pinctrl: add explicit gpio_disable_free pinmux_op
Some pinctrl drivers (Tegra at least) program a pin to be a GPIO in a
completely different manner than they select which function to mux out of
that pin. In order to support a single "free" pinmux_op, the driver would
need to maintain a per-pin state of requested-for-gpio vs. requested-for-
function. However, that's a lot of work when the core already has explicit
separate paths for gpio request/free and function request/free.
So, add a gpio_disable_free op to struct pinmux_ops, and make pin_free()
call it when appropriate.
When doing this, I noticed that when calling pin_request():
!!gpio == (gpio_range != NULL)
... and so I collapsed those two parameters in both pin_request(), and
when adding writing the new code in pin_free().
Also, for pin_free():
!!free_func == (gpio_range != NULL)
However, I didn't want pin_free() to know about the GPIO function naming
special case, so instead, I reworked pin_free() to always return the pin's
previously requested function, and now pinmux_free_gpio() calls
kfree(function). This is much more balanced with the allocation having
been performed in pinmux_request_gpio().
Signed-off-by: Stephen Warren <swarren@nvidia.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
diff --git a/include/linux/pinctrl/pinmux.h b/include/linux/pinctrl/pinmux.h
index 3c430e7..350e32a 100644
--- a/include/linux/pinctrl/pinmux.h
+++ b/include/linux/pinctrl/pinmux.h
@@ -73,6 +73,9 @@
int (*gpio_request_enable) (struct pinctrl_dev *pctldev,
struct pinctrl_gpio_range *range,
unsigned offset);
+ void (*gpio_disable_free) (struct pinctrl_dev *pctldev,
+ struct pinctrl_gpio_range *range,
+ unsigned offset);
};
/* External interface to pinmux */