1 What: /sys/bus/nvmem/devices/.../force_ro 2 Date: June 2024 3 KernelVersion: 6.11 4 Contact: Marek Vasut <marex@denx.de> 5 Description: 6 This read/write attribute allows users to set read-write 7 devices as read-only and back to read-write from userspace. 8 This can be used to unlock and relock write-protection of 9 devices which are generally locked, except during sporadic 10 programming operation. 11 Read returns '0' or '1' for read-write or read-only modes 12 respectively. 13 Write parses one of 'YyTt1NnFf0', or [oO][NnFf] for "on" 14 and "off", i.e. what kstrtobool() supports. 15 Note: This file is only present if CONFIG_NVMEM_SYSFS 16 is enabled. 17 18 What: /sys/bus/nvmem/devices/.../nvmem 19 Date: July 2015 20 KernelVersion: 4.2 21 Contact: Srinivas Kandagatla <srinivas.kandagatla@linaro.org> 22 Description: 23 This file allows user to read/write the raw NVMEM contents. 24 Permissions for write to this file depends on the nvmem 25 provider configuration. 26 Note: This file is only present if CONFIG_NVMEM_SYSFS 27 is enabled 28 29 ex:: 30 31 hexdump /sys/bus/nvmem/devices/qfprom0/nvmem 32 33 0000000 0000 0000 0000 0000 0000 0000 0000 0000 34 * 35 00000a0 db10 2240 0000 e000 0c00 0c00 0000 0c00 36 0000000 0000 0000 0000 0000 0000 0000 0000 0000 37 ... 38 * 39 0001000 40 41 What: /sys/bus/nvmem/devices/.../type 42 Date: November 2018 43 KernelVersion: 5.0 44 Contact: Alexandre Belloni <alexandre.belloni@bootlin.com> 45 Description: 46 This read-only attribute allows user to read the NVMEM 47 device type. Supported types are "Unknown", "EEPROM", 48 "OTP", "Battery backed", "FRAM". 49 Note: This file is only present if CONFIG_NVMEM_SYSFS 50 is enabled. 51