kernel: backport of_request_module()

It's needed by NVMEM changes queued for 6.4.

Signed-off-by: Rafał Miłecki <rafal@milecki.pl>

10 files changed, 1274 insertions, 0 deletions

diff --git a/target/linux/generic/backport-5.10/828-v6.4-0001-of-Fix-modalias-string-generation.patch b/target/linux/generic/backport-5.10/828-v6.4-0001-of-Fix-modalias-string-generation.patch
new file mode 100644
index 0000000000..580a897e98
--- /dev/null
+++ b/target/linux/generic/backport-5.10/828-v6.4-0001-of-Fix-modalias-string-generation.patch
@@ -0,0 +1,70 @@
+From b19a4266c52de78496fe40f0b37580a3b762e67d Mon Sep 17 00:00:00 2001
+From: Miquel Raynal <miquel.raynal@bootlin.com>
+Date: Tue, 4 Apr 2023 18:21:09 +0100
+Subject: [PATCH] of: Fix modalias string generation
+
+The helper generating an OF based modalias (of_device_get_modalias())
+works fine, but due to the use of snprintf() internally it needs a
+buffer one byte longer than what should be needed just for the entire
+string (excluding the '\0'). Most users of this helper are sysfs hooks
+providing the modalias string to users. They all provide a PAGE_SIZE
+buffer which is way above the number of bytes required to fit the
+modalias string and hence do not suffer from this issue.
+
+There is another user though, of_device_request_module(), which is only
+called by drivers/usb/common/ulpi.c. This request module function is
+faulty, but maybe because in most cases there is an alternative, ULPI
+driver users have not noticed it.
+
+In this function, of_device_get_modalias() is called twice. The first
+time without buffer just to get the number of bytes required by the
+modalias string (excluding the null byte), and a second time, after
+buffer allocation, to fill the buffer. The allocation asks for an
+additional byte, in order to store the trailing '\0'. However, the
+buffer *length* provided to of_device_get_modalias() excludes this extra
+byte. The internal use of snprintf() with a length that is exactly the
+number of bytes to be written has the effect of using the last available
+byte to store a '\0', which then smashes the last character of the
+modalias string.
+
+Provide the actual size of the buffer to of_device_get_modalias() to fix
+this issue.
+
+Note: the "str[size - 1] = '\0';" line is not really needed as snprintf
+will anyway end the string with a null byte, but there is a possibility
+that this function might be called on a struct device_node without
+compatible, in this case snprintf() would not be executed. So we keep it
+just to avoid possible unbounded strings.
+
+Cc: Stephen Boyd <sboyd@kernel.org>
+Cc: Peter Chen <peter.chen@kernel.org>
+Fixes: 9c829c097f2f ("of: device: Support loading a module with OF based modalias")
+Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>
+Reviewed-by: Rob Herring <robh@kernel.org>
+Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
+Link: https://lore.kernel.org/r/20230404172148.82422-2-srinivas.kandagatla@linaro.org
+Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
+---
+ drivers/of/device.c | 7 +++++--
+ 1 file changed, 5 insertions(+), 2 deletions(-)
+
+--- a/drivers/of/device.c
++++ b/drivers/of/device.c
+@@ -264,12 +264,15 @@ int of_device_request_module(struct devi
+ 	if (size < 0)
+ 		return size;
+ 
+-	str = kmalloc(size + 1, GFP_KERNEL);
++	/* Reserve an additional byte for the trailing '\0' */
++	size++;
++
++	str = kmalloc(size, GFP_KERNEL);
+ 	if (!str)
+ 		return -ENOMEM;
+ 
+ 	of_device_get_modalias(dev, str, size);
+-	str[size] = '\0';
++	str[size - 1] = '\0';
+ 	ret = request_module(str);
+ 	kfree(str);
+ 
diff --git a/target/linux/generic/backport-5.10/828-v6.4-0002-of-Update-of_device_get_modalias.patch b/target/linux/generic/backport-5.10/828-v6.4-0002-of-Update-of_device_get_modalias.patch
new file mode 100644
index 0000000000..eac4ced5ab
--- /dev/null
+++ b/target/linux/generic/backport-5.10/828-v6.4-0002-of-Update-of_device_get_modalias.patch
@@ -0,0 +1,103 @@
+From 5c3d15e127ebfc0754cd18def7124633b6d46672 Mon Sep 17 00:00:00 2001
+From: Miquel Raynal <miquel.raynal@bootlin.com>
+Date: Tue, 4 Apr 2023 18:21:15 +0100
+Subject: [PATCH] of: Update of_device_get_modalias()
+
+This function only needs a "struct device_node" to work, but for
+convenience the author (and only user) of this helper did use a "struct
+device" and put it in device.c.
+
+Let's convert this helper to take a "struct device node" instead. This
+change asks for two additional changes: renaming it "of_modalias()"
+to fit the current naming, and moving it outside of device.c which will
+be done in a follow-up commit.
+
+Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>
+Reviewed-by: Rob Herring <robh@kernel.org>
+Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
+Link: https://lore.kernel.org/r/20230404172148.82422-8-srinivas.kandagatla@linaro.org
+Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
+---
+ drivers/of/device.c | 29 +++++++++++++++++------------
+ 1 file changed, 17 insertions(+), 12 deletions(-)
+
+--- a/drivers/of/device.c
++++ b/drivers/of/device.c
+@@ -215,7 +215,7 @@ const void *of_device_get_match_data(con
+ }
+ EXPORT_SYMBOL(of_device_get_match_data);
+ 
+-static ssize_t of_device_get_modalias(struct device *dev, char *str, ssize_t len)
++static ssize_t of_modalias(const struct device_node *np, char *str, ssize_t len)
+ {
+ 	const char *compat;
+ 	char *c;
+@@ -223,19 +223,16 @@ static ssize_t of_device_get_modalias(st
+ 	ssize_t csize;
+ 	ssize_t tsize;
+ 
+-	if ((!dev) || (!dev->of_node) || dev->of_node_reused)
+-		return -ENODEV;
+-
+ 	/* Name & Type */
+ 	/* %p eats all alphanum characters, so %c must be used here */
+-	csize = snprintf(str, len, "of:N%pOFn%c%s", dev->of_node, 'T',
+-			 of_node_get_device_type(dev->of_node));
++	csize = snprintf(str, len, "of:N%pOFn%c%s", np, 'T',
++			 of_node_get_device_type(np));
+ 	tsize = csize;
+ 	len -= csize;
+ 	if (str)
+ 		str += csize;
+ 
+-	of_property_for_each_string(dev->of_node, "compatible", p, compat) {
++	of_property_for_each_string(np, "compatible", p, compat) {
+ 		csize = strlen(compat) + 1;
+ 		tsize += csize;
+ 		if (csize > len)
+@@ -260,7 +257,10 @@ int of_device_request_module(struct devi
+ 	ssize_t size;
+ 	int ret;
+ 
+-	size = of_device_get_modalias(dev, NULL, 0);
++	if (!dev || !dev->of_node)
++		return -ENODEV;
++
++	size = of_modalias(dev->of_node, NULL, 0);
+ 	if (size < 0)
+ 		return size;
+ 
