Le 22/01/2015 17:56, Sylvain Rochet a écrit :
> Vbus IRQ handler needs a started UDC driver to work because it uses
> udc->driver, which is set by the UDC start handler. The previous way
> chosen was to return from interrupt if udc->driver is NULL using a
> spinlock around the check.
>
> We now request an auto disabled (IRQ_NOAUTOEN) Vbus signal IRQ instead
> of an auto enabled IRQ followed by disable_irq(). This way we remove the
> very small timeslot of enabled IRQ which existed previously between
> request() and disable(). We don't need anymore to check if udc->driver
> is NULL in IRQ handler.
>
> Signed-off-by: Sylvain Rochet <sylvain.roc...@finsecur.com>
> Suggested-by: Boris Brezillon <boris.brezil...@free-electrons.com>
> Acked-by: Boris Brezillon <boris.brezil...@free-electrons.com>
Acked-by: Nicolas Ferre <nicolas.fe...@atmel.com>
> ---
> drivers/usb/gadget/udc/atmel_usba_udc.c | 9 ++-------
> 1 file changed, 2 insertions(+), 7 deletions(-)
>
> diff --git a/drivers/usb/gadget/udc/atmel_usba_udc.c
> b/drivers/usb/gadget/udc/atmel_usba_udc.c
> index 40e5fc7..f9f305f 100644
> --- a/drivers/usb/gadget/udc/atmel_usba_udc.c
> +++ b/drivers/usb/gadget/udc/atmel_usba_udc.c
> @@ -1745,10 +1745,6 @@ static irqreturn_t usba_vbus_irq(int irq, void *devid)
>
> spin_lock(&udc->lock);
>
> - /* May happen if Vbus pin toggles during probe() */
> - if (!udc->driver)
> - goto out;
> -
> vbus = vbus_is_present(udc);
> if (vbus != udc->vbus_prev) {
> if (vbus) {
> @@ -1769,7 +1765,6 @@ static irqreturn_t usba_vbus_irq(int irq, void *devid)
> udc->vbus_prev = vbus;
> }
>
> -out:
> spin_unlock(&udc->lock);
>
> return IRQ_HANDLED;
> @@ -2109,6 +2104,8 @@ static int usba_udc_probe(struct platform_device *pdev)
>
> if (gpio_is_valid(udc->vbus_pin)) {
> if (!devm_gpio_request(&pdev->dev, udc->vbus_pin,
> "atmel_usba_udc")) {
> + irq_set_status_flags(gpio_to_irq(udc->vbus_pin),
> + IRQ_NOAUTOEN);
> ret = devm_request_irq(&pdev->dev,
> gpio_to_irq(udc->vbus_pin),
> usba_vbus_irq, 0,
> @@ -2118,8 +2115,6 @@ static int usba_udc_probe(struct platform_device *pdev)
> dev_warn(&udc->pdev->dev,
> "failed to request vbus irq; "
> "assuming always on\n");
> - } else {
> - disable_irq(gpio_to_irq(udc->vbus_pin));
> }
> } else {
> /* gpio_request fail so use -EINVAL for gpio_is_valid */
>
--
Nicolas Ferre
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