From mboxrd@z Thu Jan 1 00:00:00 1970 From: nicolas.ferre@atmel.com (Nicolas Ferre) Date: Fri, 23 Jan 2015 09:59:58 +0100 Subject: [PATCHv6 2/5] USB: gadget: atmel_usba_udc: Request an auto disabled Vbus signal IRQ instead of an auto enabled IRQ request followed by IRQ disable In-Reply-To: <0F74BBB2-B515-4A36-8C71-25F58A4D1AB6@jcrosoft.com> References: <1421945805-31129-1-git-send-email-sylvain.rochet@finsecur.com> <1421945805-31129-3-git-send-email-sylvain.rochet@finsecur.com> <0F74BBB2-B515-4A36-8C71-25F58A4D1AB6@jcrosoft.com> Message-ID: <54C20D8E.4040505@atmel.com> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org Le 23/01/2015 08:43, Jean-Christophe PLAGNIOL-VILLARD a ?crit : > >> On Jan 23, 2015, at 12:56 AM, Sylvain Rochet wrote: >> >> 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 >> Suggested-by: Boris Brezillon >> Acked-by: Boris Brezillon >> --- >> 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); > > not happy about still using the broken gpio_to_irq API > > Linus can pass the IRQ via board file? > > and via DT we can use IRQ directly Absolutely not the topic of this patch series. Maybe the subject of another patch later? Best regards, >> 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 */ >> -- >> 2.1.4 >> >> >> _______________________________________________ >> linux-arm-kernel mailing list >> linux-arm-kernel at lists.infradead.org >> http://lists.infradead.org/mailman/listinfo/linux-arm-kernel > > -- Nicolas Ferre