circuitpython/stmhal/extint.c

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/*
* This file is part of the Micro Python project, http://micropython.org/
*
* The MIT License (MIT)
*
* Copyright (c) 2013, 2014 Damien P. George
*
* Permission is hereby granted, free of charge, to any person obtaining a copy
* of this software and associated documentation files (the "Software"), to deal
* in the Software without restriction, including without limitation the rights
* to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
* copies of the Software, and to permit persons to whom the Software is
* furnished to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice shall be included in
* all copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
* AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
* THE SOFTWARE.
*/
#include <stdio.h>
#include <stddef.h>
#include <string.h>
#include "py/nlr.h"
#include "py/runtime.h"
#include "py/gc.h"
#include "py/pfenv.h"
#include "pin.h"
#include "extint.h"
/// \moduleref pyb
/// \class ExtInt - configure I/O pins to interrupt on external events
///
/// There are a total of 22 interrupt lines. 16 of these can come from GPIO pins
/// and the remaining 6 are from internal sources.
///
/// For lines 0 thru 15, a given line can map to the corresponding line from an
/// arbitrary port. So line 0 can map to Px0 where x is A, B, C, ... and
/// line 1 can map to Px1 where x is A, B, C, ...
///
/// def callback(line):
/// print("line =", line)
///
/// Note: ExtInt will automatically configure the gpio line as an input.
///
/// extint = pyb.ExtInt(pin, pyb.ExtInt.IRQ_FALLING, pyb.Pin.PULL_UP, callback)
///
/// Now every time a falling edge is seen on the X1 pin, the callback will be
/// called. Caution: mechanical pushbuttons have "bounce" and pushing or
/// releasing a switch will often generate multiple edges.
/// See: http://www.eng.utah.edu/~cs5780/debouncing.pdf for a detailed
/// explanation, along with various techniques for debouncing.
///
/// Trying to register 2 callbacks onto the same pin will throw an exception.
///
/// If pin is passed as an integer, then it is assumed to map to one of the
/// internal interrupt sources, and must be in the range 16 thru 22.
///
/// All other pin objects go through the pin mapper to come up with one of the
/// gpio pins.
///
/// extint = pyb.ExtInt(pin, mode, pull, callback)
///
/// Valid modes are pyb.ExtInt.IRQ_RISING, pyb.ExtInt.IRQ_FALLING,
/// pyb.ExtInt.IRQ_RISING_FALLING, pyb.ExtInt.EVT_RISING,
/// pyb.ExtInt.EVT_FALLING, and pyb.ExtInt.EVT_RISING_FALLING.
///
/// Only the IRQ_xxx modes have been tested. The EVT_xxx modes have
/// something to do with sleep mode and the WFE instruction.
///
/// Valid pull values are pyb.Pin.PULL_UP, pyb.Pin.PULL_DOWN, pyb.Pin.PULL_NONE.
///
/// There is also a C API, so that drivers which require EXTI interrupt lines
/// can also use this code. See extint.h for the available functions and
/// usrsw.h for an example of using this.
// TODO Add python method to change callback object.
#define EXTI_OFFSET (EXTI_BASE - PERIPH_BASE)
// Macro used to set/clear the bit corresponding to the line in the IMR/EMR
// register in an atomic fashion by using bitband addressing.
#define EXTI_MODE_BB(mode, line) (*(__IO uint32_t *)(PERIPH_BB_BASE + ((EXTI_OFFSET + (mode)) * 32) + ((line) * 4)))
#define EXTI_Mode_Interrupt offsetof(EXTI_TypeDef, IMR)
#define EXTI_Mode_Event offsetof(EXTI_TypeDef, EMR)
#define EXTI_SWIER_BB(line) (*(__IO uint32_t *)(PERIPH_BB_BASE + ((EXTI_OFFSET + offsetof(EXTI_TypeDef, SWIER)) * 32) + ((line) * 4)))
typedef struct {
mp_obj_base_t base;
mp_int_t line;
} extint_obj_t;
STATIC uint32_t pyb_extint_mode[EXTI_NUM_VECTORS];
#if !defined(ETH)
#define ETH_WKUP_IRQn 62 // The 405 doesn't have ETH, but we want a value to put in our table
#endif
STATIC const uint8_t nvic_irq_channel[EXTI_NUM_VECTORS] = {
EXTI0_IRQn, EXTI1_IRQn, EXTI2_IRQn, EXTI3_IRQn, EXTI4_IRQn,
EXTI9_5_IRQn, EXTI9_5_IRQn, EXTI9_5_IRQn, EXTI9_5_IRQn, EXTI9_5_IRQn,
EXTI15_10_IRQn, EXTI15_10_IRQn, EXTI15_10_IRQn, EXTI15_10_IRQn, EXTI15_10_IRQn,
EXTI15_10_IRQn, PVD_IRQn, RTC_Alarm_IRQn, OTG_FS_WKUP_IRQn, ETH_WKUP_IRQn,
OTG_HS_WKUP_IRQn, TAMP_STAMP_IRQn, RTC_WKUP_IRQn
};
// Set override_callback_obj to true if you want to unconditionally set the
// callback function.
