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 e63c6fc..bbbd5f1 100644 --- a/drivers/usb/gadget/udc/atmel_usba_udc.c +++ b/drivers/usb/gadget/udc/atmel_usba_udc.c @@ -1749,10 +1749,6 @@ 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) { @@ -1773,7 +1769,6 @@ static irqreturn_t usba_vbus_irq(int irq, void *devid) udc->vbus_prev = vbus; } -out: spin_unlock(&udc->lock); return IRQ_HANDLED; @@ -2113,6 +2108,8 @@ 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, @@ -2122,8 +2119,6 @@ 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 */ -- 2.1.4 -- To unsubscribe from this list: send the line "unsubscribe linux-usb" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html