USB: core: Add support for OTG automated compliance tests

1. Add OTG PET device to TPL. OTG device shall support this
device for allowing compliance automated testing.

2. Add otg_srp_reqd filed to gadget. OTG B-device shall enable
this flag when OTG PET (Protocol and Electrical Tester) that
acts as A-device sends Set Feature TEST_MODE with wIndex high
byte value = 0x06.  OTG PET expects B-device to initiate SRP
after the end of current session.

3. Add otg_vbus_off to usb_bus.  USB core enables this flag
when OTG PET enumerates with bcdDevice[0] field in its Device
Descriptor is equal to 1.  OTG PET expects A-device to turn off
the VBUS with in 5 sec of its disconnection which allows it to
initiate SRP.

3. Add support to identify OTG PET and start HNP quickly.

Change-Id: Ib1f4d835d00ca29ff8f980c94d75a3890507dedc
Signed-off-by: Pavankumar Kondeti <pkondeti@codeaurora.org>
Signed-off-by: Vijayavardhan Vennapusa <vvreddy@codeaurora.org>

drivers/usb/core/hub.c

@@ -1803,6 +1803,7 @@ static int usb_enumerate_device_otg(struct usb_device *udev)
 	int err = 0;
 
 #ifdef	CONFIG_USB_OTG
+	bool old_otg = false;
 	/*
 	 * OTG-aware devices on OTG-capable root hubs may be able to use SRP,
 	 * to wake us after we've powered off VBUS; and HNP, switching roles
@@ -1868,6 +1869,13 @@ static int usb_enumerate_device_otg(struct usb_device *udev)
 		}
 	}
 out:
+	if ((udev->quirks & USB_QUIRK_OTG_PET)) {
+		if (le16_to_cpu(udev->descriptor.bcdDevice) &
+			OTG_TTST_VBUS_OFF)
+			udev->bus->otg_vbus_off = 1;
+		if (udev->bus->is_b_host || old_otg)
+			udev->bus->quick_hnp = 1;
+	}
 
 	if (!is_targeted(udev)) {
 

drivers/usb/core/otg_whitelist.h

@@ -59,6 +59,11 @@ static int is_targeted(struct usb_device *dev)
 	     le16_to_cpu(dev->descriptor.idProduct) == 0xbadd))
 		return 0;
 
+	/* OTG PET device is always targeted (see OTG 2.0 ECN 6.4.2) */
+	if ((le16_to_cpu(dev->descriptor.idVendor) == 0x1a0a &&
+	     le16_to_cpu(dev->descriptor.idProduct) == 0x0200))
+		return 1;
+
 	/* NOTE: can't use usb_match_id() since interface caches
 	 * aren't set up yet. this is cut/paste from that code.
 	 */

drivers/usb/core/quirks.c

@@ -150,6 +150,9 @@ static const struct usb_device_id usb_quirk_list[] = {
 	/* INTEL VALUE SSD */
 	{ USB_DEVICE(0x8086, 0xf1a5), .driver_info = USB_QUIRK_RESET_RESUME },
 
+	/* Protocol and OTG Electrical Test Device */
+	{ USB_DEVICE(0x1a0a, 0x0200), .driver_info = USB_QUIRK_OTG_PET },
+
 	{ }  /* terminating entry must be last */
 };
 

include/linux/usb.h

@@ -332,6 +332,13 @@ struct usb_bus {
 	unsigned is_b_host:1;		/* true during some HNP roleswitches */
 	unsigned b_hnp_enable:1;	/* OTG: did A-Host enable HNP? */
 	unsigned hnp_support:1;		/* OTG: HNP is supported on OTG port */
+	unsigned quick_hnp:1;		/* OTG: Indiacates if hnp is required
+					   irrespective of host_request flag
+					 */
+	unsigned otg_vbus_off:1;	/* OTG: OTG test device feature bit that
+					 * tells A-device to turn off VBUS after
+					 * B-device is disconnected.
+					 */
 	struct delayed_work hnp_polling;/* OTG: HNP polling work */
 	unsigned sg_tablesize;		/* 0 or largest number of sg list entries */
 

include/linux/usb/ch9.h

@@ -134,6 +134,12 @@
 #define	TEST_PACKET	4
 #define	TEST_FORCE_EN	5
 
+/* OTG test mode feature bits
+ * See ECN OTG2.0 spec Table 6-8
+ */
+#define TEST_OTG_SRP_REQD	6
+#define TEST_OTG_HNP_REQD	7
+
 /*
  * New Feature Selectors as added by USB 3.0
  * See USB 3.0 spec Table 9-6
@@ -155,6 +161,9 @@
 #define OTG_STATUS_SELECTOR		0xF000
 #define HOST_REQUEST_FLAG		0
 #define THOST_REQ_POLL			1500    /* msec (1000 - 2000) */
+#define OTG_TTST_SUSP			70	/* msec (0 - 100) */
+
+#define OTG_TTST_VBUS_OFF               1
 
 /* Bit array elements as returned by the USB_REQ_GET_STATUS request. */
 #define USB_DEV_STAT_U1_ENABLED		2	/* transition into U1 state */

include/linux/usb/gadget.h

@@ -500,6 +500,8 @@ struct usb_gadget_ops {
  * @b_hnp_enable: OTG device feature flag, indicating that the A-Host
  *	enabled HNP support.
  * @host_request: A flag set by user when wishes to take up host role.
+ * @otg_srp_reqd: OTG test mode feature to initiate SRP after the end of
+ * current session.
  * @name: Identifies the controller hardware type.  Used in diagnostics
  *	and sometimes configuration.
  * @dev: Driver model state for this abstract device.
@@ -536,6 +538,7 @@ struct usb_gadget {
 	unsigned			a_hnp_support:1;
 	unsigned			a_alt_hnp_support:1;
 	unsigned			host_request:1;
+	unsigned			otg_srp_reqd:1;
 	const char			*name;
 	struct device			dev;
 };

include/linux/usb/quirks.h

@@ -30,4 +30,6 @@
    descriptor */
 #define USB_QUIRK_DELAY_INIT		0x00000040
 
+#define USB_QUIRK_OTG_PET		0x00000080
+
 #endif /* __LINUX_USB_QUIRKS_H */