+@@ -271,7 +271,7 @@ int of_device_request_module(struct devi
+ 	if (!str)
+ 		return -ENOMEM;
+ 
+-	of_device_get_modalias(dev, str, size);
++	of_modalias(dev->of_node, str, size);
+ 	str[size - 1] = '\0';
+ 	ret = request_module(str);
+ 	kfree(str);
+@@ -285,7 +285,12 @@ EXPORT_SYMBOL_GPL(of_device_request_modu
+  */
+ ssize_t of_device_modalias(struct device *dev, char *str, ssize_t len)
+ {
+-	ssize_t sl = of_device_get_modalias(dev, str, len - 2);
++	ssize_t sl;
++
++	if (!dev || !dev->of_node || dev->of_node_reused)
++		return -ENODEV;
++
++	sl = of_modalias(dev->of_node, str, len - 2);
+ 	if (sl < 0)
+ 		return sl;
+ 	if (sl > len - 2)
+@@ -348,8 +353,8 @@ int of_device_uevent_modalias(struct dev
+ 	if (add_uevent_var(env, "MODALIAS="))
+ 		return -ENOMEM;
+ 
+-	sl = of_device_get_modalias(dev, &env->buf[env->buflen-1],
+-				    sizeof(env->buf) - env->buflen);
++	sl = of_modalias(dev->of_node, &env->buf[env->buflen-1],
++			 sizeof(env->buf) - env->buflen);
+ 	if (sl < 0)
+ 		return sl;
+ 	if (sl >= (sizeof(env->buf) - env->buflen))
diff --git a/target/linux/generic/backport-5.10/828-v6.4-0003-of-Rename-of_modalias_node.patch b/target/linux/generic/backport-5.10/828-v6.4-0003-of-Rename-of_modalias_node.patch
new file mode 100644
index 0000000000..7e641211e6
--- /dev/null
+++ b/target/linux/generic/backport-5.10/828-v6.4-0003-of-Rename-of_modalias_node.patch
@@ -0,0 +1,173 @@
+From 673aa1ed1c9b6710bf24e3f0957d85e2f46c77db Mon Sep 17 00:00:00 2001
+From: Miquel Raynal <miquel.raynal@bootlin.com>
+Date: Tue, 4 Apr 2023 18:21:16 +0100
+Subject: [PATCH] of: Rename of_modalias_node()
+
+This helper does not produce a real modalias, but tries to get the
+"product" compatible part of the "vendor,product" compatibles only. It
+is far from creating a purely useful modalias string and does not seem
+to be used like that directly anyway, so let's try to give this helper a
+more meaningful name before moving there a real modalias helper (already
+existing under of/device.c).
+
+Also update the various documentations to refer to the strings as
+"aliases" rather than "modaliases" which has a real meaning in the Linux
+kernel.
+
+There is no functional change.
+
+Cc: Rafael J. Wysocki <rafael@kernel.org>
+Cc: Len Brown <lenb@kernel.org>
+Cc: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
+Cc: Maxime Ripard <mripard@kernel.org>
+Cc: Thomas Zimmermann <tzimmermann@suse.de>
+Cc: Sebastian Reichel <sre@kernel.org>
+Cc: Wolfram Sang <wsa@kernel.org>
+Cc: Mark Brown <broonie@kernel.org>
+Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>
+Reviewed-by: Rob Herring <robh@kernel.org>
+Acked-by: Mark Brown <broonie@kernel.org>
+Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
+Acked-by: Sebastian Reichel <sre@kernel.org>
+Link: https://lore.kernel.org/r/20230404172148.82422-9-srinivas.kandagatla@linaro.org
+Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
+---
+ drivers/acpi/bus.c                |  7 ++++---
+ drivers/gpu/drm/drm_mipi_dsi.c    |  2 +-
+ drivers/hsi/hsi_core.c            |  2 +-
+ drivers/i2c/busses/i2c-powermac.c |  2 +-
+ drivers/i2c/i2c-core-of.c         |  2 +-
+ drivers/of/base.c                 | 18 +++++++++++-------
+ drivers/spi/spi.c                 |  4 ++--
+ include/linux/of.h                |  3 ++-
+ 8 files changed, 23 insertions(+), 17 deletions(-)
+
+--- a/drivers/acpi/bus.c
++++ b/drivers/acpi/bus.c
+@@ -693,9 +693,10 @@ static bool acpi_of_modalias(struct acpi
+  * @modalias:   Pointer to buffer that modalias value will be copied into
+  * @len:	Length of modalias buffer
+  *
+- * This is a counterpart of of_modalias_node() for struct acpi_device objects.
+- * If there is a compatible string for @adev, it will be copied to @modalias
+- * with the vendor prefix stripped; otherwise, @default_id will be used.
++ * This is a counterpart of of_alias_from_compatible() for struct acpi_device
++ * objects. If there is a compatible string for @adev, it will be copied to
++ * @modalias with the vendor prefix stripped; otherwise, @default_id will be
++ * used.
+  */
+ void acpi_set_modalias(struct acpi_device *adev, const char *default_id,
+ 		       char *modalias, size_t len)
+--- a/drivers/gpu/drm/drm_mipi_dsi.c
++++ b/drivers/gpu/drm/drm_mipi_dsi.c
+@@ -160,7 +160,7 @@ of_mipi_dsi_device_add(struct mipi_dsi_h
+ 	int ret;
+ 	u32 reg;
+ 
+-	if (of_modalias_node(node, info.type, sizeof(info.type)) < 0) {
++	if (of_alias_from_compatible(node, info.type, sizeof(info.type)) < 0) {
+ 		drm_err(host, "modalias failure on %pOF\n", node);
+ 		return ERR_PTR(-EINVAL);
+ 	}
+--- a/drivers/hsi/hsi_core.c
++++ b/drivers/hsi/hsi_core.c
+@@ -207,7 +207,7 @@ static void hsi_add_client_from_dt(struc
+ 	if (!cl)
+ 		return;
+ 
+-	err = of_modalias_node(client, name, sizeof(name));
++	err = of_alias_from_compatible(client, name, sizeof(name));
+ 	if (err)
+ 		goto err;
+ 
+--- a/drivers/i2c/busses/i2c-powermac.c
++++ b/drivers/i2c/busses/i2c-powermac.c
+@@ -289,7 +289,7 @@ static bool i2c_powermac_get_type(struct
+ 	 */
+ 
+ 	/* First try proper modalias */
+-	if (of_modalias_node(node, tmp, sizeof(tmp)) >= 0) {
++	if (of_alias_from_compatible(node, tmp, sizeof(tmp)) >= 0) {
+ 		snprintf(type, type_size, "MAC,%s", tmp);
+ 		return true;
+ 	}
+--- a/drivers/i2c/i2c-core-of.c
++++ b/drivers/i2c/i2c-core-of.c
+@@ -27,7 +27,7 @@ int of_i2c_get_board_info(struct device
+ 
+ 	memset(info, 0, sizeof(*info));
+ 
+-	if (of_modalias_node(node, info->type, sizeof(info->type)) < 0) {
++	if (of_alias_from_compatible(node, info->type, sizeof(info->type)) < 0) {
+ 		dev_err(dev, "of_i2c: modalias failure on %pOF\n", node);
+ 		return -EINVAL;
+ 	}
+--- a/drivers/of/base.c
++++ b/drivers/of/base.c
+@@ -1160,19 +1160,23 @@ struct device_node *of_find_matching_nod
+ EXPORT_SYMBOL(of_find_matching_node_and_match);
+ 
+ /**
+- * of_modalias_node - Lookup appropriate modalias for a device node
++ * of_alias_from_compatible - Lookup appropriate alias for a device node
++ *			      depending on compatible
+  * @node:	pointer to a device tree node
+- * @modalias:	Pointer to buffer that modalias value will be copied into
+- * @len:	Length of modalias value
++ * @alias:	Pointer to buffer that alias value will be copied into
++ * @len:	Length of alias value
+  *
+  * Based on the value of the compatible property, this routine will attempt
+- * to choose an appropriate modalias value for a particular device tree node.
