On 10/13/2023 12:55 AM, Wesley Cheng wrote:
Hi Krishna,
On 10/11/2023 3:02 AM, Krishna Kurapati wrote:
This implementation is to fix RAM interface getting stuck during
Synopsys confirmed that the issue is present on all USB3 devices and
as a workaround, suggested to re-initialize device mode.
Signed-off-by: Krishna Kurapati <quic_kriskura@xxxxxxxxxxx>
---
drivers/usb/dwc3/core.c | 20 ++++++++++++++++++++
drivers/usb/dwc3/core.h | 4 ++++
drivers/usb/dwc3/drd.c | 5 +++++
drivers/usb/dwc3/gadget.c | 6 ++++--
4 files changed, 33 insertions(+), 2 deletions(-)
diff --git a/drivers/usb/dwc3/core.c b/drivers/usb/dwc3/core.c
index 44ee8526dc28..d18b81cccdc5 100644
--- a/drivers/usb/dwc3/core.c
+++ b/drivers/usb/dwc3/core.c
@@ -122,6 +122,7 @@ static void __dwc3_set_mode(struct work_struct *work)
unsigned long flags;
int ret;
u32 reg;
+ u8 timeout = 100;
u32 desired_dr_role;
mutex_lock(&dwc->mutex);
@@ -137,6 +138,25 @@ static void __dwc3_set_mode(struct work_struct
*work)
if (!desired_dr_role)
goto out;
+ /*
+ * STAR 5001544 - If cable disconnect doesn't generate
+ * disconnect event in device mode, then re-initialize the
+ * controller.
+ */
+ if ((dwc->cable_disconnected == true) &&
+ (dwc->current_dr_role == DWC3_GCTL_PRTCAP_DEVICE)) {
+ while (dwc->connected == true && timeout != 0) {
+ mdelay(10);
+ timeout--;
+ }
+
+ if (timeout == 0) {
+ dwc3_gadget_soft_disconnect(dwc);
+ udelay(100);
+ dwc3_gadget_soft_connect(dwc);
+ }
+ }
+
if (desired_dr_role == dwc->current_dr_role)
goto out;
diff --git a/drivers/usb/dwc3/core.h b/drivers/usb/dwc3/core.h
index c6c87acbd376..7642330cf608 100644
--- a/drivers/usb/dwc3/core.h
+++ b/drivers/usb/dwc3/core.h
@@ -1355,6 +1355,7 @@ struct dwc3 {
int last_fifo_depth;
int num_ep_resized;
struct dentry *debug_root;
+ bool cable_disconnected;
};
#define INCRX_BURST_MODE 0
@@ -1568,6 +1569,9 @@ void dwc3_event_buffers_cleanup(struct dwc3 *dwc);
int dwc3_core_soft_reset(struct dwc3 *dwc);
+int dwc3_gadget_soft_disconnect(struct dwc3 *dwc);
+int dwc3_gadget_soft_connect(struct dwc3 *dwc);
+
#if IS_ENABLED(CONFIG_USB_DWC3_HOST) ||
IS_ENABLED(CONFIG_USB_DWC3_DUAL_ROLE)
int dwc3_host_init(struct dwc3 *dwc);
void dwc3_host_exit(struct dwc3 *dwc);
diff --git a/drivers/usb/dwc3/drd.c b/drivers/usb/dwc3/drd.c
index 039bf241769a..593c023fc39a 100644
--- a/drivers/usb/dwc3/drd.c
+++ b/drivers/usb/dwc3/drd.c
@@ -446,6 +446,8 @@ static int dwc3_usb_role_switch_set(struct
usb_role_switch *sw,
struct dwc3 *dwc = usb_role_switch_get_drvdata(sw);
u32 mode;
+ dwc->cable_disconnected = false;
+
switch (role) {
case USB_ROLE_HOST:
mode = DWC3_GCTL_PRTCAP_HOST;
@@ -454,6 +456,9 @@ static int dwc3_usb_role_switch_set(struct
usb_role_switch *sw,
mode = DWC3_GCTL_PRTCAP_DEVICE;
break;
default:
+ if (role == USB_ROLE_NONE)
+ dwc->cable_disconnected = true;
+
How do we handle cases where role switch isn't used? (ie extcon or maybe
no cable connection notification at all)
Hi Wesley,
Since I was considering fixing it during disconnect, I made it in role
switch. So no cable connection notification case has been ruled out in
this patch. But yes, extcon is a valid case. Will need to account for it.
Regards,
Krishna,
