[PATCH v13 2/6] usb: dwc3: Add remote wakeup handling
From: Elson Roy Serrao
Date: Fri Mar 24 2023 - 17:48:30 EST
An usb device can initate a remote wakeup and bring the link out of
suspend as dictated by the DEVICE_REMOTE_WAKEUP feature selector.
Add support to handle this packet and set the remote wakeup capability.
Some hosts may take longer time to initiate the resume signaling after
device triggers a remote wakeup. So add async support to the wakeup API
by enabling link status change events.
Acked-by: Thinh Nguyen <Thinh.Nguyen@xxxxxxxxxxxx>
Signed-off-by: Elson Roy Serrao <quic_eserrao@xxxxxxxxxxx>
---
drivers/usb/dwc3/core.h | 2 ++
drivers/usb/dwc3/ep0.c | 7 +++++
drivers/usb/dwc3/gadget.c | 76 +++++++++++++++++++++++++++++++++++++++++++----
3 files changed, 79 insertions(+), 6 deletions(-)
diff --git a/drivers/usb/dwc3/core.h b/drivers/usb/dwc3/core.h
index b1bd631..416e0ef 100644
--- a/drivers/usb/dwc3/core.h
+++ b/drivers/usb/dwc3/core.h
@@ -1113,6 +1113,7 @@ struct dwc3_scratchpad_array {
* 3 - Reserved
* @dis_metastability_quirk: set to disable metastability quirk.
* @dis_split_quirk: set to disable split boundary.
+ * @wakeup_configured: set if the device is configured for remote wakeup.
* @imod_interval: set the interrupt moderation interval in 250ns
* increments or 0 to disable.
* @max_cfg_eps: current max number of IN eps used across all USB configs.
@@ -1331,6 +1332,7 @@ struct dwc3 {
unsigned dis_split_quirk:1;
unsigned async_callbacks:1;
+ unsigned wakeup_configured:1;
u16 imod_interval;
diff --git a/drivers/usb/dwc3/ep0.c b/drivers/usb/dwc3/ep0.c
index 61de693..8aa14a5 100644
--- a/drivers/usb/dwc3/ep0.c
+++ b/drivers/usb/dwc3/ep0.c
@@ -356,6 +356,9 @@ static int dwc3_ep0_handle_status(struct dwc3 *dwc,
usb_status |= 1 << USB_DEV_STAT_U1_ENABLED;
if (reg & DWC3_DCTL_INITU2ENA)
usb_status |= 1 << USB_DEV_STAT_U2_ENABLED;
+ } else {
+ usb_status |= dwc->gadget->wakeup_armed <<
+ USB_DEVICE_REMOTE_WAKEUP;
}
break;
@@ -476,6 +479,10 @@ static int dwc3_ep0_handle_device(struct dwc3 *dwc,
switch (wValue) {
case USB_DEVICE_REMOTE_WAKEUP:
+ if (dwc->wakeup_configured)
+ dwc->gadget->wakeup_armed = set;
+ else
+ ret = -EINVAL;
break;
/*
* 9.4.1 says only for SS, in AddressState only for
diff --git a/drivers/usb/dwc3/gadget.c b/drivers/usb/dwc3/gadget.c
index a1ebb30..c322c70 100644
--- a/drivers/usb/dwc3/gadget.c
+++ b/drivers/usb/dwc3/gadget.c
@@ -258,7 +258,7 @@ int dwc3_send_gadget_generic_command(struct dwc3 *dwc, unsigned int cmd,
return ret;
}
-static int __dwc3_gadget_wakeup(struct dwc3 *dwc);
+static int __dwc3_gadget_wakeup(struct dwc3 *dwc, bool async);
/**
