[RESEND PATCH 1/3] usb: dwc3: Don't reinitialize core during host bus-suspend/resume

From: Manu Gautam
Date: Wed Sep 27 2017 - 07:20:14 EST


Driver powers-off PHYs and reinitializes DWC3 core and gadget on
resume. While this works fine for gadget mode but in host
mode there is not re-initialization of host stack. Also, resetting
bus as part of bus_suspend/resume is not correct which could affect
(or disconnect) connected devices.
Fix this by not reinitializing core on suspend/resume in host mode
for HOST only and OTG/drd configurations.

Signed-off-by: Manu Gautam <mgautam@xxxxxxxxxxxxxx>
---
drivers/usb/dwc3/core.c | 43 ++++++++++++++++++++-----------------------
1 file changed, 20 insertions(+), 23 deletions(-)

diff --git a/drivers/usb/dwc3/core.c b/drivers/usb/dwc3/core.c
index 03474d3..f75613f 100644
--- a/drivers/usb/dwc3/core.c
+++ b/drivers/usb/dwc3/core.c
@@ -927,6 +927,7 @@ static int dwc3_core_init_mode(struct dwc3 *dwc)

switch (dwc->dr_mode) {
case USB_DR_MODE_PERIPHERAL:
+ dwc->current_dr_role = DWC3_GCTL_PRTCAP_DEVICE;
dwc3_set_prtcap(dwc, DWC3_GCTL_PRTCAP_DEVICE);

if (dwc->usb2_phy)
@@ -942,6 +943,7 @@ static int dwc3_core_init_mode(struct dwc3 *dwc)
}
break;
case USB_DR_MODE_HOST:
+ dwc->current_dr_role = DWC3_GCTL_PRTCAP_HOST;
dwc3_set_prtcap(dwc, DWC3_GCTL_PRTCAP_HOST);

if (dwc->usb2_phy)
@@ -1293,21 +1295,19 @@ static int dwc3_suspend_common(struct dwc3 *dwc)
{
unsigned long flags;

- switch (dwc->dr_mode) {
- case USB_DR_MODE_PERIPHERAL:
- case USB_DR_MODE_OTG:
+ switch (dwc->current_dr_role) {
+ case DWC3_GCTL_PRTCAP_DEVICE:
spin_lock_irqsave(&dwc->lock, flags);
dwc3_gadget_suspend(dwc);
spin_unlock_irqrestore(&dwc->lock, flags);
+ dwc3_core_exit(dwc);
break;
- case USB_DR_MODE_HOST:
+ case DWC3_GCTL_PRTCAP_HOST:
default:
/* do nothing */
break;
}

- dwc3_core_exit(dwc);
-
return 0;
}

@@ -1316,18 +1316,17 @@ static int dwc3_resume_common(struct dwc3 *dwc)
unsigned long flags;
int ret;

- ret = dwc3_core_init(dwc);
- if (ret)
- return ret;
+ switch (dwc->current_dr_role) {
+ case DWC3_GCTL_PRTCAP_DEVICE:
+ ret = dwc3_core_init(dwc);
+ if (ret)
+ return ret;

- switch (dwc->dr_mode) {
- case USB_DR_MODE_PERIPHERAL:
- case USB_DR_MODE_OTG:
spin_lock_irqsave(&dwc->lock, flags);
dwc3_gadget_resume(dwc);
spin_unlock_irqrestore(&dwc->lock, flags);
- /* FALLTHROUGH */
- case USB_DR_MODE_HOST:
+ break;
+ case DWC3_GCTL_PRTCAP_HOST:
default:
/* do nothing */
break;
@@ -1338,7 +1337,7 @@ static int dwc3_resume_common(struct dwc3 *dwc)

static int dwc3_runtime_checks(struct dwc3 *dwc)
{
- switch (dwc->dr_mode) {
+ switch (dwc->current_dr_role) {
case USB_DR_MODE_PERIPHERAL:
case USB_DR_MODE_OTG:
if (dwc->connected)
@@ -1381,12 +1380,11 @@ static int dwc3_runtime_resume(struct device *dev)
if (ret)
return ret;

- switch (dwc->dr_mode) {
- case USB_DR_MODE_PERIPHERAL:
- case USB_DR_MODE_OTG:
+ switch (dwc->current_dr_role) {
+ case DWC3_GCTL_PRTCAP_DEVICE:
dwc3_gadget_process_pending_events(dwc);
break;
- case USB_DR_MODE_HOST:
+ case DWC3_GCTL_PRTCAP_HOST:
default:
/* do nothing */
break;
@@ -1402,13 +1400,12 @@ static int dwc3_runtime_idle(struct device *dev)
{
struct dwc3 *dwc = dev_get_drvdata(dev);

- switch (dwc->dr_mode) {
- case USB_DR_MODE_PERIPHERAL:
- case USB_DR_MODE_OTG:
+ switch (dwc->current_dr_role) {
+ case DWC3_GCTL_PRTCAP_DEVICE:
if (dwc3_runtime_checks(dwc))
return -EBUSY;
break;
- case USB_DR_MODE_HOST:
+ case DWC3_GCTL_PRTCAP_HOST:
default:
/* do nothing */
break;
--
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