++ * to choose an appropriate alias value for a particular device tree node.
+  * It does this by stripping the manufacturer prefix (as delimited by a ',')
+  * from the first entry in the compatible list property.
+  *
++ * Note: The matching on just the "product" side of the compatible is a relic
++ * from I2C and SPI. Please do not add any new user.
++ *
+  * Return: This routine returns 0 on success, <0 on failure.
+  */
+-int of_modalias_node(struct device_node *node, char *modalias, int len)
++int of_alias_from_compatible(const struct device_node *node, char *alias, int len)
+ {
+ 	const char *compatible, *p;
+ 	int cplen;
+@@ -1181,10 +1185,10 @@ int of_modalias_node(struct device_node
+ 	if (!compatible || strlen(compatible) > cplen)
+ 		return -ENODEV;
+ 	p = strchr(compatible, ',');
+-	strlcpy(modalias, p ? p + 1 : compatible, len);
++	strlcpy(alias, p ? p + 1 : compatible, len);
+ 	return 0;
+ }
+-EXPORT_SYMBOL_GPL(of_modalias_node);
++EXPORT_SYMBOL_GPL(of_alias_from_compatible);
+ 
+ /**
+  * of_find_node_by_phandle - Find a node given a phandle
+--- a/drivers/spi/spi.c
++++ b/drivers/spi/spi.c
+@@ -2038,8 +2038,8 @@ of_register_spi_device(struct spi_contro
+ 	}
+ 
+ 	/* Select device driver */
+-	rc = of_modalias_node(nc, spi->modalias,
+-				sizeof(spi->modalias));
++	rc = of_alias_from_compatible(nc, spi->modalias,
++				      sizeof(spi->modalias));
+ 	if (rc < 0) {
+ 		dev_err(&ctlr->dev, "cannot find modalias for %pOF\n", nc);
+ 		goto err_out;
+--- a/include/linux/of.h
++++ b/include/linux/of.h
+@@ -361,7 +361,8 @@ extern int of_n_addr_cells(struct device
+ extern int of_n_size_cells(struct device_node *np);
+ extern const struct of_device_id *of_match_node(
+ 	const struct of_device_id *matches, const struct device_node *node);
+-extern int of_modalias_node(struct device_node *node, char *modalias, int len);
++extern int of_alias_from_compatible(const struct device_node *node, char *alias,
++				    int len);
+ extern void of_print_phandle_args(const char *msg, const struct of_phandle_args *args);
+ extern int __of_parse_phandle_with_args(const struct device_node *np,
+ 	const char *list_name, const char *cells_name, int cell_count,
diff --git a/target/linux/generic/backport-5.10/828-v6.4-0004-of-Move-of_modalias-to-module.c.patch b/target/linux/generic/backport-5.10/828-v6.4-0004-of-Move-of_modalias-to-module.c.patch
new file mode 100644
index 0000000000..62d1232bcd
--- /dev/null
+++ b/target/linux/generic/backport-5.10/828-v6.4-0004-of-Move-of_modalias-to-module.c.patch
@@ -0,0 +1,160 @@
+From bd7a7ed774afd1a4174df34227626c95573be517 Mon Sep 17 00:00:00 2001
+From: Miquel Raynal <miquel.raynal@bootlin.com>
+Date: Tue, 4 Apr 2023 18:21:17 +0100
+Subject: [PATCH] of: Move of_modalias() to module.c
+
+Create a specific .c file for OF related module handling.
+Move of_modalias() inside as a first step.
+
+The helper is exposed through of.h even though it is only used by core
+files because the users from device.c will soon be split into an OF-only
+helper in module.c as well as a device-oriented inline helper in
+of_device.h. Putting this helper in of_private.h would require to
+include of_private.h from of_device.h, which is not acceptable.
+
+Suggested-by: Rob Herring <robh+dt@kernel.org>
+Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>
+Reviewed-by: Rob Herring <robh@kernel.org>
+Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
+Link: https://lore.kernel.org/r/20230404172148.82422-10-srinivas.kandagatla@linaro.org
+Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
+---
+ drivers/of/Makefile |  2 +-
+ drivers/of/device.c | 37 -------------------------------------
+ drivers/of/module.c | 44 ++++++++++++++++++++++++++++++++++++++++++++
+ include/linux/of.h  |  9 +++++++++
+ 4 files changed, 54 insertions(+), 38 deletions(-)
+ create mode 100644 drivers/of/module.c
+
+--- a/drivers/of/Makefile
++++ b/drivers/of/Makefile
+@@ -1,5 +1,5 @@
+ # SPDX-License-Identifier: GPL-2.0
+-obj-y = base.o device.o platform.o property.o
++obj-y = base.o device.o module.o platform.o property.o
+ obj-$(CONFIG_OF_KOBJ) += kobj.o
+ obj-$(CONFIG_OF_DYNAMIC) += dynamic.o
+ obj-$(CONFIG_OF_FLATTREE) += fdt.o
+--- a/drivers/of/device.c
++++ b/drivers/of/device.c
+@@ -1,5 +1,4 @@
+ // SPDX-License-Identifier: GPL-2.0
+-#include <linux/string.h>
+ #include <linux/kernel.h>
+ #include <linux/of.h>
+ #include <linux/of_device.h>
+@@ -215,42 +214,6 @@ const void *of_device_get_match_data(con
+ }
+ EXPORT_SYMBOL(of_device_get_match_data);
+ 
+-static ssize_t of_modalias(const struct device_node *np, char *str, ssize_t len)
+-{
+-	const char *compat;
+-	char *c;
+-	struct property *p;
+-	ssize_t csize;
+-	ssize_t tsize;
+-
+-	/* Name & Type */
+-	/* %p eats all alphanum characters, so %c must be used here */
+-	csize = snprintf(str, len, "of:N%pOFn%c%s", np, 'T',
+-			 of_node_get_device_type(np));
+-	tsize = csize;
+-	len -= csize;
+-	if (str)
+-		str += csize;
+-
+-	of_property_for_each_string(np, "compatible", p, compat) {
+-		csize = strlen(compat) + 1;
+-		tsize += csize;
+-		if (csize > len)
+-			continue;
+-
+-		csize = snprintf(str, len, "C%s", compat);
+-		for (c = str; c; ) {
+-			c = strchr(c, ' ');
+-			if (c)
+-				*c++ = '_';
+-		}
+-		len -= csize;
+-		str += csize;
+-	}
+-
+-	return tsize;
+-}
+-
+ int of_device_request_module(struct device *dev)
+ {
+ 	char *str;
+--- /dev/null
++++ b/drivers/of/module.c
+@@ -0,0 +1,44 @@
++// SPDX-License-Identifier: GPL-2.0
++/*
++ * Linux kernel module helpers.
