zephyr/drivers/gpio/gpio_litex.c

340 lines
9.2 KiB
C

/*
* Copyright (c) 2019-2021 Antmicro <www.antmicro.com>
* Copyright (c) 2021 Raptor Engineering, LLC <sales@raptorengineering.com>
*
* SPDX-License-Identifier: Apache-2.0
*/
#define DT_DRV_COMPAT litex_gpio
#include <errno.h>
#include <device.h>
#include <drivers/gpio.h>
#include <zephyr/types.h>
#include <sys/util.h>
#include <string.h>
#include <logging/log.h>
#include "gpio_utils.h"
#define SUPPORTED_FLAGS (GPIO_INPUT | GPIO_OUTPUT | \
GPIO_OUTPUT_INIT_LOW | GPIO_OUTPUT_INIT_HIGH | \
GPIO_ACTIVE_LOW | GPIO_ACTIVE_HIGH)
#define GPIO_LOW 0
#define GPIO_HIGH 1
#define LOG_LEVEL CONFIG_GPIO_LOG_LEVEL
LOG_MODULE_REGISTER(gpio_litex);
static const char *LITEX_LOG_REG_SIZE_NGPIOS_MISMATCH =
"Cannot handle all of the gpios with the register of given size\n";
static const char *LITEX_LOG_CANNOT_CHANGE_DIR =
"Cannot change port direction selected in device tree\n";
struct gpio_litex_cfg {
volatile uint32_t *reg_addr;
int reg_size;
volatile uint32_t *ev_pending_addr;
volatile uint32_t *ev_enable_addr;
volatile uint32_t *ev_mode_addr;
volatile uint32_t *ev_edge_addr;
int nr_gpios;
bool port_is_output;
};
struct gpio_litex_data {
struct gpio_driver_data common;
const struct device *dev;
sys_slist_t cb;
};
/* Helper macros for GPIO */
#define DEV_GPIO_CFG(dev) \
((const struct gpio_litex_cfg *)(dev)->config)
/* Helper functions for bit / port access */
static inline void set_bit(const struct gpio_litex_cfg *config,
uint32_t bit, bool val)
{
int regv, new_regv;
regv = litex_read(config->reg_addr, config->reg_size);
new_regv = (regv & ~BIT(bit)) | (val << bit);
litex_write(config->reg_addr, config->reg_size, new_regv);
}
static inline uint32_t get_bit(const struct gpio_litex_cfg *config, uint32_t bit)
{
int regv = litex_read(config->reg_addr, config->reg_size);
return !!(regv & BIT(bit));
}
static inline void set_port(const struct gpio_litex_cfg *config, uint32_t value)
{
litex_write(config->reg_addr, config->reg_size, value);
}
static inline uint32_t get_port(const struct gpio_litex_cfg *config)
{
int regv = litex_read(config->reg_addr, config->reg_size);
return (regv & BIT_MASK(config->nr_gpios));
}
/* Driver functions */
static int gpio_litex_configure(const struct device *dev,
gpio_pin_t pin, gpio_flags_t flags)
{
const struct gpio_litex_cfg *gpio_config = DEV_GPIO_CFG(dev);
if (flags & ~SUPPORTED_FLAGS) {
return -ENOTSUP;
}
if ((flags & GPIO_OUTPUT) && (flags & GPIO_INPUT)) {
/* Pin cannot be configured as input and output */
return -ENOTSUP;
} else if (!(flags & (GPIO_INPUT | GPIO_OUTPUT))) {
/* Pin has to be configured as input or output */
return -ENOTSUP;
}
if (flags & GPIO_OUTPUT) {
if (!gpio_config->port_is_output) {
LOG_ERR("%s", LITEX_LOG_CANNOT_CHANGE_DIR);
return -EINVAL;
}
if (flags & GPIO_OUTPUT_INIT_HIGH) {
set_bit(gpio_config, pin, GPIO_HIGH);
} else if (flags & GPIO_OUTPUT_INIT_LOW) {
set_bit(gpio_config, pin, GPIO_LOW);
}
} else {
