circuitpython/stmhal/i2c.c
Damien George ff91156d34 stmhal: Improved configurability for I2C and SPI busses.
The HAL handles for the I2C/SPI objects are rather large, so we don't
want to unnecessarily include them.
2014-04-20 19:06:15 +01:00

270 lines
9.0 KiB
C

#include <stdio.h>
#include <string.h>
#include "stm32f4xx_hal.h"
#include "nlr.h"
#include "misc.h"
#include "mpconfig.h"
#include "qstr.h"
#include "obj.h"
#include "runtime.h"
#include "pin.h"
#include "genhdr/pins.h"
#include "i2c.h"
#if MICROPY_HW_ENABLE_I2C1
I2C_HandleTypeDef I2CHandle1 = {.Instance = NULL};
#endif
I2C_HandleTypeDef I2CHandle2 = {.Instance = NULL};
void i2c_init0(void) {
// reset the I2C1 handles
#if MICROPY_HW_ENABLE_I2C1
memset(&I2CHandle1, 0, sizeof(I2C_HandleTypeDef));
I2CHandle1.Instance = I2C1;
#endif
memset(&I2CHandle2, 0, sizeof(I2C_HandleTypeDef));
I2CHandle2.Instance = I2C2;
}
void i2c_init(I2C_HandleTypeDef *i2c) {
// init the GPIO lines
GPIO_InitTypeDef GPIO_InitStructure;
GPIO_InitStructure.Mode = GPIO_MODE_AF_OD;
GPIO_InitStructure.Speed = GPIO_SPEED_FAST;
GPIO_InitStructure.Pull = GPIO_NOPULL; // have external pull-up resistors on both lines
const pin_obj_t *pins[2];
if (0) {
#if MICROPY_HW_ENABLE_I2C1
} else if (i2c == &I2CHandle1) {
// X-skin: X9=PB6=SCL, X10=PB7=SDA
pins[0] = &pin_B6;
pins[1] = &pin_B7;
GPIO_InitStructure.Alternate = GPIO_AF4_I2C1;
// enable the I2C clock
__I2C1_CLK_ENABLE();
#endif
} else if (i2c == &I2CHandle2) {
// Y-skin: Y9=PB10=SCL, Y10=PB11=SDA
pins[0] = &pin_B10;
pins[1] = &pin_B11;
GPIO_InitStructure.Alternate = GPIO_AF4_I2C2;
// enable the I2C clock
__I2C2_CLK_ENABLE();
} else {
// I2C does not exist for this board (shouldn't get here, should be checked by caller)
return;
}
// init the GPIO lines
for (uint i = 0; i < 2; i++) {
GPIO_InitStructure.Pin = pins[i]->pin_mask;
HAL_GPIO_Init(pins[i]->gpio, &GPIO_InitStructure);
}
// init the I2C device
i2c->Init.AddressingMode = I2C_ADDRESSINGMODE_7BIT;
i2c->Init.ClockSpeed = 400000;
i2c->Init.DualAddressMode = I2C_DUALADDRESS_DISABLED;
i2c->Init.DutyCycle = I2C_DUTYCYCLE_16_9;
i2c->Init.GeneralCallMode = I2C_GENERALCALL_DISABLED;
i2c->Init.NoStretchMode = I2C_NOSTRETCH_DISABLED;
i2c->Init.OwnAddress1 = 0xfe; // unused
i2c->Init.OwnAddress2 = 0xfe; // unused
if (HAL_I2C_Init(i2c) != HAL_OK) {
// init error
// TODO should raise an exception, but this function is not necessarily going to be
// called via Python, so may not be properly wrapped in an NLR handler
printf("HardwareError: HAL_I2C_Init failed\n");
return;
}
}
/******************************************************************************/
/* Micro Python bindings */
typedef struct _pyb_i2c_obj_t {
mp_obj_base_t base;
I2C_HandleTypeDef *i2c;
} pyb_i2c_obj_t;
STATIC const pyb_i2c_obj_t pyb_i2c_obj[] = {
#if MICROPY_HW_ENABLE_I2C1
{{&pyb_i2c_type}, &I2CHandle1},
#else
{{&pyb_i2c_type}, NULL},
#endif
{{&pyb_i2c_type}, &I2CHandle2}
};
#define PYB_NUM_I2C (sizeof(pyb_i2c_obj) / sizeof(pyb_i2c_obj[0]))
STATIC mp_obj_t pyb_i2c_make_new(mp_obj_t type_in, uint n_args, uint n_kw, const mp_obj_t *args) {
// check arguments
mp_arg_check_num(n_args, n_kw, 1, 1, false);
// get i2c number
machine_int_t i2c_id = mp_obj_get_int(args[0]) - 1;
// check i2c number
if (!(0 <= i2c_id && i2c_id < PYB_NUM_I2C && pyb_i2c_obj[i2c_id].i2c != NULL)) {
nlr_raise(mp_obj_new_exception_msg_varg(&mp_type_ValueError, "I2C bus %d does not exist", i2c_id + 1));
}
// get i2c object
const pyb_i2c_obj_t *i2c_obj = &pyb_i2c_obj[i2c_id];
// start the peripheral
i2c_init(i2c_obj->i2c);
return (mp_obj_t)i2c_obj;
}
// Check if an I2C device responds to the given address.