++ */
++
++#include <linux/of.h>
++#include <linux/slab.h>
++#include <linux/string.h>
++
++ssize_t of_modalias(const struct device_node *np, char *str, ssize_t len)
++{
++	const char *compat;
++	char *c;
++	struct property *p;
++	ssize_t csize;
++	ssize_t tsize;
++
++	/* Name & Type */
++	/* %p eats all alphanum characters, so %c must be used here */
++	csize = snprintf(str, len, "of:N%pOFn%c%s", np, 'T',
++			 of_node_get_device_type(np));
++	tsize = csize;
++	len -= csize;
++	if (str)
++		str += csize;
++
++	of_property_for_each_string(np, "compatible", p, compat) {
++		csize = strlen(compat) + 1;
++		tsize += csize;
++		if (csize > len)
++			continue;
++
++		csize = snprintf(str, len, "C%s", compat);
++		for (c = str; c; ) {
++			c = strchr(c, ' ');
++			if (c)
++				*c++ = '_';
++		}
++		len -= csize;
++		str += csize;
++	}
++
++	return tsize;
++}
+--- a/include/linux/of.h
++++ b/include/linux/of.h
+@@ -373,6 +373,9 @@ extern int of_parse_phandle_with_args_ma
+ extern int of_count_phandle_with_args(const struct device_node *np,
+ 	const char *list_name, const char *cells_name);
+ 
++/* module functions */
++extern ssize_t of_modalias(const struct device_node *np, char *str, ssize_t len);
++
+ /* phandle iterator functions */
+ extern int of_phandle_iterator_init(struct of_phandle_iterator *it,
+ 				    const struct device_node *np,
+@@ -878,6 +881,12 @@ static inline int of_count_phandle_with_
+ 	return -ENOSYS;
+ }
+ 
++static inline ssize_t of_modalias(const struct device_node *np, char *str,
++				  ssize_t len)
++{
++	return -ENODEV;
++}
++
+ static inline int of_phandle_iterator_init(struct of_phandle_iterator *it,
+ 					   const struct device_node *np,
+ 					   const char *list_name,
diff --git a/target/linux/generic/backport-5.10/828-v6.4-0005-of-Move-the-request-module-helper-logic-to-module.c.patch b/target/linux/generic/backport-5.10/828-v6.4-0005-of-Move-the-request-module-helper-logic-to-module.c.patch
new file mode 100644
index 0000000000..c176ff8f13
--- /dev/null
+++ b/target/linux/generic/backport-5.10/828-v6.4-0005-of-Move-the-request-module-helper-logic-to-module.c.patch
@@ -0,0 +1,131 @@
+From e6506f06d5e82765666902ccf9e9162f3e31d518 Mon Sep 17 00:00:00 2001
+From: Miquel Raynal <miquel.raynal@bootlin.com>
+Date: Tue, 4 Apr 2023 18:21:18 +0100
+Subject: [PATCH] of: Move the request module helper logic to module.c
+
+Depending on device.c for pure OF handling is considered
+backwards. Let's extract the content of of_device_request_module() to
+have the real logic under module.c.
+
+The next step will be to convert users of of_device_request_module() to
+use the new helper.
+
+Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>
+Reviewed-by: Rob Herring <robh@kernel.org>
+Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
+Link: https://lore.kernel.org/r/20230404172148.82422-11-srinivas.kandagatla@linaro.org
+Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
+---
+ drivers/of/device.c | 25 ++-----------------------
+ drivers/of/module.c | 30 ++++++++++++++++++++++++++++++
+ include/linux/of.h  |  6 ++++++
+ 3 files changed, 38 insertions(+), 23 deletions(-)
+
+--- a/drivers/of/device.c
++++ b/drivers/of/device.c
+@@ -7,7 +7,6 @@
+ #include <linux/dma-direct.h> /* for bus_dma_region */
+ #include <linux/dma-map-ops.h>
+ #include <linux/init.h>
+-#include <linux/module.h>
+ #include <linux/mod_devicetable.h>
+ #include <linux/slab.h>
+ #include <linux/platform_device.h>
+@@ -216,30 +215,10 @@ EXPORT_SYMBOL(of_device_get_match_data);
+ 
+ int of_device_request_module(struct device *dev)
+ {
+-	char *str;
+-	ssize_t size;
+-	int ret;
+-
+-	if (!dev || !dev->of_node)
++	if (!dev)
+ 		return -ENODEV;
+ 
+-	size = of_modalias(dev->of_node, NULL, 0);
+-	if (size < 0)
+-		return size;
+-
+-	/* Reserve an additional byte for the trailing '\0' */
+-	size++;
+-
+-	str = kmalloc(size, GFP_KERNEL);
+-	if (!str)
+-		return -ENOMEM;
+-
+-	of_modalias(dev->of_node, str, size);
+-	str[size - 1] = '\0';
+-	ret = request_module(str);
+-	kfree(str);
+-
+-	return ret;
++	return of_request_module(dev->of_node);
+ }
+ EXPORT_SYMBOL_GPL(of_device_request_module);
+ 
+--- a/drivers/of/module.c
++++ b/drivers/of/module.c
+@@ -4,6 +4,7 @@
+  */
+ 
+ #include <linux/of.h>
++#include <linux/module.h>
+ #include <linux/slab.h>
+ #include <linux/string.h>
+ 
+@@ -42,3 +43,32 @@ ssize_t of_modalias(const struct device_
+ 
+ 	return tsize;
+ }
++
++int of_request_module(const struct device_node *np)
++{
++	char *str;
++	ssize_t size;
++	int ret;
++
++	if (!np)
++		return -ENODEV;
++
++	size = of_modalias(np, NULL, 0);
++	if (size < 0)
++		return size;
++
++	/* Reserve an additional byte for the trailing '\0' */
++	size++;
++
++	str = kmalloc(size, GFP_KERNEL);
++	if (!str)
++		return -ENOMEM;
++
++	of_modalias(np, str, size);
++	str[size - 1] = '\0';
++	ret = request_module(str);
++	kfree(str);
++
++	return ret;
++}
++EXPORT_SYMBOL_GPL(of_request_module);
+--- a/include/linux/of.h
++++ b/include/linux/of.h
+@@ -375,6 +375,7 @@ extern int of_count_phandle_with_args(co
+ 
+ /* module functions */
+ extern ssize_t of_modalias(const struct device_node *np, char *str, ssize_t len);
++extern int of_request_module(const struct device_node *np);
+ 
+ /* phandle iterator functions */
+ extern int of_phandle_iterator_init(struct of_phandle_iterator *it,
+@@ -886,6 +887,11 @@ static inline ssize_t of_modalias(const
+ {
+ 	return -ENODEV;
+ }
++
++static inline int of_request_module(const struct device_node *np)
++{
++	return -ENODEV;
++}
+ 
+ static inline int of_phandle_iterator_init(struct of_phandle_iterator *it,
+ 					   const struct device_node *np,
diff --git a/target/linux/generic/backport-5.15/828-v6.4-0001-of-Fix-modalias-string-generation.patch b/target/linux/generic/backport-5.15/828-v6.4-0001-of-Fix-modalias-string-generation.patch
new file mode 100644
index 0000000000..b5f89289fa
--- /dev/null
+++ b/target/linux/generic/backport-5.15/828-v6.4-0001-of-Fix-modalias-string-generation.patch
@@ -0,0 +1,70 @@
+From b19a4266c52de78496fe40f0b37580a3b762e67d Mon Sep 17 00:00:00 2001
+From: Miquel Raynal <miquel.raynal@bootlin.com>
+Date: Tue, 4 Apr 2023 18:21:09 +0100
+Subject: [PATCH] of: Fix modalias string generation
+
+The helper generating an OF based modalias (of_device_get_modalias())
+works fine, but due to the use of snprintf() internally it needs a
+buffer one byte longer than what should be needed just for the entire
+string (excluding the '\0'). Most users of this helper are sysfs hooks
+providing the modalias string to users. They all provide a PAGE_SIZE
+buffer which is way above the number of bytes required to fit the
+modalias string and hence do not suffer from this issue.
