altos/lpc: Add pin interrupt driver

Signed-off-by: Keith Packard <keithp@keithp.com>

diff --git a/src/lpc/ao_exti.h b/src/lpc/ao_exti.h
new file mode 100644 (file)
index 0000000..cbe63ea
--- /dev/null
+++ b/src/lpc/ao_exti.h
@@ -0,0 +1,47 @@
+/*
+ * 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.
+ */
+
+#ifndef _AO_EXTI_H_
+#define _AO_EXTI_H_
+
+#define AO_EXTI_MODE_RISING    1
+#define AO_EXTI_MODE_FALLING   2
+#define AO_EXTI_MODE_PULL_UP   4
+#define AO_EXTI_MODE_PULL_DOWN 8
+#define AO_EXTI_PRIORITY_LOW   16
+#define AO_EXTI_PRIORITY_MED   0
+#define AO_EXTI_PRIORITY_HIGH  32
+
+void
+ao_exti_setup(uint8_t gpio, uint8_t pin, uint8_t mode, void (*callback)());
+
+void
+ao_exti_set_mode(uint8_t gpio, uint8_t pin, uint8_t mode);
+
+void
+ao_exti_set_callback(uint8_t gpio, uint8_t pin, void (*callback)());
+
+void
+ao_exti_enable(uint8_t gpio, uint8_t pin);
+
+void
+ao_exti_disable(uint8_t gpio, uint8_t pin);
+
+void
+ao_exti_init(void);
+
+#endif /* _AO_EXTI_H_ */

diff --git a/src/lpc/ao_exti_lpc.c b/src/lpc/ao_exti_lpc.c
new file mode 100644 (file)
index 0000000..2e42dab
--- /dev/null
+++ b/src/lpc/ao_exti_lpc.c
@@ -0,0 +1,151 @@
+/*
+ * 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_exti.h>
+
+#define LPC_NUM_PINS   56
+#define LPC_NUM_PINT   8
+
+static void    (*ao_exti_callback[LPC_NUM_PINT])(void);
+
+static uint8_t ao_pint_map[LPC_NUM_PINS];
+static uint8_t ao_pint_mode[LPC_NUM_PINS];
+static uint8_t ao_pint_inuse;
+static uint8_t ao_pint_enabled;
+
+static void
+ao_exti_isr(uint8_t pint)
+{
+       uint8_t mask = 1 << pint;
+
+       if (lpc_gpio_pin.ist & mask) {
+               lpc_gpio_pin.ist = mask;
+
+               (*ao_exti_callback) ();
+       }
+}
+
+#define pin_isr(n)     void lpc_pin_int ## n ## _isr(void) { ao_exti_isr(n); }
+pin_isr(0)
+pin_isr(1)
+pin_isr(2)
+pin_isr(3)
+pin_isr(4)
+pin_isr(5)
+pin_isr(6)
+pin_isr(7)
+
+#define pin_id(port,pin)       ((port) * 24 + (pin));
+
+void
+ao_exti_setup (uint8_t port, uint8_t pin, uint8_t mode, void (*callback)(void)) {
+       uint8_t         id = pin_id(port,pin);
+       uint8_t         pint;
+       uint32_t        mask;
+       uint8_t         prio;
+
+       for (pint = 0; pint < LPC_NUM_PINT; pint++)
+               if ((ao_pint_inuse & (1 << pint)) == 0)
+                       break;
+       if (pint == LPC_NUM_PINT)
+               ao_panic(AO_PANIC_EXTI);
+
+       mask = (1 << pint);
+       ao_pint_inuse |= mask;
+       ao_pint_enabled &= ~mask;
+       
+       ao_pint_map[id] = pint;
+       ao_exti_callback[pin] = callback;
+
+       /* configure gpio to interrupt routing */
+       lpc_scb.pintsel[pint] = id;
+
+       ao_enable_input(port, pin, mode);
+
+       /* Set edge triggered */
+       lpc_gpio_pin.isel &= ~mask;
+
+       ao_exti_set_mode(port, pin, mode);
+
+       /* Set interrupt mask and rising/falling mode */
+
+       prio = AO_LPC_NVIC_MED_PRIORITY;
+       if (mode & AO_EXTI_PRIORITY_LOW)
+               prio = AO_LPC_NVIC_LOW_PRIORITY;
+       else if (mode & AO_EXTI_PRIORITY_HIGH)
+               prio = AO_LPC_NVIC_HIGH_PRIORITY;
+
+       /* Set priority and enable */
+       lpc_nvic_set_priority(LPC_ISR_PIN_INT0_POS + pint, prio);
+       lpc_nvic_set_enable(LPC_ISR_PIN_INT0_POS + pint);
+}
+
+void
+ao_exti_set_mode(uint8_t port, uint8_t pin, uint8_t mode) {
+       uint8_t         id = pin_id(port,pin);
+       uint8_t         pint = ao_pint_map[id];
+       uint8_t         mask = 1 << pint;
+
+       ao_pint_mode[pint] = mode;
+
+       if (mode & AO_EXTI_MODE_RISING)
+               lpc_gpio_pin.sienr = mask;
+       else
+               lpc_gpio_pin.cienr = mask;
+               
+       if (mode & AO_EXTI_MODE_FALLING)
+               lpc_gpio_pin.sienf = mask;
+       else
+               lpc_gpio_pin.cienf = mask;
+}
+
+void
+ao_exti_set_callback(uint8_t port, uint8_t pin, void (*callback)()) {
+       uint8_t         id = pin_id(port,pin);
+       uint8_t         pint = ao_pint_map[id];
+
+       ao_exti_callback[pint] = callback;
+}
+
+void
+ao_exti_enable(uint8_t port, uint8_t pin)
+{
+       uint8_t         id = pin_id(port,pin);
+       uint8_t         pint = ao_pint_map[id];
+       uint8_t         mask = 1 << pint;
+
+       ao_pint_enabled |= mask;
+       ao_exti_set_mode(port, pin, ao_pint_mode[pint]);
+}
+
+void
+ao_exti_disable(uint8_t port, uint8_t pin) {
+       uint8_t         id = pin_id(port,pin);
+       uint8_t         pint = ao_pint_map[id];
+       uint8_t         mask = 1 << pint;
+
+       ao_pint_enabled &= ~mask;
+       lpc_gpio_pin.cienr = mask;
+       lpc_gpio_pin.cienf = mask;
+}
+
+void
+ao_exti_init(void)
+{
+       lpc_scb.sysahbclkctrl |= (1 << LPC_SCB_SYSAHBCLKCTRL_PINT);
+}