162306a36Sopenharmony_ci=========================== 262306a36Sopenharmony_ciSamsung GPIO implementation 362306a36Sopenharmony_ci=========================== 462306a36Sopenharmony_ci 562306a36Sopenharmony_ciIntroduction 662306a36Sopenharmony_ci------------ 762306a36Sopenharmony_ci 862306a36Sopenharmony_ciThis outlines the Samsung GPIO implementation and the architecture 962306a36Sopenharmony_cispecific calls provided alongside the drivers/gpio core. 1062306a36Sopenharmony_ci 1162306a36Sopenharmony_ci 1262306a36Sopenharmony_ciGPIOLIB integration 1362306a36Sopenharmony_ci------------------- 1462306a36Sopenharmony_ci 1562306a36Sopenharmony_ciThe gpio implementation uses gpiolib as much as possible, only providing 1662306a36Sopenharmony_cispecific calls for the items that require Samsung specific handling, such 1762306a36Sopenharmony_cias pin special-function or pull resistor control. 1862306a36Sopenharmony_ci 1962306a36Sopenharmony_ciGPIO numbering is synchronised between the Samsung and gpiolib system. 2062306a36Sopenharmony_ci 2162306a36Sopenharmony_ci 2262306a36Sopenharmony_ciPIN configuration 2362306a36Sopenharmony_ci----------------- 2462306a36Sopenharmony_ci 2562306a36Sopenharmony_ciPin configuration is specific to the Samsung architecture, with each SoC 2662306a36Sopenharmony_ciregistering the necessary information for the core gpio configuration 2762306a36Sopenharmony_ciimplementation to configure pins as necessary. 2862306a36Sopenharmony_ci 2962306a36Sopenharmony_ciThe s3c_gpio_cfgpin() and s3c_gpio_setpull() provide the means for a 3062306a36Sopenharmony_cidriver or machine to change gpio configuration. 3162306a36Sopenharmony_ci 3262306a36Sopenharmony_ciSee arch/arm/mach-s3c/gpio-cfg.h for more information on these functions. 33