From bcf7608cf812e9140e5ac2dcb4ad4afd53fdbca7 Mon Sep 17 00:00:00 2001 From: John <32036524+jkearins@users.noreply.github.com> Date: Fri, 28 Jan 2022 19:20:42 +0300 Subject: [PATCH] i2c: Enable I2C Slave mode with input-only pin as SCL. Merges https://github.com/espressif/esp-idf/pull/8312 If we use I2C in slave mode, we can use input-only pin for SCL line (GPI 34-39). But there is a problem in i2c_set_pin() which is called by i2c_param_config(). In case of using GPI as SCL the following statements are failed: 1. gpio_set_level(scl_io_num, I2C_IO_INIT_LEVEL); Function fails because it cannot set level for input pin. As a result a ESP_LOGE() is called. 2. gpio_set_direction(scl_io_num, GPIO_MODE_INPUT_OUTPUT_OD); Function fails because it accepts only GPIO pins. ESP_LOGE() is called, input mode is not enabled for the pin and as a result - no interrupts from the pin. --- components/driver/i2c.c | 13 +++++++++---- 1 file changed, 9 insertions(+), 4 deletions(-) diff --git a/components/driver/i2c.c b/components/driver/i2c.c index ebea59990a..22282a75df 100644 --- a/components/driver/i2c.c +++ b/components/driver/i2c.c @@ -871,10 +871,15 @@ esp_err_t i2c_set_pin(i2c_port_t i2c_num, int sda_io_num, int scl_io_num, bool s esp_rom_gpio_connect_in_signal(sda_io_num, sda_in_sig, 0); } if (scl_io_num >= 0) { - gpio_set_level(scl_io_num, I2C_IO_INIT_LEVEL); - gpio_hal_iomux_func_sel(GPIO_PIN_MUX_REG[scl_io_num], PIN_FUNC_GPIO); - gpio_set_direction(scl_io_num, GPIO_MODE_INPUT_OUTPUT_OD); - esp_rom_gpio_connect_out_signal(scl_io_num, scl_out_sig, 0, 0); + if (mode == I2C_MODE_MASTER) { + gpio_set_level(scl_io_num, I2C_IO_INIT_LEVEL); + gpio_hal_iomux_func_sel(GPIO_PIN_MUX_REG[scl_io_num], PIN_FUNC_GPIO); + gpio_set_direction(scl_io_num, GPIO_MODE_INPUT_OUTPUT_OD); + esp_rom_gpio_connect_out_signal(scl_io_num, scl_out_sig, 0, 0); + } else { + gpio_hal_iomux_func_sel(GPIO_PIN_MUX_REG[scl_io_num], PIN_FUNC_GPIO); + gpio_set_direction(scl_io_num, GPIO_MODE_INPUT); + } esp_rom_gpio_connect_in_signal(scl_io_num, scl_in_sig, 0); if (scl_pullup_en == GPIO_PULLUP_ENABLE) { gpio_set_pull_mode(scl_io_num, GPIO_PULLUP_ONLY);