if (gpio_config->port_is_output) {
LOG_ERR("%s", LITEX_LOG_CANNOT_CHANGE_DIR);
return -EINVAL;
}
}
return 0;
}
static int gpio_litex_port_get_raw(const struct device *dev,
gpio_port_value_t *value)
{
const struct gpio_litex_cfg *gpio_config = DEV_GPIO_CFG(dev);
*value = get_port(gpio_config);
return 0;
}
static int gpio_litex_port_set_masked_raw(const struct device *dev,
gpio_port_pins_t mask,
gpio_port_value_t value)
{
const struct gpio_litex_cfg *gpio_config = DEV_GPIO_CFG(dev);
uint32_t port_val;
port_val = get_port(gpio_config);
port_val = (port_val & ~mask) | (value & mask);
set_port(gpio_config, port_val);
return 0;
}
static int gpio_litex_port_set_bits_raw(const struct device *dev,
gpio_port_pins_t pins)
{
const struct gpio_litex_cfg *gpio_config = DEV_GPIO_CFG(dev);
uint32_t port_val;
port_val = get_port(gpio_config);
port_val |= pins;
set_port(gpio_config, port_val);
return 0;
}
static int gpio_litex_port_clear_bits_raw(const struct device *dev,
gpio_port_pins_t pins)
{
const struct gpio_litex_cfg *gpio_config = DEV_GPIO_CFG(dev);
uint32_t port_val;
port_val = get_port(gpio_config);
port_val &= ~pins;
set_port(gpio_config, port_val);
return 0;
}
static int gpio_litex_port_toggle_bits(const struct device *dev,
gpio_port_pins_t pins)
{
const struct gpio_litex_cfg *gpio_config = DEV_GPIO_CFG(dev);
uint32_t port_val;
port_val = get_port(gpio_config);
port_val ^= pins;
set_port(gpio_config, port_val);
return 0;
}
static void gpio_litex_irq_handler(const struct device *dev)
{
const struct gpio_litex_cfg *gpio_config = DEV_GPIO_CFG(dev);
struct gpio_litex_data *data = dev->data;
uint8_t int_status =
litex_read(gpio_config->ev_pending_addr, gpio_config->reg_size);
uint8_t ev_enabled =
litex_read(gpio_config->ev_enable_addr, gpio_config->reg_size);
/* clear events */
litex_write(gpio_config->ev_pending_addr, gpio_config->reg_size,
int_status);
gpio_fire_callbacks(&data->cb, dev, int_status & ev_enabled);
}
static int gpio_litex_manage_callback(const struct device *dev,
struct gpio_callback *callback, bool set)
{
struct gpio_litex_data *data = dev->data;
return gpio_manage_callback(&data->cb, callback, set);
}
static int gpio_litex_pin_interrupt_configure(const struct device *dev,
gpio_pin_t pin,
enum gpio_int_mode mode,
enum gpio_int_trig trig)
{
const struct gpio_litex_cfg *gpio_config = DEV_GPIO_CFG(dev);
if (gpio_config->port_is_output == true) {
return -ENOTSUP;
}
if (mode == GPIO_INT_MODE_EDGE) {
uint8_t ev_enabled = litex_read(gpio_config->ev_enable_addr,
gpio_config->reg_size);
uint8_t ev_mode = litex_read(gpio_config->ev_mode_addr,
gpio_config->reg_size);
uint8_t ev_edge = litex_read(gpio_config->ev_edge_addr,
gpio_config->reg_size);
litex_write(gpio_config->ev_enable_addr, gpio_config->reg_size,
ev_enabled | BIT(pin));
if (trig == GPIO_INT_TRIG_HIGH) {
/* Change mode to 'edge' and edge to 'rising' */
litex_write(gpio_config->ev_mode_addr, gpio_config->reg_size,
ev_mode & ~BIT(pin));
