USB: gpio_vbus: avoid consecutive vbus_session calls with the same "is_active" (e44694e8) · Commits · 戴 / test

Basically, ->vbus_session() calls should be served when VBUS session starts and ends (it's not whenever transciever drivers detect VBUS _changes_). Otherwise, if UDC gadget drivers don't want for some reason ->vbus_session() calls with the same "is_active" value, either OTG or UDC drivers need to have some protection handlings. Also, on platforms using this 'gpio_vbus' driver, the driver is only allowed to check whether VBUS is applied. There is no kernel-standard way prepared for UDC gadget drivers to do that. With this in mind, gpio_vbus should try to prevent unnecessary consecutive vbus_session calls being served with the same "in_active" value. Signed-off-by:

Shinya Kuribayashi <shinya.kuribayashi.px@renesas.com> Signed-off-by:

Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/usb/otg/gpio_vbus.c

+10 −2

Original line number	Diff line number	Diff line
		@@ -38,6 +38,7 @@ struct gpio_vbus_data {
		int vbus_draw_enabled;
		unsigned mA;
		struct delayed_work work;
		int vbus;
		};


		@@ -96,18 +97,24 @@ static void gpio_vbus_work(struct work_struct *work)
		struct gpio_vbus_data *gpio_vbus =
		container_of(work, struct gpio_vbus_data, work.work);
		struct gpio_vbus_mach_info *pdata = gpio_vbus->dev->platform_data;
		int gpio, status;
		int gpio, status, vbus;

		if (!gpio_vbus->phy.otg->gadget)
		return;

		vbus = is_vbus_powered(pdata);
		if ((vbus ^ gpio_vbus->vbus) == 0)
		return;
		gpio_vbus->vbus = vbus;

		/* Peripheral controllers which manage the pullup themselves won't have
		* gpio_pullup configured here. If it's configured here, we'll do what
		* isp1301_omap::b_peripheral() does and enable the pullup here... although
		* that may complicate usb_gadget_{,dis}connect() support.
		*/
		gpio = pdata->gpio_pullup;
		if (is_vbus_powered(pdata)) {

		if (vbus) {
		status = USB_EVENT_VBUS;
		gpio_vbus->phy.state = OTG_STATE_B_PERIPHERAL;
		gpio_vbus->phy.last_event = status;
		@@ -195,6 +202,7 @@ static int gpio_vbus_set_peripheral(struct usb_otg *otg,
		dev_dbg(&pdev->dev, "registered gadget '%s'\n", gadget->name);

		/* initialize connection state */
		gpio_vbus->vbus = 0; /* start with disconnected */
		gpio_vbus_irq(irq, pdev);
		return 0;
		}

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