Here's the button driver and event queue logic

[fw/altos] / src / drivers / ao_button.c

diff --git a/src/drivers/ao_button.c b/src/drivers/ao_button.c
new file mode 100644 (file)
index 0000000..a507c90
--- /dev/null
+++ b/src/drivers/ao_button.c
@@ -0,0 +1,94 @@
+/*
+ * Copyright © 2012 Keith Packard <keithp@keithp.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; version 2 of the License.
+ *
+ * This program 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
+ * General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License along
+ * with this program; if not, write to the Free Software Foundation, Inc.,
+ * 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA.
+ */
+
+#include <ao.h>
+#include <ao_button.h>
+#include <ao_exti.h>
+#if AO_EVENT
+#include <ao_event.h>
+#define ao_button_queue(b,v)   ao_event_put_isr(AO_EVENT_BUTTON, b, v)
+#else
+#define ao_button_queue(b,v)
+#endif
+
+static uint8_t         ao_button[AO_BUTTON_COUNT];
+static AO_TICK_TYPE    ao_button_time[AO_BUTTON_COUNT];
+
+#define AO_DEBOUNCE    AO_MS_TO_TICKS(20)
+
+#define port(q)        AO_BUTTON_ ## q ## _PORT
+#define bit(q) AO_BUTTON_ ## q
+#define pin(q) AO_BUTTON_ ## q ## _PIN
+
+static void
+ao_button_do(uint8_t b, uint8_t v)
+{
+       /* Debounce */
+       if ((AO_TICK_SIGNED) (ao_tick_count - ao_button_time[b]) < AO_DEBOUNCE)
+               return;
+
+       /* pins are inverted */
+       v = !v;
+       if (ao_button[b] != v) {
+               ao_button[b] = v;
+               ao_button_time[b] = ao_tick_count;
+               ao_button_queue(b, v);
+               ao_wakeup(&ao_button[b]);
+       }
+}
+
+#define ao_button_update(b)    ao_button_do(b, ao_gpio_get(port(b), bit(b), pin(b)))
+
+static void
+ao_button_isr(void)
+{
+#if AO_BUTTON_COUNT > 0
+       ao_button_update(0);
+#endif
+#if AO_BUTTON_COUNT > 1
+       ao_button_update(1);
+#endif
+#if AO_BUTTON_COUNT > 2
+       ao_button_update(2);
+#endif
+#if AO_BUTTON_COUNT > 3
+       ao_button_update(3);
+#endif
+#if AO_BUTTON_COUNT > 4
+       ao_button_update(4);
+#endif
+}
+
+#define init(b) do {                                                   \
+               ao_enable_port(port(b));                                \
+                                                                       \
+               ao_exti_setup(port(b), bit(b),                          \
+                             AO_BUTTON_MODE|AO_EXTI_MODE_FALLING|AO_EXTI_MODE_RISING|AO_EXTI_PRIORITY_MED, \
+                             ao_button_isr);                   \
+               ao_exti_enable(port(b), bit(b));                        \
+       } while (0)
+
+void
+ao_button_init(void)
+{
+#if AO_BUTTON_COUNT > 0
+       init(0);
+#endif
+#if AO_BUTTON_COUNT > 1
+       init(1);
+#endif
+}