Add support for custom pointer acceleration

Adds new properties and xorg.conf entries for setting the acceleration
function's points and step.

`AccelProfile` option can now accept `custom` value.

Add 4 new options which only apply when `AccelProfile` is `custom`:

- Add `AccelPointsFallback` option for setting the points of the
  Fallback acceleration function. Points values are represented by a
  space-separated list, e.g. "0.0 1.0 2.4 2.5".

- Add `AccelStepFallback` option for setting the step of the Fallback
  acceleration function. When a step of 0.0 is provided,
  libinput default Fallback acceleration function is used.

- Add `AccelPointsMotion` and `AccelStepMotion` options, which are
  equivalent to `AccelPointsFallback` and `AccelStepFallback` options,
  but apply to the Motion acceleration function.

See libinput documentation for a detailed explanation of custom
pointer acceleration.

9 files changed, 1187 insertions, 21 deletions

diff --git a/configure.ac b/configure.ac
index db506ed..3b34b8e 100644
--- a/configure.ac
+++ b/configure.ac
@@ -78,6 +78,17 @@ AC_LINK_IFELSE(
                [AC_MSG_RESULT([no])
                 [libinput_have_axis_value_v120=no]])
 
+AC_MSG_CHECKING([if libinput_config_accel_create is available])
+AC_LINK_IFELSE(
+               [AC_LANG_PROGRAM([[#include <libinput.h>]],
+                                [[libinput_config_accel_create(0)]])],
+               [AC_MSG_RESULT([yes])
+                AC_DEFINE(HAVE_LIBINPUT_CUSTOM_ACCEL, [1],
+                          [libinput_config_accel_create() is available])
+                [libinput_have_custom_accel=yes]],
+               [AC_MSG_RESULT([no])
+                [libinput_have_custom_accel=no]])
+
 LIBS=$OLD_LIBS
 CFLAGS=$OLD_CFLAGS
 
diff --git a/include/libinput-properties.h b/include/libinput-properties.h
index 1655771..004dac9 100644
--- a/include/libinput-properties.h
+++ b/include/libinput-properties.h
@@ -63,18 +63,30 @@
 /* Pointer accel speed: FLOAT, 1 value, 32 bit, read-only*/
 #define LIBINPUT_PROP_ACCEL_DEFAULT "libinput Accel Speed Default"
 
-/* Pointer accel profile: BOOL, 2 values in order adaptive, flat,
+/* Pointer accel profile: BOOL, 3 values in order adaptive, flat, custom
  * only one is enabled at a time at max, read-only */
 #define LIBINPUT_PROP_ACCEL_PROFILES_AVAILABLE "libinput Accel Profiles Available"
 
-/* Pointer accel profile: BOOL, 2 values in order adaptive, flat,
+/* Pointer accel profile: BOOL, 3 values in order adaptive, flat, custom
    only one is enabled at a time at max, read-only */
 #define LIBINPUT_PROP_ACCEL_PROFILE_ENABLED_DEFAULT "libinput Accel Profile Enabled Default"
 
-/* Pointer accel profile: BOOL, 2 values in order adaptive, flat,
+/* Pointer accel profile: BOOL, 3 values in order adaptive, flat, custom
    only one is enabled at a time at max */
 #define LIBINPUT_PROP_ACCEL_PROFILE_ENABLED "libinput Accel Profile Enabled"
 
+/* Points for the custom accel profile: FLOAT, N values */
+#define LIBINPUT_PROP_ACCEL_CUSTOM_POINTS_FALLBACK "libinput Accel Custom Fallback Points"
+
+/* Steps for the custom accel profile: FLOAT, 1 value */
+#define LIBINPUT_PROP_ACCEL_CUSTOM_STEP_FALLBACK "libinput Accel Custom Fallback Step"
+
+/* Points for the custom accel profile: FLOAT, N values */
+#define LIBINPUT_PROP_ACCEL_CUSTOM_POINTS_MOTION "libinput Accel Custom Motion Points"
+
+/* Steps for the custom accel profile: FLOAT, 1 value */
+#define LIBINPUT_PROP_ACCEL_CUSTOM_STEP_MOTION "libinput Accel Custom Motion Step"
+
 /* Natural scrolling: BOOL, 1 value */
 #define LIBINPUT_PROP_NATURAL_SCROLL "libinput Natural Scrolling Enabled"
 
diff --git a/man/libinput.man b/man/libinput.man
index a111da0..689afa4 100644
--- a/man/libinput.man
+++ b/man/libinput.man
@@ -45,13 +45,28 @@ are supported:
 Sets the pointer acceleration profile to the given profile. Permitted values
 are
 .BI adaptive,
-.BI flat.
+.BI flat,
+.BI custom.
 Not all devices support this option or all profiles. If a profile is
 unsupported, the default profile for this device is used. For a description
 on the profiles and their behavior, see the libinput documentation.
 .TP 7
 .BI "Option \*qAccelSpeed\*q \*q" float \*q
-Sets the pointer acceleration speed within the range [-1, 1]
+Sets the pointer acceleration speed within the range [-1, 1].
+This only applies to the flat or adaptive profile.
+.BI "Option \*AccelPointsFallback\*q \*q" string \*q
+Sets the points of the Fallback acceleration function, (see the libinput documentation).
+The string must be a space-separated list of floating point non-negative numbers, e.g.
+"0.0 1.0 2.4 2.5".
+This only applies to the custom profile.
+.BI "Option \*AccelStepFallback\*q \*q" float \*q
+Sets the step between the points of the Fallback acceleration function, (see the libinput documentation).
+When a step of 0.0 is provided, libinput's default Fallback acceleration function is used.
+This only applies to the custom profile.
+.BI "Option \*AccelPointsMotion\*q \*q" string \*q
+Equivalent to AccelPointsFallback but applies to the Motion acceleration function.
+.BI "Option \*AccelStepMotion\*q \*q" float \*q
+Equivalent to AccelStepFallback but applies to the Motion acceleration function.
 .TP 7
 .BI "Option \*qButtonMapping\*q \*q" string \*q
 Sets the logical button mapping for this device, see
diff --git a/meson.build b/meson.build
index 2a5a639..cb0926f 100644
--- a/meson.build
+++ b/meson.build
@@ -53,6 +53,10 @@ if cc.has_function('libinput_event_pointer_get_scroll_value_v120',
 	           dependencies: dep_libinput)
 	config_h.set('HAVE_LIBINPUT_AXIS_VALUE_V120', 1)
 endif
+if cc.has_function('libinput_config_accel_create',
+		   dependencies: dep_libinput)
+	config_h.set('HAVE_LIBINPUT_CUSTOM_ACCEL', 1)
+endif
 
 dir_headers = get_option('sdkdir')
 if dir_headers == ''
@@ -84,7 +88,7 @@ dep_drivers = [
   dep_libdraglock,
 ]
 
