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RIOT/cpu/cc2538/periph/gpio.c
Marian Buschsieweke c2c2cc8592
drivers/periph_gpio: let gpio_read() return bool
Since https://github.com/RIOT-OS/RIOT/pull/20935 gpio_write()
uses a `bool` instead of an `int`. This does the same treatment for
`gpio_read()`.

This does indeed add an instruction to `gpio_read()` implementations.
However, users caring about an instruction more are better served with
`gpio_ll_read()` anyway. And `gpio_read() == 1` is often seen in
newcomer's code, which would now work as expected.
2024-10-23 13:24:09 +02:00

294 lines
6.8 KiB
C

/*
* Copyright (C) 2014 Loci Controls Inc.
* 2016 Freie Universität Berlin
*
* This file is subject to the terms and conditions of the GNU Lesser
* General Public License v2.1. See the file LICENSE in the top level
* directory for more details.
*/
/**
* @ingroup cpu_cc2538
* @ingroup drivers_periph_gpio
* @{
*
* @file
* @brief Low-level GPIO driver implementation
*
* @author Ian Martin <ian@locicontrols.com>
* @author Hauke Petersen <hauke.petersen@fu-berlin.de>
* @author Sebastian Meiling <s@mlng.net>
* @}
*/
#include <assert.h>
#include <stdint.h>
#include "cpu.h"
#include "bitarithm.h"
#include "periph/gpio.h"
#define ENABLE_DEBUG 0
#include "debug.h"
#define MODE_NOTSUP (0xff)
#ifdef MODULE_PERIPH_GPIO_IRQ
static gpio_isr_ctx_t isr_ctx[4][8];
#endif /* MODULE_PERIPH_GPIO_IRQ */
/**
* @brief Access GPIO low-level device
*
* @param[in] pin gpio pin
*
* @return pointer to gpio low level device address
*/
static inline cc2538_gpio_t *gpio(gpio_t pin)
{
return (cc2538_gpio_t *)(pin & GPIO_PORT_MASK);
}
/**
* @brief Helper function to get port number for gpio pin
*
* @param[in] pin gpio pin
*
* @return port number of gpio pin, [0=A - 3=D]
*/
static inline uint8_t _port_num(gpio_t pin)
{
return (uint8_t)((pin & GPIO_PORTNUM_MASK) >> GPIO_PORTNUM_SHIFT) - 1;
}
/**
* @brief Helper function to get pin number for gpio pin
*
* @param[in] pin gpio pin
*
* @return pin number of gpio pin, [0 - 7]
*/
static inline uint8_t _pin_num(gpio_t pin)
{
return (uint8_t)(pin & GPIO_PIN_MASK);
}
/**
* @brief Helper function to get bit mask for gpio pin number
*
* @param[in] pin gpio pin
*
* @return bit mask for gpio pin number, 2^[0 - 7]
*/
static inline uint32_t _pin_mask(gpio_t pin)
{
return (1 << (pin & GPIO_PIN_MASK));
}
/**
* @brief Helper function to get CC2538 gpio number from port and pin
*
* @param[in] pin gpio pin
*
* @return number of gpio pin, [0 - 31]
*/
static inline uint8_t _pp_num(gpio_t pin)
{
return (uint8_t)((_port_num(pin) * GPIO_BITS_PER_PORT) + _pin_num(pin));
}
int gpio_init(gpio_t pin, gpio_mode_t mode)
{
/* check if mode is valid */
if (mode == MODE_NOTSUP) {
return -1;
}
DEBUG("GPIO %"PRIu32", PORT: %u, PIN: %u\n", (uint32_t)pin, _port_num(pin), _pin_num(pin));
/* disable any alternate function and any eventual interrupts */
gpio(pin)->IE &= ~_pin_mask(pin);
gpio(pin)->AFSEL &= ~_pin_mask(pin);
/* configure pull configuration */
IOC->OVER[_pp_num(pin)] = mode;
/* set pin direction */
if (mode == GPIO_OUT) {
gpio(pin)->DIR |= _pin_mask(pin);
}
else {
gpio(pin)->DIR &= ~_pin_mask(pin);
}
return 0;
}
bool gpio_read(gpio_t pin)
{
return (int)(gpio(pin)->DATA & _pin_mask(pin));
}
void gpio_set(gpio_t pin)
{
gpio(pin)->DATA |= _pin_mask(pin);
}
void gpio_clear(gpio_t pin)
{
gpio(pin)->DATA &= ~_pin_mask(pin);