* dwc3_send_gadget_ep_cmd - issue an endpoint command
@@ -325,7 +325,7 @@ int dwc3_send_gadget_ep_cmd(struct dwc3_ep *dep, unsigned int cmd,
fallthrough;
case DWC3_LINK_STATE_U3:
- ret = __dwc3_gadget_wakeup(dwc);
+ ret = __dwc3_gadget_wakeup(dwc, false);
dev_WARN_ONCE(dwc->dev, ret, "wakeup failed --> %d\n",
ret);
break;
@@ -2269,6 +2269,22 @@ static const struct usb_ep_ops dwc3_gadget_ep_ops = {
/* -------------------------------------------------------------------------- */
+static void dwc3_gadget_enable_linksts_evts(struct dwc3 *dwc, bool set)
+{
+ u32 reg;
+
+ if (DWC3_VER_IS_PRIOR(DWC3, 250A))
+ return;
+
+ reg = dwc3_readl(dwc->regs, DWC3_DEVTEN);
+ if (set)
+ reg |= DWC3_DEVTEN_ULSTCNGEN;
+ else
+ reg &= ~DWC3_DEVTEN_ULSTCNGEN;
+
+ dwc3_writel(dwc->regs, DWC3_DEVTEN, reg);
+}
+
static int dwc3_gadget_get_frame(struct usb_gadget *g)
{
struct dwc3 *dwc = gadget_to_dwc(g);
@@ -2276,7 +2292,7 @@ static int dwc3_gadget_get_frame(struct usb_gadget *g)
return __dwc3_gadget_get_frame(dwc);
}
-static int __dwc3_gadget_wakeup(struct dwc3 *dwc)
+static int __dwc3_gadget_wakeup(struct dwc3 *dwc, bool async)
{
int retries;
@@ -2307,9 +2323,13 @@ static int __dwc3_gadget_wakeup(struct dwc3 *dwc)
return -EINVAL;
}
+ if (async)
+ dwc3_gadget_enable_linksts_evts(dwc, true);
+
ret = dwc3_gadget_set_link_state(dwc, DWC3_LINK_STATE_RECOV);
if (ret < 0) {
dev_err(dwc->dev, "failed to put link in Recovery\n");
+ dwc3_gadget_enable_linksts_evts(dwc, false);
return ret;
}
@@ -2321,6 +2341,13 @@ static int __dwc3_gadget_wakeup(struct dwc3 *dwc)
dwc3_writel(dwc->regs, DWC3_DCTL, reg);
}
+ /*
+ * Since link status change events are enabled we will receive
+ * an U0 event when wakeup is successful. So bail out.
+ */
+ if (async)
+ return 0;
+
/* poll until Link State changes to ON */
retries = 20000;
@@ -2346,13 +2373,36 @@ static int dwc3_gadget_wakeup(struct usb_gadget *g)
unsigned long flags;
int ret;
+ if (!dwc->wakeup_configured) {
+ dev_err(dwc->dev, "remote wakeup not configured\n");
+ return -EINVAL;
+ }
+
spin_lock_irqsave(&dwc->lock, flags);
- ret = __dwc3_gadget_wakeup(dwc);
+ if (!dwc->gadget->wakeup_armed) {
+ dev_err(dwc->dev, "not armed for remote wakeup\n");
+ spin_unlock_irqrestore(&dwc->lock, flags);
+ return -EINVAL;
+ }
+ ret = __dwc3_gadget_wakeup(dwc, true);
+
spin_unlock_irqrestore(&dwc->lock, flags);
return ret;
}
+static int dwc3_gadget_set_remote_wakeup(struct usb_gadget *g, int set)
+{
+ struct dwc3 *dwc = gadget_to_dwc(g);
+ unsigned long flags;
+
+ spin_lock_irqsave(&dwc->lock, flags);
+ dwc->wakeup_configured = !!set;
+ spin_unlock_irqrestore(&dwc->lock, flags);
+
+ return 0;
+}
+