-driver_src = ['src/xf86libinput.c']
+driver_src = ['src/xf86libinput.c', 'src/util-strings.c']
 driver_lib = shared_module(
 	'libinput_drv',
 	driver_src,
diff --git a/src/Makefile.am b/src/Makefile.am
index 5dcb55e..44d3a9c 100644
--- a/src/Makefile.am
+++ b/src/Makefile.am
@@ -33,7 +33,12 @@ AM_CPPFLAGS =-I$(top_srcdir)/include $(LIBINPUT_CFLAGS)
 @DRIVER_NAME@_drv_la_LIBADD = $(LIBINPUT_LIBS) libdraglock.la libbezier.la -lm
 @DRIVER_NAME@_drv_ladir = @inputdir@
 
-@DRIVER_NAME@_drv_la_SOURCES = xf86libinput.c
+@DRIVER_NAME@_drv_la_SOURCES = \
+	xf86libinput.c \
+	util-macros.h \
+	util-strings.h \
+	util-strings.c \
+	$(NULL)
 
 noinst_LTLIBRARIES = libdraglock.la libbezier.la
 libdraglock_la_SOURCES = draglock.c draglock.h
diff --git a/src/util-macros.h b/src/util-macros.h
new file mode 100644
index 0000000..d56a8a3
--- /dev/null
+++ b/src/util-macros.h
@@ -0,0 +1,65 @@
+/*
+ * Copyright © 2008-2011 Kristian Høgsberg
+ * Copyright © 2011 Intel Corporation
+ * Copyright © 2013-2015 Red Hat, Inc.
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a
+ * copy of this software and associated documentation files (the "Software"),
+ * to deal in the Software without restriction, including without limitation
+ * the rights to use, copy, modify, merge, publish, distribute, sublicense,
+ * and/or sell copies of the Software, and to permit persons to whom the
+ * Software is furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice (including the next
+ * paragraph) shall be included in all copies or substantial portions of the
+ * Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
+ * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
+ * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
+ * DEALINGS IN THE SOFTWARE.
+ */
+
+#pragma once
+
+#include "config.h"
+
+#define ARRAY_LENGTH(a) (sizeof (a) / sizeof (a)[0])
+/**
+ * Iterate through the array _arr, assigning the variable elem to each
+ * element. elem only exists within the loop.
+ */
+#define ARRAY_FOR_EACH(_arr, _elem) \
+	for (__typeof__((_arr)[0]) *_elem = _arr; \
+	     _elem < (_arr) + ARRAY_LENGTH(_arr); \
+	     _elem++)
+
+#define min(a, b) (((a) < (b)) ? (a) : (b))
+#define max(a, b) (((a) > (b)) ? (a) : (b))
+
+#define ANSI_HIGHLIGHT		"\x1B[0;1;39m"
+#define ANSI_RED		"\x1B[0;31m"
+#define ANSI_GREEN		"\x1B[0;32m"
+#define ANSI_YELLOW		"\x1B[0;33m"
+#define ANSI_BLUE		"\x1B[0;34m"
+#define ANSI_MAGENTA		"\x1B[0;35m"
+#define ANSI_CYAN		"\x1B[0;36m"
+#define ANSI_BRIGHT_RED		"\x1B[0;31;1m"
+#define ANSI_BRIGHT_GREEN	"\x1B[0;32;1m"
+#define ANSI_BRIGHT_YELLOW	"\x1B[0;33;1m"
+#define ANSI_BRIGHT_BLUE	"\x1B[0;34;1m"
+#define ANSI_BRIGHT_MAGENTA	"\x1B[0;35;1m"
+#define ANSI_BRIGHT_CYAN	"\x1B[0;36;1m"
+#define ANSI_NORMAL		"\x1B[0m"
+
+#define ANSI_UP			"\x1B[%dA"
+#define ANSI_DOWN		"\x1B[%dB"
+#define ANSI_RIGHT		"\x1B[%dC"
+#define ANSI_LEFT		"\x1B[%dD"
+
+#define CASE_RETURN_STRING(a) case a: return #a
+
+#define _fallthrough_ __attribute__((fallthrough))
diff --git a/src/util-strings.c b/src/util-strings.c
new file mode 100644
index 0000000..d0a3fa0
--- /dev/null
+++ b/src/util-strings.c
@@ -0,0 +1,243 @@
+/*
+ * Copyright © 2008 Kristian Høgsberg
+ * Copyright © 2013-2015 Red Hat, Inc.
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a
+ * copy of this software and associated documentation files (the "Software"),
+ * to deal in the Software without restriction, including without limitation
+ * the rights to use, copy, modify, merge, publish, distribute, sublicense,
+ * and/or sell copies of the Software, and to permit persons to whom the
+ * Software is furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice (including the next
+ * paragraph) shall be included in all copies or substantial portions of the
+ * Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
+ * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
+ * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
+ * DEALINGS IN THE SOFTWARE.
+ */
+
+#include "config.h"
+
+#include "util-strings.h"
+
+/**
+ * Return the next word in a string pointed to by state before the first
+ * separator character. Call repeatedly to tokenize a whole string.
+ *
+ * @param state Current state
+ * @param len String length of the word returned
+ * @param separators List of separator characters
+ *
+ * @return The first word in *state, NOT null-terminated
+ */
+static const char *
+next_word(const char **state, size_t *len, const char *separators)
+{
+	const char *next = *state;
+	size_t l;
+
+	if (!*next)
+		return NULL;
+
+	next += strspn(next, separators);
+	if (!*next) {
+		*state = next;
+		return NULL;
+	}
+
+	l = strcspn(next, separators);
+	*state = next + l;
+	*len = l;
+
+	return next;
+}
+
+/**
+ * Return a null-terminated string array with the contents of argv
+ * duplicated.
+ *
+ * Use strv_free() to free the array.
+ *
+ * @return A null-terminated string array or NULL on errors
+ */
+char**
+strv_from_argv(int argc, char **argv)
+{
+	char **strv = NULL;
+
+	assert(argc >= 0);
+
+	if (argc == 0)
+		return NULL;
+
+	strv = zalloc((argc + 1) * sizeof *strv);
+	for (int i = 0; i < argc; i++) {
+		char *copy = safe_strdup(argv[i]);
+		if (!copy) {
+			strv_free(strv);
+			return NULL;
+		}
+		strv[i] = copy;
+	}
+	return strv;
+}
+
+/**
+ * Return a null-terminated string array with the tokens in the input
+ * string, e.g. "one two\tthree" with a separator list of " \t" will return
+ * an array [ "one", "two", "three", NULL ] and num elements 3.
+ *
+ * Use strv_free() to free the array.
+ *
+ * Another example:
+ *   result = strv_from_string("+1-2++3--4++-+5-+-", "+-", &nelem)
+ *   result == [ "1", "2", "3", "4", "5", NULL ] and nelem == 5
+ *
+ * @param in Input string
+ * @param separators List of separator characters
+ * @param num_elements Number of elements found in the input string
+ *
+ * @return A null-terminated string array or NULL on errors
+ */
+char **
+strv_from_string(const char *in, const char *separators, size_t *num_elements)
+{
+	assert(in != NULL);
+
+	const char *s = in;
+	size_t l, nelems = 0;
+	while (next_word(&s, &l, separators) != NULL)
+		nelems++;
+
+	if (nelems == 0) {
+		*num_elements = 0;
+		return NULL;
+	}
+
+	size_t strv_len = nelems + 1; /* NULL-terminated */
+	char **strv = zalloc(strv_len * sizeof *strv);
+
