From mboxrd@z Thu Jan 1 00:00:00 1970 From: haojian.zhuang@linaro.org (Haojian Zhuang) Date: Sun, 3 Feb 2013 01:25:46 +0800 Subject: [PATCH v8 05/12] pinctrl: verify whether gpio chip overlapps range In-Reply-To: <1359825953-15663-1-git-send-email-haojian.zhuang@linaro.org> References: <1359825953-15663-1-git-send-email-haojian.zhuang@linaro.org> Message-ID: <1359825953-15663-6-git-send-email-haojian.zhuang@linaro.org> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org pinctrl_get_device_gpio_range() only checks whether a certain GPIO pin is in gpio range. But maybe some GPIO pins don't have back-end pinctrl interface, it means that these pins are always configured as GPIO function. Append pinctrl_overlapped_gpio_range() that is used to check whether the pins of GPIO chip are overlapped with pins in the GPIO range. This function will be called after pinctrl_get_device_gpio_range() fails. If overlapped GPIO pins are found, it means that pinctrl device is already launched and a certain GPIO pin don't have back-end pinctrl interface. Then pinctrl_request_gpio() shouldn't return -EPROBE_DEFER in this case. Signed-off-by: Haojian Zhuang --- drivers/pinctrl/core.c | 36 ++++++++++++++++++++++++++++++++++++ 1 file changed, 36 insertions(+) diff --git a/drivers/pinctrl/core.c b/drivers/pinctrl/core.c index 5a2fe9a..f5814cf 100644 --- a/drivers/pinctrl/core.c +++ b/drivers/pinctrl/core.c @@ -27,6 +27,7 @@ #include #include #include +#include #include "core.h" #include "devicetree.h" #include "pinmux.h" @@ -293,6 +294,39 @@ pinctrl_match_gpio_range(struct pinctrl_dev *pctldev, unsigned gpio) } /** + * pinctrl_overlapped_gpio_range() - check if the GPIO chip of a certain GPIO + * pin is overlapped with gpio range. + * @gpio: gpio pin to check taken from the global GPIO pin space + * + * This function is complement of pinctrl_match_gpio_range(). If the return + * value of pinctrl_match_gpio_range() is NULL, this function could be used + * to check whether pinctrl device is ready or not. Maybe some GPIO pins + * don't have back-end pinctrl interface. + * If the return value is true, it means that pinctrl device is ready & the + * certain GPIO pin doesn't have back-end pinctrl device. If the return value + * is false, it means that pinctrl device may not be ready. + */ +static bool pinctrl_overlapped_gpio_range(unsigned gpio) +{ + struct pinctrl_dev *pctldev; + struct pinctrl_gpio_range *range = NULL; + struct gpio_chip *chip = gpio_to_chip(gpio); + + /* Loop over the pin controllers */ + list_for_each_entry(pctldev, &pinctrldev_list, node) { + /* Loop over the ranges */ + list_for_each_entry(range, &pctldev->gpio_ranges, node) { + /* Check if any gpio range overlapped with gpio chip */ + if (range->base + range->npins - 1 < chip->base || + range->base > chip->base + chip->ngpio - 1) + continue; + return true; + } + } + return false; +} + +/** * pinctrl_get_device_gpio_range() - find device for GPIO range * @gpio: the pin to locate the pin controller for * @outdev: the pin control device if found @@ -459,6 +493,8 @@ int pinctrl_request_gpio(unsigned gpio) ret = pinctrl_get_device_gpio_range(gpio, &pctldev, &range); if (ret) { + if (pinctrl_overlapped_gpio_range(gpio)) + ret = 0; mutex_unlock(&pinctrl_mutex); return ret; } -- 1.7.10.4