libopencm3/lib/stm32/l1/gpio.c

147 lines
3.5 KiB
C

/*
* This file is part of the libopencm3 project.
*
* Copyright (C) 2011 Fergus Noble <fergusnoble@gmail.com>
* Copyright (C) 2012 Karl Palsson <karlp@tweak.net.au>
*
* This library is free software: you can redistribute it and/or modify
* it under the terms of the GNU Lesser General Public License as published by
* the Free Software Foundation, either version 3 of the License, or
* (at your option) any later version.
*
* This library 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 Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public License
* along with this library. If not, see <http://www.gnu.org/licenses/>.
*
* This is virtually a carbon copy of the F4 code...
* TODO: make this code shared by f2, f4, l1
*/
#include <libopencm3/stm32/l1/gpio.h>
void gpio_mode_setup(u32 gpioport, u8 mode, u8 pull_up_down, u16 gpios)
{
u16 i;
u32 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;
u32 ospeedr;
if (otype == GPIO_OTYPE_OD)
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_OSPEED_MASK(i);
ospeedr |= GPIO_OSPEED(i, speed);
}
GPIO_OSPEEDR(gpioport) = ospeedr;
}
void gpio_set_af(u32 gpioport, u8 alt_func_num, u16 gpios)
{
u16 i;
u32 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) ^= 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. */
/* Tell the compiler the variable is actually used. It will get optimized out anyways. */
reg32 = reg32;
/* If (reg32 & GPIO_LCKK) is true, the lock is now active. */
}