1a9c5fff5SDavid Brownell# 2a9c5fff5SDavid Brownell# GPIO infrastructure and expanders 3a9c5fff5SDavid Brownell# 4a9c5fff5SDavid Brownell 57444a72eSMichael Bueschconfig ARCH_WANT_OPTIONAL_GPIOLIB 6a9c5fff5SDavid Brownell bool 7a9c5fff5SDavid Brownell help 87444a72eSMichael Buesch Select this config option from the architecture Kconfig, if 97444a72eSMichael Buesch it is possible to use gpiolib on the architecture, but let the 107444a72eSMichael Buesch user decide whether to actually build it or not. 117444a72eSMichael Buesch Select this instead of ARCH_REQUIRE_GPIOLIB, if your architecture does 127444a72eSMichael Buesch not depend on GPIOs being available, but rather let the user 137444a72eSMichael Buesch decide whether he needs it or not. 147444a72eSMichael Buesch 157444a72eSMichael Bueschconfig ARCH_REQUIRE_GPIOLIB 167444a72eSMichael Buesch bool 177444a72eSMichael Buesch select GPIOLIB 187444a72eSMichael Buesch help 19a9c5fff5SDavid Brownell Platforms select gpiolib if they use this infrastructure 20a9c5fff5SDavid Brownell for all their GPIOs, usually starting with ones integrated 21a9c5fff5SDavid Brownell into SOC processors. 227444a72eSMichael Buesch Selecting this from the architecture code will cause the gpiolib 237444a72eSMichael Buesch code to always get built in. 24a9c5fff5SDavid Brownell 257444a72eSMichael Buesch 267444a72eSMichael Buesch 277444a72eSMichael Bueschmenuconfig GPIOLIB 287444a72eSMichael Buesch bool "GPIO Support" 297444a72eSMichael Buesch depends on ARCH_WANT_OPTIONAL_GPIOLIB || ARCH_REQUIRE_GPIOLIB 307444a72eSMichael Buesch select GENERIC_GPIO 317444a72eSMichael Buesch help 327444a72eSMichael Buesch This enables GPIO support through the generic GPIO library. 337444a72eSMichael Buesch You only need to enable this, if you also want to enable 347444a72eSMichael Buesch one or more of the GPIO expansion card drivers below. 357444a72eSMichael Buesch 367444a72eSMichael Buesch If unsure, say N. 377444a72eSMichael Buesch 387444a72eSMichael Bueschif GPIOLIB 39a9c5fff5SDavid Brownell 40a9c5fff5SDavid Brownellconfig DEBUG_GPIO 41a9c5fff5SDavid Brownell bool "Debug GPIO calls" 42a9c5fff5SDavid Brownell depends on DEBUG_KERNEL 43a9c5fff5SDavid Brownell help 44a9c5fff5SDavid Brownell Say Y here to add some extra checks and diagnostics to GPIO calls. 45692105b8SMatt LaPlante These checks help ensure that GPIOs have been properly initialized 46692105b8SMatt LaPlante before they are used, and that sleeping calls are not made from 47692105b8SMatt LaPlante non-sleeping contexts. They can make bitbanged serial protocols 48a9c5fff5SDavid Brownell slower. The diagnostics help catch the type of setup errors 49a9c5fff5SDavid Brownell that are most common when setting up new platforms or boards. 50a9c5fff5SDavid Brownell 51d8f388d8SDavid Brownellconfig GPIO_SYSFS 52d8f388d8SDavid Brownell bool "/sys/class/gpio/... (sysfs interface)" 53d8f388d8SDavid Brownell depends on SYSFS && EXPERIMENTAL 54d8f388d8SDavid Brownell help 55d8f388d8SDavid Brownell Say Y here to add a sysfs interface for GPIOs. 56d8f388d8SDavid Brownell 57d8f388d8SDavid Brownell This is mostly useful to work around omissions in a system's 58d8f388d8SDavid Brownell kernel support. Those are common in custom and semicustom 59d8f388d8SDavid Brownell hardware assembled using standard kernels with a minimum of 60d8f388d8SDavid Brownell custom patches. In those cases, userspace code may import 61d8f388d8SDavid Brownell a given GPIO from the kernel, if no kernel driver requested it. 62d8f388d8SDavid Brownell 63d8f388d8SDavid Brownell Kernel drivers may also request that a particular GPIO be 64d8f388d8SDavid Brownell exported to userspace; this can be useful when debugging. 