}
void gpio_toggle(gpio_t pin)
{
gpio(pin)->DATA ^= _pin_mask(pin);
}
void gpio_write(gpio_t pin, bool value)
{
if (value) {
gpio(pin)->DATA |= _pin_mask(pin);
}
else {
gpio(pin)->DATA &= ~_pin_mask(pin);
}
}
#ifdef MODULE_PERIPH_GPIO_IRQ
int gpio_init_int(gpio_t pin, gpio_mode_t mode, gpio_flank_t flank,
gpio_cb_t cb, void *arg)
{
if (gpio_init(pin, mode) != 0) {
return -1;
}
/* store the callback information for later: */
isr_ctx[_port_num(pin)][_pin_num(pin)].cb = cb;
isr_ctx[_port_num(pin)][_pin_num(pin)].arg = arg;
/* enable power-up interrupts for this GPIO port: */
SYS_CTRL->IWE |= (1 << _port_num(pin));
/* configure the active flank(s) */
gpio(pin)->IS &= ~_pin_mask(pin);
switch(flank) {
case GPIO_FALLING:
gpio(pin)->IBE &= ~_pin_mask(pin);
gpio(pin)->IEV &= ~_pin_mask(pin);
gpio(pin)->P_EDGE_CTRL |= (1 << _pp_num(pin));
break;
case GPIO_RISING:
gpio(pin)->IBE &= ~_pin_mask(pin);
gpio(pin)->IEV |= _pin_mask(pin);
gpio(pin)->P_EDGE_CTRL &= ~(1 << _pp_num(pin));
break;
case GPIO_BOTH:
gpio(pin)->IBE |= _pin_mask(pin);
break;
default:
return -1;
}
/* reset interrupt status */
gpio(pin)->IC = _pin_mask(pin);
gpio(pin)->PI_IEN |= (1 << _pp_num(pin));
/* enable global interrupt for the selected GPIO port */
NVIC_EnableIRQ(GPIO_PORT_A_IRQn + _port_num(pin));
/* unmask pin interrupt */
gpio(pin)->IE |= _pin_mask(pin);
return 0;
}
void gpio_irq_enable(gpio_t pin)
{
gpio(pin)->IE |= _pin_mask(pin);
}
void gpio_irq_disable(gpio_t pin)
{
gpio(pin)->IE &= ~_pin_mask(pin);
}
static inline void handle_isr(uint8_t port_num)
{
cc2538_gpio_t *port = ((cc2538_gpio_t *)GPIO_BASE) + port_num;
uint32_t state = port->MIS;
port->IC = 0x000000ff;
port->IRQ_DETECT_ACK = (0xff << (port_num * GPIO_BITS_PER_PORT));
/* If only one bit it is set in state (one GPIO pin caused an interrupt),
* don't loop over all 8 bits.
*
* Use clz to get the position of the first interrupt bit and clear it,
* looping only as many times as there are actual interrupts.
*/
/* mask all non-GPIO bits */
state &= (1 << GPIO_BITS_PER_PORT) - 1;
uint8_t pin = 0;
while (state) {
state = bitarithm_test_and_clear(state, &pin);
isr_ctx[port_num][pin].cb(isr_ctx[port_num][pin].arg);
}
cortexm_isr_end();
}
/** @brief Interrupt service routine for Port A */
void isr_gpioa(void)
{
handle_isr(0);
}
/** @brief Interrupt service routine for Port B */
void isr_gpiob(void)
{
handle_isr(1);
}
/** @brief Interrupt service routine for Port C */
void isr_gpioc(void)
{
handle_isr(2);
}
/** @brief Interrupt service routine for Port D */
void isr_gpiod(void)
{
handle_isr(3);
}
#endif /* MODULE_PERIPH_GPIO_IRQ */
/* CC2538 specific add-on GPIO functions */
void gpio_init_af(gpio_t pin, uint8_t sel, uint8_t over)
{
assert(pin != GPIO_UNDEF);
IOC->OVER[_pp_num(pin)] = over;
if (over != GPIO_OUT) {
IOC->PINS[sel] = _pp_num(pin);
}
else {
IOC->SEL[_pp_num(pin)] = sel;
}
/* enable alternative function mode */
gpio(pin)->AFSEL |= _pin_mask(pin);
}
void gpio_init_mux(gpio_t pin, uint8_t over, uint8_t sel, uint8_t func)
{
assert(pin != GPIO_UNDEF);
/* configure pin function and multiplexing */
if (over != GPIO_MUX_NONE) {
IOC->OVER[_pp_num(pin)] = over;
}
if (sel != GPIO_MUX_NONE) {
IOC->SEL[_pp_num(pin)] = sel;
}
if (func != GPIO_MUX_NONE) {
IOC->PINS[func] = _pp_num(pin);
}
/* enable alternative function mode */
gpio(pin)->AFSEL |= _pin_mask(pin);
}