From mboxrd@z Thu Jan 1 00:00:00 1970 From: Masahiro Yamada Subject: [RFC PATCH] gpio: of: fix GPIO drivers with multiple gpio_chip for a single node Date: Mon, 24 Oct 2016 16:43:53 +0900 Message-ID: <1477295033-6008-1-git-send-email-yamada.masahiro@socionext.com> Return-path: Sender: linux-kernel-owner@vger.kernel.org To: linux-gpio@vger.kernel.org Cc: Linus Walleij , Vladimir Zapolskiy , Alexandre Courbot , Masahiro Yamada , linux-kernel@vger.kernel.org List-Id: linux-gpio@vger.kernel.org Sylvain Lemieux reports the LPC32xx GPIO driver is broken since commit 762c2e46c059 ("gpio: of: remove of_gpiochip_and_xlate() and struct gg_data"). Probably, gpio-etraxfs.c and gpio-davinci.c are broken as well. Those drivers register multiple gpio_chip that are associated to a single OF node, and their own .of_xlate() checks if the passed gpio_chip is valid. Now, the problem is of_find_gpiochip_by_node() returns the first gpio_chip found to match the given node. So, .of_xlate() fails, except for the first GPIO bank. Reverting the commit could be a solution, but I do not want to go back to the mess of struct gg_data. Another solution here is to take the match by a node pointer and the success of .of_xlate(). It is a bit clumsy to call .of_xlate twice; for gpio_chip matching and for really getting the gpio_desc index. Perhaps, the long-term goal might be to convert drivers to single chip registration, but this commit will solve the problem until then. Signed-off-by: Masahiro Yamada Reported-by: --- drivers/gpio/gpiolib-of.c | 14 +++++++++----- 1 file changed, 9 insertions(+), 5 deletions(-) diff --git a/drivers/gpio/gpiolib-of.c b/drivers/gpio/gpiolib-of.c index ecad3f0..f996596 100644 --- a/drivers/gpio/gpiolib-of.c +++ b/drivers/gpio/gpiolib-of.c @@ -26,14 +26,18 @@ #include "gpiolib.h" -static int of_gpiochip_match_node(struct gpio_chip *chip, void *data) +static int of_gpiochip_match_node_and_xlate(struct gpio_chip *chip, void *data) { - return chip->gpiodev->dev.of_node == data; + struct of_phandle_args *gpiospec = data; + + return chip->gpiodev->dev.of_node == gpiospec->np && + !chip->of_xlate(chip, gpiospec, NULL); } -static struct gpio_chip *of_find_gpiochip_by_node(struct device_node *np) +static struct gpio_chip *of_find_gpiochip_by_xlate( + struct of_phandle_args *gpiospec) { - return gpiochip_find(np, of_gpiochip_match_node); + return gpiochip_find(gpiospec, of_gpiochip_match_node_and_xlate); } static struct gpio_desc *of_xlate_and_get_gpiod_flags(struct gpio_chip *chip, @@ -79,7 +83,7 @@ struct gpio_desc *of_get_named_gpiod_flags(struct device_node *np, return ERR_PTR(ret); } - chip = of_find_gpiochip_by_node(gpiospec.np); + chip = of_find_gpiochip_by_xlate(&gpiospec); if (!chip) { desc = ERR_PTR(-EPROBE_DEFER); goto out; -- 1.9.1