From: Mike Dunn Date: Tue, 22 May 2012 18:03:42 +0000 (-0700) Subject: mtd: ABI documentation: clarification of bitflip_threshold X-Git-Tag: firefly_0821_release~3680^2~1874^2~171 X-Git-Url: http://demsky.eecs.uci.edu/git/?a=commitdiff_plain;h=021796b892dcad45743f3196e3eef7222870dd55;p=firefly-linux-kernel-4.4.55.git mtd: ABI documentation: clarification of bitflip_threshold The -EUCLEAN return value applies to mtd_read_oob() as well as mtd_read(), but only mtd_read() was mentioned in the blurd on bitflip_threshold in the ABI documentation. Signed-off-by: Mike Dunn Signed-off-by: Artem Bityutskiy Signed-off-by: David Woodhouse --- diff --git a/Documentation/ABI/testing/sysfs-class-mtd b/Documentation/ABI/testing/sysfs-class-mtd index db1ad7e34fc3..938ef71e2035 100644 --- a/Documentation/ABI/testing/sysfs-class-mtd +++ b/Documentation/ABI/testing/sysfs-class-mtd @@ -142,13 +142,14 @@ KernelVersion: 3.4 Contact: linux-mtd@lists.infradead.org Description: This allows the user to examine and adjust the criteria by which - mtd returns -EUCLEAN from mtd_read(). If the maximum number of - bit errors that were corrected on any single region comprising - an ecc step (as reported by the driver) equals or exceeds this - value, -EUCLEAN is returned. Otherwise, absent an error, 0 is - returned. Higher layers (e.g., UBI) use this return code as an - indication that an erase block may be degrading and should be - scrutinized as a candidate for being marked as bad. + mtd returns -EUCLEAN from mtd_read() and mtd_read_oob(). If the + maximum number of bit errors that were corrected on any single + region comprising an ecc step (as reported by the driver) equals + or exceeds this value, -EUCLEAN is returned. Otherwise, absent + an error, 0 is returned. Higher layers (e.g., UBI) use this + return code as an indication that an erase block may be + degrading and should be scrutinized as a candidate for being + marked as bad. The initial value may be specified by the flash device driver. If not, then the default value is ecc_strength. @@ -167,7 +168,7 @@ Description: block degradation, but high enough to avoid the consequences of a persistent return value of -EUCLEAN on devices where sticky bitflips occur. Note that if bitflip_threshold exceeds - ecc_strength, -EUCLEAN is never returned by mtd_read(). + ecc_strength, -EUCLEAN is never returned by the read operations. Conversely, if bitflip_threshold is zero, -EUCLEAN is always returned, absent a hard error.