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trezor-firmware/core/embed/trezorhal/i2c.c

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#include STM32_HAL_H
#include TREZOR_BOARD
#include "i2c.h"
#include "common.h"
static I2C_HandleTypeDef i2c_handle;
void HAL_I2C_MspInit(I2C_HandleTypeDef *hi2c) {
// enable I2C clock
I2C_INSTANCE_CLK_EN();
I2C_INSTANCE_SCL_CLK_EN();
I2C_INSTANCE_SDA_CLK_EN();
}
void HAL_I2C_MspDeInit(I2C_HandleTypeDef *hi2c) {
// disable I2C clock
I2C_INSTANCE_CLK_DIS();
}
void i2c_init(void) {
if (i2c_handle.Instance) {
return;
}
HAL_I2C_MspInit(&i2c_handle);
GPIO_InitTypeDef GPIO_InitStructure;
// configure CTP I2C SCL and SDA GPIO lines
GPIO_InitStructure.Mode = GPIO_MODE_AF_OD;
GPIO_InitStructure.Pull = GPIO_NOPULL;
GPIO_InitStructure.Speed =
GPIO_SPEED_FREQ_LOW; // I2C is a KHz bus and low speed is still good into
// the low MHz
GPIO_InitStructure.Alternate = I2C_INSTANCE_PIN_AF;
GPIO_InitStructure.Pin = I2C_INSTANCE_SCL_PIN;
HAL_GPIO_Init(I2C_INSTANCE_SCL_PORT, &GPIO_InitStructure);
GPIO_InitStructure.Alternate = I2C_INSTANCE_PIN_AF;
GPIO_InitStructure.Pin = I2C_INSTANCE_SDA_PIN;
HAL_GPIO_Init(I2C_INSTANCE_SDA_PORT, &GPIO_InitStructure);
i2c_handle.Instance = I2C_INSTANCE;
i2c_handle.Init.ClockSpeed = 200000;
i2c_handle.Init.DutyCycle = I2C_DUTYCYCLE_16_9;
i2c_handle.Init.OwnAddress1 = 0xFE; // master
i2c_handle.Init.AddressingMode = I2C_ADDRESSINGMODE_7BIT;
i2c_handle.Init.DualAddressMode = I2C_DUALADDRESS_DISABLE;
i2c_handle.Init.OwnAddress2 = 0;
i2c_handle.Init.GeneralCallMode = I2C_GENERALCALL_DISABLE;
i2c_handle.Init.NoStretchMode = I2C_NOSTRETCH_DISABLE;
if (HAL_OK != HAL_I2C_Init(&i2c_handle)) {
ensure(secfalse, "I2C was not loaded properly.");
return;
}
}
void _i2c_deinit(void) {
if (i2c_handle.Instance) {
HAL_I2C_DeInit(&i2c_handle);
i2c_handle.Instance = NULL;
}
}
void _i2c_ensure_pin(GPIO_TypeDef *port, uint16_t GPIO_Pin,
GPIO_PinState PinState) {
HAL_GPIO_WritePin(port, GPIO_Pin, PinState);
while (HAL_GPIO_ReadPin(port, GPIO_Pin) != PinState)
;
}
// I2C cycle described in section 2.9.7 of STM CD00288116 Errata sheet
//
// https://www.st.com/content/ccc/resource/technical/document/errata_sheet/7f/05/b0/bc/34/2f/4c/21/CD00288116.pdf/files/CD00288116.pdf/jcr:content/translations/en.CD00288116.pdf
void i2c_cycle(void) {
// PIN6 is SCL, PIN7 is SDA
// 1. Disable I2C peripheral
_i2c_deinit();
// 2. Configure SCL/SDA as GPIO OUTPUT Open Drain
GPIO_InitTypeDef GPIO_InitStructure;
