USB: gpio_vbus: provide an appropriate debounce interval

In commit c2344f13b5 (USB: gpio_vbus:
add delayed vbus_session calls, 2009-01-24), usb_gadget_vbus_connect()
and ...disconnect() were extracted from the interrupt handler, so to
allow vbus_session handlers to deal with msleep() calls.

This patch takes the approach one step further.

USB2.0 specification (7.1.7.3 Connect and Disconnect Signaling) says
that the USB system software (shall) provide a debounce interval with
a minimum duration of 100 ms, which ensures that the electrical and
mechanical connection is stable before software attempts to reset
the attached device.

Signed-off-by: Shinya Kuribayashi <shinya.kuribayashi.px@renesas.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
Shinya Kuribayashi 2012-05-10 10:31:21 +09:00 committed by Greg Kroah-Hartman
parent 0d13eebcab
commit 934ccec4da

View file

@ -37,7 +37,7 @@ struct gpio_vbus_data {
struct regulator *vbus_draw;
int vbus_draw_enabled;
unsigned mA;
struct work_struct work;
struct delayed_work work;
};
@ -94,7 +94,7 @@ static int is_vbus_powered(struct gpio_vbus_mach_info *pdata)
static void gpio_vbus_work(struct work_struct *work)
{
struct gpio_vbus_data *gpio_vbus =
container_of(work, struct gpio_vbus_data, work);
container_of(work, struct gpio_vbus_data, work.work);
struct gpio_vbus_mach_info *pdata = gpio_vbus->dev->platform_data;
int gpio, status;
@ -152,7 +152,7 @@ static irqreturn_t gpio_vbus_irq(int irq, void *data)
otg->gadget ? otg->gadget->name : "none");
if (otg->gadget)
schedule_work(&gpio_vbus->work);
schedule_delayed_work(&gpio_vbus->work, msecs_to_jiffies(100));
return IRQ_HANDLED;
}
@ -300,7 +300,7 @@ static int __init gpio_vbus_probe(struct platform_device *pdev)
ATOMIC_INIT_NOTIFIER_HEAD(&gpio_vbus->phy.notifier);
INIT_WORK(&gpio_vbus->work, gpio_vbus_work);
INIT_DELAYED_WORK(&gpio_vbus->work, gpio_vbus_work);
gpio_vbus->vbus_draw = regulator_get(&pdev->dev, "vbus_draw");
if (IS_ERR(gpio_vbus->vbus_draw)) {