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 701e9c2859SBaruch Siachconfig GPIO_PL061 711e9c2859SBaruch Siach bool "PrimeCell PL061 GPIO support" 721e9c2859SBaruch Siach depends on ARM_AMBA 731e9c2859SBaruch Siach help 741e9c2859SBaruch Siach Say yes here to support the PrimeCell PL061 GPIO device 751e9c2859SBaruch 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 8227fdd325SYoichi Yuasaconfig GPIO_VR41XX 8327fdd325SYoichi Yuasa tristate "NEC VR4100 series General-purpose I/O Uint support" 8427fdd325SYoichi Yuasa depends on CPU_VR41XX 8527fdd325SYoichi Yuasa help 8627fdd325SYoichi Yuasa Say yes here to support the NEC VR4100 series General-purpose I/O Uint 8727fdd325SYoichi Yuasa 88a9c5fff5SDavid Brownellcomment "I2C GPIO expanders:" 89a9c5fff5SDavid Brownell 90bbcd6d54SEric Miaoconfig GPIO_MAX732X 91bbcd6d54SEric Miao tristate "MAX7319, MAX7320-7327 I2C Port Expanders" 92bbcd6d54SEric Miao depends on I2C 93bbcd6d54SEric Miao help 94bbcd6d54SEric Miao Say yes here to support the MAX7319, MAX7320-7327 series of I2C 95bbcd6d54SEric Miao Port Expanders. Each IO port on these chips has a fixed role of 96bbcd6d54SEric Miao Input (designated by 'I'), Push-Pull Output ('O'), or Open-Drain 97bbcd6d54SEric Miao Input and Output (designed by 'P'). The combinations are listed 98bbcd6d54SEric Miao below: 99bbcd6d54SEric Miao 100bbcd6d54SEric Miao 8 bits: max7319 (8I), max7320 (8O), max7321 (8P), 101bbcd6d54SEric Miao max7322 (4I4O), max7323 (4P4O) 102bbcd6d54SEric Miao 103bbcd6d54SEric Miao 16 bits: max7324 (8I8O), max7325 (8P8O), 104bbcd6d54SEric Miao max7326 (4I12O), max7327 (4P12O) 105bbcd6d54SEric Miao 106bbcd6d54SEric Miao Board setup code must specify the model to use, and the start 107bbcd6d54SEric Miao number for these GPIOs. 108bbcd6d54SEric Miao 109f3dc3630SGuennadi Liakhovetskiconfig GPIO_PCA953X 110ab5dc372SDavid Brownell tristate "PCA953x, PCA955x, TCA64xx, and MAX7310 I/O ports" 1119e60fdcfSeric miao depends on I2C 1129e60fdcfSeric miao help 1137059d4b0SDavid Brownell Say yes here to provide access to several register-oriented 1147059d4b0SDavid Brownell SMBus I/O expanders, made mostly by NXP or TI. Compatible 1157059d4b0SDavid Brownell models include: 1167059d4b0SDavid Brownell 1177059d4b0SDavid Brownell 4 bits: pca9536, pca9537 1187059d4b0SDavid Brownell 119ab5dc372SDavid Brownell 8 bits: max7310, pca9534, pca9538, pca9554, pca9557, 120ab5dc372SDavid Brownell tca6408 1217059d4b0SDavid Brownell 122ab5dc372SDavid Brownell 16 bits: pca9535, pca9539, pca9555, tca6416 1239e60fdcfSeric miao 1249e60fdcfSeric miao This driver can also be built as a module. If so, the module 125f3dc3630SGuennadi Liakhovetski will be called pca953x. 1269e60fdcfSeric miao 12715fae37dSDavid Brownellconfig GPIO_PCF857X 1281673ad52SDavid Brownell tristate "PCF857x, PCA{85,96}7x, and MAX732[89] I2C GPIO expanders" 12915fae37dSDavid Brownell depends on I2C 13015fae37dSDavid Brownell help 13115fae37dSDavid Brownell Say yes here to provide access to most "quasi-bidirectional" I2C 13215fae37dSDavid Brownell GPIO expanders used for additional digital outputs or inputs. 