From 60dcacccb7ae8f80ca224e38abdfca1236d1871e Mon Sep 17 00:00:00 2001 From: Fergus Noble Date: Wed, 14 Sep 2011 23:57:43 -0700 Subject: Some updates to the F2 GPIO header plus implementation of GPIO convenience functions. --- lib/stm32f2/gpio.c | 156 +++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 156 insertions(+) create mode 100644 lib/stm32f2/gpio.c (limited to 'lib/stm32f2') diff --git a/lib/stm32f2/gpio.c b/lib/stm32f2/gpio.c new file mode 100644 index 0000000..f2ea55a --- /dev/null +++ b/lib/stm32f2/gpio.c @@ -0,0 +1,156 @@ +/* + * This file is part of the libopencm3 project. + * + * Copyright (C) 2011 Fergus Noble + * + * 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 3 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, see . + */ + +/* + * Basic GPIO handling API. + * + * Examples: + * gpio_set_mode(GPIOC, GPIO_MODE_OUTPUT_2_MHZ, + * GPIO_CNF_OUTPUT_PUSHPULL, GPIO12); + * gpio_set(GPIOB, GPIO4); + * gpio_clear(GPIOG, GPIO2 | GPIO9); + * gpio_get(GPIOC, GPIO1); + * gpio_toggle(GPIOA, GPIO7 | GPIO8); + * reg16 = gpio_port_read(GPIOD); + * gpio_port_write(GPIOF, 0xc8fe); + * + * TODO: + * - GPIO remapping support + */ + +#include + +void gpio_mode_setup(u32 gpioport, u8 mode, u8 pull_up_down, u16 gpios) +{ + u16 i; + u16 moder, pupd; + + /* + * We want to set the config only for the pins mentioned in gpios, + * but keeping the others, so read out the actual config first. + */ + moder = GPIO_MODER(gpioport); + pupd = GPIO_PUPDR(gpioport); + + for (i = 0; i < 16; i++) { + if (!((1 << i) & gpios)) + continue; + + moder &= ~GPIO_MODE_MASK(i); + moder |= GPIO_MODE(i, mode); + pupd &= ~GPIO_PUPD_MASK(i); + pupd |= GPIO_PUPD(i, pull_up_down); + } + + /* Set mode and pull up/down control registers. */ + GPIO_MODER(gpioport) = moder; + GPIO_PUPDR(gpioport) = pupd; +} + +void gpio_set_output_options(u32 gpioport, u8 otype, u8 speed, u16 gpios) +{ + u16 i; + u16 ospeedr; + + if (otype == 0x1) + GPIO_OTYPER(gpioport) |= gpios; + else + GPIO_OTYPER(gpioport) &= ~gpios; + + ospeedr = GPIO_OSPEEDR(gpioport); + + for (i = 0; i < 16; i++) { + if (!((1 << i) & gpios)) + continue + ospeedr &= ~GPIO_OSPEEDR_MASK(i); + ospeedr |= GPIO_OSPEEDR(i, mode); + } + + GPIO_OSPEEDR(gpioport) = ospeedr; +} + +void gpio_set_af(u32 gpioport, u8 alt_func_num, u16 gpios) +{ + u16 i; + u16 afrl, afrh; + + afrl = GPIO_AFRL(gpioport); + afrh = GPIO_AFRH(gpioport); + + for (i = 0; i < 8; i++) { + if (!((1 << i) & gpios)) + continue + afrl &= GPIO_AFR_MASK(i); + afrl |= GPIO_AFR(i, alt_func_num); + } + + for (i = 8; i < 16; i++) { + if (!((1 << i) & gpios)) + continue + afrl &= GPIO_AFR_MASK(i-8); + afrh |= GPIO_AFR(i-8, alt_func_num); + } + + GPIO_AFRL(gpioport) = afrl; + GPIO_AFRH(gpioport) = afrh; +} + +void gpio_set(u32 gpioport, u16 gpios) +{ + GPIO_BSRR(gpioport) = gpios; +} + +void gpio_clear(u32 gpioport, u16 gpios) +{ + GPIO_BSRR(gpioport) = gpios << 16; +} + +u16 gpio_get(u32 gpioport, u16 gpios) +{ + return gpio_port_read(gpioport) & gpios; +} + +void gpio_toggle(u32 gpioport, u16 gpios) +{ + GPIO_ODR(gpioport) = GPIO_IDR(gpioport) ^ gpios; +} + +u16 gpio_port_read(u32 gpioport) +{ + return (u16)GPIO_IDR(gpioport); +} + +void gpio_port_write(u32 gpioport, u16 data) +{ + GPIO_ODR(gpioport) = data; +} + +void gpio_port_config_lock(u32 gpioport, u16 gpios) +{ + u32 reg32; + + /* Special "Lock Key Writing Sequence", see datasheet. */ + GPIO_LCKR(gpioport) = GPIO_LCKK | gpios; /* Set LCKK. */ + GPIO_LCKR(gpioport) = ~GPIO_LCKK & gpios; /* Clear LCKK. */ + GPIO_LCKR(gpioport) = GPIO_LCKK | gpios; /* Set LCKK. */ + reg32 = GPIO_LCKR(gpioport); /* Read LCKK. */ + reg32 = GPIO_LCKR(gpioport); /* Read LCKK again. */ + + /* If (reg32 & GPIO_LCKK) is true, the lock is now active. */ +} -- cgit v1.2.3