I2C Fails on STM32U585 and No Clock Signal

[DhaferAlzhrani]

Describe the bug

When using I2C on the STM32U585 with Zephyr RTOS, the I2C communication fails with a TIMEOUT error during a write operation. The Logic Analyzer shows no activity on the clock line (SCL) and only a single pulse on the data line (SDA). The observed output is as follows:

Channel 0 (SCL): No activity.
Channel 1 (SDA): Single pulse.

To Reproduce

1.Configure the I2C1 peripheral in the device tree as follows:

config:

CONFIG_I2C_STM32_INTERRUPT=y
CONFIG_I2C=y
CONFIG_I2C_STM32=y
CONFIG_I2C_LOG_LEVEL_DBG=y
CONFIG_ASSERT=y

device tree:

&i2c1 {
    compatible = "st,stm32-i2c-v2";
    clock-frequency = <0x186a0>;  // 100 kHz
    #address-cells = <0x1>;
    #size-cells = <0x0>;
    reg = <0x40005400 0x400>;
    clocks = <&rcc 0x9c 0x200000>;
    interrupts = <0x37 0x0>, <0x38 0x0>;
    interrupt-names = "event", "error";
    status = "okay";
    pinctrl-0 = <&i2c1_sda_pb7 &i2c1_scl_pb6>;
    pinctrl-names = "default";
};
&pll1 {
    div-m = <1>;
    mul-n = <80>;
    div-q = <2>;
    div-r = <2>;
    clocks = <&clk_msis>;
    status = "okay";
};
&rcc {
    clocks = <&pll1>;
    clock-frequency = <DT_FREQ_M(160)>;  // 160 MHz
    ahb-prescaler = <1>;
    apb1-prescaler = <8>;  // 20 MHz
    apb2-prescaler = <8>;  // 20 MHz
    apb3-prescaler = <1>;
};

2.Ensure that PB6 (SCL) and PB7 (SDA) are properly routed and configured with pull-up resistors on board.

3.Execute a basic i2c_write operation in the application:

uint8_t data[] = {0x01, 0x42}; 
int ret = i2c_write(i2c_dev, data, sizeof(data), 0x48); 

4.Observe the system logs and the Logic Analyzer output.

Expected behavior
The I2C master should generate a complete sequence, including:
A Start Condition on SDA.
Clock pulses on SCL.
The slave address followed by data bytes.

Logs and console output

<dbg> i2c_ll_stm32_v2: stm32_i2c_msg_write: stm32_i2c_msg_write: TIMEOUT
I2C write error: -5

Environment:
MCU: STM32U585
Zephyr Version: 3.6.99

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