What: /sys/bus/i2c/devices/-/unlock Date: 2025-07-04 KernelVersion: 6.17 Contact: Abd-Alrhman Masalkhi Description: Write-only attribute used to present a password and unlock access to protected areas of the M24LR chip, including configuration registers such as the Sector Security Status (SSS) bytes. A valid password must be written to enable write access to these regions via the I2C interface. Format: - Hexadecimal string representing a 32-bit (4-byte) password - Accepts 1 to 8 hex digits (e.g., "c", "1F", "a1b2c3d4") - No "0x" prefix, whitespace, or trailing newline - Case-insensitive Behavior: - If the password matches the internal stored value, access to protected memory/configuration is granted - If the password does not match the internally stored value, it will fail silently What: /sys/bus/i2c/devices/-/new_pass Date: 2025-07-04 KernelVersion: 6.17 Contact: Abd-Alrhman Masalkhi Description: Write-only attribute used to update the password required to unlock the M24LR chip. Format: - Hexadecimal string representing a new 32-bit password - Accepts 1 to 8 hex digits (e.g., "1A", "ffff", "c0ffee00") - No "0x" prefix, whitespace, or trailing newline - Case-insensitive Behavior: - Overwrites the current password stored in the I2C password register - Requires the device to be unlocked before changing the password - If the device is locked, the write silently fails What: /sys/bus/i2c/devices/-/uid Date: 2025-07-04 KernelVersion: 6.17 Contact: Abd-Alrhman Masalkhi Description: Read-only attribute that exposes the 8-byte unique identifier programmed into the M24LR chip at the factory. Format: - Lowercase hexadecimal string representing a 64-bit value - 1 to 16 hex digits (e.g., "e00204f12345678") - No "0x" prefix - Includes a trailing newline What: /sys/bus/i2c/devices/-/total_sectors Date: 2025-07-04 KernelVersion: 6.17 Contact: Abd-Alrhman Masalkhi Description: Read-only attribute that exposes the total number of EEPROM sectors available in the M24LR chip. Format: - 1 to 2 hex digits (e.g. "F") - No "0x" prefix - Includes a trailing newline Notes: - Value is encoded by the chip and corresponds to the EEPROM size (e.g., 3 = 4 kbit for M24LR04E-R) What: /sys/bus/i2c/devices/-/sss Date: 2025-07-04 KernelVersion: 6.17 Contact: Abd-Alrhman Masalkhi Description: Read/write binary attribute representing the Sector Security Status (SSS) bytes for all EEPROM sectors in STMicroelectronics M24LR chips. Each EEPROM sector has one SSS byte, which controls I2C and RF access through protection bits and optional password authentication. Format: - The file contains one byte per EEPROM sector - Byte at offset N corresponds to sector N - Binary access only; use tools like dd, Python, or C that support byte-level I/O and offset control. Notes: - The number of valid bytes in this file is equal to the value exposed by 'total_sectors' file - Write access requires prior password authentication in I2C mode - Refer to the M24LR datasheet for full SSS bit layout