uint extint_register(mp_obj_t pin_obj, uint32_t mode, uint32_t pull, mp_obj_t callback_obj, bool override_callback_obj) {
const pin_obj_t *pin = NULL;
uint v_line;
if (MP_OBJ_IS_INT(pin_obj)) {
// If an integer is passed in, then use it to identify lines 16 thru 22
// We expect lines 0 thru 15 to be passed in as a pin, so that we can
// get both the port number and line number.
v_line = mp_obj_get_int(pin_obj);
if (v_line < 16) {
nlr_raise(mp_obj_new_exception_msg_varg(&mp_type_ValueError, "ExtInt vector %d < 16, use a Pin object", v_line));
}
if (v_line >= EXTI_NUM_VECTORS) {
nlr_raise(mp_obj_new_exception_msg_varg(&mp_type_ValueError, "ExtInt vector %d >= max of %d", v_line, EXTI_NUM_VECTORS));
}
} else {
pin = pin_find(pin_obj);
v_line = pin->pin;
}
if (mode != GPIO_MODE_IT_RISING &&
mode != GPIO_MODE_IT_FALLING &&
mode != GPIO_MODE_IT_RISING_FALLING &&
mode != GPIO_MODE_EVT_RISING &&
mode != GPIO_MODE_EVT_FALLING &&
mode != GPIO_MODE_EVT_RISING_FALLING) {
nlr_raise(mp_obj_new_exception_msg_varg(&mp_type_ValueError, "invalid ExtInt Mode: %d", mode));
}
if (pull != GPIO_NOPULL &&
pull != GPIO_PULLUP &&
pull != GPIO_PULLDOWN) {
nlr_raise(mp_obj_new_exception_msg_varg(&mp_type_ValueError, "invalid ExtInt Pull: %d", pull));
}
mp_obj_t *cb = &MP_STATE_PORT(pyb_extint_callback)[v_line];
if (!override_callback_obj && *cb != mp_const_none && callback_obj != mp_const_none) {
nlr_raise(mp_obj_new_exception_msg_varg(&mp_type_ValueError, "ExtInt vector %d is already in use", v_line));
}
// We need to update callback atomically, so we disable the line
// before we update anything.
extint_disable(v_line);
*cb = callback_obj;
pyb_extint_mode[v_line] = (mode & 0x00010000) ? // GPIO_MODE_IT == 0x00010000
EXTI_Mode_Interrupt : EXTI_Mode_Event;
if (*cb != mp_const_none) {
GPIO_InitTypeDef exti;
exti.Pin = pin->pin_mask;
exti.Mode = mode;
exti.Pull = pull;
exti.Speed = GPIO_SPEED_FAST;
HAL_GPIO_Init(pin->gpio, &exti);
// Calling HAL_GPIO_Init does an implicit extint_enable
/* Enable and set NVIC Interrupt to the lowest priority */
HAL_NVIC_SetPriority(nvic_irq_channel[v_line], 0x0F, 0x0F);
HAL_NVIC_EnableIRQ(nvic_irq_channel[v_line]);
}
return v_line;
}
void extint_enable(uint line) {
if (line >= EXTI_NUM_VECTORS) {
return;
}
// Since manipulating IMR/EMR is a read-modify-write, and we want this to
// be atomic, we use the bit-band area to just affect the bit we're
// interested in.
EXTI_MODE_BB(pyb_extint_mode[line], line) = 1;
}
void extint_disable(uint line) {
if (line >= EXTI_NUM_VECTORS) {
return;
}
// Since manipulating IMR/EMR is a read-modify-write, and we want this to
// be atomic, we use the bit-band area to just affect the bit we're
// interested in.
EXTI_MODE_BB(EXTI_Mode_Interrupt, line) = 0;
EXTI_MODE_BB(EXTI_Mode_Event, line) = 0;
}
void extint_swint(uint line) {
if (line >= EXTI_NUM_VECTORS) {
return;
}
EXTI->SWIER = (1 << line);
}
/// \method line()
/// Return the line number that the pin is mapped to.
