100 lines
2.6 KiB
C
100 lines
2.6 KiB
C
// Commands for counting edges on GPIO input pins
|
|
//
|
|
// Copyright (C) 2021 Adrian Keet <arkeet@gmail.com>
|
|
//
|
|
// This file may be distributed under the terms of the GNU GPLv3 license.
|
|
|
|
#include "basecmd.h" // oid_alloc
|
|
#include "board/gpio.h" // struct gpio_in
|
|
#include "board/irq.h" // irq_disable
|
|
#include "board/misc.h" // timer_read_time
|
|
#include "command.h" // DECL_COMMAND
|
|
#include "sched.h" // DECL_TASK
|
|
|
|
struct counter {
|
|
struct timer timer;
|
|
uint32_t poll_ticks;
|
|
uint32_t sample_ticks, next_sample_time;
|
|
uint32_t count, last_count_time;
|
|
uint8_t flags;
|
|
struct gpio_in pin;
|
|
};
|
|
|
|
enum {
|
|
CF_PENDING = 1,
|
|
};
|
|
|
|
static struct task_wake counter_wake;
|
|
|
|
static uint_fast8_t
|
|
counter_event(struct timer *timer)
|
|
{
|
|
struct counter *c = container_of(timer, struct counter, timer);
|
|
|
|
uint32_t time = c->timer.waketime;
|
|
uint8_t last_value = c->count & 1;
|
|
uint8_t value = gpio_in_read(c->pin);
|
|
if (last_value != value) {
|
|
c->count++;
|
|
c->last_count_time = time;
|
|
}
|
|
// useful invariant: c->count & 1 == value
|
|
|
|
if (timer_is_before(c->next_sample_time, time)) {
|
|
c->flags |= CF_PENDING;
|
|
c->next_sample_time = time + c->sample_ticks;
|
|
sched_wake_task(&counter_wake);
|
|
}
|
|
|
|
c->timer.waketime += c->poll_ticks;
|
|
return SF_RESCHEDULE;
|
|
}
|
|
|
|
void
|
|
command_config_counter(uint32_t *args)
|
|
{
|
|
struct counter *c = oid_alloc(
|
|
args[0], command_config_counter, sizeof(*c));
|
|
c->pin = gpio_in_setup(args[1], args[2]);
|
|
c->timer.func = counter_event;
|
|
}
|
|
DECL_COMMAND(command_config_counter,
|
|
"config_counter oid=%c pin=%u pull_up=%c");
|
|
|
|
void
|
|
command_query_counter(uint32_t *args)
|
|
{
|
|
struct counter *c = oid_lookup(args[0], command_config_counter);
|
|
sched_del_timer(&c->timer);
|
|
c->timer.waketime = args[1];
|
|
c->poll_ticks = args[2];
|
|
c->sample_ticks = args[3];
|
|
c->next_sample_time = c->timer.waketime; // sample immediately
|
|
sched_add_timer(&c->timer);
|
|
}
|
|
DECL_COMMAND(command_query_counter,
|
|
"query_counter oid=%c clock=%u poll_ticks=%u sample_ticks=%u");
|
|
|
|
void
|
|
counter_task(void)
|
|
{
|
|
if (!sched_check_wake(&counter_wake))
|
|
return;
|
|
|
|
uint8_t oid;
|
|
struct counter *c;
|
|
foreach_oid(oid, c, command_config_counter) {
|
|
if (!(c->flags & CF_PENDING))
|
|
continue;
|
|
irq_disable();
|
|
uint32_t waketime = c->timer.waketime;
|
|
uint32_t count = c->count;
|
|
uint32_t count_time = c->last_count_time;
|
|
c->flags &= ~CF_PENDING;
|
|
irq_enable();
|
|
sendf("counter_state oid=%c next_clock=%u count=%u count_clock=%u",
|
|
oid, waketime, count, count_time);
|
|
}
|
|
}
|
|
DECL_TASK(counter_task);
|