Commit 481c225c authored by Elson Roy Serrao's avatar Elson Roy Serrao Committed by Greg Kroah-Hartman
Browse files

usb: gadget: Handle function suspend feature selector 



When host sends function suspend feature selector to the device,
inspect the received packet and trigger function suspend or
function resume accordingly. Inspect the remote wakeup bit and
arm the function for remote wakeup if it is wakeup capable. Also
host queries the function wakeup capability  through a get status
request before sending function resume. Handle such requests in
composite layer.

Signed-off-by: default avatarElson Roy Serrao <quic_eserrao@quicinc.com>
Reviewed-by: default avatarThinh Nguyen <Thinh.Nguyen@synopsys.com>
Link: https://lore.kernel.org/r/1679694482-16430-6-git-send-email-quic_eserrao@quicinc.com


Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
parent 92c08a84

drivers/usb/gadget/composite.c

+60 −5
Original line number Diff line number Diff line
@@ -941,6 +941,9 @@ static void reset_config(struct usb_composite_dev *cdev) 
		if (f->disable)

			f->disable(f);



		/* Section 9.1.1.6, disable remote wakeup when device is reset */

		f->func_wakeup_armed = false;



		bitmap_zero(f->endpoints, 32);

	}

	cdev->config = NULL;
@@ -2006,9 +2009,20 @@ composite_setup(struct usb_gadget *gadget, const struct usb_ctrlrequest *ctrl) 
		f = cdev->config->interface[intf];

		if (!f)

			break;

		status = f->get_status ? f->get_status(f) : 0;



		if (f->get_status) {

			status = f->get_status(f);

			if (status < 0)

				break;

		} else {

			/* Set D0 and D1 bits based on func wakeup capability */

			if (f->config->bmAttributes & USB_CONFIG_ATT_WAKEUP) {

				status |= USB_INTRF_STAT_FUNC_RW_CAP;

				if (f->func_wakeup_armed)

					status |= USB_INTRF_STAT_FUNC_RW;

			}

		}



		put_unaligned_le16(status & 0x0000ffff, req->buf);

		break;

	/*
@@ -2030,8 +2044,44 @@ composite_setup(struct usb_gadget *gadget, const struct usb_ctrlrequest *ctrl) 
			if (!f)

				break;

			value = 0;

			if (f->func_suspend)

			if (f->func_suspend) {

				value = f->func_suspend(f, w_index >> 8);

			/* SetFeature(FUNCTION_SUSPEND) */

			} else if (ctrl->bRequest == USB_REQ_SET_FEATURE) {

				if (!(f->config->bmAttributes &

				      USB_CONFIG_ATT_WAKEUP) &&

				     (w_index & USB_INTRF_FUNC_SUSPEND_RW))

					break;



				f->func_wakeup_armed = !!(w_index &

							  USB_INTRF_FUNC_SUSPEND_RW);



				if (w_index & USB_INTRF_FUNC_SUSPEND_LP) {

					if (f->suspend && !f->func_suspended) {

						f->suspend(f);

						f->func_suspended = true;

					}

				/*

				 * Handle cases where host sends function resume

				 * through SetFeature(FUNCTION_SUSPEND) but low power

				 * bit reset

				 */

				} else {

					if (f->resume && f->func_suspended) {

						f->resume(f);

						f->func_suspended = false;

					}

				}

			/* ClearFeature(FUNCTION_SUSPEND) */

			} else if (ctrl->bRequest == USB_REQ_CLEAR_FEATURE) {

				f->func_wakeup_armed = false;



				if (f->resume && f->func_suspended) {

					f->resume(f);

					f->func_suspended = false;

				}

			}



			if (value < 0) {

				ERROR(cdev,

				      "func_suspend() returned error %d\n",
@@ -2573,7 +2623,12 @@ void composite_resume(struct usb_gadget *gadget) 
		cdev->driver->resume(cdev);

	if (cdev->config) {

		list_for_each_entry(f, &cdev->config->functions, list) {

			if (f->resume)

			/*

			 * Check for func_suspended flag to see if the function is

			 * in USB3 FUNCTION_SUSPEND state. In this case resume is

			 * done via FUNCTION_SUSPEND feature selector.

			 */

			if (f->resume && !f->func_suspended)

				f->resume(f);

		}