Merge branch 'next-mtd' of git://aeryn.fluff.org.uk/bjdooks/linux
[linux-2.6] / Documentation / ABI / testing / sysfs-class-mtd
1 What:           /sys/class/mtd/
2 Date:           April 2009
3 KernelVersion:  2.6.29
4 Contact:        linux-mtd@lists.infradead.org
5 Description:
6                 The mtd/ class subdirectory belongs to the MTD subsystem
7                 (MTD core).
8
9 What:           /sys/class/mtd/mtdX/
10 Date:           April 2009
11 KernelVersion:  2.6.29
12 Contact:        linux-mtd@lists.infradead.org
13 Description:
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
20 What:           /sys/class/mtd/mtdXro/
21 Date:           April 2009
22 KernelVersion:  2.6.29
23 Contact:        linux-mtd@lists.infradead.org
24 Description:
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
29 What:           /sys/class/mtd/mtdX/dev
30 Date:           April 2009
31 KernelVersion:  2.6.29
32 Contact:        linux-mtd@lists.infradead.org
33 Description:
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
38 What:           /sys/class/mtd/mtdXro/dev
39 Date:           April 2009
40 KernelVersion:  2.6.29
41 Contact:        linux-mtd@lists.infradead.org
42 Description:
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
47 What:           /sys/class/mtd/mtdX/erasesize
48 Date:           April 2009
49 KernelVersion:  2.6.29
50 Contact:        linux-mtd@lists.infradead.org
51 Description:
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
57 What:           /sys/class/mtd/mtdX/flags
58 Date:           April 2009
59 KernelVersion:  2.6.29
60 Contact:        linux-mtd@lists.infradead.org
61 Description:
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
70 What:           /sys/class/mtd/mtdX/name
71 Date:           April 2009
72 KernelVersion:  2.6.29
73 Contact:        linux-mtd@lists.infradead.org
74 Description:
75                 A human-readable ASCII name for the device or partition.
76                 This will match the name in /proc/mtd .
77
78 What:           /sys/class/mtd/mtdX/numeraseregions
79 Date:           April 2009
80 KernelVersion:  2.6.29
81 Contact:        linux-mtd@lists.infradead.org
82 Description:
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
87 What:           /sys/class/mtd/mtdX/oobsize
88 Date:           April 2009
89 KernelVersion:  2.6.29
90 Contact:        linux-mtd@lists.infradead.org
91 Description:
92                 Number of OOB bytes per page.
93
94 What:           /sys/class/mtd/mtdX/size
95 Date:           April 2009
96 KernelVersion:  2.6.29
97 Contact:        linux-mtd@lists.infradead.org
98 Description:
99                 Total size of the device/partition, in bytes.
100
101 What:           /sys/class/mtd/mtdX/type
102 Date:           April 2009
103 KernelVersion:  2.6.29
104 Contact:        linux-mtd@lists.infradead.org
105 Description:
106                 One of the following ASCII strings, representing the device
107                 type:
108
109                 absent, ram, rom, nor, nand, dataflash, ubi, unknown
110
111 What:           /sys/class/mtd/mtdX/writesize
112 Date:           April 2009
113 KernelVersion:  2.6.29
114 Contact:        linux-mtd@lists.infradead.org
115 Description:
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.