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core: reset i2c bus when detected busy

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matejcik 2019-06-03 17:02:20 +02:00 committed by Pavol Rusnak
parent 50cb440d9a
commit bf79384845
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GPG Key ID: 91F3B339B9A02A3D
1 changed files with 84 additions and 12 deletions
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96
core/embed/trezorhal/touch_t.h
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@ -91,16 +91,11 @@ void HAL_I2C_MspDeInit(I2C_HandleTypeDef *hi2c) {
__HAL_RCC_I2C1_CLK_DISABLE();
}
void touch_power_on(void) {
static void _i2c_init(void) {
if (i2c_handle.Instance) {
return;
}
// turn on CTP circuitry
touch_active_pin_state();
HAL_Delay(50);
// I2C device interface configuration
i2c_handle.Instance = I2C1;
i2c_handle.Init.ClockSpeed = 400000;
i2c_handle.Init.DutyCycle = I2C_DUTYCYCLE_16_9;
@ -115,6 +110,84 @@ void touch_power_on(void) {
ensure(secfalse, NULL);
return;
}
}
static void _i2c_deinit(void) {
if (i2c_handle.Instance) {
HAL_I2C_DeInit(&i2c_handle);
i2c_handle.Instance = NULL;
}
}
static void _i2c_ensure_pin(uint16_t GPIO_Pin, GPIO_PinState PinState) {
HAL_GPIO_WritePin(GPIOB, GPIO_Pin, PinState);
while (HAL_GPIO_ReadPin(GPIOB, 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
static 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 = GPIO_PIN_6 | GPIO_PIN_7;
HAL_GPIO_Init(GPIOB, &GPIO_InitStructure);
HAL_Delay(50);
// 3. Check SCL and SDA High level
_i2c_ensure_pin(GPIO_PIN_6, GPIO_PIN_SET);
_i2c_ensure_pin(GPIO_PIN_7, GPIO_PIN_SET);
// 4+5. Check SDA Low level
_i2c_ensure_pin(GPIO_PIN_7, GPIO_PIN_RESET);
// 6+7. Check SCL Low level
_i2c_ensure_pin(GPIO_PIN_6, GPIO_PIN_RESET);
// 8+9. Check SCL High level
_i2c_ensure_pin(GPIO_PIN_6, GPIO_PIN_SET);
// 10+11. Check SDA High level
_i2c_ensure_pin(GPIO_PIN_7, 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 = GPIO_AF4_I2C1;
GPIO_InitStructure.Pin = GPIO_PIN_6 | GPIO_PIN_7;
HAL_GPIO_Init(GPIOB, &GPIO_InitStructure);
HAL_Delay(50);
// 13. Set SWRST bit in I2Cx_CR1 register
__HAL_RCC_I2C1_FORCE_RESET();
HAL_Delay(50);
// 14. Clear SWRST bit in I2Cx_CR1 register
__HAL_RCC_I2C1_RELEASE_RESET();
// 15. Enable the I2C peripheral
_i2c_init();
HAL_Delay(10);
}
void touch_power_on(void) {
if (i2c_handle.Instance) {
return;
}
// turn on CTP circuitry
touch_active_pin_state();
HAL_Delay(50);
// I2C device interface configuration
_i2c_init();
// set register 0xA4 G_MODE to interrupt polling mode (0x00). basically, CTPM
// keeps this input line (to PC4) low while a finger is on the screen.
@ -129,10 +202,7 @@ void touch_power_on(void) {
}
void touch_power_off(void) {
if (i2c_handle.Instance) {
HAL_I2C_DeInit(&i2c_handle);
i2c_handle.Instance = NULL;
}
_i2c_deinit();
// turn off CTP circuitry
HAL_Delay(50);
touch_default_pin_state();
@ -175,8 +245,10 @@ uint32_t touch_read(void) {
}
uint8_t outgoing[] = {0x00}; // start reading from address 0x00
if (HAL_OK != HAL_I2C_Master_Transmit(&i2c_handle, TOUCH_ADDRESS, outgoing,
sizeof(outgoing), 1)) {
int result = HAL_I2C_Master_Transmit(&i2c_handle, TOUCH_ADDRESS, outgoing,
sizeof(outgoing), 1);
if (result != HAL_OK) {
if (result == HAL_BUSY) _i2c_cycle();
return 0;
}