Hi,
On Wed, Dec 15, 2010 at 04:44:11PM +0530, Pavankumar Kondeti wrote:
OTG supplement revision 2.0 spec introduces Attach Detection Protocol
(ADP) for detecting peripheral connection without applying power on
VBUS. ADP is optional and is included in the OTG descriptor along with
SRP and HNP.
HNP polling is introduced for peripheral to notify its wish to become
host. Host polls (GET_STATUS on DEVICE) peripheral for host_request
and suspend the bus when peripheral returns host_request TRUE. The spec
insists the polling frequency to be in 1-2 sec range and bus should be
suspended with in 2 sec from host_request is set.
within ?
diff --git a/drivers/usb/core/driver.c b/drivers/usb/core/driver.c
index b9278a1..38885b6 100644
--- a/drivers/usb/core/driver.c
+++ b/drivers/usb/core/driver.c
@@ -1207,6 +1207,19 @@ static int usb_suspend_both(struct usb_device *udev, pm_message_t msg)
* and flush any outstanding URBs.
*/
} else {
+#ifdef CONFIG_USB_OTG
+ /* According to OTG supplement Rev 2.0 section 6.3
+ * Unless an A-device enables b_hnp_enable before entering
+ * suspend it shall also continue polling while the bus is
+ * suspended.
+ *
+ * We don't have to perform HNP polling, as we are going to
+ * enable b_hnp_enable before suspending.
+ */
+ if (udev->bus->hnp_support &&
+ udev->portnum == udev->bus->otg_port)
+ cancel_delayed_work(&udev->bus->hnp_polling);
+#endif
udev->can_submit = 0;
for (i = 0; i < 16; ++i) {
usb_hcd_flush_endpoint(udev, udev->ep_out[i]);
@@ -1270,6 +1283,43 @@ static int usb_resume_both(struct usb_device *udev, pm_message_t msg)
return status;
}
+#ifdef CONFIG_USB_OTG
+void usb_hnp_polling_work(struct work_struct *work)
do you really need this to be exported ??
+{
+ int ret;
+ struct usb_bus *bus =
+ container_of(work, struct usb_bus, hnp_polling.work);
+ struct usb_device *udev = bus->root_hub->children[bus->otg_port - 1];
+ u8 *status = kmalloc(sizeof(*status), GFP_KERNEL);
how about:
u8 status;
and...
+ if (!status)
+ return;
+
+ ret = usb_control_msg(udev, usb_rcvctrlpipe(udev, 0),
+ USB_REQ_GET_STATUS, USB_DIR_IN | USB_RECIP_DEVICE,
+ 0, OTG_STATUS_SELECTOR, status, sizeof(*status),
0, OTG_STATUS_SELECTOR, &status, sizeof(status);
??
--
balbi
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