = DWC3_GHWPARAMS0_MODE(dwc->hwparams.hwparams0); + if (hw_mode == DWC3_GHWPARAMS0_MODE_HOST) { + dwc->ev_buf = NULL; + return 0; + } evt = dwc3_alloc_one_event_buffer(dwc, length); if (IS_ERR(evt)) { @@ -409,6 +416,9 @@ int dwc3_event_buffers_setup(struct dwc3 *dwc) { struct dwc3_event_buffer *evt; + if (!dwc->ev_buf) + return 0; + evt = dwc->ev_buf; evt->lpos = 0; dwc3_writel(dwc->regs, DWC3_GEVNTADRLO(0), @@ -425,6 +435,17 @@ int dwc3_event_buffers_setup(struct dwc3 *dwc) void dwc3_event_buffers_cleanup(struct dwc3 *dwc) { struct dwc3_event_buffer *evt; + u32 reg; + + if (!dwc->ev_buf) + return; + /* + * Exynos platforms may not be able to access event buffer if the + * controller failed to halt on dwc3_core_exit(). + */ + reg = dwc3_readl(dwc->regs, DWC3_DSTS); + if (!(reg & DWC3_DSTS_DEVCTRLHLT)) + return; evt = dwc->ev_buf;