+
+There is another user though, of_device_request_module(), which is only
+called by drivers/usb/common/ulpi.c. This request module function is
+faulty, but maybe because in most cases there is an alternative, ULPI
+driver users have not noticed it.
+
+In this function, of_device_get_modalias() is called twice. The first
+time without buffer just to get the number of bytes required by the
+modalias string (excluding the null byte), and a second time, after
+buffer allocation, to fill the buffer. The allocation asks for an
+additional byte, in order to store the trailing '\0'. However, the
+buffer *length* provided to of_device_get_modalias() excludes this extra
+byte. The internal use of snprintf() with a length that is exactly the
+number of bytes to be written has the effect of using the last available
+byte to store a '\0', which then smashes the last character of the
+modalias string.
+
+Provide the actual size of the buffer to of_device_get_modalias() to fix
+this issue.
+
+Note: the "str[size - 1] = '\0';" line is not really needed as snprintf
+will anyway end the string with a null byte, but there is a possibility
+that this function might be called on a struct device_node without
+compatible, in this case snprintf() would not be executed. So we keep it
+just to avoid possible unbounded strings.
+
+Cc: Stephen Boyd <sboyd@kernel.org>
+Cc: Peter Chen <peter.chen@kernel.org>
+Fixes: 9c829c097f2f ("of: device: Support loading a module with OF based modalias")
+Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>
+Reviewed-by: Rob Herring <robh@kernel.org>
+Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
+Link: https://lore.kernel.org/r/20230404172148.82422-2-srinivas.kandagatla@linaro.org
+Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
+---
+ drivers/of/device.c | 7 +++++--
+ 1 file changed, 5 insertions(+), 2 deletions(-)
+
+--- a/drivers/of/device.c
++++ b/drivers/of/device.c
+@@ -290,12 +290,15 @@ int of_device_request_module(struct devi
+ 	if (size < 0)
+ 		return size;
+ 
+-	str = kmalloc(size + 1, GFP_KERNEL);
++	/* Reserve an additional byte for the trailing '\0' */
++	size++;
++
++	str = kmalloc(size, GFP_KERNEL);
+ 	if (!str)
+ 		return -ENOMEM;
+ 
+ 	of_device_get_modalias(dev, str, size);
+-	str[size] = '\0';
++	str[size - 1] = '\0';
+ 	ret = request_module(str);
+ 	kfree(str);
+ 
diff --git a/target/linux/generic/backport-5.15/828-v6.4-0002-of-Update-of_device_get_modalias.patch b/target/linux/generic/backport-5.15/828-v6.4-0002-of-Update-of_device_get_modalias.patch
new file mode 100644
index 0000000000..4713cc71b1
--- /dev/null
+++ b/target/linux/generic/backport-5.15/828-v6.4-0002-of-Update-of_device_get_modalias.patch
@@ -0,0 +1,103 @@
+From 5c3d15e127ebfc0754cd18def7124633b6d46672 Mon Sep 17 00:00:00 2001
+From: Miquel Raynal <miquel.raynal@bootlin.com>
+Date: Tue, 4 Apr 2023 18:21:15 +0100
+Subject: [PATCH] of: Update of_device_get_modalias()
+
+This function only needs a "struct device_node" to work, but for
+convenience the author (and only user) of this helper did use a "struct
+device" and put it in device.c.
+
+Let's convert this helper to take a "struct device node" instead. This
+change asks for two additional changes: renaming it "of_modalias()"
+to fit the current naming, and moving it outside of device.c which will
+be done in a follow-up commit.
+
+Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>
+Reviewed-by: Rob Herring <robh@kernel.org>
+Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
+Link: https://lore.kernel.org/r/20230404172148.82422-8-srinivas.kandagatla@linaro.org
+Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
+---
+ drivers/of/device.c | 29 +++++++++++++++++------------
+ 1 file changed, 17 insertions(+), 12 deletions(-)
+
+--- a/drivers/of/device.c
++++ b/drivers/of/device.c
+@@ -241,7 +241,7 @@ const void *of_device_get_match_data(con
+ }
+ EXPORT_SYMBOL(of_device_get_match_data);
+ 
+-static ssize_t of_device_get_modalias(struct device *dev, char *str, ssize_t len)
++static ssize_t of_modalias(const struct device_node *np, char *str, ssize_t len)
+ {
+ 	const char *compat;
+ 	char *c;
+@@ -249,19 +249,16 @@ static ssize_t of_device_get_modalias(st
+ 	ssize_t csize;
+ 	ssize_t tsize;
+ 
+-	if ((!dev) || (!dev->of_node) || dev->of_node_reused)
+-		return -ENODEV;
+-
+ 	/* Name & Type */
+ 	/* %p eats all alphanum characters, so %c must be used here */
+-	csize = snprintf(str, len, "of:N%pOFn%c%s", dev->of_node, 'T',
+-			 of_node_get_device_type(dev->of_node));
++	csize = snprintf(str, len, "of:N%pOFn%c%s", np, 'T',
++			 of_node_get_device_type(np));
+ 	tsize = csize;
+ 	len -= csize;
+ 	if (str)
+ 		str += csize;
+ 
+-	of_property_for_each_string(dev->of_node, "compatible", p, compat) {
++	of_property_for_each_string(np, "compatible", p, compat) {
+ 		csize = strlen(compat) + 1;
+ 		tsize += csize;
+ 		if (csize > len)
+@@ -286,7 +283,10 @@ int of_device_request_module(struct devi
+ 	ssize_t size;
+ 	int ret;
+ 
+-	size = of_device_get_modalias(dev, NULL, 0);
++	if (!dev || !dev->of_node)
++		return -ENODEV;
++
++	size = of_modalias(dev->of_node, NULL, 0);
+ 	if (size < 0)
+ 		return size;
+ 
+@@ -297,7 +297,7 @@ int of_device_request_module(struct devi
+ 	if (!str)
+ 		return -ENOMEM;
+ 
+-	of_device_get_modalias(dev, str, size);
++	of_modalias(dev->of_node, str, size);
+ 	str[size - 1] = '\0';
+ 	ret = request_module(str);
+ 	kfree(str);
+@@ -314,7 +314,12 @@ EXPORT_SYMBOL_GPL(of_device_request_modu
+  */
+ ssize_t of_device_modalias(struct device *dev, char *str, ssize_t len)
+ {
+-	ssize_t sl = of_device_get_modalias(dev, str, len - 2);
++	ssize_t sl;
++
++	if (!dev || !dev->of_node || dev->of_node_reused)
++		return -ENODEV;
++
++	sl = of_modalias(dev->of_node, str, len - 2);
+ 	if (sl < 0)
+ 		return sl;
