From 5b3468ebb39ccdb287711d6eca163fada2bb8cf0 Mon Sep 17 00:00:00 2001
From: laokaiyao <laokaiyao@espressif.com>
Date: Mon, 18 Apr 2022 14:42:26 +0800
Subject: [PATCH] i2c: support i2c on esp32h2

---
 components/driver/test/test_i2c.c             | 22 +++++++++++--------
 .../soc/esp32h2/include/rev2/soc/clkrst_reg.h |  6 +++++
 .../peripherals/i2c/i2c_self_test/README.md   |  2 +-
 examples/peripherals/i2c/i2c_simple/README.md |  2 +-
 4 files changed, 21 insertions(+), 11 deletions(-)

diff --git a/components/driver/test/test_i2c.c b/components/driver/test/test_i2c.c
index fa601fc510..0dc6324b1f 100644
--- a/components/driver/test/test_i2c.c
+++ b/components/driver/test/test_i2c.c
@@ -31,7 +31,7 @@
 #define RW_TEST_LENGTH       129  /*!<Data length for r/w test, any value from 0-DATA_LENGTH*/
 #define DELAY_TIME_BETWEEN_ITEMS_MS   1234 /*!< delay time between different test items */
 
-#if CONFIG_IDF_TARGET_ESP32C3 || CONFIG_IDF_TARGET_ESP32S3
+#if CONFIG_IDF_TARGET_ESP32C3 || CONFIG_IDF_TARGET_ESP32S3 || CONFIG_IDF_TARGET_ESP32H2
 #define I2C_SLAVE_SCL_IO     5     /*!<gpio number for i2c slave clock  */
 #define I2C_SLAVE_SDA_IO     6     /*!<gpio number for i2c slave data */
 #else
@@ -43,7 +43,7 @@
 #define I2C_SLAVE_TX_BUF_LEN  (2*DATA_LENGTH) /*!<I2C slave tx buffer size */
 #define I2C_SLAVE_RX_BUF_LEN  (2*DATA_LENGTH) /*!<I2C slave rx buffer size */
 
-#if CONFIG_IDF_TARGET_ESP32C3
+#if CONFIG_IDF_TARGET_ESP32C3 || CONFIG_IDF_TARGET_ESP32H2
 #define I2C_MASTER_SCL_IO     5     /*!<gpio number for i2c master clock  */
 #define I2C_MASTER_SDA_IO     6     /*!<gpio number for i2c master data */
 #elif CONFIG_IDF_TARGET_ESP32S3
@@ -658,13 +658,12 @@ TEST_CASE("I2C general API test", "[i2c]")
     }
 }
 
-#if !TEMPORARY_DISABLED_FOR_TARGETS(ESP32S3, ESP32C3, ESP32C2)
 //Init uart baud rate detection
 static void uart_aut_baud_det_init(int rxd_io_num)
 {
     gpio_hal_iomux_func_sel(GPIO_PIN_MUX_REG[rxd_io_num], PIN_FUNC_GPIO);
     gpio_set_direction(rxd_io_num, GPIO_MODE_INPUT_OUTPUT);
-    esp_rom_gpio_connect_out_signal(rxd_io_num, I2CEXT1_SCL_OUT_IDX, 0, 0);
+    esp_rom_gpio_connect_out_signal(rxd_io_num, I2CEXT0_SCL_OUT_IDX, 0, 0);
     esp_rom_gpio_connect_in_signal(rxd_io_num, U1RXD_IN_IDX, 0);
     periph_module_enable(PERIPH_UART1_MODULE);
     /* Reset all the bits */
@@ -676,15 +675,22 @@ static void uart_aut_baud_det_init(int rxd_io_num)
 //Calculate I2C scl freq
 static void i2c_scl_freq_cal(void)
 {
+#if CONFIG_IDF_TARGET_ESP32 || CONFIG_IDF_TARGET_ESP32S2
     const int i2c_source_clk_freq = 80000000;
     const float i2c_cource_clk_period = 0.0125;
+    int expt_cnt = 542;
+#else
+    const int i2c_source_clk_freq = 18000000; // Clock sorce: RTC
+    const float i2c_cource_clk_period = 0.056;
+    int expt_cnt = 540;
+#endif
     int edg_cnt = uart_ll_get_rxd_edge_cnt(&UART1);
     int pospulse_cnt = uart_ll_get_pos_pulse_cnt(&UART1);
     int negpulse_cnt = uart_ll_get_neg_pulse_cnt(&UART1);
     int high_period_cnt = uart_ll_get_high_pulse_cnt(&UART1);
     int low_period_cnt = uart_ll_get_low_pulse_cnt(&UART1);
-    if(edg_cnt != 542) {
-        printf("\nedg_cnt != 542, test fail\n");
+    if(edg_cnt != expt_cnt) {
+        printf("\nedg_cnt != %d, test fail\n", expt_cnt);
         return;
     }
     printf("\nDetected SCL frequency: %d Hz\n", i2c_source_clk_freq / ((pospulse_cnt + negpulse_cnt) / 2) );
@@ -697,7 +703,7 @@ static void i2c_scl_freq_cal(void)
 TEST_CASE("I2C SCL freq test (local test)", "[i2c][ignore]")
 {
     //Use the UART baud rate detection function to detect the I2C SCL frequency.
-    const int i2c_num = 1;
+    const int i2c_num = 0;
     const int uart1_rxd_io = 5;
     i2c_config_t conf_master = {
         .mode = I2C_MODE_MASTER,
@@ -723,6 +729,4 @@ TEST_CASE("I2C SCL freq test (local test)", "[i2c][ignore]")
     TEST_ESP_OK(i2c_driver_delete(i2c_num));
 }
 
