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authorStefan Wahren <stefan.wahren@i2se.com>2019-08-14 14:00:35 +0300
committerLinus Walleij <linus.walleij@linaro.org>2019-08-23 11:09:41 +0200
commit472a61e777fe78cdcb6cb6f25efee0ae9f629aca (patch)
treef3ee044b2383fa012881daf257e6b4ca90ceefd4 /drivers/pinctrl/core.c
parent2dc889a8846d16574794669bbdca7401900695b7 (diff)
pinctrl/gpio: Take MUX usage into account
The user space like gpioinfo only see the GPIO usage but not the MUX usage (e.g. I2C or SPI usage) of a pin. As a user we want to know which pin is free/safe to use. So take the MUX usage of strict pinmux controllers into account to get a more realistic view for ioctl GPIO_GET_LINEINFO_IOCTL. Signed-off-by: Stefan Wahren <stefan.wahren@i2se.com> Tested-by: Ramon Fried <rfried.dev@gmail.com> Signed-off-by: Ramon Fried <rfried.dev@gmail.com> Link: https://lore.kernel.org/r/20190814110035.13451-1-ramon.fried@linux.intel.com Acked-by: Stefan Wahren <stefan.wahren@i2se.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Diffstat (limited to 'drivers/pinctrl/core.c')
-rw-r--r--drivers/pinctrl/core.c28
1 files changed, 28 insertions, 0 deletions
diff --git a/drivers/pinctrl/core.c b/drivers/pinctrl/core.c
index b70df27874d1..2bbd8ee93507 100644
--- a/drivers/pinctrl/core.c
+++ b/drivers/pinctrl/core.c
@@ -736,6 +736,34 @@ int pinctrl_get_group_selector(struct pinctrl_dev *pctldev,
return -EINVAL;
}
+bool pinctrl_gpio_can_use_line(unsigned gpio)
+{
+ struct pinctrl_dev *pctldev;
+ struct pinctrl_gpio_range *range;
+ bool result;
+ int pin;
+
+ /*
+ * Try to obtain GPIO range, if it fails
+ * we're probably dealing with GPIO driver
+ * without a backing pin controller - bail out.
+ */
+ if (pinctrl_get_device_gpio_range(gpio, &pctldev, &range))
+ return true;
+
+ mutex_lock(&pctldev->mutex);
+
+ /* Convert to the pin controllers number space */
+ pin = gpio_to_pin(range, gpio);
+
+ result = pinmux_can_be_used_for_gpio(pctldev, pin);
+
+ mutex_unlock(&pctldev->mutex);
+
+ return result;
+}
+EXPORT_SYMBOL_GPL(pinctrl_gpio_can_use_line);
+
/**
* pinctrl_gpio_request() - request a single pin to be used as GPIO
* @gpio: the GPIO pin number from the GPIO subsystem number space