+ 	if (sl > len - 2)
+@@ -379,8 +384,8 @@ int of_device_uevent_modalias(struct dev
+ 	if (add_uevent_var(env, "MODALIAS="))
+ 		return -ENOMEM;
+ 
+-	sl = of_device_get_modalias(dev, &env->buf[env->buflen-1],
+-				    sizeof(env->buf) - env->buflen);
++	sl = of_modalias(dev->of_node, &env->buf[env->buflen-1],
++			 sizeof(env->buf) - env->buflen);
+ 	if (sl < 0)
+ 		return sl;
+ 	if (sl >= (sizeof(env->buf) - env->buflen))
diff --git a/target/linux/generic/backport-5.15/828-v6.4-0003-of-Rename-of_modalias_node.patch b/target/linux/generic/backport-5.15/828-v6.4-0003-of-Rename-of_modalias_node.patch
new file mode 100644
index 0000000000..6c20521701
--- /dev/null
+++ b/target/linux/generic/backport-5.15/828-v6.4-0003-of-Rename-of_modalias_node.patch
@@ -0,0 +1,173 @@
+From 673aa1ed1c9b6710bf24e3f0957d85e2f46c77db Mon Sep 17 00:00:00 2001
+From: Miquel Raynal <miquel.raynal@bootlin.com>
+Date: Tue, 4 Apr 2023 18:21:16 +0100
+Subject: [PATCH] of: Rename of_modalias_node()
+
+This helper does not produce a real modalias, but tries to get the
+"product" compatible part of the "vendor,product" compatibles only. It
+is far from creating a purely useful modalias string and does not seem
+to be used like that directly anyway, so let's try to give this helper a
+more meaningful name before moving there a real modalias helper (already
+existing under of/device.c).
+
+Also update the various documentations to refer to the strings as
+"aliases" rather than "modaliases" which has a real meaning in the Linux
+kernel.
+
+There is no functional change.
+
+Cc: Rafael J. Wysocki <rafael@kernel.org>
+Cc: Len Brown <lenb@kernel.org>
+Cc: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
+Cc: Maxime Ripard <mripard@kernel.org>
+Cc: Thomas Zimmermann <tzimmermann@suse.de>
+Cc: Sebastian Reichel <sre@kernel.org>
+Cc: Wolfram Sang <wsa@kernel.org>
+Cc: Mark Brown <broonie@kernel.org>
+Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>
+Reviewed-by: Rob Herring <robh@kernel.org>
+Acked-by: Mark Brown <broonie@kernel.org>
+Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
+Acked-by: Sebastian Reichel <sre@kernel.org>
+Link: https://lore.kernel.org/r/20230404172148.82422-9-srinivas.kandagatla@linaro.org
+Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
+---
+ drivers/acpi/bus.c                |  7 ++++---
+ drivers/gpu/drm/drm_mipi_dsi.c    |  2 +-
+ drivers/hsi/hsi_core.c            |  2 +-
+ drivers/i2c/busses/i2c-powermac.c |  2 +-
+ drivers/i2c/i2c-core-of.c         |  2 +-
+ drivers/of/base.c                 | 18 +++++++++++-------
+ drivers/spi/spi.c                 |  4 ++--
+ include/linux/of.h                |  3 ++-
+ 8 files changed, 23 insertions(+), 17 deletions(-)
+
+--- a/drivers/acpi/bus.c
++++ b/drivers/acpi/bus.c
+@@ -785,9 +785,10 @@ static bool acpi_of_modalias(struct acpi
+  * @modalias:   Pointer to buffer that modalias value will be copied into
+  * @len:	Length of modalias buffer
+  *
+- * This is a counterpart of of_modalias_node() for struct acpi_device objects.
+- * If there is a compatible string for @adev, it will be copied to @modalias
+- * with the vendor prefix stripped; otherwise, @default_id will be used.
++ * This is a counterpart of of_alias_from_compatible() for struct acpi_device
++ * objects. If there is a compatible string for @adev, it will be copied to
++ * @modalias with the vendor prefix stripped; otherwise, @default_id will be
++ * used.
+  */
+ void acpi_set_modalias(struct acpi_device *adev, const char *default_id,
+ 		       char *modalias, size_t len)
+--- a/drivers/gpu/drm/drm_mipi_dsi.c
++++ b/drivers/gpu/drm/drm_mipi_dsi.c
+@@ -160,7 +160,7 @@ of_mipi_dsi_device_add(struct mipi_dsi_h
+ 	int ret;
+ 	u32 reg;
+ 
+-	if (of_modalias_node(node, info.type, sizeof(info.type)) < 0) {
++	if (of_alias_from_compatible(node, info.type, sizeof(info.type)) < 0) {
+ 		drm_err(host, "modalias failure on %pOF\n", node);
+ 		return ERR_PTR(-EINVAL);
+ 	}
+--- a/drivers/hsi/hsi_core.c
++++ b/drivers/hsi/hsi_core.c
+@@ -207,7 +207,7 @@ static void hsi_add_client_from_dt(struc
+ 	if (!cl)
+ 		return;
+ 
+-	err = of_modalias_node(client, name, sizeof(name));
++	err = of_alias_from_compatible(client, name, sizeof(name));
+ 	if (err)
+ 		goto err;
+ 
+--- a/drivers/i2c/busses/i2c-powermac.c
++++ b/drivers/i2c/busses/i2c-powermac.c
+@@ -284,7 +284,7 @@ static bool i2c_powermac_get_type(struct
+ 	 */
+ 
+ 	/* First try proper modalias */
+-	if (of_modalias_node(node, tmp, sizeof(tmp)) >= 0) {
++	if (of_alias_from_compatible(node, tmp, sizeof(tmp)) >= 0) {
+ 		snprintf(type, type_size, "MAC,%s", tmp);
+ 		return true;
+ 	}
+--- a/drivers/i2c/i2c-core-of.c
++++ b/drivers/i2c/i2c-core-of.c
+@@ -27,7 +27,7 @@ int of_i2c_get_board_info(struct device
+ 
+ 	memset(info, 0, sizeof(*info));
+ 
+-	if (of_modalias_node(node, info->type, sizeof(info->type)) < 0) {
++	if (of_alias_from_compatible(node, info->type, sizeof(info->type)) < 0) {
+ 		dev_err(dev, "of_i2c: modalias failure on %pOF\n", node);
+ 		return -EINVAL;
+ 	}
+--- a/drivers/of/base.c
++++ b/drivers/of/base.c
+@@ -1159,19 +1159,23 @@ struct device_node *of_find_matching_nod
+ EXPORT_SYMBOL(of_find_matching_node_and_match);
+ 
+ /**
+- * of_modalias_node - Lookup appropriate modalias for a device node
++ * of_alias_from_compatible - Lookup appropriate alias for a device node
++ *			      depending on compatible
+  * @node:	pointer to a device tree node
+- * @modalias:	Pointer to buffer that modalias value will be copied into
+- * @len:	Length of modalias value
++ * @alias:	Pointer to buffer that alias value will be copied into
++ * @len:	Length of alias value
+  *
+  * Based on the value of the compatible property, this routine will attempt
+- * to choose an appropriate modalias value for a particular device tree node.
