From mboxrd@z Thu Jan 1 00:00:00 1970 From: Dmitry Torokhov Subject: Re: [PATCH] Input: gpio_keys_polled - defer probing if GPIO probing is deferred Date: Sun, 23 Dec 2012 02:06:25 -0800 Message-ID: <20121223100625.GB17407@core.coreip.homeip.net> References: <1356251523-28359-1-git-send-email-juhosg@openwrt.org> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Return-path: Content-Disposition: inline In-Reply-To: <1356251523-28359-1-git-send-email-juhosg@openwrt.org> Sender: stable-owner@vger.kernel.org To: Gabor Juhos Cc: linux-input@vger.kernel.org, Alexandre Pereira da Silva , stable@vger.kernel.org List-Id: linux-input@vger.kernel.org On Sun, Dec 23, 2012 at 09:32:03AM +0100, Gabor Juhos wrote: > If GPIO probing is deferred, the driver tries to > claim an invalid GPIO line which leads to an error > message like this: > > gpio-keys-polled buttons.2: unable to claim gpio 4294966779, err=-22 > gpio-keys-polled: probe of buttons.2 failed with error -22 > > The patch ensures that 'gpio_keys_polled_get_devtree_pdata' > returns -EPROBE_DEFER if any of the GPIOs to register are > deferred. > > Cc: > Signed-off-by: Gabor Juhos > --- > drivers/input/keyboard/gpio_keys_polled.c | 6 ++++++ > 1 file changed, 6 insertions(+) > > diff --git a/drivers/input/keyboard/gpio_keys_polled.c b/drivers/input/keyboard/gpio_keys_polled.c > index f686fd9..cfb54cc 100644 > --- a/drivers/input/keyboard/gpio_keys_polled.c > +++ b/drivers/input/keyboard/gpio_keys_polled.c > @@ -120,6 +120,12 @@ static struct gpio_keys_platform_data *gpio_keys_polled_get_devtree_pdata(struct > if (nbuttons == 0) > return NULL; > > + for_each_child_of_node(node, pp) { > + error = of_get_gpio(pp, 0); > + if (error == -EPROBE_DEFER) > + goto err_out; > + } > + > pdata = kzalloc(sizeof(*pdata) + nbuttons * (sizeof *button), > GFP_KERNEL); > if (!pdata) { > -- Well spotted, thanks. However I think the patch should look like the one below as we should propagate all errors, not only -EPROBE_DEFER, up the stack. Thanks. -- Dmitry Input: gpio_keys_polled - defer probing if GPIO probing is deferred From: Gabor Juhos If GPIO probing is deferred, the driver tries to claim an invalid GPIO line which leads to an error message like this: gpio-keys-polled buttons.2: unable to claim gpio 4294966779, err=-22 gpio-keys-polled: probe of buttons.2 failed with error -22 The patch ensures that error code returned by of_get_gpio_flags (including -EPROBE_DEFER) is propagated up the stack. Cc: stable@vger.kernel.org Signed-off-by: Gabor Juhos Signed-off-by: Dmitry Torokhov --- drivers/input/keyboard/gpio_keys_polled.c | 13 ++++++++++++- 1 file changed, 12 insertions(+), 1 deletion(-) diff --git a/drivers/input/keyboard/gpio_keys_polled.c b/drivers/input/keyboard/gpio_keys_polled.c index f686fd9..e75ca6b 100644 --- a/drivers/input/keyboard/gpio_keys_polled.c +++ b/drivers/input/keyboard/gpio_keys_polled.c @@ -135,6 +135,7 @@ static struct gpio_keys_platform_data *gpio_keys_polled_get_devtree_pdata(struct i = 0; for_each_child_of_node(node, pp) { + int gpio; enum of_gpio_flags flags; if (!of_find_property(pp, "gpios", NULL)) { @@ -143,9 +144,19 @@ static struct gpio_keys_platform_data *gpio_keys_polled_get_devtree_pdata(struct continue; } + gpio = of_get_gpio_flags(pp, 0, &flags); + if (gpio < 0) { + error = gpio; + if (error != -EPROBE_DEFER) + dev_err(dev, + "Failed to get gpio flags, error: %d\n", + error); + goto err_free_pdata; + } + button = &pdata->buttons[i++]; - button->gpio = of_get_gpio_flags(pp, 0, &flags); + button->gpio = gpio; button->active_low = flags & OF_GPIO_ACTIVE_LOW; if (of_property_read_u32(pp, "linux,code", &button->code)) {