65d8f388d8SDavid Brownell 66a9c5fff5SDavid Brownell# put expanders in the right section, in alphabetical order 67a9c5fff5SDavid Brownell 680bcb6069SJohn Linncomment "Memory mapped GPIO expanders:" 690bcb6069SJohn Linn 70*1e9c2859SBaruch Siachconfig GPIO_PL061 71*1e9c2859SBaruch Siach bool "PrimeCell PL061 GPIO support" 72*1e9c2859SBaruch Siach depends on ARM_AMBA 73*1e9c2859SBaruch Siach help 74*1e9c2859SBaruch Siach Say yes here to support the PrimeCell PL061 GPIO device 75*1e9c2859SBaruch Siach 760bcb6069SJohn Linnconfig GPIO_XILINX 770bcb6069SJohn Linn bool "Xilinx GPIO support" 786fa612b5SMichal Simek depends on PPC_OF || MICROBLAZE 790bcb6069SJohn Linn help 800bcb6069SJohn Linn Say yes here to support the Xilinx FPGA GPIO device 810bcb6069SJohn Linn 82a9c5fff5SDavid Brownellcomment "I2C GPIO expanders:" 83a9c5fff5SDavid Brownell 84bbcd6d54SEric Miaoconfig GPIO_MAX732X 85bbcd6d54SEric Miao tristate "MAX7319, MAX7320-7327 I2C Port Expanders" 86bbcd6d54SEric Miao depends on I2C 87bbcd6d54SEric Miao help 88bbcd6d54SEric Miao Say yes here to support the MAX7319, MAX7320-7327 series of I2C 89bbcd6d54SEric Miao Port Expanders. Each IO port on these chips has a fixed role of 90bbcd6d54SEric Miao Input (designated by 'I'), Push-Pull Output ('O'), or Open-Drain 91bbcd6d54SEric Miao Input and Output (designed by 'P'). The combinations are listed 92bbcd6d54SEric Miao below: 93bbcd6d54SEric Miao 94bbcd6d54SEric Miao 8 bits: max7319 (8I), max7320 (8O), max7321 (8P), 95bbcd6d54SEric Miao max7322 (4I4O), max7323 (4P4O) 96bbcd6d54SEric Miao 97bbcd6d54SEric Miao 16 bits: max7324 (8I8O), max7325 (8P8O), 98bbcd6d54SEric Miao max7326 (4I12O), max7327 (4P12O) 99bbcd6d54SEric Miao 100bbcd6d54SEric Miao Board setup code must specify the model to use, and the start 101bbcd6d54SEric Miao number for these GPIOs. 102bbcd6d54SEric Miao 103f3dc3630SGuennadi Liakhovetskiconfig GPIO_PCA953X 104ab5dc372SDavid Brownell tristate "PCA953x, PCA955x, TCA64xx, and MAX7310 I/O ports" 1059e60fdcfSeric miao depends on I2C 1069e60fdcfSeric miao help 1077059d4b0SDavid Brownell Say yes here to provide access to several register-oriented 1087059d4b0SDavid Brownell SMBus I/O expanders, made mostly by NXP or TI. Compatible 1097059d4b0SDavid Brownell models include: 1107059d4b0SDavid Brownell 1117059d4b0SDavid Brownell 4 bits: pca9536, pca9537 1127059d4b0SDavid Brownell 113ab5dc372SDavid Brownell 8 bits: max7310, pca9534, pca9538, pca9554, pca9557, 114ab5dc372SDavid Brownell tca6408 1157059d4b0SDavid Brownell 116ab5dc372SDavid Brownell 16 bits: pca9535, pca9539, pca9555, tca6416 1179e60fdcfSeric miao 1189e60fdcfSeric miao This driver can also be built as a module. If so, the module 119f3dc3630SGuennadi Liakhovetski will be called pca953x. 1209e60fdcfSeric miao 12115fae37dSDavid Brownellconfig GPIO_PCF857X 1221673ad52SDavid Brownell tristate "PCF857x, PCA{85,96}7x, and MAX732[89] I2C GPIO expanders" 12315fae37dSDavid Brownell depends on I2C 12415fae37dSDavid Brownell help 12515fae37dSDavid Brownell Say yes here to provide access to most "quasi-bidirectional" I2C 12615fae37dSDavid Brownell GPIO expanders used for additional digital outputs or inputs. 