Merge branch 'master'

[fw/altos] / src / samd21 / ao_exti_samd21.c

diff --git a/src/samd21/ao_exti_samd21.c b/src/samd21/ao_exti_samd21.c
new file mode 100644 (file)
index 0000000..688f643
--- /dev/null
+++ b/src/samd21/ao_exti_samd21.c
@@ -0,0 +1,181 @@
+/*
+ * Copyright © 2022 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; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * 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>
+
+struct ao_samd21_exti {
+       void                    (*callback)(void);
+       uint8_t                 pmux;
+       uint8_t                 pincfg;
+};
+
+static struct ao_samd21_exti ao_samd21_exti[SAMD21_NUM_EIC];
+
+static uint8_t
+pin_id(struct samd21_port *port, uint8_t pin)
+{
+       /* Why, atmel, why? */
+       if (port == &samd21_port_a) {
+               switch (pin) {
+               case 24:
+               case 25:
+               case 27:
+                       return pin - 12;
+               case 28:
+               case 30:
+               case 31:
+                       return pin - 20;
+               default:
+                       break;
+               }
+       }
+
+       /* most pins use exti mapped to their pin number directly (mod 16) */
+       return pin & 0xf;
+}
+
+
+void
+samd21_eic_isr(void)
+{
+       uint32_t        intflag = samd21_eic.intflag;
+       uint8_t         id;
+
+       for (id = 0; id < SAMD21_NUM_EIC; id++) {
+               uint32_t mask = (1 << id);
+
+               if (intflag & mask) {
+                       samd21_eic.intflag = mask;
+                       if (ao_samd21_exti[id].callback)
+                               (*ao_samd21_exti[id].callback)();
+               }
+       }
+}
+
+static void
+_ao_exti_set_sense(uint8_t id, uint8_t mode)
+{
+       uint8_t         sense = mode & (SAMD21_EIC_CONFIG_SENSE_RISE | SAMD21_EIC_CONFIG_SENSE_FALL);
+       uint8_t         n = SAMD21_EIC_CONFIG_N(id);
+       uint32_t        config;
+
+       config = samd21_eic.config[n];
+       config &= ~(SAMD21_EIC_CONFIG_SENSE_MASK << SAMD21_EIC_CONFIG_SENSE(id));
+       config |= (sense << SAMD21_EIC_CONFIG_SENSE(id));
+       samd21_eic.config[n] = config;
+}
+
+void
+ao_exti_setup (struct samd21_port *port, uint8_t pin, uint8_t mode, void (*callback)(void))
+{
+       uint8_t                 id = pin_id(port,pin);
+       struct ao_samd21_exti   *exti = &ao_samd21_exti[id];
+
+       if (exti->callback)
+               ao_panic(AO_PANIC_EXTI);
+
+       if (mode & AO_EXTI_PIN_NOCONFIGURE) {
+               ao_enable_port(port);
+               samd21_port_dir_set(port, pin, SAMD21_PORT_DIR_IN);
+               samd21_port_pincfg_set(port, pin,
+                                      (1 << SAMD21_PORT_PINCFG_INEN),
+                                      (1 << SAMD21_PORT_PINCFG_INEN));
+       } else {
+               ao_enable_input(port, pin, mode);
+       }
+
+       ao_arch_block_interrupts();
+
+       exti->callback = callback;
+
+       /* Set edge triggered */
+       _ao_exti_set_sense(id, mode);
+
+       ao_arch_release_interrupts();
+}
+
+void
+ao_exti_set_mode(struct samd21_port *port, uint8_t pin, uint8_t mode)
+{
+       uint8_t                 id = pin_id(port,pin);
+
+       ao_arch_block_interrupts();
+       _ao_exti_set_sense(id, mode);
+       ao_arch_release_interrupts();
+}
+
+void
+ao_exti_set_callback(struct samd21_port *port, uint8_t pin, void (*callback)(void))
+{
+       uint8_t         id = pin_id(port,pin);
+
+       ao_arch_block_interrupts();
+       ao_samd21_exti[id].callback = callback;
+       ao_arch_release_interrupts();
+}
+
+void
+ao_exti_enable(struct samd21_port *port, uint8_t pin)
+{
+       uint8_t         id = pin_id(port,pin);
+
+       ao_arch_block_interrupts();
+       /* configure gpio to interrupt routing */
+       if ((samd21_eic.intenset & (1 << id)) == 0) {
+               ao_samd21_exti[id].pmux = samd21_port_pmux_get(port, pin);
+               ao_samd21_exti[id].pincfg = samd21_port_pincfg_get(port, pin);
+       }
+       samd21_port_pmux_set(port, pin, SAMD21_PORT_PMUX_FUNC_A);
+       samd21_eic.intenset = 1 << id;
+       ao_arch_release_interrupts();
+}
+
+void
+ao_exti_disable(struct samd21_port *port, uint8_t pin)
+{
+       uint8_t         id = pin_id(port,pin);
+
+       ao_arch_block_interrupts();
+       samd21_eic.intenclr = 1 << id;
+       /* restore gpio config */
+       if (ao_samd21_exti[id].pincfg & (1 << SAMD21_PORT_PINCFG_PMUXEN))
+               samd21_port_pmux_set(port, pin, ao_samd21_exti[id].pmux);
+       else
+               samd21_port_pmux_clr(port, pin);
+       ao_arch_release_interrupts();
+}
+
+void
+ao_exti_init(void)
+{
+       samd21_gclk_clkctrl(0, SAMD21_GCLK_CLKCTRL_ID_EIC);
+
+       /* Reset */
+       samd21_eic.ctrl = (1 << SAMD21_EIC_CTRL_SWRST);
+
+       while (samd21_eic.status & (1 << SAMD21_EIC_STATUS_SYNCBUSY))
+               ;
+
+       /* Wire up interrupts */
+       samd21_nvic_set_enable(SAMD21_NVIC_ISR_EIC_POS);
+       samd21_nvic_set_priority(SAMD21_NVIC_ISR_EIC_POS, 3);
+
+       /* Enable */
+       samd21_eic.ctrl = (1 << SAMD21_EIC_CTRL_ENABLE);
+}