1 files changed, 117 insertions, 0 deletions
diff --git a/src/adccmds.c b/src/adccmds.c
new file mode 100644
index 00000000..2ae7f43c
--- /dev/null
+++ b/src/adccmds.c
@@ -0,0 +1,117 @@
+// Commands for controlling GPIO analog-to-digital input pins
+//
+// Copyright (C) 2016  Kevin O'Connor <kevin@koconnor.net>
+//
+// This file may be distributed under the terms of the GNU GPLv3 license.
+
+#include "basecmd.h" // alloc_oid
+#include "board/gpio.h" // struct gpio_adc
+#include "board/irq.h" // irq_save
+#include "command.h" // DECL_COMMAND
+#include "sched.h" // DECL_TASK
+
+struct analog_in {
+    struct timer timer;
+    uint32_t rest_time, sample_time, next_begin_time;
+    uint16_t value, min_value, max_value;
+    struct gpio_adc pin;
+    uint8_t state, sample_count;
+};
+
+static uint8_t
+analog_in_event(struct timer *timer)
+{
+    struct analog_in *a = container_of(timer, struct analog_in, timer);
+    if (gpio_adc_sample(a->pin)) {
+        a->timer.waketime += gpio_adc_sample_time();
+        return SF_RESCHEDULE;
+    }
+    uint16_t value = gpio_adc_read(a->pin);
+    uint8_t state = a->state;
+    if (state >= a->sample_count) {
+        state = 0;
+    } else {
+        value += a->value;
+    }
+    a->value = value;
+    a->state = state+1;
+    if (a->state < a->sample_count) {
+        a->timer.waketime += a->sample_time;
+        return SF_RESCHEDULE;
+    }
+    if (a->value < a->min_value || a->value > a->max_value)
+        shutdown("adc out of range");
+    a->next_begin_time += a->rest_time;
+    a->timer.waketime = a->next_begin_time;
+    return SF_RESCHEDULE;
+}
+
+void
+command_config_analog_in(uint32_t *args)
+{
+    struct analog_in *a = alloc_oid(
+        args[0], command_config_analog_in, sizeof(*a));
+    a->timer.func = analog_in_event;
+    a->pin = gpio_adc_setup(args[1]);
+    a->state = 1;
+}
+DECL_COMMAND(command_config_analog_in, "config_analog_in oid=%c pin=%u");
+
+void
+command_query_analog_in(uint32_t *args)
+{
+    struct analog_in *a = lookup_oid(args[0], command_config_analog_in);
+    sched_del_timer(&a->timer);
+    gpio_adc_clear_sample(a->pin);
+    a->next_begin_time = args[1];
+    a->timer.waketime = a->next_begin_time;
+    a->sample_time = args[2];
+    a->sample_count = args[3];
+    a->state = a->sample_count + 1;
+    a->rest_time = args[4];
+    a->min_value = args[5];
+    a->max_value = args[6];
+    if (! a->sample_count)
+        return;
+    sched_timer(&a->timer);
+}
+DECL_COMMAND(command_query_analog_in,
+             "query_analog_in oid=%c clock=%u sample_ticks=%u sample_count=%c"
+             " rest_ticks=%u min_value=%hu max_value=%hu");
+
+static void
+analog_in_task(void)
+{
+    static uint16_t next;
+    if (!sched_check_periodic(3, &next))
+        return;
+    uint8_t oid;
+    struct analog_in *a;
+    foreach_oid(oid, a, command_config_analog_in) {
+        if (a->state != a->sample_count)
+            continue;
+        uint8_t flag = irq_save();
+        if (a->state != a->sample_count) {
+            irq_restore(flag);
+            continue;
+        }
+        uint16_t value = a->value;
+        uint32_t next_begin_time = a->next_begin_time;
+        a->state++;
+        irq_restore(flag);
+        sendf("analog_in_state oid=%c next_clock=%u value=%hu"
+              , oid, next_begin_time, value);
+    }
+}
+DECL_TASK(analog_in_task);
+
+static void
+analog_in_shutdown(void)
+{
+    uint8_t i;
+    struct analog_in *a;
+    foreach_oid(i, a, command_config_analog_in) {
+        gpio_adc_clear_sample(a->pin);
+    }
+}
+DECL_SHUTDOWN(analog_in_shutdown);