| David Brownell | a9c5fff | 2008-02-04 22:28:17 -0800 | [diff] [blame] | 1 | # |
| 2 | # GPIO infrastructure and expanders |
| 3 | # |
| 4 | |
| 5 | config 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 | |
| 12 | menu "GPIO Support" |
| 13 | depends on HAVE_GPIO_LIB |
| 14 | |
| 15 | config 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 | |
| 28 | comment "I2C GPIO expanders:" |
| 29 | |
| eric miao | 9e60fdc | 2008-02-04 22:28:26 -0800 | [diff] [blame] | 30 | config GPIO_PCA9539 |
| 31 | tristate "PCA9539 16-bit I/O port" |
| 32 | depends on I2C |
| 33 | help |
| 34 | Say yes here to support the PCA9539 16-bit I/O port. These |
| 35 | parts are made by NXP and TI. |
| 36 | |
| 37 | This driver can also be built as a module. If so, the module |
| 38 | will be called pca9539. |
| 39 | |
| David Brownell | 15fae37 | 2008-02-04 22:28:24 -0800 | [diff] [blame] | 40 | config GPIO_PCF857X |
| 41 | tristate "PCF857x, PCA857x, and PCA967x I2C GPIO expanders" |
| 42 | depends on I2C |
| 43 | help |
| 44 | Say yes here to provide access to most "quasi-bidirectional" I2C |
| 45 | GPIO expanders used for additional digital outputs or inputs. |
| 46 | Most of these parts are from NXP, though TI is a second source for |
| 47 | some of them. Compatible models include: |
| 48 | |
| 49 | 8 bits: pcf8574, pcf8574a, pca8574, pca8574a, |
| 50 | pca9670, pca9672, pca9674, pca9674a |
| 51 | |
| 52 | 16 bits: pcf8575, pcf8575c, pca8575, |
| 53 | pca9671, pca9673, pca9675 |
| 54 | |
| 55 | Your board setup code will need to declare the expanders in |
| 56 | use, and assign numbers to the GPIOs they expose. Those GPIOs |
| 57 | can then be used from drivers and other kernel code, just like |
| 58 | other GPIOs, but only accessible from task contexts. |
| 59 | |
| 60 | This driver provides an in-kernel interface to those GPIOs using |
| 61 | platform-neutral GPIO calls. |
| 62 | |
| David Brownell | a9c5fff | 2008-02-04 22:28:17 -0800 | [diff] [blame] | 63 | comment "SPI GPIO expanders:" |
| 64 | |
| David Brownell | e58b9e2 | 2008-02-04 22:28:25 -0800 | [diff] [blame] | 65 | config GPIO_MCP23S08 |
| 66 | tristate "Microchip MCP23S08 I/O expander" |
| 67 | depends on SPI_MASTER |
| 68 | help |
| 69 | SPI driver for Microchip MCP23S08 I/O expander. This provides |
| 70 | a GPIO interface supporting inputs and outputs. |
| 71 | |
| David Brownell | a9c5fff | 2008-02-04 22:28:17 -0800 | [diff] [blame] | 72 | endmenu |