STATIC mp_obj_t pyb_i2c_is_ready(mp_obj_t self_in, mp_obj_t i2c_addr_o) {
pyb_i2c_obj_t *self = self_in;
machine_uint_t i2c_addr = mp_obj_get_int(i2c_addr_o) << 1;
for (int i = 0; i < 10; i++) {
HAL_StatusTypeDef status = HAL_I2C_IsDeviceReady(self->i2c, i2c_addr, 10, 200);
if (status == HAL_OK) {
return mp_const_true;
}
}
return mp_const_false;
}
STATIC MP_DEFINE_CONST_FUN_OBJ_2(pyb_i2c_is_ready_obj, pyb_i2c_is_ready);
// Scan all I2C addresses from 0x01 to 0x7f and return a list of those that respond.
STATIC mp_obj_t pyb_i2c_scan(mp_obj_t self_in) {
pyb_i2c_obj_t *self = self_in;
mp_obj_t list = mp_obj_new_list(0, NULL);
for (uint addr = 1; addr <= 127; addr++) {
for (int i = 0; i < 10; i++) {
HAL_StatusTypeDef status = HAL_I2C_IsDeviceReady(self->i2c, addr << 1, 10, 200);
if (status == HAL_OK) {
mp_obj_list_append(list, mp_obj_new_int(addr));
break;
}
}
}
return list;
}
STATIC MP_DEFINE_CONST_FUN_OBJ_1(pyb_i2c_scan_obj, pyb_i2c_scan);
STATIC mp_obj_t pyb_i2c_read(mp_obj_t self_in, mp_obj_t i2c_addr_in, mp_obj_t n_in) {
pyb_i2c_obj_t *self = self_in;
machine_uint_t i2c_addr = mp_obj_get_int(i2c_addr_in) << 1;
machine_uint_t n = mp_obj_get_int(n_in);
byte *data;
mp_obj_t o = mp_obj_str_builder_start(&mp_type_bytes, n, &data);
HAL_StatusTypeDef status = HAL_I2C_Master_Receive(self->i2c, i2c_addr, data, n, 500);
if (status != HAL_OK) {
// TODO really need a HardwareError object, or something
nlr_raise(mp_obj_new_exception_msg_varg(&mp_type_Exception, "HAL_I2C_Master_Receive failed with code %d", status));
}
return mp_obj_str_builder_end(o);
}
STATIC MP_DEFINE_CONST_FUN_OBJ_3(pyb_i2c_read_obj, pyb_i2c_read);
STATIC mp_obj_t pyb_i2c_write(mp_obj_t self_in, mp_obj_t i2c_addr_in, mp_obj_t data_in) {
pyb_i2c_obj_t *self = self_in;
machine_uint_t i2c_addr = mp_obj_get_int(i2c_addr_in) << 1;
HAL_StatusTypeDef status;
if (MP_OBJ_IS_INT(data_in)) {
uint8_t data[1] = {mp_obj_get_int(data_in)};
status = HAL_I2C_Master_Transmit(self->i2c, i2c_addr, data, 1, 500);
} else {
mp_buffer_info_t bufinfo;
mp_get_buffer_raise(data_in, &bufinfo, MP_BUFFER_READ);
status = HAL_I2C_Master_Transmit(self->i2c, i2c_addr, bufinfo.buf, bufinfo.len, 500);
}
if (status != HAL_OK) {
// TODO really need a HardwareError object, or something
nlr_raise(mp_obj_new_exception_msg_varg(&mp_type_Exception, "HAL_I2C_Master_Transmit failed with code %d", status));
}
return mp_const_none;
}
STATIC MP_DEFINE_CONST_FUN_OBJ_3(pyb_i2c_write_obj, pyb_i2c_write);
