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authorSalah Triki <salah.triki@gmail.com>2026-09-17 14:00:52 +0100
committerJonathan Cameron <jonathan.cameron@oss.qualcomm.com>2026-09-30 18:59:55 +0100
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iio: proximity: isl29501: Fix return type of isl29501_register_writegrafted
isl29501_register_write() was returning a u32 instead of an int. Since the function returns negative error codes (such as -ERANGE or return values from i2c_smbus_write_byte_data()), returning an unsigned integer type prevents callers from correctly checking for negative error conditions. Fix this by changing the function return type from u32 to int. This was found through manual code review. Fixes: 1c28799257bc ("iio: light: isl29501: Add support for the ISL29501 ToF sensor.") Signed-off-by: Salah Triki <salah.triki@gmail.com> Reviewed-by: Joshua Crofts <joshua.crofts1@gmail.com> Cc: stable@vger.kernel.org Signed-off-by: Jonathan Cameron <jonathan.cameron@oss.qualcomm.com>
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+=========
+dm-linear
+=========
+
+Device-Mapper's "linear" target maps a linear range of the Device-Mapper
+device onto a linear range of another device. This is the basic building
+block of logical volume managers.
+
+Parameters: <dev path> <offset>
+ <dev path>:
+ Full pathname to the underlying block-device, or a
+ "major:minor" device-number.
+ <offset>:
+ Starting sector within the device.
+
+
+Example scripts
+===============
+
+::
+
+ #!/bin/sh
+ # Create an identity mapping for a device
+ echo "0 `blockdev --getsz $1` linear $1 0" | dmsetup create identity
+
+::
+
+ #!/bin/sh
+ # Join 2 devices together
+ size1=`blockdev --getsz $1`
+ size2=`blockdev --getsz $2`
+ echo "0 $size1 linear $1 0
+ $size1 $size2 linear $2 0" | dmsetup create joined
+
+::
+
+ #!/usr/bin/perl -w
+ # Split a device into 4M chunks and then join them together in reverse order.
+
+ my $name = "reverse";
+ my $extent_size = 4 * 1024 * 2;
+ my $dev = $ARGV[0];
+ my $table = "";
+ my $count = 0;
+
+ if (!defined($dev)) {
+ die("Please specify a device.\n");
+ }
+
+ my $dev_size = `blockdev --getsz $dev`;
+ my $extents = int($dev_size / $extent_size) -
+ (($dev_size % $extent_size) ? 1 : 0);
+
+ while ($extents > 0) {
+ my $this_start = $count * $extent_size;
+ $extents--;
+ $count++;
+ my $this_offset = $extents * $extent_size;
+
+ $table .= "$this_start $extent_size linear $dev $this_offset\n";
+ }
+
+ `echo \"$table\" | dmsetup create $name`;