GPIO_InitStructure.Mode = GPIO_MODE_OUTPUT_OD;
GPIO_InitStructure.Pull = GPIO_NOPULL;
GPIO_InitStructure.Speed = GPIO_SPEED_FREQ_LOW;
GPIO_InitStructure.Pin = I2C_INSTANCE_SDA_PIN;
HAL_GPIO_Init(I2C_INSTANCE_SDA_PORT, &GPIO_InitStructure);
GPIO_InitStructure.Pin = I2C_INSTANCE_SCL_PIN;
HAL_GPIO_Init(I2C_INSTANCE_SCL_PORT, &GPIO_InitStructure);
HAL_Delay(50);
// 3. Check SCL and SDA High level
_i2c_ensure_pin(I2C_INSTANCE_SCL_PORT, I2C_INSTANCE_SCL_PIN, GPIO_PIN_SET);
_i2c_ensure_pin(I2C_INSTANCE_SDA_PORT, I2C_INSTANCE_SDA_PIN, GPIO_PIN_SET);
// 4+5. Check SDA Low level
_i2c_ensure_pin(I2C_INSTANCE_SDA_PORT, I2C_INSTANCE_SDA_PIN, GPIO_PIN_RESET);
// 6+7. Check SCL Low level
_i2c_ensure_pin(I2C_INSTANCE_SCL_PORT, I2C_INSTANCE_SCL_PIN, GPIO_PIN_RESET);
// 8+9. Check SCL High level
_i2c_ensure_pin(I2C_INSTANCE_SCL_PORT, I2C_INSTANCE_SCL_PIN, GPIO_PIN_SET);
// 10+11. Check SDA High level
_i2c_ensure_pin(I2C_INSTANCE_SDA_PORT, I2C_INSTANCE_SDA_PIN, GPIO_PIN_SET);
// 12. Configure SCL/SDA as Alternate function Open-Drain
GPIO_InitStructure.Mode = GPIO_MODE_AF_OD;
GPIO_InitStructure.Pull = GPIO_NOPULL;
GPIO_InitStructure.Speed = GPIO_SPEED_FREQ_LOW;
GPIO_InitStructure.Alternate = I2C_INSTANCE_PIN_AF;
GPIO_InitStructure.Pin = I2C_INSTANCE_SCL_PIN;
HAL_GPIO_Init(I2C_INSTANCE_SCL_PORT, &GPIO_InitStructure);
GPIO_InitStructure.Pin = I2C_INSTANCE_SDA_PIN;
HAL_GPIO_Init(I2C_INSTANCE_SDA_PORT, &GPIO_InitStructure);
HAL_Delay(50);
// 13. Set SWRST bit in I2Cx_CR1 register
I2C_INSTANCE_FORCE_RESET();
HAL_Delay(50);
// 14. Clear SWRST bit in I2Cx_CR1 register
I2C_INSTANCE_RELEASE_RESET();
// 15. Enable the I2C peripheral
i2c_init();
HAL_Delay(10);
}
HAL_StatusTypeDef i2c_transmit(uint8_t addr, uint8_t *data, uint16_t len,
uint32_t timeout) {
return HAL_I2C_Master_Transmit(&i2c_handle, addr, data, len, timeout);
}
HAL_StatusTypeDef i2c_receive(uint8_t addr, uint8_t *data, uint16_t len,
uint32_t timeout) {
return HAL_I2C_Master_Receive(&i2c_handle, addr, data, len, timeout);
}
HAL_StatusTypeDef i2c_mem_write(uint8_t addr, uint16_t mem_addr,
uint16_t mem_addr_size, uint8_t *data,
uint16_t len, uint32_t timeout) {
return HAL_I2C_Mem_Write(&i2c_handle, addr, mem_addr, mem_addr_size, data,
len, timeout);
}
HAL_StatusTypeDef i2c_mem_read(uint8_t addr, uint16_t mem_addr,
uint16_t mem_addr_size, uint8_t *data,
uint16_t len, uint32_t timeout) {
return HAL_I2C_Mem_Read(&i2c_handle, addr, mem_addr, mem_addr_size, data, len,
timeout);
}