diff options
| author | Stefan Wahren <stefan.wahren@i2se.com> | 2019-08-14 14:00:35 +0300 |
|---|---|---|
| committer | Linus Walleij <linus.walleij@linaro.org> | 2019-08-23 12:09:41 +0300 |
| commit | 472a61e777fe78cdcb6cb6f25efee0ae9f629aca (patch) | |
| tree | f3ee044b2383fa012881daf257e6b4ca90ceefd4 /drivers/pinctrl/pinmux.c | |
| parent | 2dc889a8846d16574794669bbdca7401900695b7 (diff) | |
| download | linux-472a61e777fe78cdcb6cb6f25efee0ae9f629aca.tar.xz | |
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/pinmux.c')
| -rw-r--r-- | drivers/pinctrl/pinmux.c | 24 |
1 files changed, 24 insertions, 0 deletions
diff --git a/drivers/pinctrl/pinmux.c b/drivers/pinctrl/pinmux.c index 020e54f843f9..e914f6efd39e 100644 --- a/drivers/pinctrl/pinmux.c +++ b/drivers/pinctrl/pinmux.c @@ -71,6 +71,30 @@ int pinmux_validate_map(const struct pinctrl_map *map, int i) } /** + * pinmux_can_be_used_for_gpio() - check if a specific pin + * is either muxed to a different function or used as gpio. + * + * @pin: the pin number in the global pin space + * + * Controllers not defined as strict will always return true, + * menaning that the gpio can be used. + */ +bool pinmux_can_be_used_for_gpio(struct pinctrl_dev *pctldev, unsigned pin) +{ + struct pin_desc *desc = pin_desc_get(pctldev, pin); + const struct pinmux_ops *ops = pctldev->desc->pmxops; + + /* Can't inspect pin, assume it can be used */ + if (!desc) + return true; + + if (ops->strict && desc->mux_usecount) + return false; + + return !(ops->strict && !!desc->gpio_owner); +} + +/** * pin_request() - request a single pin to be muxed in, typically for GPIO * @pin: the pin number in the global pin space * @owner: a representation of the owner of this pin; typically the device |