19d7eb234SMarek VasutWhat: /sys/bus/nvmem/devices/.../force_ro 29d7eb234SMarek VasutDate: June 2024 39d7eb234SMarek VasutKernelVersion: 6.11 49d7eb234SMarek VasutContact: Marek Vasut <marex@denx.de> 59d7eb234SMarek VasutDescription: 69d7eb234SMarek Vasut This read/write attribute allows users to set read-write 79d7eb234SMarek Vasut devices as read-only and back to read-write from userspace. 89d7eb234SMarek Vasut This can be used to unlock and relock write-protection of 99d7eb234SMarek Vasut devices which are generally locked, except during sporadic 109d7eb234SMarek Vasut programming operation. 119d7eb234SMarek Vasut Read returns '0' or '1' for read-write or read-only modes 129d7eb234SMarek Vasut respectively. 139d7eb234SMarek Vasut Write parses one of 'YyTt1NnFf0', or [oO][NnFf] for "on" 14*3a2de36dSMatthew Wilcox and "off", i.e. what kstrtobool() supports. 159d7eb234SMarek Vasut Note: This file is only present if CONFIG_NVMEM_SYSFS 169d7eb234SMarek Vasut is enabled. 179d7eb234SMarek Vasut 18c26bbb3cSSrinivas KandagatlaWhat: /sys/bus/nvmem/devices/.../nvmem 19c26bbb3cSSrinivas KandagatlaDate: July 2015 20c26bbb3cSSrinivas KandagatlaKernelVersion: 4.2 21c26bbb3cSSrinivas KandagatlaContact: Srinivas Kandagatla <srinivas.kandagatla@linaro.org> 22c26bbb3cSSrinivas KandagatlaDescription: 23c26bbb3cSSrinivas Kandagatla This file allows user to read/write the raw NVMEM contents. 24c26bbb3cSSrinivas Kandagatla Permissions for write to this file depends on the nvmem 25c26bbb3cSSrinivas Kandagatla provider configuration. 26ae0c2d72SSrinivas Kandagatla Note: This file is only present if CONFIG_NVMEM_SYSFS 27ae0c2d72SSrinivas Kandagatla is enabled 28c26bbb3cSSrinivas Kandagatla 2998913408SMauro Carvalho Chehab ex:: 3098913408SMauro Carvalho Chehab 31c26bbb3cSSrinivas Kandagatla hexdump /sys/bus/nvmem/devices/qfprom0/nvmem 32c26bbb3cSSrinivas Kandagatla 33c26bbb3cSSrinivas Kandagatla 0000000 0000 0000 0000 0000 0000 0000 0000 0000 34c26bbb3cSSrinivas Kandagatla * 35c26bbb3cSSrinivas Kandagatla 00000a0 db10 2240 0000 e000 0c00 0c00 0000 0c00 36c26bbb3cSSrinivas Kandagatla 0000000 0000 0000 0000 0000 0000 0000 0000 0000 37c26bbb3cSSrinivas Kandagatla ... 38c26bbb3cSSrinivas Kandagatla * 39c26bbb3cSSrinivas Kandagatla 0001000 40a5f65c77SMarek Vasut 41a5f65c77SMarek VasutWhat: /sys/bus/nvmem/devices/.../type 42a5f65c77SMarek VasutDate: November 2018 43a5f65c77SMarek VasutKernelVersion: 5.0 44a5f65c77SMarek VasutContact: Alexandre Belloni <alexandre.belloni@bootlin.com> 45a5f65c77SMarek VasutDescription: 46a5f65c77SMarek Vasut This read-only attribute allows user to read the NVMEM 47a5f65c77SMarek Vasut device type. Supported types are "Unknown", "EEPROM", 48a5f65c77SMarek Vasut "OTP", "Battery backed", "FRAM". 49a5f65c77SMarek Vasut Note: This file is only present if CONFIG_NVMEM_SYSFS 50a5f65c77SMarek Vasut is enabled. 51