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author | 2013-02-17 19:42:50 +0800 | |
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committer | 2013-03-07 05:27:30 +0100 | |
commit | 51e13c2475913d45a3ec546dee647538a9341d6a (patch) | |
tree | 4dc33099bddd1860ac04c6007611329b5789e2b4 /drivers/pinctrl | |
parent | gpio: pl061: support irqdomain (diff) | |
download | linux-51e13c2475913d45a3ec546dee647538a9341d6a.tar.gz linux-51e13c2475913d45a3ec546dee647538a9341d6a.tar.bz2 linux-51e13c2475913d45a3ec546dee647538a9341d6a.zip |
pinctrl: check pinctrl ready for gpio range
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. For example, gpio159 isn't related to back-end pinctrl device
in Hi3620 while other GPIO pins are related to back-end pinctrl device.
Append pinctrl_ready_for_gpio_range() that is used to check whether
pinctrl device with GPIO range is ready. This function will be called
after pinctrl_get_device_gpio_range() fails.
If pinctrl device with GPIO range is found, it means that pinctrl device
is already launched and a certain GPIO pin just don't have back-end pinctrl
interface. Then pinctrl_request_gpio() shouldn't return -EPROBE_DEFER in
this case.
Signed-off-by: Haojian Zhuang <haojian.zhuang@linaro.org>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Diffstat (limited to 'drivers/pinctrl')
-rw-r--r-- | drivers/pinctrl/core.c | 36 |
1 files changed, 36 insertions, 0 deletions
diff --git a/drivers/pinctrl/core.c b/drivers/pinctrl/core.c index e2d214c5c58f..f8a632dc877b 100644 --- a/drivers/pinctrl/core.c +++ b/drivers/pinctrl/core.c @@ -27,6 +27,7 @@ #include <linux/pinctrl/consumer.h> #include <linux/pinctrl/pinctrl.h> #include <linux/pinctrl/machine.h> +#include <asm-generic/gpio.h> #include "core.h" #include "devicetree.h" #include "pinmux.h" @@ -277,6 +278,39 @@ pinctrl_match_gpio_range(struct pinctrl_dev *pctldev, unsigned gpio) } /** + * pinctrl_ready_for_gpio_range() - check if other GPIO pins of + * the same GPIO chip are in 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 + * of the same GPIO chip 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_ready_for_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 @@ -443,6 +477,8 @@ int pinctrl_request_gpio(unsigned gpio) ret = pinctrl_get_device_gpio_range(gpio, &pctldev, &range); if (ret) { + if (pinctrl_ready_for_gpio_range(gpio)) + ret = 0; mutex_unlock(&pinctrl_mutex); return ret; } |