Commit 34fe5a30 authored by Dave Hylands's avatar Dave Hylands Committed by Damien George
Browse files

stmhal: Enable I2C support for F7 MCUs.

parent 26664dd1
......@@ -47,6 +47,19 @@ void STM32F7DISC_board_early_init(void);
#define MICROPY_HW_I2C1_SCL (pin_B8)
#define MICROPY_HW_I2C1_SDA (pin_B9)
#define MICROPY_HW_I2C3_SCL (pin_H7)
#define MICROPY_HW_I2C3_SDA (pin_H8)
// The STM32F7 uses a TIMINGR register which is configured using an Excel
// Spreadsheet from AN4235: http://www.st.com/web/en/catalog/tools/PF258335
// We use an array of baudrates and corresponding TIMINGR values.
//
// The value 0x40912732 was obtained from the DISCOVERY_I2Cx_TIMING constant
// defined in the STM32F7Cube file Drivers/BSP/STM32F746G-Discovery/stm32f7456g_discovery.h
#define MICROPY_HW_I2C_BAUDRATE_TIMING {{100000, 0x40912732}}
#define MICROPY_HW_I2C_BAUDRATE_DEFAULT 100000
#define MICROPY_HW_I2C_BAUDRATE_MAX 100000
// USRSW is pulled low. Pressing the button makes the input go high.
#define MICROPY_HW_USRSW_PIN (pin_I11)
#define MICROPY_HW_USRSW_PULL (GPIO_NOPULL)
......
......@@ -26,12 +26,16 @@ TP1,PH2
TP2,PI8
TP3,PH15
AUDIO_INT,PD6
AUDIO_SDA,PH8
AUDIO_SCL,PH7
EXT_SDA,PB9
EXT_SCL,PB8
EXT_RST,PG3
SD_SW,PC13
LCD_BL_CTRL,PK3
LCD_INT,PI13
LCD_SDA,PH8
LCD_SCL,PH7
OTG_FS_POWER,PD5
OTG_FS_OVER_CURRENT,PD4
OTG_HS_OVER_CURRENT,PE3
......
......@@ -37,9 +37,21 @@
#include "i2c.h"
#include MICROPY_HAL_H
#if !defined(STM32F7)
// The STM32F7 has Timing, where the F4 has ClockSpeed and DutyCycle, so we
// need to figure that out before we can enable i2c
#if !defined(MICROPY_HW_I2C_BAUDRATE_DEFAULT)
#define MICROPY_HW_I2C_BAUDRATE_DEFAULT 400000
#endif
#if !defined(MICROPY_HW_I2C_BAUDRATE_MAX)
#define MICROPY_HW_I2C_BAUDRATE_MAX 400000
#endif
#if !defined(I2C_NOSTRETCH_DISABLE)
// Assumes that the F7 firmware is newer, so the F4 firmware will eventually
// catchup. I2C_NOSTRETCH_DISABLED was renamed to I2C_NOSTRETCH_DISABLE
// in the F7 so we use the F7 constant and provide a backwards compatabilty
// #define here.
#define I2C_NOSTRETCH_DISABLE I2C_NOSTRETCH_DISABLED
#endif
/// \moduleref pyb
/// \class I2C - a two-wire serial protocol
......@@ -138,6 +150,50 @@ STATIC const pyb_i2c_obj_t pyb_i2c_obj[] = {
#endif
};
#if defined(MICROPY_HW_I2C_BAUDRATE_TIMING)
// The STM32F0, F3, and F7 use a TIMINGR register rather than ClockSpeed and
// DutyCycle.