13315fae37dSDavid Brownell Most of these parts are from NXP, though TI is a second source for 13415fae37dSDavid Brownell some of them. Compatible models include: 13515fae37dSDavid Brownell 13615fae37dSDavid Brownell 8 bits: pcf8574, pcf8574a, pca8574, pca8574a, 1371673ad52SDavid Brownell pca9670, pca9672, pca9674, pca9674a, 1381673ad52SDavid Brownell max7328, max7329 13915fae37dSDavid Brownell 14015fae37dSDavid Brownell 16 bits: pcf8575, pcf8575c, pca8575, 14115fae37dSDavid Brownell pca9671, pca9673, pca9675 14215fae37dSDavid Brownell 14315fae37dSDavid Brownell Your board setup code will need to declare the expanders in 14415fae37dSDavid Brownell use, and assign numbers to the GPIOs they expose. Those GPIOs 14515fae37dSDavid Brownell can then be used from drivers and other kernel code, just like 14615fae37dSDavid Brownell other GPIOs, but only accessible from task contexts. 14715fae37dSDavid Brownell 14815fae37dSDavid Brownell This driver provides an in-kernel interface to those GPIOs using 14915fae37dSDavid Brownell platform-neutral GPIO calls. 15015fae37dSDavid Brownell 151e9d35947SDavid Brownellconfig GPIO_TWL4030 152e9d35947SDavid Brownell tristate "TWL4030, TWL5030, and TPS659x0 GPIOs" 153e9d35947SDavid Brownell depends on TWL4030_CORE 154e9d35947SDavid Brownell help 155e9d35947SDavid Brownell Say yes here to access the GPIO signals of various multi-function 156e9d35947SDavid Brownell power management chips from Texas Instruments. 157e9d35947SDavid Brownell 158*e4b736f1SMark Brownconfig GPIO_WM831X 159*e4b736f1SMark Brown tristate "WM831x GPIOs" 160*e4b736f1SMark Brown depends on MFD_WM831X 161*e4b736f1SMark Brown help 162*e4b736f1SMark Brown Say yes here to access the GPIO signals of WM831x power management 163*e4b736f1SMark Brown chips from Wolfson Microelectronics. 164*e4b736f1SMark Brown 165ff1d5c2fSMichael Bueschcomment "PCI GPIO expanders:" 166ff1d5c2fSMichael Buesch 167ff1d5c2fSMichael Bueschconfig GPIO_BT8XX 168ff1d5c2fSMichael Buesch tristate "BT8XX GPIO abuser" 169ff1d5c2fSMichael Buesch depends on PCI && VIDEO_BT848=n 170ff1d5c2fSMichael Buesch help 171ff1d5c2fSMichael Buesch The BT8xx frame grabber chip has 24 GPIO pins than can be abused 172ff1d5c2fSMichael Buesch as a cheap PCI GPIO card. 173ff1d5c2fSMichael Buesch 174ff1d5c2fSMichael Buesch This chip can be found on Miro, Hauppauge and STB TV-cards. 175ff1d5c2fSMichael Buesch 176ff1d5c2fSMichael Buesch The card needs to be physically altered for using it as a 177ff1d5c2fSMichael Buesch GPIO card. For more information on how to build a GPIO card 178ff1d5c2fSMichael Buesch from a BT8xx TV card, see the documentation file at 179ff1d5c2fSMichael Buesch Documentation/bt8xxgpio.txt 180ff1d5c2fSMichael Buesch 181ff1d5c2fSMichael Buesch If unsure, say N. 182ff1d5c2fSMichael Buesch 183a9c5fff5SDavid Brownellcomment "SPI GPIO expanders:" 184a9c5fff5SDavid Brownell 1850c36ec31SJuergen Beisertconfig GPIO_MAX7301 1860c36ec31SJuergen Beisert tristate "Maxim MAX7301 GPIO expander" 1870c36ec31SJuergen Beisert depends on SPI_MASTER 1880c36ec31SJuergen Beisert help 1890c36ec31SJuergen Beisert gpio driver for Maxim MAX7301 SPI GPIO expander. 1900c36ec31SJuergen Beisert 191e58b9e27SDavid Brownellconfig GPIO_MCP23S08 192e58b9e27SDavid Brownell tristate "Microchip MCP23S08 I/O expander" 193e58b9e27SDavid Brownell depends on SPI_MASTER 194e58b9e27SDavid Brownell help 195e58b9e27SDavid Brownell SPI driver for Microchip MCP23S08 I/O expander. This provides 196e58b9e27SDavid Brownell a GPIO interface supporting inputs and outputs. 197e58b9e27SDavid Brownell 1987444a72eSMichael Bueschendif 199