1What: /sys/class/mtd/ 2Date: April 2009 3KernelVersion: 2.6.29 4Contact: [email protected] 5Description: 6 The mtd/ class subdirectory belongs to the MTD subsystem 7 (MTD core). 8 9What: /sys/class/mtd/mtdX/ 10Date: April 2009 11KernelVersion: 2.6.29 12Contact: [email protected] 13Description: 14 The /sys/class/mtd/mtd{0,1,2,3,...} directories correspond 15 to each /dev/mtdX character device. These may represent 16 physical/simulated flash devices, partitions on a flash 17 device, or concatenated flash devices. They exist regardless 18 of whether CONFIG_MTD_CHAR is actually enabled. 19 20What: /sys/class/mtd/mtdXro/ 21Date: April 2009 22KernelVersion: 2.6.29 23Contact: [email protected] 24Description: 25 These directories provide the corresponding read-only device 26 nodes for /sys/class/mtd/mtdX/ . They are only created 27 (for the benefit of udev) if CONFIG_MTD_CHAR is enabled. 28 29What: /sys/class/mtd/mtdX/dev 30Date: April 2009 31KernelVersion: 2.6.29 32Contact: [email protected] 33Description: 34 Major and minor numbers of the character device corresponding 35 to this MTD device (in <major>:<minor> format). This is the 36 read-write device so <minor> will be even. 37 38What: /sys/class/mtd/mtdXro/dev 39Date: April 2009 40KernelVersion: 2.6.29 41Contact: [email protected] 42Description: 43 Major and minor numbers of the character device corresponding 44 to the read-only variant of thie MTD device (in 45 <major>:<minor> format). In this case <minor> will be odd. 46 47What: /sys/class/mtd/mtdX/erasesize 48Date: April 2009 49KernelVersion: 2.6.29 50Contact: [email protected] 51Description: 52 "Major" erase size for the device. If numeraseregions is 53 zero, this is the eraseblock size for the entire device. 54 Otherwise, the MEMGETREGIONCOUNT/MEMGETREGIONINFO ioctls 55 can be used to determine the actual eraseblock layout. 56 57What: /sys/class/mtd/mtdX/flags 58Date: April 2009 59KernelVersion: 2.6.29 60Contact: [email protected] 61Description: 62 A hexadecimal value representing the device flags, ORed 63 together: 64 65 0x0400: MTD_WRITEABLE - device is writable 66 0x0800: MTD_BIT_WRITEABLE - single bits can be flipped 67 0x1000: MTD_NO_ERASE - no erase necessary 68 0x2000: MTD_POWERUP_LOCK - always locked after reset 69 70What: /sys/class/mtd/mtdX/name 71Date: April 2009 72KernelVersion: 2.6.29 73Contact: [email protected] 74Description: 75 A human-readable ASCII name for the device or partition. 76 This will match the name in /proc/mtd . 77 78What: /sys/class/mtd/mtdX/numeraseregions 79Date: April 2009 80KernelVersion: 2.6.29 81Contact: [email protected] 82Description: 83 For devices that have variable eraseblock sizes, this 84 provides the total number of erase regions. Otherwise, 85 it will read back as zero. 86 87What: /sys/class/mtd/mtdX/oobsize 88Date: April 2009 89KernelVersion: 2.6.29 90Contact: [email protected] 91Description: 92 Number of OOB bytes per page. 93 94What: /sys/class/mtd/mtdX/size 95Date: April 2009 96KernelVersion: 2.6.29 97Contact: [email protected] 98Description: 99 Total size of the device/partition, in bytes. 100 101What: /sys/class/mtd/mtdX/type 102Date: April 2009 103KernelVersion: 2.6.29 104Contact: [email protected] 105Description: 106 One of the following ASCII strings, representing the device 107 type: 108 109 absent, ram, rom, nor, nand, dataflash, ubi, unknown 110 111What: /sys/class/mtd/mtdX/writesize 112Date: April 2009 113KernelVersion: 2.6.29 114Contact: [email protected] 115Description: 116 Minimal writable flash unit size. This will always be 117 a positive integer. 118 119 In the case of NOR flash it is 1 (even though individual 120 bits can be cleared). 121 122 In the case of NAND flash it is one NAND page (or a 123 half page, or a quarter page). 124 125 In the case of ECC NOR, it is the ECC block size. 126 127What: /sys/class/mtd/mtdX/ecc_strength 128Date: April 2012 129KernelVersion: 3.4 130Contact: [email protected] 131Description: 132 Maximum number of bit errors that the device is capable of 133 correcting within each region covering an ecc step. This will 134 always be a non-negative integer. Note that some devices will 135 have multiple ecc steps within each writesize region. 136 137 In the case of devices lacking any ECC capability, it is 0. 138