[PATCH 3/7] mtd: expose ecc_strength through sysfs

[Mike Dunn]

ecc_strength element of struct mtd_info is exposed as a read-only variable in
sysfs.  

This patch is unchanged from its earlier version, except for the wording in the
documentation to reflect the fact that it now applies to each ecc step.

Signed-off-by: Mike Dunn <mikedunn at newsguy.com>
---
 Documentation/ABI/testing/sysfs-class-mtd |   12 ++++++++++++
 drivers/mtd/mtdcore.c                     |   10 ++++++++++
 2 files changed, 22 insertions(+), 0 deletions(-)

diff --git a/Documentation/ABI/testing/sysfs-class-mtd b/Documentation/ABI/testing/sysfs-class-mtd
index 4d55a18..43d1818 100644
--- a/Documentation/ABI/testing/sysfs-class-mtd
+++ b/Documentation/ABI/testing/sysfs-class-mtd
@@ -123,3 +123,15 @@ Description:
 		half page, or a quarter page).
 
 		In the case of ECC NOR, it is the ECC block size.
+
+What:		/sys/class/mtd/mtdX/ecc_strength
+Date:		April 2012
+KernelVersion:	3.4
+Contact:	linux-mtd at lists.infradead.org
+Description:
+		Maximum number of bit errors that the device is capable of
+		correcting within each region covering an ecc step.  This will
+		always be a non-negative integer.  Note that some devices will
+		have multiple ecc steps within each writesize region.
+
+		In the case of devices lacking any ECC capability, it is 0.
diff --git a/drivers/mtd/mtdcore.c b/drivers/mtd/mtdcore.c
index c837507..090e849 100644
--- a/drivers/mtd/mtdcore.c
+++ b/drivers/mtd/mtdcore.c
@@ -250,6 +250,15 @@ static ssize_t mtd_name_show(struct device *dev,
 }
 static DEVICE_ATTR(name, S_IRUGO, mtd_name_show, NULL);
 
+static ssize_t mtd_ecc_strength_show(struct device *dev,
+				     struct device_attribute *attr, char *buf)
+{
+	struct mtd_info *mtd = dev_get_drvdata(dev);
+
+	return snprintf(buf, PAGE_SIZE, "%u\n", mtd->ecc_strength);
+}
+static DEVICE_ATTR(ecc_strength, S_IRUGO, mtd_ecc_strength_show, NULL);
+
 static struct attribute *mtd_attrs[] = {
 	&dev_attr_type.attr,
 	&dev_attr_flags.attr,
@@ -260,6 +269,7 @@ static struct attribute *mtd_attrs[] = {
 	&dev_attr_oobsize.attr,
 	&dev_attr_numeraseregions.attr,
 	&dev_attr_name.attr,
+	&dev_attr_ecc_strength.attr,
 	NULL,
 };
 
-- 
1.7.3.4