+	size_t idx = 0;
+	const char *word;
+	s = in;
+	while ((word = next_word(&s, &l, separators)) != NULL) {
+		char *copy = strndup(word, l);
+		if (!copy) {
+			strv_free(strv);
+			*num_elements = 0;
+			return NULL;
+		}
+
+		strv[idx++] = copy;
+	}
+
+	*num_elements = nelems;
+
+	return strv;
+}
+
+/**
+ * Return a newly allocated string with all elements joined by the
+ * joiner, same as Python's string.join() basically.
+ * A strv of ["one", "two", "three", NULL] with a joiner of ", " results
+ * in "one, two, three".
+ *
+ * An empty strv ([NULL]) returns NULL, same for passing NULL as either
+ * argument.
+ *
+ * @param strv Input string array
+ * @param joiner Joiner between the elements in the final string
+ *
+ * @return A null-terminated string joining all elements
+ */
+char *
+strv_join(char **strv, const char *joiner)
+{
+	char **s;
+	char *str;
+	size_t slen = 0;
+	size_t count = 0;
+
+	if (!strv || !joiner)
+		return NULL;
+
+	if (strv[0] == NULL)
+		return NULL;
+
+	for (s = strv, count = 0; *s; s++, count++) {
+		slen += strlen(*s);
+	}
+
+	assert(slen < 1000);
+	assert(strlen(joiner) < 1000);
+	assert(count > 0);
+	assert(count < 100);
+
+	slen += (count - 1) * strlen(joiner);
+
+	str = zalloc(slen + 1); /* trailing \0 */
+	for (s = strv; *s; s++) {
+		strcat(str, *s);
+		--count;
+		if (count > 0)
+			strcat(str, joiner);
+	}
+
+	return str;
+}
+
+/**
+ * Return a pointer to the basename within filename.
+ * If the filename the empty string or a directory (i.e. the last char of
+ * filename is '/') NULL is returned.
+ */
+const char *
+safe_basename(const char *filename)
+{
+	const char *basename;
+
+	if (*filename == '\0')
+		return NULL;
+
+	basename = strrchr(filename, '/');
+	if (basename == NULL)
+		return filename;
+
+	if (*(basename + 1) == '\0')
+		return NULL;
+
+	return basename + 1;
+}
+
+/**
+ * Similar to basename() but returns the trunk only without the (last)
+ * trailing suffix, so that:
+ *
+ * - foo.c returns foo
+ * - foo.a.b returns foo.a
+ * - foo returns foo
+ * - foo/ returns ""
+ *
+ * @return an allocated string representing the trunk name of the file
+ */
+char *
+trunkname(const char *filename)
+{
+	const char *base = safe_basename(filename);
+	char *suffix;
+
+	if (base == NULL)
+		return safe_strdup("");
+
+	suffix = rindex(base, '.');
+	if (suffix == NULL)
+		return safe_strdup(base);
+	else
+		return strndup(base, suffix-base);
+}
diff --git a/src/util-strings.h b/src/util-strings.h
new file mode 100644
index 0000000..dc68beb
--- /dev/null
+++ b/src/util-strings.h
@@ -0,0 +1,464 @@
+/*
+ * Copyright © 2008 Kristian Høgsberg
+ * Copyright © 2013-2015 Red Hat, Inc.
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a
+ * copy of this software and associated documentation files (the "Software"),
+ * to deal in the Software without restriction, including without limitation
+ * the rights to use, copy, modify, merge, publish, distribute, sublicense,
+ * and/or sell copies of the Software, and to permit persons to whom the
+ * Software is furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice (including the next
+ * paragraph) shall be included in all copies or substantial portions of the
+ * Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
+ * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
+ * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
+ * DEALINGS IN THE SOFTWARE.
+ */
+
+#pragma once
+
+#include "config.h"
+#define _GNU_SOURCE
+
+#include <assert.h>
+#include <ctype.h>
+#include <errno.h>
+#include <limits.h>
+#include <math.h>
+#include <string.h>
+#include <stdio.h>
+#include <stdbool.h>
+#include <stdlib.h>
+#include <stdarg.h>
+#ifdef HAVE_LOCALE_H
+#include <locale.h>
+#endif
+#ifdef HAVE_XLOCALE_H
+#include <xlocale.h>
+#endif
+
+#include "util-macros.h"
+
+static inline bool
+streq(const char *str1, const char *str2)
+{
+	/* one NULL, one not NULL is always false */
+	if (str1 && str2)
+		return strcmp(str1, str2) == 0;
+	return str1 == str2;
+}
+
+static inline bool
+strneq(const char *str1, const char *str2, int n)
+{
+	/* one NULL, one not NULL is always false */
+	if (str1 && str2)
+		return strncmp(str1, str2, n) == 0;
+	return str1 == str2;
+}
+
+static inline void *
+zalloc(size_t size)
+{
+	void *p;
+
+	/* We never need to alloc anything more than 1,5 MB so we can assume
+	 * if we ever get above that something's going wrong */
+	if (size > 1536 * 1024)
+		assert(!"bug: internal malloc size limit exceeded");
+
+	p = calloc(1, size);
+	if (!p)
+		abort();
+
+	return p;
+}
+
+/**
+ * strdup guaranteed to succeed. If the input string is NULL, the output
+ * string is NULL. If the input string is a string pointer, we strdup or
+ * abort on failure.
+ */
+static inline char*
+safe_strdup(const char *str)
+{
+	char *s;
+
+	if (!str)
+		return NULL;
+
+	s = strdup(str);
+	if (!s)
+		abort();
+	return s;
+}
+
+/**
+ * Simple wrapper for asprintf that ensures the passed in-pointer is set
+ * to NULL upon error.
+ * The standard asprintf() call does not guarantee the passed in pointer
+ * will be NULL'ed upon failure, whereas this wrapper does.
+ *
+ * @param strp pointer to set to newly allocated string.
+ * This pointer should be passed to free() to release when done.
+ * @param fmt the format string to use for printing.
+ * @return The number of bytes printed (excluding the null byte terminator)
+ * upon success or -1 upon failure. In the case of failure the pointer is set
+ * to NULL.
+ */
+__attribute__ ((format (printf, 2, 3)))
+static inline int
+xasprintf(char **strp, const char *fmt, ...)
+{
+	int rc = 0;
+	va_list args;
+
+	va_start(args, fmt);
+	rc = vasprintf(strp, fmt, args);
+	va_end(args);
+	if ((rc == -1) && strp)
+		*strp = NULL;
+
+	return rc;
+}
+
+__attribute__ ((format (printf, 2, 0)))
+static inline int
+xvasprintf(char **strp, const char *fmt, va_list args)
+{
+	int rc = 0;
+	rc = vasprintf(strp, fmt, args);
+	if ((rc == -1) && strp)
+		*strp = NULL;
+
+	return rc;
+}
+
+static inline bool
+safe_atoi_base(const char *str, int *val, int base)
+{
+	char *endptr;
+	long v;
+
+	assert(base == 10 || base == 16 || base == 8);
+
+	errno = 0;
+	v = strtol(str, &endptr, base);
+	if (errno > 0)
+		return false;
+	if (str == endptr)
+		return false;
+	if (*str != '\0' && *endptr != '\0')
