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author | Wolfgang Denk <wd@denx.de> | 2011-10-21 23:35:12 +0200 |
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committer | Wolfgang Denk <wd@denx.de> | 2011-10-21 23:35:12 +0200 |
commit | 1b81f017b04b5a176f5f9230ec979f0f3c55ba5b (patch) | |
tree | e13192c738bcb50238f6a60ef0448b1e2eec516a /include/asm-generic/gpio.h | |
parent | d639a8ccb0aa3c8c9d4ba0b642951f5534dcbdf1 (diff) | |
parent | 3a8653b3ac11b5ee56ce2b8f795826b8bf01eff2 (diff) | |
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Merge branch 'master' of /home/wd/git/u-boot/master
* 'master' of /home/wd/git/u-boot/master:
cosmetic: Fixup fixup_silent_linux() for checkpatch
Correct dependency rule to fix SPL build
Move timestamp and version files into 'generated' subdir
sandbox: Makefile changes to build sandbox architecture
Add generic gpio.h in asm-generic
Adjust dependency rules to permit per-file flags
sandbox: Use uintptr_t for 32/64-bit compatibility
sandbox: Add basic config file
sandbox: Add serial uart
sandbox: Add main program
sandbox: Add OS dependent layer
sandbox: Force command sections to be 4-byte aligned
sandbox: Disable standalone/API support
sandbox: Disable built-in malloc
sandbox: Add bootm support
sandbox: Add board info for architecture
sandbox: Add sandbox board
sandbox: Add architecture lib files
sandbox: Add cpu files
sandbox: Add compiler defines to support a 64-bit x86_64 platform
sandbox: Add architecture image support
Fix use of int as pointer in image.c
sandbox: Add architecture header files
arm: ca9x4_ct_vxp: enable PXE BOOTP options support
arm: ca9x4_ct_vxp: enable pxe command support
Convert ca9x4_ct_vxp to standard env variables
net: bootp: add PXE/RFC 4578 DHCP options support
Add pxe command
lib: add uuid_str_to_bin for use with bootp and PXE uuid
README: document standard image variables
Replace space and tab checks with isblank
cosmetic: remove unneeded curly braces
Add isblank
common: add run_command2 for running simple or hush commands
common, menu: use abortboot for menu timeout
Add generic, reusable menu code
DM9000:Add a byte swap macro for dm9000 io operation.
kw_gpio: fix error in kw_gpio_direction_input
Blackfin: bfin_spi: fix build error when DEBUG is defined
Blackfin: define CONFIG_SYS_CACHELINE_SIZE
video: Moving mx3fb.c to CONFIG_VIDEO
mx31: make HSP clock for mx3fb driver available
MX5: Make IPU display output and pixel format configurable
VIDEO: MX5: export pix format
VIDEO: MX5: Switch MX5 to CONFIG_VIDEO
video: update the Freescale DIU driver to use linux/fb.h
powerpc: cpm2 boards: update fcc register logic
Diffstat (limited to 'include/asm-generic/gpio.h')
-rw-r--r-- | include/asm-generic/gpio.h | 74 |
1 files changed, 74 insertions, 0 deletions
diff --git a/include/asm-generic/gpio.h b/include/asm-generic/gpio.h new file mode 100644 index 0000000..a1ebb28 --- /dev/null +++ b/include/asm-generic/gpio.h @@ -0,0 +1,74 @@ +/* + * Copyright (c) 2011 The Chromium OS Authors. + * See file CREDITS for list of people who contributed to this + * project. + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License as + * published by the Free Software Foundation; either version 2 of + * the License, or (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, write to the Free Software + * Foundation, Inc., 59 Temple Place, Suite 330, Boston, + * MA 02111-1307 USA + */ + +/* + * Generic GPIO API for U-Boot + * + * GPIOs are numbered from 0 to GPIO_COUNT-1 which value is defined + * by the SOC/architecture. + * + * Each GPIO can be an input or output. If an input then its value can + * be read as 0 or 1. If an output then its value can be set to 0 or 1. + * If you try to write an input then the value is undefined. If you try + * to read an output, barring something very unusual, you will get + * back the value of the output that you previously set. + * + * In some cases the operation may fail, for example if the GPIO number + * is out of range, or the GPIO is not available because its pin is + * being used by another function. In that case, functions may return + * an error value of -1. + */ + +/** + * Make a GPIO an input. + * + * @param gp GPIO number + * @return 0 if ok, -1 on error + */ +int gpio_direction_input(int gp); + +/** + * Make a GPIO an output, and set its value. + * + * @param gp GPIO number + * @param value GPIO value (0 for low or 1 for high) + * @return 0 if ok, -1 on error + */ +int gpio_direction_output(int gp, int value); + +/** + * Get a GPIO's value. This will work whether the GPIO is an input + * or an output. + * + * @param gp GPIO number + * @return 0 if low, 1 if high, -1 on error + */ +int gpio_get_value(int gp); + +/** + * Set an output GPIO's value. The GPIO must already be an output of + * this function may have no effect. + * + * @param gp GPIO number + * @param value GPIO value (0 for low or 1 for high) + * @return 0 if ok, -1 on error + */ +int gpio_set_value(int gp, int value); |