Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
os
linux
pinctrl: apple: Implement GPIO func check callback
This function will check if the indicated function enumerator
i.e. the value set into bits 5 and 6 of the pin configuration
register, is zero and thus corresponds to the GPIO mode of the
pin.
This may be necessary to know since the pin controller is
flagged as "strict": once you set a pin *explicitly* to GPIO
mode using function 0, the core is unaware that this is
actually the GPIO mode, and clients may be denied to
retrieve the pin as a GPIO.
Currently none of the in-kernel device trees sets any pin to
GPIO mode, but this may happen any day.
Reviewed-by: Sven Peter <sven@kernel.org>
Reviewed-by: Bartosz Golaszewski <bartosz.golaszewski@oss.qualcomm.com>
Signed-off-by: Linus Walleij <linusw@kernel.org>
+8
+8
drivers/pinctrl/pinctrl-apple-gpio.c
+8
drivers/pinctrl/pinctrl-apple-gpio.c
···
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/* Pin multiplexer functions */
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+
static bool apple_gpio_pinmux_func_is_gpio(struct pinctrl_dev *pctldev,
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+
unsigned int selector)
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{
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/* Function selector 0 is always the GPIO mode */
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return (selector == 0);
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}
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+
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static int apple_gpio_pinmux_set(struct pinctrl_dev *pctldev, unsigned int func,
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unsigned int group)
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{
···
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.get_functions_count = pinmux_generic_get_function_count,
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.get_function_name = pinmux_generic_get_function_name,
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.get_function_groups = pinmux_generic_get_function_groups,
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.function_is_gpio = apple_gpio_pinmux_func_is_gpio,
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.set_mux = apple_gpio_pinmux_set,
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.strict = true,
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};