+		return false;
+
+	if (v > INT_MAX || v < INT_MIN)
+		return false;
+
+	*val = v;
+	return true;
+}
+
+static inline bool
+safe_atoi(const char *str, int *val)
+{
+	return safe_atoi_base(str, val, 10);
+}
+
+static inline bool
+safe_atou_base(const char *str, unsigned int *val, int base)
+{
+	char *endptr;
+	unsigned long v;
+
+	assert(base == 10 || base == 16 || base == 8);
+
+	errno = 0;
+	v = strtoul(str, &endptr, base);
+	if (errno > 0)
+		return false;
+	if (str == endptr)
+		return false;
+	if (*str != '\0' && *endptr != '\0')
+		return false;
+
+	if ((long)v < 0)
+		return false;
+
+	*val = v;
+	return true;
+}
+
+static inline bool
+safe_atou(const char *str, unsigned int *val)
+{
+	return safe_atou_base(str, val, 10);
+}
+
+static inline bool
+safe_atod(const char *str, double *val)
+{
+	char *endptr;
+	double v;
+#ifdef HAVE_LOCALE_H
+	locale_t c_locale;
+#endif
+	size_t slen = strlen(str);
+
+	/* We don't have a use-case where we want to accept hex for a double
+	 * or any of the other values strtod can parse */
+	for (size_t i = 0; i < slen; i++) {
+		char c = str[i];
+
+		if (isdigit(c))
+		       continue;
+		switch(c) {
+		case '+':
+		case '-':
+		case '.':
+			break;
+		default:
+			return false;
+		}
+	}
+
+#ifdef HAVE_LOCALE_H
+	/* Create a "C" locale to force strtod to use '.' as separator */
+	c_locale = newlocale(LC_NUMERIC_MASK, "C", (locale_t)0);
+	if (c_locale == (locale_t)0)
+		return false;
+
+	errno = 0;
+	v = strtod_l(str, &endptr, c_locale);
+	freelocale(c_locale);
+#else
+	/* No locale support in provided libc, assume it already uses '.' */
+	errno = 0;
+	v = strtod(str, &endptr);
+#endif
+	if (errno > 0)
+		return false;
+	if (str == endptr)
+		return false;
+	if (*str != '\0' && *endptr != '\0')
+		return false;
+	if (v != 0.0 && !isnormal(v))
+		return false;
+
+	*val = v;
+	return true;
+}
+
+char **strv_from_argv(int argc, char **argv);
+char **strv_from_string(const char *in, const char *separator, size_t *num_elements);
+char *strv_join(char **strv, const char *joiner);
+
+static inline void
+strv_free(char **strv) {
+	char **s = strv;
+
+	if (!strv)
+		return;
+
+	while (*s != NULL) {
+		free(*s);
+		*s = (char*)0x1; /* detect use-after-free */
+		s++;
+	}
+
+	free (strv);
+}
+
+/**
+ * parse a string containing a list of doubles into a double array.
+ *
+ * @param in string to parse
+ * @param separator string used to separate double in list e.g. ","
+ * @param result double array
+ * @param length length of double array
+ * @return true when parsed successfully otherwise false
+ */
+static inline double *
+double_array_from_string(const char *in,
+			 const char *separator,
+			 size_t *length)
+{
+	double *result = NULL;
+	*length = 0;
+
+	size_t nelem;
+	char **strv = strv_from_string(in, separator, &nelem);
+	if(!strv)
+		return result;
+
+	double *numv = zalloc(sizeof(double) * nelem);
+	for (size_t idx = 0; idx < nelem; idx++) {
+		double val;
+		if (!safe_atod(strv[idx], &val))
+			goto out;
+
+		numv[idx] = val;
+	}
+
+	result = numv;
+	numv = NULL;
+	*length = nelem;
+
+out:
+	strv_free(strv);
+	free(numv);
+	return result;
+}
+
+struct key_value_str{
+	char *key;
+	char *value;
+};
+
+struct key_value_double {
+	double key;
+	double value;
+};
+
+static inline ssize_t
+kv_double_from_string(const char *string,
+		      const char *pair_separator,
+		      const char *kv_separator,
+		      struct key_value_double **result_out)
+
+{
+	struct key_value_double *result = NULL;
+
+	if (!pair_separator || pair_separator[0] == '\0' ||
+	    !kv_separator || kv_separator[0] == '\0')
+		return -1;
+
+	size_t npairs;
+	char **pairs = strv_from_string(string, pair_separator, &npairs);
+	if (!pairs || npairs == 0)
+		goto error;
+
+	result = zalloc(npairs * sizeof *result);
+
+	for (size_t idx = 0; idx < npairs; idx++) {
+		char *pair = pairs[idx];
+		size_t nelem;
+		char **kv = strv_from_string(pair, kv_separator, &nelem);
+		double k, v;
+
+		if (!kv || nelem != 2 ||
+		    !safe_atod(kv[0], &k) ||
+		    !safe_atod(kv[1], &v)) {
+			strv_free(kv);
+			goto error;
+		}
+
+		result[idx].key = k;
+		result[idx].value = v;
+
+		strv_free(kv);
+	}
+
+	strv_free(pairs);
+
+	*result_out = result;
+
+	return npairs;
+
+error:
+	strv_free(pairs);
+	free(result);
+	return -1;
+}
+
+/**
+ * Strip any of the characters in what from the beginning and end of the
+ * input string.
+ *
+ * @return a newly allocated string with none of "what" at the beginning or
+ * end of string
+ */
+static inline char *
+strstrip(const char *input, const char *what)
+{
+	char *str, *last;
+
+	str = safe_strdup(&input[strspn(input, what)]);
+
+	last = str;
+
+	for (char *c = str; *c != '\0'; c++) {
+		if (!strchr(what, *c))
+			last = c + 1;
+	}
+
+	*last = '\0';
+
+	return str;
+}
+
+/**
+ * Return true if str ends in suffix, false otherwise. If the suffix is the
+ * empty string, strendswith() always returns false.
+ */
+static inline bool
+strendswith(const char *str, const char *suffix)
+{
+	size_t slen = strlen(str);
+	size_t suffixlen = strlen(suffix);
+	size_t offset;
+
+	if (slen == 0 || suffixlen == 0 || suffixlen > slen)
+		return false;
+
+	offset = slen - suffixlen;
+	return strneq(&str[offset], suffix, suffixlen);
+}
+
+static inline bool
+strstartswith(const char *str, const char *prefix)
+{
+	size_t prefixlen = strlen(prefix);
+
+	return prefixlen > 0 ? strneq(str, prefix, strlen(prefix)) : false;
+}
+
+const char *
+safe_basename(const char *filename);
+
+char *
+trunkname(const char *filename);
+
+/**
+ * Return a copy of str with all % converted to %% to make the string
+ * acceptable as printf format.
+ */
+static inline char *
+str_sanitize(const char *str)
+{
+	if (!str)
+		return NULL;
+
+	if (!strchr(str, '%'))
+		return strdup(str);
+
+	size_t slen = min(strlen(str), 512);
+	char *sanitized = zalloc(2 * slen + 1);
+	const char *src = str;
+	char *dst = sanitized;
+
+	for (size_t i = 0; i < slen; i++) {
+		if (*src == '%')
+			*dst++ = '%';
+		*dst++ = *src++;
+	}
+	*dst = '\0';
+
+	return sanitized;
+}
diff --git a/src/xf86libinput.c b/src/xf86libinput.c
index 92e567d..fbe1e94 100644
--- a/src/xf86libinput.c
+++ b/src/xf86libinput.c
@@ -45,6 +45,7 @@
 #include "bezier.h"
 #include "draglock.h"
 #include "libinput-properties.h"
+#include "util-strings.h"
 
