usb: dwc3-msm: Add support for LPM on cable disconnect
Add runtime power management support in the driver which allows
putting the hardware in low power state, turning off LDOs
and releasing wakelock.
This LPM (aka low power state) support is currently added as part
of USB disconnect and wall-charger connect. LPM support would
later be extended to USB bus suspend as well. Also, support for PHY
retention mode and VDD minimization would be added later.
This commit also adds debugfs nodes that can used to simulate
cable connect and disconnects as A or B device. Following are
the nodes:
-->msm_dwc3/id : Boolean value
-->msm_dwc3/bsv : Boolean value
-->msm_dwc3/connect : can be set to enable/disable
User should first update id/bsv values before enabling 'connect'.
dwc3-msm device is parent of dwc3-core and its runtime PM is managed
by dwc3_otg driver which is responsible for the state transitions
based on notifications from DWC3 h/w or ext_xceiver (using PMIC) for
cable connect and disconnect. This change also allows dwc3 gadget and
host to acquire PM count for the case when dwc3-otg is not present -
e.g. host and device only configurations.
Change-Id: Idd9a59c1ffd46bd98228c9fd4441f668b763534d
Signed-off-by: Manu Gautam <mgautam@codeaurora.org>
diff --git a/drivers/usb/dwc3/dwc3_otg.h b/drivers/usb/dwc3/dwc3_otg.h
index 0d8b61b..b60b42a 100644
--- a/drivers/usb/dwc3/dwc3_otg.h
+++ b/drivers/usb/dwc3/dwc3_otg.h
@@ -35,8 +35,9 @@
struct usb_otg otg;
int irq;
void __iomem *regs;
- struct work_struct sm_work;
- struct dwc3_charger *charger;
+ struct work_struct sm_work;
+ struct dwc3_charger *charger;
+ struct dwc3_ext_xceiv *ext_xceiv;
#define ID 0
#define B_SESS_VLD 1
unsigned long inputs;
@@ -73,4 +74,29 @@
/* for external charger driver */
extern int dwc3_set_charger(struct usb_otg *otg, struct dwc3_charger *charger);
+enum dwc3_ext_events {
+ DWC3_EVENT_NONE = 0, /* no change event */
+ DWC3_EVENT_PHY_RESUME, /* PHY has come out of LPM */
+ DWC3_EVENT_XCEIV_STATE, /* XCEIV state (id/bsv) has changed */
+};
+
+enum dwc3_id_state {
+ DWC3_ID_GROUND = 0,
+ DWC3_ID_FLOAT,
+};
+
+/* external transceiver that can perform connect/disconnect monitoring in LPM */
+struct dwc3_ext_xceiv {
+ enum dwc3_id_state id;
+ bool bsv;
+
+ /* to notify OTG about LPM exit event, provided by OTG */
+ void (*notify_ext_events)(struct usb_otg *otg,
+ enum dwc3_ext_events ext_event);
+};
+
+/* for external transceiver driver */
+extern int dwc3_set_ext_xceiv(struct usb_otg *otg,
+ struct dwc3_ext_xceiv *ext_xceiv);
+
#endif /* __LINUX_USB_DWC3_OTG_H */