STATIC mp_obj_t extint_obj_line(mp_obj_t self_in) {
extint_obj_t *self = self_in;
return MP_OBJ_NEW_SMALL_INT(self->line);
}
2014-04-29 18:00:48 -04:00
STATIC MP_DEFINE_CONST_FUN_OBJ_1(extint_obj_line_obj, extint_obj_line);
/// \method enable()
/// Enable a disabled interrupt.
STATIC mp_obj_t extint_obj_enable(mp_obj_t self_in) {
extint_obj_t *self = self_in;
extint_enable(self->line);
return mp_const_none;
}
STATIC MP_DEFINE_CONST_FUN_OBJ_1(extint_obj_enable_obj, extint_obj_enable);
/// \method disable()
/// Disable the interrupt associated with the ExtInt object.
/// This could be useful for debouncing.
STATIC mp_obj_t extint_obj_disable(mp_obj_t self_in) {
extint_obj_t *self = self_in;
extint_disable(self->line);
return mp_const_none;
}
STATIC MP_DEFINE_CONST_FUN_OBJ_1(extint_obj_disable_obj, extint_obj_disable);
/// \method swint()
/// Trigger the callback from software.
STATIC mp_obj_t extint_obj_swint(mp_obj_t self_in) {
extint_obj_t *self = self_in;
extint_swint(self->line);
return mp_const_none;
}
STATIC MP_DEFINE_CONST_FUN_OBJ_1(extint_obj_swint_obj, extint_obj_swint);
// TODO document as a staticmethod
/// \classmethod regs()
/// Dump the values of the EXTI registers.
STATIC mp_obj_t extint_regs(void) {
printf("EXTI_IMR %08lx\n", EXTI->IMR);
printf("EXTI_EMR %08lx\n", EXTI->EMR);
printf("EXTI_RTSR %08lx\n", EXTI->RTSR);
printf("EXTI_FTSR %08lx\n", EXTI->FTSR);
printf("EXTI_SWIER %08lx\n", EXTI->SWIER);
printf("EXTI_PR %08lx\n", EXTI->PR);
return mp_const_none;
}
STATIC MP_DEFINE_CONST_FUN_OBJ_0(extint_regs_fun_obj, extint_regs);
STATIC MP_DEFINE_CONST_STATICMETHOD_OBJ(extint_regs_obj, (mp_obj_t)&extint_regs_fun_obj);
/// \classmethod \constructor(pin, mode, pull, callback)
/// Create an ExtInt object:
///
/// - `pin` is the pin on which to enable the interrupt (can be a pin object or any valid pin name).
/// - `mode` can be one of:
/// - `ExtInt.IRQ_RISING` - trigger on a rising edge;
/// - `ExtInt.IRQ_FALLING` - trigger on a falling edge;
/// - `ExtInt.IRQ_RISING_FALLING` - trigger on a rising or falling edge.
/// - `pull` can be one of:
/// - `pyb.Pin.PULL_NONE` - no pull up or down resistors;
/// - `pyb.Pin.PULL_UP` - enable the pull-up resistor;
/// - `pyb.Pin.PULL_DOWN` - enable the pull-down resistor.
/// - `callback` is the function to call when the interrupt triggers. The
/// callback function must accept exactly 1 argument, which is the line that
/// triggered the interrupt.