 #define TOUCHPAD_NUM_AXES 4 /* x, y, hscroll, vscroll */
 #define TABLET_NUM_BUTTONS 7 /* we need scroll buttons */
@@ -54,6 +55,15 @@
 #define TOUCHPAD_SCROLL_DIST_MIN 10 /* in libinput pixels */
 #define TOUCHPAD_SCROLL_DIST_MAX 50 /* in libinput pixels */
 
+#if HAVE_LIBINPUT_CUSTOM_ACCEL
+#define CUSTOM_ACCEL_NPOINTS_MIN 2
+#define CUSTOM_ACCEL_NPOINTS_MAX 64
+#define CUSTOM_ACCEL_POINT_MIN 0
+#define CUSTOM_ACCEL_POINT_MAX 10000
+#define CUSTOM_ACCEL_STEP_MIN 0
+#define CUSTOM_ACCEL_STEP_MAX 10000
+#endif
+
 #define streq(a, b) (strcmp(a, b) == 0)
 #define strneq(a, b, n) (strncmp(a, b, n) == 0)
 
@@ -118,6 +128,14 @@ struct xf86libinput_tablet_tool {
 	struct libinput_tablet_tool *tool;
 };
 
+#if HAVE_LIBINPUT_CUSTOM_ACCEL
+struct accel_points {
+	double step;
+	double points[CUSTOM_ACCEL_NPOINTS_MAX];
+	size_t npoints;
+};
+#endif
+
 struct xf86libinput {
 	InputInfoPtr pInfo;
 	char *path;
@@ -160,7 +178,10 @@ struct xf86libinput {
 		enum libinput_config_scroll_method scroll_method;
 		enum libinput_config_click_method click_method;
 		enum libinput_config_accel_profile accel_profile;
-
+#if HAVE_LIBINPUT_CUSTOM_ACCEL
+		struct accel_points accel_points_fallback;
+		struct accel_points accel_points_motion;
+#endif
 		unsigned char btnmap[MAX_BUTTONS + 1];
 
 		BOOL horiz_scrolling_enabled;
@@ -514,11 +535,57 @@ LibinputApplyConfigNaturalScroll(DeviceIntPtr dev,
 			    driver_data->options.natural_scrolling);
 }
 
+#if HAVE_LIBINPUT_CUSTOM_ACCEL
+static bool
+LibinputApplyConfigAccelCustom(struct xf86libinput *driver_data,
+			       struct libinput_device *device)
+{
+	bool success = false;
+	struct libinput_config_accel *accel;
+	enum libinput_config_status status;
+
+	accel = libinput_config_accel_create(LIBINPUT_CONFIG_ACCEL_PROFILE_CUSTOM);
+	if (!accel)
+		goto out;
+
+	/* If the step is 0, the user has not set a custom function,
+	   thus we don't set the points */
+	if (driver_data->options.accel_points_fallback.step > 0 &&
+	    driver_data->options.accel_points_fallback.npoints >= 2) {
+		status = libinput_config_accel_set_points(accel,
+							  LIBINPUT_ACCEL_TYPE_FALLBACK,
+							  driver_data->options.accel_points_fallback.step,
+							  driver_data->options.accel_points_fallback.npoints,
+							  driver_data->options.accel_points_fallback.points);
+		if (status != LIBINPUT_CONFIG_STATUS_SUCCESS)
+			goto out;
+	}
+
+	if (driver_data->options.accel_points_motion.step > 0 &&
+	    driver_data->options.accel_points_motion.npoints >= 2) {
+		status = libinput_config_accel_set_points(accel,
+							  LIBINPUT_ACCEL_TYPE_MOTION,
+							  driver_data->options.accel_points_motion.step,
+							  driver_data->options.accel_points_motion.npoints,
+							  driver_data->options.accel_points_motion.points);
+		if (status != LIBINPUT_CONFIG_STATUS_SUCCESS)
+			goto out;
+	}
+
+	status = libinput_device_config_accel_apply(device, accel);
+	success = status == LIBINPUT_CONFIG_STATUS_SUCCESS;
+out:
+	libinput_config_accel_destroy(accel);
+	return success;
+}
+#endif
+
 static void
 LibinputApplyConfigAccel(DeviceIntPtr dev,
 			 struct xf86libinput *driver_data,
 			 struct libinput_device *device)
 {
+	bool success = false;
 	InputInfoPtr pInfo = dev->public.devicePrivate;
 