++ * to choose an appropriate alias value for a particular device tree node.
+  * It does this by stripping the manufacturer prefix (as delimited by a ',')
+  * from the first entry in the compatible list property.
+  *
++ * Note: The matching on just the "product" side of the compatible is a relic
++ * from I2C and SPI. Please do not add any new user.
++ *
+  * Return: This routine returns 0 on success, <0 on failure.
+  */
+-int of_modalias_node(struct device_node *node, char *modalias, int len)
++int of_alias_from_compatible(const struct device_node *node, char *alias, int len)
+ {
+ 	const char *compatible, *p;
+ 	int cplen;
+@@ -1180,10 +1184,10 @@ int of_modalias_node(struct device_node
+ 	if (!compatible || strlen(compatible) > cplen)
+ 		return -ENODEV;
+ 	p = strchr(compatible, ',');
+-	strlcpy(modalias, p ? p + 1 : compatible, len);
++	strlcpy(alias, p ? p + 1 : compatible, len);
+ 	return 0;
+ }
+-EXPORT_SYMBOL_GPL(of_modalias_node);
++EXPORT_SYMBOL_GPL(of_alias_from_compatible);
+ 
+ /**
+  * of_find_node_by_phandle - Find a node given a phandle
+--- a/drivers/spi/spi.c
++++ b/drivers/spi/spi.c
+@@ -2128,8 +2128,8 @@ of_register_spi_device(struct spi_contro
+ 	}
+ 
+ 	/* Select device driver */
+-	rc = of_modalias_node(nc, spi->modalias,
+-				sizeof(spi->modalias));
++	rc = of_alias_from_compatible(nc, spi->modalias,
++				      sizeof(spi->modalias));
+ 	if (rc < 0) {
+ 		dev_err(&ctlr->dev, "cannot find modalias for %pOF\n", nc);
+ 		goto err_out;
+--- a/include/linux/of.h
++++ b/include/linux/of.h
+@@ -361,7 +361,8 @@ extern int of_n_addr_cells(struct device
+ extern int of_n_size_cells(struct device_node *np);
+ extern const struct of_device_id *of_match_node(
+ 	const struct of_device_id *matches, const struct device_node *node);
+-extern int of_modalias_node(struct device_node *node, char *modalias, int len);
++extern int of_alias_from_compatible(const struct device_node *node, char *alias,
++				    int len);
+ extern void of_print_phandle_args(const char *msg, const struct of_phandle_args *args);
+ extern int __of_parse_phandle_with_args(const struct device_node *np,
+ 	const char *list_name, const char *cells_name, int cell_count,
diff --git a/target/linux/generic/backport-5.15/828-v6.4-0004-of-Move-of_modalias-to-module.c.patch b/target/linux/generic/backport-5.15/828-v6.4-0004-of-Move-of_modalias-to-module.c.patch
new file mode 100644
index 0000000000..a70c6f2eec
--- /dev/null
+++ b/target/linux/generic/backport-5.15/828-v6.4-0004-of-Move-of_modalias-to-module.c.patch
@@ -0,0 +1,160 @@
+From bd7a7ed774afd1a4174df34227626c95573be517 Mon Sep 17 00:00:00 2001
+From: Miquel Raynal <miquel.raynal@bootlin.com>
+Date: Tue, 4 Apr 2023 18:21:17 +0100
+Subject: [PATCH] of: Move of_modalias() to module.c
+
+Create a specific .c file for OF related module handling.
+Move of_modalias() inside as a first step.
+
+The helper is exposed through of.h even though it is only used by core
+files because the users from device.c will soon be split into an OF-only
+helper in module.c as well as a device-oriented inline helper in
+of_device.h. Putting this helper in of_private.h would require to
+include of_private.h from of_device.h, which is not acceptable.
+
+Suggested-by: Rob Herring <robh+dt@kernel.org>
+Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>
+Reviewed-by: Rob Herring <robh@kernel.org>
+Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
+Link: https://lore.kernel.org/r/20230404172148.82422-10-srinivas.kandagatla@linaro.org
+Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
+---
+ drivers/of/Makefile |  2 +-
+ drivers/of/device.c | 37 -------------------------------------
+ drivers/of/module.c | 44 ++++++++++++++++++++++++++++++++++++++++++++
+ include/linux/of.h  |  9 +++++++++
+ 4 files changed, 54 insertions(+), 38 deletions(-)
+ create mode 100644 drivers/of/module.c
+
+--- a/drivers/of/Makefile
++++ b/drivers/of/Makefile
+@@ -1,5 +1,5 @@
+ # SPDX-License-Identifier: GPL-2.0
+-obj-y = base.o device.o platform.o property.o
++obj-y = base.o device.o module.o platform.o property.o
+ obj-$(CONFIG_OF_KOBJ) += kobj.o
+ obj-$(CONFIG_OF_DYNAMIC) += dynamic.o
+ obj-$(CONFIG_OF_FLATTREE) += fdt.o
+--- a/drivers/of/device.c
++++ b/drivers/of/device.c
+@@ -1,5 +1,4 @@
+ // SPDX-License-Identifier: GPL-2.0
+-#include <linux/string.h>
+ #include <linux/kernel.h>
+ #include <linux/of.h>
+ #include <linux/of_device.h>
+@@ -241,42 +240,6 @@ const void *of_device_get_match_data(con
+ }
+ EXPORT_SYMBOL(of_device_get_match_data);
+ 
+-static ssize_t of_modalias(const struct device_node *np, char *str, ssize_t len)
+-{
+-	const char *compat;
+-	char *c;
+-	struct property *p;
+-	ssize_t csize;
+-	ssize_t tsize;
+-
+-	/* Name & Type */
+-	/* %p eats all alphanum characters, so %c must be used here */
+-	csize = snprintf(str, len, "of:N%pOFn%c%s", np, 'T',
+-			 of_node_get_device_type(np));
+-	tsize = csize;
+-	len -= csize;
+-	if (str)
+-		str += csize;
+-
+-	of_property_for_each_string(np, "compatible", p, compat) {
+-		csize = strlen(compat) + 1;
+-		tsize += csize;
+-		if (csize > len)
+-			continue;
+-
+-		csize = snprintf(str, len, "C%s", compat);
+-		for (c = str; c; ) {
+-			c = strchr(c, ' ');
+-			if (c)
+-				*c++ = '_';
+-		}
+-		len -= csize;
+-		str += csize;
+-	}
+-
+-	return tsize;
+-}
+-
+ int of_device_request_module(struct device *dev)
+ {
+ 	char *str;
+--- /dev/null
++++ b/drivers/of/module.c
+@@ -0,0 +1,44 @@
++// SPDX-License-Identifier: GPL-2.0
++/*
++ * Linux kernel module helpers.
