From mboxrd@z Thu Jan 1 00:00:00 1970 From: hdegoede@redhat.com (Hans de Goede) Date: Fri, 17 Jun 2016 10:07:34 +0200 Subject: [PATCH] Revert "gpio: bail out silently on NULL descriptors" In-Reply-To: References: <1466014954-17956-1-git-send-email-hdegoede@redhat.com> Message-ID: <3e000ebd-6178-6591-cd17-d67aa0421d57@redhat.com> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org Hi, On 15-06-16 23:04, Linus Walleij wrote: > On Wed, Jun 15, 2016 at 8:22 PM, Hans de Goede wrote: > >> This reverts commit 54d77198fdfb("gpio: bail out silently on NULL >> descriptors"). >> >> This commit causes the following code to fail: >> >> gpio_desc = devm_gpiod_get_optional(dev, ...); >> gpio_irq = gpiod_to_irq(gpio_desc); >> if (gpio_irq >= 0) { >> ret = devm_request_irq(dev, gpio_irq, ...); >> >> And now ret is an error causing the probe function in question to bail. >> >> The problem here is that gpiod_to_irq now returns 0 for a NULL >> gpio_desc while 0 is a valid irq-nr. Also see: >> commit 4c37ce8608a8("gpio: make gpiod_to_irq() return negative for NO_IRQ") >> which specifically avoids returning 0. >> >> Signed-off-by: Hans de Goede > > The first commit was done to fix another regression so if I revert it I get > back the first regression. Ok. > I guess what we need to do is simply make gpiod_to_irq() a > special case and have it behave the way expected for now? That is fine with me. > Hans: I sent a patch like that if it works for you could you give > me your Tested-by? I've just checked the code and code-wise it looks good. I'll test it on actual hw later today. Regards, Hans