 	if (!subdevice_has_capabilities(dev, CAP_POINTER))
@@ -527,15 +594,31 @@ LibinputApplyConfigAccel(DeviceIntPtr dev,
 	if (libinput_device_config_accel_is_available(device) &&
 	    libinput_device_config_accel_set_speed(device,
 						   driver_data->options.speed) != LIBINPUT_CONFIG_STATUS_SUCCESS)
-			xf86IDrvMsg(pInfo, X_ERROR,
-				    "Failed to set speed %.2f\n",
-				    driver_data->options.speed);
-
-	if (libinput_device_config_accel_get_profiles(device) &&
-	    driver_data->options.accel_profile != LIBINPUT_CONFIG_ACCEL_PROFILE_NONE  &&
-	    libinput_device_config_accel_set_profile(device,
-						     driver_data->options.accel_profile) !=
-			    LIBINPUT_CONFIG_STATUS_SUCCESS) {
+		xf86IDrvMsg(pInfo, X_ERROR,
+			    "Failed to set speed %.2f\n",
+			    driver_data->options.speed);
+
+	if (!libinput_device_config_accel_get_profiles(device) ||
+	    driver_data->options.accel_profile == LIBINPUT_CONFIG_ACCEL_PROFILE_NONE)
+		return;
+
+	switch (driver_data->options.accel_profile) {
+	case LIBINPUT_CONFIG_ACCEL_PROFILE_FLAT:
+	case LIBINPUT_CONFIG_ACCEL_PROFILE_ADAPTIVE:
+		success = libinput_device_config_accel_set_profile(device, driver_data->options.accel_profile) ==
+				LIBINPUT_CONFIG_STATUS_SUCCESS;
+		break;
+#if HAVE_LIBINPUT_CUSTOM_ACCEL
+	case LIBINPUT_CONFIG_ACCEL_PROFILE_CUSTOM:
+		success = LibinputApplyConfigAccelCustom(driver_data, device);
+		break;
+#endif
+	default:
+		success = false;
+		break;
+	}
+
+	if (!success) {
 		const char *profile;
 
 		switch (driver_data->options.accel_profile) {
@@ -545,6 +628,11 @@ LibinputApplyConfigAccel(DeviceIntPtr dev,
 		case LIBINPUT_CONFIG_ACCEL_PROFILE_FLAT:
 			profile = "flat";
 			break;
+#if HAVE_LIBINPUT_CUSTOM_ACCEL
+		case LIBINPUT_CONFIG_ACCEL_PROFILE_CUSTOM:
+			profile = "custom";
+			break;
+#endif
 		default:
 			profile = "unknown";
 			break;
@@ -2815,10 +2903,14 @@ xf86libinput_parse_accel_profile_option(InputInfoPtr pInfo,
 	str = xf86SetStrOption(pInfo->options, "AccelProfile", NULL);
 	if (!str)
 		profile = libinput_device_config_accel_get_profile(device);
-	else if (strncasecmp(str, "adaptive", 9) == 0)
+	else if (strcasecmp(str, "adaptive") == 0)
 		profile = LIBINPUT_CONFIG_ACCEL_PROFILE_ADAPTIVE;
-	else if (strncasecmp(str, "flat", 4) == 0)
+	else if (strcasecmp(str, "flat") == 0)
 		profile = LIBINPUT_CONFIG_ACCEL_PROFILE_FLAT;
+#if HAVE_LIBINPUT_CUSTOM_ACCEL
+	else if (strcasecmp(str, "custom") == 0)
+		profile = LIBINPUT_CONFIG_ACCEL_PROFILE_CUSTOM;
+#endif
 	else {
 		xf86IDrvMsg(pInfo, X_ERROR,
 			    "Unknown accel profile '%s'. Using default.\n",
@@ -2831,6 +2923,106 @@ xf86libinput_parse_accel_profile_option(InputInfoPtr pInfo,
 	return profile;
 }
 