STATIC const struct {
uint32_t baudrate;
uint32_t timing;
} pyb_i2c_baudrate_timing[] = MICROPY_HW_I2C_BAUDRATE_TIMING;
#define NUM_BAUDRATE_TIMINGS MP_ARRAY_SIZE(pyb_i2c_baudrate_timing)
STATIC void i2c_set_baudrate(I2C_InitTypeDef *init, uint32_t baudrate) {
for (int i = 0; i < NUM_BAUDRATE_TIMINGS; i++) {
if (pyb_i2c_baudrate_timing[i].baudrate == baudrate) {
init->Timing = pyb_i2c_baudrate_timing[i].timing;
return;
}
}
nlr_raise(mp_obj_new_exception_msg_varg(&mp_type_ValueError,
"Unsupported I2C baudrate: %lu", baudrate));
}
STATIC uint32_t i2c_get_baudrate(I2C_InitTypeDef *init) {
for (int i = 0; i < NUM_BAUDRATE_TIMINGS; i++) {
if (pyb_i2c_baudrate_timing[i].timing == init->Timing) {
return pyb_i2c_baudrate_timing[i].baudrate;
}
}
return 0;
}
#else
STATIC void i2c_set_baudrate(I2C_InitTypeDef *init, uint32_t baudrate) {
init->ClockSpeed = baudrate;
init->DutyCycle = I2C_DUTYCYCLE_16_9;
}
STATIC uint32_t i2c_get_baudrate(I2C_InitTypeDef *init) {
return init->ClockSpeed;
}
#endif // MICROPY_HW_I2C_BAUDRATE_TIMING
void i2c_init0(void) {
// reset the I2C1 handles
#if defined(MICROPY_HW_I2C1_SCL)
......@@ -276,7 +332,7 @@ STATIC void pyb_i2c_print(const mp_print_t *print, mp_obj_t self_in, mp_print_ki
mp_printf(print, "I2C(%u)", i2c_num);
} else {
if (in_master_mode(self)) {
mp_printf(print, "I2C(%u, I2C.MASTER, baudrate=%u)", i2c_num, self->i2c->Init.ClockSpeed);
mp_printf(print, "I2C(%u, I2C.MASTER, baudrate=%u)", i2c_num, i2c_get_baudrate(&self->i2c->Init));
} else {
mp_printf(print, "I2C(%u, I2C.SLAVE, addr=0x%02x)", i2c_num, (self->i2c->Instance->OAR1 >> 1) & 0x7f);
}
......@@ -295,7 +351,7 @@ STATIC mp_obj_t pyb_i2c_init_helper(const pyb_i2c_obj_t *self, mp_uint_t n_args,
static const mp_arg_t allowed_args[] = {
{ MP_QSTR_mode, MP_ARG_REQUIRED | MP_ARG_INT, {.u_int = 0} },
{ MP_QSTR_addr, MP_ARG_KW_ONLY | MP_ARG_INT, {.u_int = 0x12} },
{ MP_QSTR_baudrate, MP_ARG_KW_ONLY | MP_ARG_INT, {.u_int = 400000} },
{ MP_QSTR_baudrate, MP_ARG_KW_ONLY | MP_ARG_INT, {.u_int = MICROPY_HW_I2C_BAUDRATE_DEFAULT} },
{ MP_QSTR_gencall, MP_ARG_KW_ONLY | MP_ARG_BOOL, {.u_bool = false} },
};
......@@ -313,13 +369,13 @@ STATIC mp_obj_t pyb_i2c_init_helper(const pyb_i2c_obj_t *self, mp_uint_t n_args,
init->OwnAddress1 = (args[1].u_int << 1) & 0xfe;
}
i2c_set_baudrate(init, MIN(args[2].u_int, MICROPY_HW_I2C_BAUDRATE_MAX));
init->AddressingMode = I2C_ADDRESSINGMODE_7BIT;
init->ClockSpeed = MIN(args[2].u_int, 400000);
init->DualAddressMode = I2C_DUALADDRESS_DISABLED;
init->DutyCycle = I2C_DUTYCYCLE_16_9;
init->GeneralCallMode = args[3].u_bool ? I2C_GENERALCALL_ENABLED : I2C_GENERALCALL_DISABLED;
init->NoStretchMode = I2C_NOSTRETCH_DISABLED;
init->OwnAddress2 = 0xfe; // unused
init->OwnAddress2 = 0; // unused
init->NoStretchMode = I2C_NOSTRETCH_DISABLE;
// init the I2C bus
i2c_init(self->i2c);
......@@ -753,5 +809,3 @@ const mp_obj_type_t pyb_i2c_type = {
.make_new = pyb_i2c_make_new,
.locals_dict = (mp_obj_t)&pyb_i2c_locals_dict,
};
#endif // STM32F7
......@@ -471,8 +471,8 @@ soft_reset:
rng_init0();
#endif
#if !defined(STM32F7) // Temp hack
i2c_init0();
#if !defined(STM32F7) // Temp hack
spi_init0();
#endif
pyb_usb_init0();
......
......@@ -589,8 +589,8 @@ STATIC const mp_map_elem_t pyb_module_globals_table[] = {
#if defined(MICROPY_HW_LED1)
{ MP_OBJ_NEW_QSTR(MP_QSTR_LED), (mp_obj_t)&pyb_led_type },
#endif
#if !defined(STM32F7) // Temp hack
{ MP_OBJ_NEW_QSTR(MP_QSTR_I2C), (mp_obj_t)&pyb_i2c_type },
#if !defined(STM32F7) // Temp hack
{ MP_OBJ_NEW_QSTR(MP_QSTR_SPI), (mp_obj_t)&pyb_spi_type },
#endif
{ MP_OBJ_NEW_QSTR(MP_QSTR_UART), (mp_obj_t)&pyb_uart_type },
......
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