STATIC const mp_arg_t pyb_extint_make_new_args[] = {
{ MP_QSTR_pin, MP_ARG_REQUIRED | MP_ARG_OBJ, {.u_obj = MP_OBJ_NULL} },
{ MP_QSTR_mode, MP_ARG_REQUIRED | MP_ARG_INT, {.u_int = 0} },
{ MP_QSTR_pull, MP_ARG_REQUIRED | MP_ARG_INT, {.u_int = 0} },
{ MP_QSTR_callback, MP_ARG_REQUIRED | MP_ARG_OBJ, {.u_obj = MP_OBJ_NULL} },
};
#define PYB_EXTINT_MAKE_NEW_NUM_ARGS MP_ARRAY_SIZE(pyb_extint_make_new_args)
STATIC mp_obj_t extint_make_new(mp_obj_t type_in, mp_uint_t n_args, mp_uint_t n_kw, const mp_obj_t *args) {
// type_in == extint_obj_type
// parse args
mp_arg_val_t vals[PYB_EXTINT_MAKE_NEW_NUM_ARGS];
mp_arg_parse_all_kw_array(n_args, n_kw, args, PYB_EXTINT_MAKE_NEW_NUM_ARGS, pyb_extint_make_new_args, vals);
extint_obj_t *self = m_new_obj(extint_obj_t);
self->base.type = type_in;
self->line = extint_register(vals[0].u_obj, vals[1].u_int, vals[2].u_int, vals[3].u_obj, false);
return self;
}
STATIC void extint_obj_print(void (*print)(void *env, const char *fmt, ...), void *env, mp_obj_t self_in, mp_print_kind_t kind) {
extint_obj_t *self = self_in;
print(env, "<ExtInt line=%u>", self->line);
}
STATIC const mp_map_elem_t extint_locals_dict_table[] = {
{ MP_OBJ_NEW_QSTR(MP_QSTR_line), (mp_obj_t)&extint_obj_line_obj },
{ MP_OBJ_NEW_QSTR(MP_QSTR_enable), (mp_obj_t)&extint_obj_enable_obj },
{ MP_OBJ_NEW_QSTR(MP_QSTR_disable), (mp_obj_t)&extint_obj_disable_obj },
{ MP_OBJ_NEW_QSTR(MP_QSTR_swint), (mp_obj_t)&extint_obj_swint_obj },
{ MP_OBJ_NEW_QSTR(MP_QSTR_regs), (mp_obj_t)&extint_regs_obj },
// class constants
/// \constant IRQ_RISING - interrupt on a rising edge
/// \constant IRQ_FALLING - interrupt on a falling edge
/// \constant IRQ_RISING_FALLING - interrupt on a rising or falling edge
{ MP_OBJ_NEW_QSTR(MP_QSTR_IRQ_RISING), MP_OBJ_NEW_SMALL_INT(GPIO_MODE_IT_RISING) },
{ MP_OBJ_NEW_QSTR(MP_QSTR_IRQ_FALLING), MP_OBJ_NEW_SMALL_INT(GPIO_MODE_IT_FALLING) },
{ MP_OBJ_NEW_QSTR(MP_QSTR_IRQ_RISING_FALLING), MP_OBJ_NEW_SMALL_INT(GPIO_MODE_IT_RISING_FALLING) },
{ MP_OBJ_NEW_QSTR(MP_QSTR_EVT_RISING), MP_OBJ_NEW_SMALL_INT(GPIO_MODE_EVT_RISING) },
{ MP_OBJ_NEW_QSTR(MP_QSTR_EVT_FALLING), MP_OBJ_NEW_SMALL_INT(GPIO_MODE_EVT_FALLING) },
{ MP_OBJ_NEW_QSTR(MP_QSTR_EVT_RISING_FALLING), MP_OBJ_NEW_SMALL_INT(GPIO_MODE_EVT_RISING_FALLING) },
};
STATIC MP_DEFINE_CONST_DICT(extint_locals_dict, extint_locals_dict_table);
const mp_obj_type_t extint_type = {
{ &mp_type_type },
.name = MP_QSTR_ExtInt,
.print = extint_obj_print,
.make_new = extint_make_new,
.locals_dict = (mp_obj_t)&extint_locals_dict,
};
void extint_init0(void) {
for (int i = 0; i < PYB_EXTI_NUM_VECTORS; i++) {
MP_STATE_PORT(pyb_extint_callback)[i] = mp_const_none;
pyb_extint_mode[i] = EXTI_Mode_Interrupt;
}
}
// Interrupt handler
void Handle_EXTI_Irq(uint32_t line) {
if (__HAL_GPIO_EXTI_GET_FLAG(1 << line)) {
__HAL_GPIO_EXTI_CLEAR_FLAG(1 << line);
if (line < EXTI_NUM_VECTORS) {
mp_obj_t *cb = &MP_STATE_PORT(pyb_extint_callback)[line];
if (*cb != mp_const_none) {
// When executing code within a handler we must lock the GC to prevent
// any memory allocations. We must also catch any exceptions.
gc_lock();
nlr_buf_t nlr;
if (nlr_push(&nlr) == 0) {
mp_call_function_1(*cb, MP_OBJ_NEW_SMALL_INT(line));
nlr_pop();
} else {
// Uncaught exception; disable the callback so it doesn't run again.
*cb = mp_const_none;
extint_disable(line);
printf("Uncaught exception in ExtInt interrupt handler line %lu\n", line);
mp_obj_print_exception(printf_wrapper, NULL, (mp_obj_t)nlr.ret_val);
}
gc_unlock();
}
}
}
}