12715fae37dSDavid Brownell Most of these parts are from NXP, though TI is a second source for 12815fae37dSDavid Brownell some of them. Compatible models include: 12915fae37dSDavid Brownell 13015fae37dSDavid Brownell 8 bits: pcf8574, pcf8574a, pca8574, pca8574a, 1311673ad52SDavid Brownell pca9670, pca9672, pca9674, pca9674a, 1321673ad52SDavid Brownell max7328, max7329 13315fae37dSDavid Brownell 13415fae37dSDavid Brownell 16 bits: pcf8575, pcf8575c, pca8575, 13515fae37dSDavid Brownell pca9671, pca9673, pca9675 13615fae37dSDavid Brownell 13715fae37dSDavid Brownell Your board setup code will need to declare the expanders in 13815fae37dSDavid Brownell use, and assign numbers to the GPIOs they expose. Those GPIOs 13915fae37dSDavid Brownell can then be used from drivers and other kernel code, just like 14015fae37dSDavid Brownell other GPIOs, but only accessible from task contexts. 14115fae37dSDavid Brownell 14215fae37dSDavid Brownell This driver provides an in-kernel interface to those GPIOs using 14315fae37dSDavid Brownell platform-neutral GPIO calls. 14415fae37dSDavid Brownell 145e9d35947SDavid Brownellconfig GPIO_TWL4030 146e9d35947SDavid Brownell tristate "TWL4030, TWL5030, and TPS659x0 GPIOs" 147e9d35947SDavid Brownell depends on TWL4030_CORE 148e9d35947SDavid Brownell help 149e9d35947SDavid Brownell Say yes here to access the GPIO signals of various multi-function 150e9d35947SDavid Brownell power management chips from Texas Instruments. 151e9d35947SDavid Brownell 152ff1d5c2fSMichael Bueschcomment "PCI GPIO expanders:" 153ff1d5c2fSMichael Buesch 154ff1d5c2fSMichael Bueschconfig GPIO_BT8XX 155ff1d5c2fSMichael Buesch tristate "BT8XX GPIO abuser" 156ff1d5c2fSMichael Buesch depends on PCI && VIDEO_BT848=n 157ff1d5c2fSMichael Buesch help 158ff1d5c2fSMichael Buesch The BT8xx frame grabber chip has 24 GPIO pins than can be abused 159ff1d5c2fSMichael Buesch as a cheap PCI GPIO card. 160ff1d5c2fSMichael Buesch 161ff1d5c2fSMichael Buesch This chip can be found on Miro, Hauppauge and STB TV-cards. 162ff1d5c2fSMichael Buesch 163ff1d5c2fSMichael Buesch The card needs to be physically altered for using it as a 164ff1d5c2fSMichael Buesch GPIO card. For more information on how to build a GPIO card 165ff1d5c2fSMichael Buesch from a BT8xx TV card, see the documentation file at 166ff1d5c2fSMichael Buesch Documentation/bt8xxgpio.txt 167ff1d5c2fSMichael Buesch 168ff1d5c2fSMichael Buesch If unsure, say N. 169ff1d5c2fSMichael Buesch 170a9c5fff5SDavid Brownellcomment "SPI GPIO expanders:" 171a9c5fff5SDavid Brownell 1720c36ec31SJuergen Beisertconfig GPIO_MAX7301 1730c36ec31SJuergen Beisert tristate "Maxim MAX7301 GPIO expander" 1740c36ec31SJuergen Beisert depends on SPI_MASTER 1750c36ec31SJuergen Beisert help 1760c36ec31SJuergen Beisert gpio driver for Maxim MAX7301 SPI GPIO expander. 1770c36ec31SJuergen Beisert 178e58b9e27SDavid Brownellconfig GPIO_MCP23S08 179e58b9e27SDavid Brownell tristate "Microchip MCP23S08 I/O expander" 180e58b9e27SDavid Brownell depends on SPI_MASTER 181e58b9e27SDavid Brownell help 182e58b9e27SDavid Brownell SPI driver for Microchip MCP23S08 I/O expander. This provides 183e58b9e27SDavid Brownell a GPIO interface supporting inputs and outputs. 184e58b9e27SDavid Brownell 1857444a72eSMichael Bueschendif 186