[PATCH v8 4/9] usb: dwc3: core: Skip setting event buffers for host only controllers

From: Krishna Kurapati
Date: Sun May 14 2023 - 01:50:55 EST


On some SoC's like SA8295P where the tertiary controller is host-only
capable, GEVTADDRHI/LO, GEVTSIZ, GEVTCOUNT registers are not accessible.
Trying to setup them up during core_init leads to a crash.

For DRD/Peripheral supported controllers, event buffer setup is done
again in gadget_pullup. Skip setup or cleanup of event buffers if
controller is host-only capable.

Signed-off-by: Krishna Kurapati <quic_kriskura@xxxxxxxxxxx>
---
drivers/usb/dwc3/core.c | 10 ++++++++++
1 file changed, 10 insertions(+)

diff --git a/drivers/usb/dwc3/core.c b/drivers/usb/dwc3/core.c
index e983aef1fb93..46192d08d1b6 100644
--- a/drivers/usb/dwc3/core.c
+++ b/drivers/usb/dwc3/core.c
@@ -505,6 +505,11 @@ static int dwc3_alloc_event_buffers(struct dwc3 *dwc, unsigned int length)
int dwc3_event_buffers_setup(struct dwc3 *dwc)
{
struct dwc3_event_buffer *evt;
+ unsigned int hw_mode;
+
+ hw_mode = DWC3_GHWPARAMS0_MODE(dwc->hwparams.hwparams0);
+ if (hw_mode == DWC3_GHWPARAMS0_MODE_HOST)
+ return 0;

evt = dwc->ev_buf;
evt->lpos = 0;
@@ -522,6 +527,11 @@ int dwc3_event_buffers_setup(struct dwc3 *dwc)
void dwc3_event_buffers_cleanup(struct dwc3 *dwc)
{
struct dwc3_event_buffer *evt;
+ unsigned int hw_mode;
+
+ hw_mode = DWC3_GHWPARAMS0_MODE(dwc->hwparams.hwparams0);
+ if (hw_mode == DWC3_GHWPARAMS0_MODE_HOST)
+ return;

evt = dwc->ev_buf;

--
2.40.0