+#if HAVE_LIBINPUT_CUSTOM_ACCEL
+static inline struct accel_points
+xf86libinput_parse_accel_points_option(InputInfoPtr pInfo, struct libinput_device *device, const char *name)
+{
+	struct accel_points accel_points = {0};
+	char *str = NULL;
+	double *points = NULL;
+	size_t npoints = 0;
+
+	if ((libinput_device_config_accel_get_profiles(device) & LIBINPUT_CONFIG_ACCEL_PROFILE_CUSTOM) == 0)
+		goto out;
+
+	str = xf86SetStrOption(pInfo->options, name, NULL);
+	if (!str)
+		goto out;
+
+	points = double_array_from_string(str, " ", &npoints);
+	if (!points) {
+		xf86IDrvMsg(pInfo, X_ERROR, "Failed to parse AccelPoints, ignoring points.\n");
+		goto out;
+	}
+
+	if (npoints < CUSTOM_ACCEL_NPOINTS_MIN) {
+		xf86IDrvMsg(pInfo, X_ERROR, "At least %d AccelPoints are required, ignoring points.\n",
+			    CUSTOM_ACCEL_NPOINTS_MIN);
+		goto out;
+	}
+
+	if (npoints > CUSTOM_ACCEL_NPOINTS_MAX) {
+		xf86IDrvMsg(pInfo, X_WARNING, "Excessive number of AccelPoints, clipping to first %d points.\n",
+			    CUSTOM_ACCEL_NPOINTS_MAX);
+		npoints = CUSTOM_ACCEL_NPOINTS_MAX;
+	}
+
+	for (size_t idx = 0; idx < npoints; idx++) {
+		if (points[idx] < CUSTOM_ACCEL_POINT_MIN || points[idx] > CUSTOM_ACCEL_POINT_MAX) {
+			xf86IDrvMsg(pInfo, X_ERROR, "AccelPoints are not in the allowed range between %d and %d, ignoring points.\n",
+				    CUSTOM_ACCEL_POINT_MIN,
+				    CUSTOM_ACCEL_POINT_MAX);
+			goto out;
+		}
+	}
+
+	memcpy(accel_points.points, points, npoints * sizeof(*points));
+	accel_points.npoints = npoints;
+
+out:
+	free(str);
+	free(points);
+	return accel_points;
+}
+
+static inline struct accel_points
+xf86libinput_parse_accel_points_fallback_option(InputInfoPtr pInfo, struct libinput_device *device)
+{
+	return xf86libinput_parse_accel_points_option(pInfo, device, "AccelPointsFallback");
+}
+
+static inline struct accel_points
+xf86libinput_parse_accel_points_motion_option(InputInfoPtr pInfo, struct libinput_device *device)
+{
+	return xf86libinput_parse_accel_points_option(pInfo, device, "AccelPointsMotion");
+}
+
+static inline double
+xf86libinput_parse_accel_step_option(InputInfoPtr pInfo, struct libinput_device *device, const char *name)
+{
+	double step = 0.0;
+	double parsed_step;
+
+	if ((libinput_device_config_accel_get_profiles(device) & LIBINPUT_CONFIG_ACCEL_PROFILE_CUSTOM) == 0)
+		return step;
+
+	parsed_step = xf86SetRealOption(pInfo->options, name, 0.0);
+
+	if (parsed_step < CUSTOM_ACCEL_STEP_MIN || parsed_step > CUSTOM_ACCEL_STEP_MAX) {
+		xf86IDrvMsg(pInfo, X_ERROR, "Invalid step value, ignoring step.\n");
+		return step;
+	}
+
+	if (parsed_step == 0)
+		xf86IDrvMsg(pInfo, X_INFO, "Step value 0 was provided, libinput Fallback acceleration function is used.\n");
+
+	step = parsed_step;
+	return step;
+}
+
+static inline double
+xf86libinput_parse_accel_step_fallback_option(InputInfoPtr pInfo, struct libinput_device *device)
+{
+	return xf86libinput_parse_accel_step_option(pInfo, device, "AccelStepFallback");
+}
+
+static inline double
+xf86libinput_parse_accel_step_motion_option(InputInfoPtr pInfo, struct libinput_device *device)
+{
+	return xf86libinput_parse_accel_step_option(pInfo, device, "AccelStepMotion");
+}
+#endif
+
 static inline BOOL
 xf86libinput_parse_natscroll_option(InputInfoPtr pInfo,
 				    struct libinput_device *device)
@@ -3365,6 +3557,12 @@ xf86libinput_parse_options(InputInfoPtr pInfo,
 	options->tap_button_map = xf86libinput_parse_tap_buttonmap_option(pInfo, device);
 	options->speed = xf86libinput_parse_accel_option(pInfo, device);
 	options->accel_profile = xf86libinput_parse_accel_profile_option(pInfo, device);
+#if HAVE_LIBINPUT_CUSTOM_ACCEL
+	options->accel_points_fallback = xf86libinput_parse_accel_points_fallback_option(pInfo, device);
+	options->accel_points_motion = xf86libinput_parse_accel_points_motion_option(pInfo, device);
+	options->accel_points_fallback.step = xf86libinput_parse_accel_step_fallback_option(pInfo, device);
+	options->accel_points_motion.step = xf86libinput_parse_accel_step_motion_option(pInfo, device);
+#endif
 	options->natural_scrolling = xf86libinput_parse_natscroll_option(pInfo, device);
 	options->sendevents = xf86libinput_parse_sendevents_option(pInfo, device);
 	options->left_handed = xf86libinput_parse_lefthanded_option(pInfo, device);
@@ -3825,6 +4023,12 @@ static Atom prop_calibration_default;
 static Atom prop_accel;
 static Atom prop_accel_default;
 static Atom prop_accel_profile_enabled;
+#if HAVE_LIBINPUT_CUSTOM_ACCEL
+static Atom prop_accel_points_motion;
+static Atom prop_accel_points_fallback;
+static Atom prop_accel_step_motion;
+static Atom prop_accel_step_fallback;
+#endif
 static Atom prop_accel_profile_default;
 static Atom prop_accel_profiles_available;
 static Atom prop_natural_scroll;
@@ -4194,7 +4398,7 @@ LibinputSetPropertyAccelProfile(DeviceIntPtr dev,
 	BOOL* data;
 	uint32_t profiles = 0;
 
-	if (val->format != 8 || val->size != 2 || val->type != XA_INTEGER)
+	if (val->format != 8 || val->size < 2 || val->size > 3 || val->type != XA_INTEGER)
 		return BadMatch;
 
 	data = (BOOL*)val->data;
@@ -4203,6 +4407,10 @@ LibinputSetPropertyAccelProfile(DeviceIntPtr dev,
 		profiles |= LIBINPUT_CONFIG_ACCEL_PROFILE_ADAPTIVE;
 	if (data[1])
 		profiles |= LIBINPUT_CONFIG_ACCEL_PROFILE_FLAT;
+#if HAVE_LIBINPUT_CUSTOM_ACCEL
+	if (val->size > 2 && data[2])
+		profiles |= LIBINPUT_CONFIG_ACCEL_PROFILE_CUSTOM;
+#endif
 
 	if (checkonly) {
 		uint32_t supported;
@@ -4223,6 +4431,92 @@ LibinputSetPropertyAccelProfile(DeviceIntPtr dev,
 	return Success;
 }
 
