Merge branch 'master' of git://git.gag.com/fw/altos

1 files changed, 150 insertions, 0 deletions

diff --git a/src/drivers/ao_quadrature.c b/src/drivers/ao_quadrature.c
new file mode 100644
index 00000000..6a2c1bba
--- /dev/null
+++ b/src/drivers/ao_quadrature.c
@@ -0,0 +1,150 @@
+/*
+ * 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_quadrature.h>
+#include <ao_exti.h>
+#if AO_EVENT
+#include <ao_event.h>
+#define ao_quadrature_queue(q)	ao_event_put_isr(AO_EVENT_QUADRATURE, q, ao_quadrature_count[q])
+#else
+#define ao_quadrature_queue(q)
+#endif
+
+__xdata int32_t ao_quadrature_count[AO_QUADRATURE_COUNT];
+
+static uint8_t	ao_quadrature_state[AO_QUADRATURE_COUNT];
+
+#define BIT(a,b)	((a) | ((b) << 1))
+#define STATE(old_a, old_b, new_a, new_b)	(((BIT(old_a, old_b) << 2) | BIT(new_a, new_b)))
+
+#define port(q)	AO_QUADRATURE_ ## q ## _PORT
+#define bita(q) AO_QUADRATURE_ ## q ## _A
+#define bitb(q) AO_QUADRATURE_ ## q ## _B
+
+#define ao_quadrature_update(q) do {					\
+		ao_quadrature_state[q] = ((ao_quadrature_state[q] & 3) << 2); \
+		ao_quadrature_state[q] |= ao_gpio_get(port(q), bita(q), 0); \
+		ao_quadrature_state[q] |= ao_gpio_get(port(q), bitb(q), 0) << 1; \
+	} while (0)
+	
+
+static void
+ao_quadrature_isr(void)
+{
+	uint8_t	q;
+#if AO_QUADRATURE_COUNT > 0
+	ao_quadrature_update(0);
+#endif
+#if AO_QUADRATURE_COUNT > 1
+	ao_quadrature_update(1);
+#endif
+
+	for (q = 0; q < AO_QUADRATURE_COUNT; q++) {
+		switch (ao_quadrature_state[q]) {
+		case STATE(0, 1, 0, 0):
+			ao_quadrature_count[q]++;
+			break;
+		case STATE(1, 0, 0, 0):
+			ao_quadrature_count[q]--;
+			break;
+		default:
+			continue;
+		}
+		ao_quadrature_queue(q);
+		ao_wakeup(&ao_quadrature_count[q]);
+	}
+}
+
+int32_t
+ao_quadrature_poll(uint8_t q)
+{
+	int32_t	ret;
+	ao_arch_critical(ret = ao_quadrature_count[q];);
+	return ret;
+}
+
+int32_t
+ao_quadrature_wait(uint8_t q)
+{
+	ao_sleep(&ao_quadrature_count[q]);
+	return ao_quadrature_poll(q);
+}
+
+static void
+ao_quadrature_test(void)
+{
+#if 1
+	for (;;) {
+		int32_t	c;
+		flush();
+		c = ao_quadrature_wait(0);
+		printf ("new count %6d\n", c);
+		if (c == 100)
+			break;
+	}
+#endif
+#if 0
+	uint8_t	a, old_a, b, old_b;
+
+	old_a = 2; old_b = 2;
+	for (;;) {
+		a = ao_gpio_get(AO_QUADRATURE_PORT, AO_QUADRATURE_A, AO_QUADRATURE_A_PIN);
+		b = ao_gpio_get(AO_QUADRATURE_PORT, AO_QUADRATURE_B, AO_QUADRATURE_B_PIN);
+		if (a != old_a || b != old_b) {
+			printf ("A %d B %d count %ld\n", a, b, ao_quadrature_count);
+			flush();
+			ao_yield();
+			old_a = a;
+			old_b = b;
+		}
+		if (ao_stdin_ready)
+			break;
+	}
+#endif		
+}
+
+static const struct ao_cmds ao_quadrature_cmds[] = {
+	{ ao_quadrature_test,	"q\0Test quadrature" },
+	{ 0, NULL }
+};
+
+#define init(q) do {							\
+		ao_enable_port(port(q));				\
+									\
+		ao_exti_setup(port(q), bita(q),				\
+			      AO_QUADRATURE_MODE|AO_EXTI_MODE_FALLING|AO_EXTI_MODE_RISING|AO_EXTI_PRIORITY_MED, \
+			      ao_quadrature_isr);			\
+		ao_exti_enable(port(q), bita(q));			\
+									\
+		ao_exti_setup(port(q), bitb(q),				\
+			      AO_QUADRATURE_MODE|AO_EXTI_MODE_FALLING|AO_EXTI_MODE_RISING|AO_EXTI_PRIORITY_MED, \
+			      ao_quadrature_isr);			\
+		ao_exti_enable(port(q), bitb(q));			\
+	} while (0)
+
+void
+ao_quadrature_init(void)
+{
+#if AO_QUADRATURE_COUNT > 0
+	init(0);
+#endif
+#if AO_QUADRATURE_COUNT > 1
+	init(1);
+#endif
+	ao_cmd_register(&ao_quadrature_cmds[0]);
+}