d192baeaa7
Add some documentation in Documentation/arm/Samsung for the GPIO code and where to look for the necessary functions. Update the S3C24XX case as well. Signed-off-by: Ben Dooks <ben-linux@fluff.org>
43 lines
1.2 KiB
Plaintext
43 lines
1.2 KiB
Plaintext
Samsung GPIO implementation
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===========================
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Introduction
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------------
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This outlines the Samsung GPIO implementation and the architecture
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specfic calls provided alongisde the drivers/gpio core.
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S3C24XX (Legacy)
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----------------
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See Documentation/arm/Samsung-S3C24XX/GPIO.txt for more information
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about these devices. Their implementation is being brought into line
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with the core samsung implementation described in this document.
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GPIOLIB integration
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-------------------
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The gpio implementation uses gpiolib as much as possible, only providing
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specific calls for the items that require Samsung specific handling, such
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as pin special-function or pull resistor control.
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GPIO numbering is synchronised between the Samsung and gpiolib system.
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PIN configuration
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-----------------
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Pin configuration is specific to the Samsung architecutre, with each SoC
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registering the necessary information for the core gpio configuration
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implementation to configure pins as necessary.
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The s3c_gpio_cfgpin() and s3c_gpio_setpull() provide the means for a
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driver or machine to change gpio configuration.
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See arch/arm/plat-samsung/include/plat/gpio-cfg.h for more information
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on these functions.
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