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@@ -72,8 +72,8 @@ in this document, but drivers acting as clients to the GPIO interface must
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not care how it's implemented.)
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That said, if the convention is supported on their platform, drivers should
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-use it when possible. Platforms must select ARCH_REQUIRE_GPIOLIB or
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-ARCH_WANT_OPTIONAL_GPIOLIB in their Kconfig. Drivers that can't work without
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+use it when possible. Platforms must select GPIOLIB if GPIO functionality
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+is strictly required. Drivers that can't work without
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standard GPIO calls should have Kconfig entries which depend on GPIOLIB. The
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GPIO calls are available, either as "real code" or as optimized-away stubs,
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when drivers use the include file:
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@@ -553,22 +553,14 @@ either NULL or the label associated with that GPIO when it was requested.
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Platform Support
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----------------
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-To support this framework, a platform's Kconfig will "select" either
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-ARCH_REQUIRE_GPIOLIB or ARCH_WANT_OPTIONAL_GPIOLIB
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-and arrange that its <asm/gpio.h> includes <asm-generic/gpio.h> and defines
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-three functions: gpio_get_value(), gpio_set_value(), and gpio_cansleep().
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+To force-enable this framework, a platform's Kconfig will "select" GPIOLIB,
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+else it is up to the user to configure support for GPIO.
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It may also provide a custom value for ARCH_NR_GPIOS, so that it better
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reflects the number of GPIOs in actual use on that platform, without
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wasting static table space. (It should count both built-in/SoC GPIOs and
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also ones on GPIO expanders.
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-ARCH_REQUIRE_GPIOLIB means that the gpiolib code will always get compiled
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-into the kernel on that architecture.
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-
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-ARCH_WANT_OPTIONAL_GPIOLIB means the gpiolib code defaults to off and the user
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-can enable it and build it into the kernel optionally.
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-
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If neither of these options are selected, the platform does not support
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GPIOs through GPIO-lib and the code cannot be enabled by the user.
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