-#endif // TEMPORARY_DISABLED_FOR_TARGETS(ESP32S3, ESP32C3)
-
 #endif // SOC_I2C_SUPPORT_SLAVE
diff --git a/components/soc/esp32h2/include/rev2/soc/clkrst_reg.h b/components/soc/esp32h2/include/rev2/soc/clkrst_reg.h
index cfd7be54da..5ab1aad5ea 100644
--- a/components/soc/esp32h2/include/rev2/soc/clkrst_reg.h
+++ b/components/soc/esp32h2/include/rev2/soc/clkrst_reg.h
@@ -49,6 +49,12 @@ extern "C" {
 #define SYSTEM_CPU_DIV_NUM_M  (SYSTEM_CPU_DIV_NUM_V << SYSTEM_CPU_DIV_NUM_S)
 #define SYSTEM_CPU_DIV_NUM_V  0x000000FFU
 #define SYSTEM_CPU_DIV_NUM_S  0
+
+#define SYSTEM_PRE_DIV_CNT  SYSTEM_CPU_DIV_NUM
+#define SYSTEM_PRE_DIV_CNT_M  SYSTEM_CPU_DIV_NUM_M
+#define SYSTEM_PRE_DIV_CNT_V  SYSTEM_CPU_DIV_NUM_V
+#define SYSTEM_PRE_DIV_CNT_S  SYSTEM_CPU_DIV_NUM_S
+
 /** SYSTEM_CPU_DIV_NUMERATOR : R/W; bitpos: [13:8]; default: 0;
  *  Need add description
  */
diff --git a/examples/peripherals/i2c/i2c_self_test/README.md b/examples/peripherals/i2c/i2c_self_test/README.md
index 38e3704434..7734c34b9f 100644
--- a/examples/peripherals/i2c/i2c_self_test/README.md
+++ b/examples/peripherals/i2c/i2c_self_test/README.md
@@ -81,7 +81,7 @@ To run this example, you should have one ESP development board (e.g. ESP32-WROVE
 - Connection:
   - connect SDA/SCL of BH1750 sensor to GPIO5/GPIO6
 
-**Note:** There is only one i2c device on esp32c3, so you can't try any master-slave example for esp32/s2 in this repo. But you can try external devices. If you find anything wrong with your device, please try connecting pull-up resistors by yourself.
+**Note:** There is only one i2c device on ESP32-C3/ESP32-C2/ESP32-H2, so it is not possible to perform any ESP32/ESP32-S2 self-test example from this repo. However it is possible to test I2C with external devices. If you find anything wrong with your device, please try connecting external pull-up resistors.
 
 ### Configure the project
 
diff --git a/examples/peripherals/i2c/i2c_simple/README.md b/examples/peripherals/i2c/i2c_simple/README.md
index 4b4287d022..9309a8356b 100644
--- a/examples/peripherals/i2c/i2c_simple/README.md
+++ b/examples/peripherals/i2c/i2c_simple/README.md
@@ -12,7 +12,7 @@ If you have a new I2C application to go (for example, read the temperature data
 
 ### Hardware Required
 
-To run this example, you should have one ESP32, ESP32-S or ESP32-C based development board as well as a MPU9250. MPU9250 is a inertial measurement unit, which contains a accelerometer, gyroscope as well as a magnetometer, for more information about it, you can read the [datasheet of the MPU9250 sensor](https://invensense.tdk.com/wp-content/uploads/2015/02/PS-MPU-9250A-01-v1.1.pdf).
+To run this example, you should have one ESP32, ESP32-S, ESP32-C or ESP32-H based development board as well as a MPU9250. MPU9250 is a inertial measurement unit, which contains a accelerometer, gyroscope as well as a magnetometer, for more information about it, you can read the [datasheet of the MPU9250 sensor](https://invensense.tdk.com/wp-content/uploads/2015/02/PS-MPU-9250A-01-v1.1.pdf).
 
 #### Pin Assignment: