# # GPIO infrastructure and expanders # config ARCH_WANT_OPTIONAL_GPIOLIB bool help Select this config option from the architecture Kconfig, if it is possible to use gpiolib on the architecture, but let the user decide whether to actually build it or not. Select this instead of ARCH_REQUIRE_GPIOLIB, if your architecture does not depend on GPIOs being available, but rather let the user decide whether he needs it or not. config ARCH_REQUIRE_GPIOLIB bool select GPIOLIB help Platforms select gpiolib if they use this infrastructure for all their GPIOs, usually starting with ones integrated into SOC processors. Selecting this from the architecture code will cause the gpiolib code to always get built in. menuconfig GPIOLIB bool "GPIO Support" depends on ARCH_WANT_OPTIONAL_GPIOLIB || ARCH_REQUIRE_GPIOLIB select GENERIC_GPIO help This enables GPIO support through the generic GPIO library. You only need to enable this, if you also want to enable one or more of the GPIO expansion card drivers below. If unsure, say N. if GPIOLIB config DEBUG_GPIO bool "Debug GPIO calls" depends on DEBUG_KERNEL help Say Y here to add some extra checks and diagnostics to GPIO calls. These checks help ensure that GPIOs have been properly initialized before they are used, and that sleeping calls are not made from non-sleeping contexts. They can make bitbanged serial protocols slower. The diagnostics help catch the type of setup errors that are most common when setting up new platforms or boards. config GPIO_SYSFS bool "/sys/class/gpio/... (sysfs interface)" depends on SYSFS && EXPERIMENTAL help Say Y here to add a sysfs interface for GPIOs. This is mostly useful to work around omissions in a system's kernel support. Those are common in custom and semicustom hardware assembled using standard kernels with a minimum of custom patches. In those cases, userspace code may import a given GPIO from the kernel, if no kernel driver requested it. Kernel drivers may also request that a particular GPIO be exported to userspace; this can be useful when debugging. # put expanders in the right section, in alphabetical order comment "Memory mapped GPIO expanders:" config GPIO_PL061 bool "PrimeCell PL061 GPIO support" depends on ARM_AMBA help Say yes here to support the PrimeCell PL061 GPIO device config GPIO_XILINX bool "Xilinx GPIO support" depends on PPC_OF || MICROBLAZE help Say yes here to support the Xilinx FPGA GPIO device config GPIO_VR41XX tristate "NEC VR4100 series General-purpose I/O Uint support" depends on CPU_VR41XX help Say yes here to support the NEC VR4100 series General-purpose I/O Uint comment "I2C GPIO expanders:" config GPIO_MAX732X tristate "MAX7319, MAX7320-7327 I2C Port Expanders" depends on I2C help Say yes here to support the MAX7319, MAX7320-7327 series of I2C Port Expanders. Each IO port on these chips has a fixed role of Input (designated by 'I'), Push-Pull Output ('O'), or Open-Drain Input and Output (designed by 'P'). The combinations are listed below: 8 bits: max7319 (8I), max7320 (8O), max7321 (8P), max7322 (4I4O), max7323 (4P4O) 16 bits: max7324 (8I8O), max7325 (8P8O), max7326 (4I12O), max7327 (4P12O) Board setup code must specify the model to use, and the start number for these GPIOs. config GPIO_PCA953X tristate "PCA953x, PCA955x, TCA64xx, and MAX7310 I/O ports" depends on I2C help Say yes here to provide access to several register-oriented SMBus I/O expanders, made mostly by NXP or TI. Compatible models include: 4 bits: pca9536, pca9537 8 bits: max7310, pca9534, pca9538, pca9554, pca9557, tca6408 16 bits: pca9535, pca9539, pca9555, tca6416 This driver can also be built as a module. If so, the module will be called pca953x. config GPIO_PCF857X tristate "PCF857x, PCA{85,96}7x, and MAX732[89] I2C GPIO expanders" depends on I2C help Say yes here to provide access to most "quasi-bidirectional" I2C GPIO expanders used for additional digital outputs or inputs. Most of these parts are from NXP, though TI is a second source for some of them. Compatible models include: 8 bits: pcf8574, pcf8574a, pca8574, pca8574a, pca9670, pca9672, pca9674, pca9674a, max7328, max7329 16 bits: pcf8575, pcf8575c, pca8575, pca9671, pca9673, pca9675 Your board setup code will need to declare the expanders in use, and assign numbers to the GPIOs they expose. Those GPIOs can then be used from drivers and other kernel code, just like other GPIOs, but only accessible from task contexts. This driver provides an in-kernel interface to those GPIOs using platform-neutral GPIO calls. config GPIO_TWL4030 tristate "TWL4030, TWL5030, and TPS659x0 GPIOs" depends on TWL4030_CORE help Say yes here to access the GPIO signals of various multi-function power management chips from Texas Instruments. config GPIO_WM831X tristate "WM831x GPIOs" depends on MFD_WM831X help Say yes here to access the GPIO signals of WM831x power management chips from Wolfson Microelectronics. config GPIO_ADP5520 tristate "GPIO Support for ADP5520 PMIC" depends on PMIC_ADP5520 help This option enables support for on-chip GPIO found on Analog Devices ADP5520 PMICs. To compile this driver as a module, choose M here: the module will be called adp5520-gpio. comment "PCI GPIO expanders:" config GPIO_BT8XX tristate "BT8XX GPIO abuser" depends on PCI && VIDEO_BT848=n help The BT8xx frame grabber chip has 24 GPIO pins than can be abused as a cheap PCI GPIO card. This chip can be found on Miro, Hauppauge and STB TV-cards. The card needs to be physically altered for using it as a GPIO card. For more information on how to build a GPIO card from a BT8xx TV card, see the documentation file at Documentation/bt8xxgpio.txt If unsure, say N. config GPIO_LANGWELL bool "Intel Moorestown Platform Langwell GPIO support" depends on PCI help Say Y here to support Intel Moorestown platform GPIO. comment "SPI GPIO expanders:" config GPIO_MAX7301 tristate "Maxim MAX7301 GPIO expander" depends on SPI_MASTER help gpio driver for Maxim MAX7301 SPI GPIO expander. config GPIO_MCP23S08 tristate "Microchip MCP23S08 I/O expander" depends on SPI_MASTER help SPI driver for Microchip MCP23S08 I/O expander. This provides a GPIO interface supporting inputs and outputs. config GPIO_MC33880 tristate "Freescale MC33880 high-side/low-side switch" depends on SPI_MASTER help SPI driver for Freescale MC33880 high-side/low-side switch. This provides GPIO interface supporting inputs and outputs. comment "AC97 GPIO expanders:" config GPIO_UCB1400 bool "Philips UCB1400 GPIO" depends on UCB1400_CORE help This enables support for the Philips UCB1400 GPIO pins. The UCB1400 is an AC97 audio codec. To compile this driver as a module, choose M here: the module will be called ucb1400_gpio. endif