static int dwc3_gadget_set_selfpowered(struct usb_gadget *g,
int is_selfpowered)
{
@@ -2978,6 +3028,7 @@ static void dwc3_gadget_async_callbacks(struct usb_gadget *g, bool enable)
static const struct usb_gadget_ops dwc3_gadget_ops = {
.get_frame = dwc3_gadget_get_frame,
.wakeup = dwc3_gadget_wakeup,
+ .set_remote_wakeup = dwc3_gadget_set_remote_wakeup,
.set_selfpowered = dwc3_gadget_set_selfpowered,
.pullup = dwc3_gadget_pullup,
.udc_start = dwc3_gadget_start,
@@ -3819,6 +3870,8 @@ static void dwc3_gadget_disconnect_interrupt(struct dwc3 *dwc)
dwc->gadget->speed = USB_SPEED_UNKNOWN;
dwc->setup_packet_pending = false;
+ dwc->gadget->wakeup_armed = false;
+ dwc3_gadget_enable_linksts_evts(dwc, false);
usb_gadget_set_state(dwc->gadget, USB_STATE_NOTATTACHED);
if (dwc->ep0state != EP0_SETUP_PHASE) {
@@ -3912,6 +3965,8 @@ static void dwc3_gadget_reset_interrupt(struct dwc3 *dwc)
reg &= ~DWC3_DCTL_TSTCTRL_MASK;
dwc3_gadget_dctl_write_safe(dwc, reg);
dwc->test_mode = false;
+ dwc->gadget->wakeup_armed = false;
+ dwc3_gadget_enable_linksts_evts(dwc, false);
dwc3_clear_stall_all_ep(dwc);
/* Reset device address to zero */
@@ -4064,7 +4119,7 @@ static void dwc3_gadget_conndone_interrupt(struct dwc3 *dwc)
*/
}
-static void dwc3_gadget_wakeup_interrupt(struct dwc3 *dwc)
+static void dwc3_gadget_wakeup_interrupt(struct dwc3 *dwc, unsigned int evtinfo)
{
/*
* TODO take core out of low power mode when that's
@@ -4076,6 +4131,8 @@ static void dwc3_gadget_wakeup_interrupt(struct dwc3 *dwc)
dwc->gadget_driver->resume(dwc->gadget);
spin_lock(&dwc->lock);
}
+
+ dwc->link_state = evtinfo & DWC3_LINK_STATE_MASK;
}
static void dwc3_gadget_linksts_change_interrupt(struct dwc3 *dwc,
@@ -4157,6 +4214,12 @@ static void dwc3_gadget_linksts_change_interrupt(struct dwc3 *dwc,
}
switch (next) {
+ case DWC3_LINK_STATE_U0:
+ if (dwc->gadget->wakeup_armed) {
+ dwc3_gadget_enable_linksts_evts(dwc, false);
+ dwc3_resume_gadget(dwc);
+ }
+ break;
case DWC3_LINK_STATE_U1:
if (dwc->speed == USB_SPEED_SUPER)
dwc3_suspend_gadget(dwc);
@@ -4225,7 +4288,7 @@ static void dwc3_gadget_interrupt(struct dwc3 *dwc,
dwc3_gadget_conndone_interrupt(dwc);
break;
case DWC3_DEVICE_EVENT_WAKEUP:
- dwc3_gadget_wakeup_interrupt(dwc);
+ dwc3_gadget_wakeup_interrupt(dwc, event->event_info);
break;
case DWC3_DEVICE_EVENT_HIBER_REQ:
if (dev_WARN_ONCE(dwc->dev, !dwc->has_hibernation,
@@ -4473,6 +4536,7 @@ int dwc3_gadget_init(struct dwc3 *dwc)
dwc->gadget->sg_supported = true;
dwc->gadget->name = "dwc3-gadget";
dwc->gadget->lpm_capable = !dwc->usb2_gadget_lpm_disable;
+ dwc->gadget->wakeup_capable = true;
/*
* FIXME We might be setting max_speed to <SUPER, however versions
--
2.7.4