++ */
++
++#include <linux/of.h>
++#include <linux/slab.h>
++#include <linux/string.h>
++
++ssize_t of_modalias(const struct device_node *np, char *str, ssize_t len)
++{
++	const char *compat;
++	char *c;
++	struct property *p;
++	ssize_t csize;
++	ssize_t tsize;
++
++	/* Name & Type */
++	/* %p eats all alphanum characters, so %c must be used here */
++	csize = snprintf(str, len, "of:N%pOFn%c%s", np, 'T',
++			 of_node_get_device_type(np));
++	tsize = csize;
++	len -= csize;
++	if (str)
++		str += csize;
++
++	of_property_for_each_string(np, "compatible", p, compat) {
++		csize = strlen(compat) + 1;
++		tsize += csize;
++		if (csize > len)
++			continue;
++
++		csize = snprintf(str, len, "C%s", compat);
++		for (c = str; c; ) {
++			c = strchr(c, ' ');
++			if (c)
++				*c++ = '_';
++		}
++		len -= csize;
++		str += csize;
++	}
++
++	return tsize;
++}
+--- a/include/linux/of.h
++++ b/include/linux/of.h
+@@ -373,6 +373,9 @@ extern int of_parse_phandle_with_args_ma
+ extern int of_count_phandle_with_args(const struct device_node *np,
+ 	const char *list_name, const char *cells_name);
+ 
++/* module functions */
++extern ssize_t of_modalias(const struct device_node *np, char *str, ssize_t len);
++
+ /* phandle iterator functions */
+ extern int of_phandle_iterator_init(struct of_phandle_iterator *it,
+ 				    const struct device_node *np,
+@@ -885,6 +888,12 @@ static inline int of_count_phandle_with_
+ 	return -ENOSYS;
+ }
+ 
++static inline ssize_t of_modalias(const struct device_node *np, char *str,
++				  ssize_t len)
++{
++	return -ENODEV;
++}
++
+ static inline int of_phandle_iterator_init(struct of_phandle_iterator *it,
+ 					   const struct device_node *np,
+ 					   const char *list_name,
diff --git a/target/linux/generic/backport-5.15/828-v6.4-0005-of-Move-the-request-module-helper-logic-to-module.c.patch b/target/linux/generic/backport-5.15/828-v6.4-0005-of-Move-the-request-module-helper-logic-to-module.c.patch
new file mode 100644
index 0000000000..06bc24ca6e
--- /dev/null
+++ b/target/linux/generic/backport-5.15/828-v6.4-0005-of-Move-the-request-module-helper-logic-to-module.c.patch
@@ -0,0 +1,131 @@
+From e6506f06d5e82765666902ccf9e9162f3e31d518 Mon Sep 17 00:00:00 2001
+From: Miquel Raynal <miquel.raynal@bootlin.com>
+Date: Tue, 4 Apr 2023 18:21:18 +0100
+Subject: [PATCH] of: Move the request module helper logic to module.c
+
+Depending on device.c for pure OF handling is considered
+backwards. Let's extract the content of of_device_request_module() to
+have the real logic under module.c.
+
+The next step will be to convert users of of_device_request_module() to
+use the new helper.
+
+Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>
+Reviewed-by: Rob Herring <robh@kernel.org>
+Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
+Link: https://lore.kernel.org/r/20230404172148.82422-11-srinivas.kandagatla@linaro.org
+Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
+---
+ drivers/of/device.c | 25 ++-----------------------
+ drivers/of/module.c | 30 ++++++++++++++++++++++++++++++
+ include/linux/of.h  |  6 ++++++
+ 3 files changed, 38 insertions(+), 23 deletions(-)
+
+--- a/drivers/of/device.c
++++ b/drivers/of/device.c
+@@ -8,7 +8,6 @@
+ #include <linux/dma-direct.h> /* for bus_dma_region */
+ #include <linux/dma-map-ops.h>
+ #include <linux/init.h>
+-#include <linux/module.h>
+ #include <linux/mod_devicetable.h>
+ #include <linux/slab.h>
+ #include <linux/platform_device.h>
+@@ -242,30 +241,10 @@ EXPORT_SYMBOL(of_device_get_match_data);
+ 
+ int of_device_request_module(struct device *dev)
+ {
+-	char *str;
+-	ssize_t size;
+-	int ret;
+-
+-	if (!dev || !dev->of_node)
++	if (!dev)
+ 		return -ENODEV;
+ 
+-	size = of_modalias(dev->of_node, NULL, 0);
+-	if (size < 0)
+-		return size;
+-
+-	/* Reserve an additional byte for the trailing '\0' */
+-	size++;
+-
+-	str = kmalloc(size, GFP_KERNEL);
+-	if (!str)
+-		return -ENOMEM;
+-
+-	of_modalias(dev->of_node, str, size);
+-	str[size - 1] = '\0';
+-	ret = request_module(str);
+-	kfree(str);
+-
+-	return ret;
++	return of_request_module(dev->of_node);
+ }
+ EXPORT_SYMBOL_GPL(of_device_request_module);
+ 
+--- a/drivers/of/module.c
++++ b/drivers/of/module.c
+@@ -4,6 +4,7 @@
+  */
+ 
+ #include <linux/of.h>
++#include <linux/module.h>
+ #include <linux/slab.h>
+ #include <linux/string.h>
+ 
+@@ -42,3 +43,32 @@ ssize_t of_modalias(const struct device_
+ 
+ 	return tsize;
+ }
++
++int of_request_module(const struct device_node *np)
++{
++	char *str;
++	ssize_t size;
++	int ret;
++
++	if (!np)
++		return -ENODEV;
++
++	size = of_modalias(np, NULL, 0);
++	if (size < 0)
++		return size;
++
++	/* Reserve an additional byte for the trailing '\0' */
++	size++;
++
++	str = kmalloc(size, GFP_KERNEL);
++	if (!str)
++		return -ENOMEM;
++
++	of_modalias(np, str, size);
++	str[size - 1] = '\0';
++	ret = request_module(str);
++	kfree(str);
++
++	return ret;
++}
++EXPORT_SYMBOL_GPL(of_request_module);
+--- a/include/linux/of.h
++++ b/include/linux/of.h
+@@ -375,6 +375,7 @@ extern int of_count_phandle_with_args(co
+ 
+ /* module functions */
+ extern ssize_t of_modalias(const struct device_node *np, char *str, ssize_t len);
++extern int of_request_module(const struct device_node *np);
+ 
+ /* phandle iterator functions */
+ extern int of_phandle_iterator_init(struct of_phandle_iterator *it,
+@@ -893,6 +894,11 @@ static inline ssize_t of_modalias(const
+ {
+ 	return -ENODEV;
+ }
++
++static inline int of_request_module(const struct device_node *np)
++{
++	return -ENODEV;
++}
+ 
+ static inline int of_phandle_iterator_init(struct of_phandle_iterator *it,
+ 					   const struct device_node *np,