STATIC mp_obj_t pyb_i2c_mem_read(uint n_args, const mp_obj_t *args) {
pyb_i2c_obj_t *self = args[0];
machine_uint_t i2c_addr = mp_obj_get_int(args[1]) << 1;
machine_uint_t mem_addr = mp_obj_get_int(args[2]);
machine_uint_t n = mp_obj_get_int(args[3]);
byte *data;
mp_obj_t o = mp_obj_str_builder_start(&mp_type_bytes, n, &data);
HAL_StatusTypeDef status = HAL_I2C_Mem_Read(self->i2c, i2c_addr, mem_addr, I2C_MEMADD_SIZE_8BIT, data, n, 200);
//printf("Read got %d\n", status);
if (status != HAL_OK) {
// TODO really need a HardwareError object, or something
nlr_raise(mp_obj_new_exception_msg_varg(&mp_type_Exception, "HAL_I2C_Mem_Read failed with code %d", status));
}
return mp_obj_str_builder_end(o);
}
STATIC MP_DEFINE_CONST_FUN_OBJ_VAR_BETWEEN(pyb_i2c_mem_read_obj, 4, 4, pyb_i2c_mem_read);
STATIC mp_obj_t pyb_i2c_mem_write(uint n_args, const mp_obj_t *args) {
pyb_i2c_obj_t *self = args[0];
machine_uint_t i2c_addr = mp_obj_get_int(args[1]) << 1;
machine_uint_t mem_addr = mp_obj_get_int(args[2]);
HAL_StatusTypeDef status;
if (MP_OBJ_IS_INT(args[3])) {
uint8_t data[1] = {mp_obj_get_int(args[3])};
status = HAL_I2C_Mem_Write(self->i2c, i2c_addr, mem_addr, I2C_MEMADD_SIZE_8BIT, data, 1, 200);
} else {
mp_buffer_info_t bufinfo;
mp_get_buffer_raise(args[3], &bufinfo, MP_BUFFER_READ);
status = HAL_I2C_Mem_Write(self->i2c, i2c_addr, mem_addr, I2C_MEMADD_SIZE_8BIT, bufinfo.buf, bufinfo.len, 200);
}
//printf("Write got %d\n", status);
if (status != HAL_OK) {
// TODO really need a HardwareError object, or something
nlr_raise(mp_obj_new_exception_msg_varg(&mp_type_Exception, "HAL_I2C_Mem_Write failed with code %d", status));
}
return mp_const_none;
}
STATIC MP_DEFINE_CONST_FUN_OBJ_VAR_BETWEEN(pyb_i2c_mem_write_obj, 4, 4, pyb_i2c_mem_write);
STATIC const mp_map_elem_t pyb_i2c_locals_dict_table[] = {
{ MP_OBJ_NEW_QSTR(MP_QSTR_is_ready), (mp_obj_t)&pyb_i2c_is_ready_obj },
{ MP_OBJ_NEW_QSTR(MP_QSTR_scan), (mp_obj_t)&pyb_i2c_scan_obj },
{ MP_OBJ_NEW_QSTR(MP_QSTR_read), (mp_obj_t)&pyb_i2c_read_obj },
{ MP_OBJ_NEW_QSTR(MP_QSTR_write), (mp_obj_t)&pyb_i2c_write_obj },
{ MP_OBJ_NEW_QSTR(MP_QSTR_mem_read), (mp_obj_t)&pyb_i2c_mem_read_obj },
{ MP_OBJ_NEW_QSTR(MP_QSTR_mem_write), (mp_obj_t)&pyb_i2c_mem_write_obj },
};
STATIC MP_DEFINE_CONST_DICT(pyb_i2c_locals_dict, pyb_i2c_locals_dict_table);
const mp_obj_type_t pyb_i2c_type = {
{ &mp_type_type },
.name = MP_QSTR_I2C,
.make_new = pyb_i2c_make_new,
.locals_dict = (mp_obj_t)&pyb_i2c_locals_dict,
};