+#if HAVE_LIBINPUT_CUSTOM_ACCEL
+static inline int
+LibinputSetPropertyAccelPoints(DeviceIntPtr dev,
+			       Atom atom,
+			       XIPropertyValuePtr val,
+			       BOOL checkonly)
+{
+	InputInfoPtr pInfo = dev->public.devicePrivate;
+	struct xf86libinput *driver_data = pInfo->private;
+	struct libinput_device *device = driver_data->shared_device->device;
+	float* data;
+	struct accel_points *accel_points = NULL;
+
+	if (val->format != 32 || val->type != prop_float ||
+	    val->size < CUSTOM_ACCEL_NPOINTS_MIN || val->size > CUSTOM_ACCEL_NPOINTS_MAX)
+		return BadMatch;
+
+	data = (float*)val->data;
+
+	if (checkonly) {
+		uint32_t profiles;
+
+		if (!xf86libinput_check_device(dev, atom))
+			return BadMatch;
+
+		profiles = libinput_device_config_accel_get_profiles(device);
+		if ((profiles & LIBINPUT_CONFIG_ACCEL_PROFILE_CUSTOM) == 0)
+			return BadValue;
+
+		for (size_t idx = 0; idx < val->size; idx++) {
+			if (data[idx] < CUSTOM_ACCEL_POINT_MIN || data[idx] > CUSTOM_ACCEL_POINT_MAX)
+				return BadValue;
+		}
+	} else {
+		if (atom == prop_accel_points_fallback)
+			accel_points = &driver_data->options.accel_points_fallback;
+		else if (atom == prop_accel_points_motion)
+			accel_points = &driver_data->options.accel_points_motion;
+
+		for (size_t idx = 0; idx < val->size; idx++)
+			accel_points->points[idx] = data[idx];
+		accel_points->npoints = val->size;
+	}
+
+	return Success;
+}
+
+static inline int
+LibinputSetPropertyAccelStep(DeviceIntPtr dev,
+			     Atom atom,
+			     XIPropertyValuePtr val,
+			     BOOL checkonly)
+{
+	InputInfoPtr pInfo = dev->public.devicePrivate;
+	struct xf86libinput *driver_data = pInfo->private;
+	struct libinput_device *device = driver_data->shared_device->device;
+	float* data;
+
+	if (val->format != 32 || val->type != prop_float || val->size != 1)
+		return BadMatch;
+
+	data = (float*)val->data;
+
+	if (checkonly) {
+		uint32_t profiles;
+
+		if (!xf86libinput_check_device(dev, atom))
+			return BadMatch;
+
+		profiles = libinput_device_config_accel_get_profiles(device);
+		if ((profiles & LIBINPUT_CONFIG_ACCEL_PROFILE_CUSTOM) == 0)
+			return BadValue;
+
+		if (*data < CUSTOM_ACCEL_STEP_MIN || *data > CUSTOM_ACCEL_STEP_MAX)
+			return BadValue;
+	} else {
+		if (atom == prop_accel_step_fallback)
+			driver_data->options.accel_points_fallback.step = *data;
+		else if (atom == prop_accel_step_motion)
+			driver_data->options.accel_points_motion.step = *data;
+	}
+
+	return Success;
+}
+#endif
+
 static inline int
 LibinputSetPropertyNaturalScroll(DeviceIntPtr dev,
                                  Atom atom,
@@ -4871,6 +5165,12 @@ LibinputSetProperty(DeviceIntPtr dev, Atom atom, XIPropertyValuePtr val,
 		rc = LibinputSetPropertyAccel(dev, atom, val, checkonly);
 	else if (atom == prop_accel_profile_enabled)
 		rc = LibinputSetPropertyAccelProfile(dev, atom, val, checkonly);
+#if HAVE_LIBINPUT_CUSTOM_ACCEL
+	else if (atom == prop_accel_points_fallback || atom == prop_accel_points_motion)
+		rc = LibinputSetPropertyAccelPoints(dev, atom, val, checkonly);
+	else if (atom == prop_accel_step_fallback || atom == prop_accel_step_motion)
+		rc = LibinputSetPropertyAccelStep(dev, atom, val, checkonly);
+#endif
 	else if (atom == prop_natural_scroll)
 		rc = LibinputSetPropertyNaturalScroll(dev, atom, val, checkonly);
 	else if (atom == prop_sendevents_enabled)
@@ -5152,7 +5452,20 @@ LibinputInitAccelProperty(DeviceIntPtr dev,
 	float speed = driver_data->options.speed;
 	uint32_t profile_mask;
 	enum libinput_config_accel_profile profile;
-	BOOL profiles[2] = {FALSE};
+	BOOL profiles[3] = {FALSE};
+#if HAVE_LIBINPUT_CUSTOM_ACCEL
+	float custom_points_fallback[CUSTOM_ACCEL_NPOINTS_MAX] = {0};
+	float custom_points_motion[CUSTOM_ACCEL_NPOINTS_MAX] = {0};
+	size_t custom_npoints_fallback = driver_data->options.accel_points_fallback.npoints;
+	size_t custom_npoints_motion = driver_data->options.accel_points_motion.npoints;
+	float custom_step_fallback = driver_data->options.accel_points_fallback.step;
+	float custom_step_motion = driver_data->options.accel_points_motion.step;
+
+	for (size_t idx = 0; idx < CUSTOM_ACCEL_NPOINTS_MAX; idx++) {
+		custom_points_fallback[idx] = driver_data->options.accel_points_fallback.points[idx];
+		custom_points_motion[idx] = driver_data->options.accel_points_motion.points[idx];
+	}
+#endif
 
 	if (!subdevice_has_capabilities(dev, CAP_POINTER))
 		return;
@@ -5182,6 +5495,10 @@ LibinputInitAccelProperty(DeviceIntPtr dev,
 		profiles[0] = TRUE;
 	if (profile_mask & LIBINPUT_CONFIG_ACCEL_PROFILE_FLAT)
 		profiles[1] = TRUE;
+#if HAVE_LIBINPUT_CUSTOM_ACCEL
+	if (profile_mask & LIBINPUT_CONFIG_ACCEL_PROFILE_CUSTOM)
+		profiles[2] = TRUE;
+#endif
 
 	prop_accel_profiles_available = LibinputMakeProperty(dev,
 							     LIBINPUT_PROP_ACCEL_PROFILES_AVAILABLE,
@@ -5201,6 +5518,11 @@ LibinputInitAccelProperty(DeviceIntPtr dev,
 	case LIBINPUT_CONFIG_ACCEL_PROFILE_FLAT:
 		profiles[1] = TRUE;
 		break;
+#if HAVE_LIBINPUT_CUSTOM_ACCEL
+	case LIBINPUT_CONFIG_ACCEL_PROFILE_CUSTOM:
+		profiles[2] = TRUE;
+		break;
+#endif
 	default:
 		break;
 	}
@@ -5223,6 +5545,11 @@ LibinputInitAccelProperty(DeviceIntPtr dev,
 	case LIBINPUT_CONFIG_ACCEL_PROFILE_FLAT:
 		profiles[1] = TRUE;
 		break;
+#if HAVE_LIBINPUT_CUSTOM_ACCEL
+	case LIBINPUT_CONFIG_ACCEL_PROFILE_CUSTOM:
+		profiles[2] = TRUE;
+		break;
+#endif
 	default:
 		break;
 	}
@@ -5235,6 +5562,26 @@ LibinputInitAccelProperty(DeviceIntPtr dev,
 	if (!prop_accel_profile_default)
 		return;
 
+#if HAVE_LIBINPUT_CUSTOM_ACCEL
+	prop_accel_points_fallback = LibinputMakeProperty(dev,
+							  LIBINPUT_PROP_ACCEL_CUSTOM_POINTS_FALLBACK,
+							  prop_float, 32,
+							  custom_npoints_fallback,
+							  custom_points_fallback);
+	prop_accel_points_motion = LibinputMakeProperty(dev,
+							LIBINPUT_PROP_ACCEL_CUSTOM_POINTS_MOTION,
+							prop_float, 32,
+							custom_npoints_motion,
+							custom_points_motion);
+	prop_accel_step_fallback = LibinputMakeProperty(dev,
+							LIBINPUT_PROP_ACCEL_CUSTOM_STEP_FALLBACK,
+							prop_float, 32, 1,
+							&custom_step_fallback);
+	prop_accel_step_motion = LibinputMakeProperty(dev,
+						      LIBINPUT_PROP_ACCEL_CUSTOM_STEP_MOTION,
+						      prop_float, 32, 1,
+						      &custom_step_motion);
+#endif
 }
 
 static void