litex_write(gpio_config->ev_edge_addr, gpio_config->reg_size,
ev_edge & ~BIT(pin));
} else if (trig == GPIO_INT_TRIG_LOW) {
/* Change mode to 'edge' and edge to 'falling' */
litex_write(gpio_config->ev_mode_addr, gpio_config->reg_size,
ev_mode & ~BIT(pin));
litex_write(gpio_config->ev_edge_addr, gpio_config->reg_size,
ev_edge | BIT(pin));
} else if (trig == GPIO_INT_TRIG_BOTH) {
/* Change mode to 'change' */
litex_write(gpio_config->ev_mode_addr, gpio_config->reg_size,
ev_mode | BIT(pin));
}
return 0;
}
if (mode == GPIO_INT_DISABLE) {
uint8_t ev_enabled = litex_read(gpio_config->ev_enable_addr,
gpio_config->reg_size);
litex_write(gpio_config->ev_enable_addr, gpio_config->reg_size,
ev_enabled & ~BIT(pin));
return 0;
}
return -ENOTSUP;
}
static const struct gpio_driver_api gpio_litex_driver_api = {
.pin_configure = gpio_litex_configure,
.port_get_raw = gpio_litex_port_get_raw,
.port_set_masked_raw = gpio_litex_port_set_masked_raw,
.port_set_bits_raw = gpio_litex_port_set_bits_raw,
.port_clear_bits_raw = gpio_litex_port_clear_bits_raw,
.port_toggle_bits = gpio_litex_port_toggle_bits,
.pin_interrupt_configure = gpio_litex_pin_interrupt_configure,
.manage_callback = gpio_litex_manage_callback,
};
/* Device Instantiation */
#define GPIO_LITEX_IRQ_INIT(n) \
do { \
IRQ_CONNECT(DT_INST_IRQN(n), DT_INST_IRQ(n, priority), \
gpio_litex_irq_handler, \
DEVICE_DT_INST_GET(n), 0); \
\
irq_enable(DT_INST_IRQN(n)); \
} while (0)
#define GPIO_LITEX_INIT(n) \
static int gpio_litex_port_init_##n(const struct device *dev); \
BUILD_ASSERT(DT_INST_REG_SIZE(n) != 0 \
&& DT_INST_REG_SIZE(n) % 4 == 0, \
"Register size must be a multiple of 4"); \
\
static const struct gpio_litex_cfg gpio_litex_cfg_##n = { \
.reg_addr = \
(volatile uint32_t *) DT_INST_REG_ADDR(n), \
.reg_size = DT_INST_REG_SIZE(n) / 4, \
.nr_gpios = DT_INST_PROP(n, ngpios), \
IF_ENABLED(DT_INST_IRQ_HAS_IDX(n, 0), ( \
.ev_mode_addr = \
(volatile uint32_t *) DT_INST_REG_ADDR_BY_NAME(n, irq_mode), \
.ev_edge_addr = \
(volatile uint32_t *) DT_INST_REG_ADDR_BY_NAME(n, irq_edge), \
.ev_pending_addr = \
(volatile uint32_t *) DT_INST_REG_ADDR_BY_NAME(n, irq_pend), \
.ev_enable_addr = \
(volatile uint32_t *) DT_INST_REG_ADDR_BY_NAME(n, irq_en), \
)) \
.port_is_output = DT_INST_PROP(n, port_is_output), \
}; \
static struct gpio_litex_data gpio_litex_data_##n; \
\
DEVICE_DT_INST_DEFINE(n, \
gpio_litex_port_init_##n, \
NULL, \
&gpio_litex_data_##n, \
&gpio_litex_cfg_##n, \
POST_KERNEL, \
CONFIG_GPIO_INIT_PRIORITY, \
&gpio_litex_driver_api \
); \
\
static int gpio_litex_port_init_##n(const struct device *dev) \
{ \
const struct gpio_litex_cfg *gpio_config = DEV_GPIO_CFG(dev); \
\
/* each 4-byte register is able to handle 8 GPIO pins */ \
if (gpio_config->nr_gpios > (gpio_config->reg_size * 8)) { \
LOG_ERR("%s", LITEX_LOG_REG_SIZE_NGPIOS_MISMATCH); \
return -EINVAL; \
} \
\
IF_ENABLED(DT_INST_IRQ_HAS_IDX(n, 0), \
(GPIO_LITEX_IRQ_INIT(n);)) \
return 0; \
}
DT_INST_FOREACH_STATUS_OKAY(GPIO_LITEX_INIT)