1# 2# GPIO infrastructure and expanders 3# 4 5config HAVE_GPIO_LIB 6 bool 7 help 8 Platforms select gpiolib if they use this infrastructure 9 for all their GPIOs, usually starting with ones integrated 10 into SOC processors. 11 12menu "GPIO Support" 13 depends on HAVE_GPIO_LIB 14 15config DEBUG_GPIO 16 bool "Debug GPIO calls" 17 depends on DEBUG_KERNEL 18 help 19 Say Y here to add some extra checks and diagnostics to GPIO calls. 20 The checks help ensure that GPIOs have been properly initialized 21 before they are used and that sleeping calls aren not made from 22 nonsleeping contexts. They can make bitbanged serial protocols 23 slower. The diagnostics help catch the type of setup errors 24 that are most common when setting up new platforms or boards. 25 26# put expanders in the right section, in alphabetical order 27 28comment "I2C GPIO expanders:" 29 30config GPIO_PCA953X 31 tristate "PCA953x, PCA955x, and MAX7310 I/O ports" 32 depends on I2C 33 help 34 Say yes here to provide access to several register-oriented 35 SMBus I/O expanders, made mostly by NXP or TI. Compatible 36 models include: 37 38 4 bits: pca9536, pca9537 39 40 8 bits: max7310, pca9534, pca9538, pca9554, pca9557 41 42 16 bits: pca9535, pca9539, pca9555 43 44 This driver can also be built as a module. If so, the module 45 will be called pca953x. 46 47config GPIO_PCF857X 48 tristate "PCF857x, PCA857x, and PCA967x I2C GPIO expanders" 49 depends on I2C 50 help 51 Say yes here to provide access to most "quasi-bidirectional" I2C 52 GPIO expanders used for additional digital outputs or inputs. 53 Most of these parts are from NXP, though TI is a second source for 54 some of them. Compatible models include: 55 56 8 bits: pcf8574, pcf8574a, pca8574, pca8574a, 57 pca9670, pca9672, pca9674, pca9674a 58 59 16 bits: pcf8575, pcf8575c, pca8575, 60 pca9671, pca9673, pca9675 61 62 Your board setup code will need to declare the expanders in 63 use, and assign numbers to the GPIOs they expose. Those GPIOs 64 can then be used from drivers and other kernel code, just like 65 other GPIOs, but only accessible from task contexts. 66 67 This driver provides an in-kernel interface to those GPIOs using 68 platform-neutral GPIO calls. 69 70comment "SPI GPIO expanders:" 71 72config GPIO_MCP23S08 73 tristate "Microchip MCP23S08 I/O expander" 74 depends on SPI_MASTER 75 help 76 SPI driver for Microchip MCP23S08 I/O expander. This provides 77 a GPIO interface supporting inputs and outputs. 78 79endmenu 80