firmware: move firmware loader into its own directory

This will make it much easier to manage as we manage to
keep trimming componnents down into their own files to more
easily manage and maintain this codebase.

Suggested-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Luis R. Rodriguez <mcgrof@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

6 files changed, 2062 insertions, 0 deletions

diff --git a/drivers/base/firmware_loader/Makefile b/drivers/base/firmware_loader/Makefile
new file mode 100644
index 000000000000..a97eeb0be1d8
--- /dev/null
+++ b/drivers/base/firmware_loader/Makefile
@@ -0,0 +1,7 @@
+# SPDX-License-Identifier: GPL-2.0
+# Makefile for the Linux firmware loader
+
+obj-y			:= fallback_table.o
+obj-$(CONFIG_FW_LOADER)	+= firmware_class.o
+firmware_class-objs := main.o
+firmware_class-$(CONFIG_FW_LOADER_USER_HELPER) += fallback.o
diff --git a/drivers/base/firmware_loader/fallback.c b/drivers/base/firmware_loader/fallback.c
new file mode 100644
index 000000000000..9b65837256d6
--- /dev/null
+++ b/drivers/base/firmware_loader/fallback.c
@@ -0,0 +1,661 @@
+// SPDX-License-Identifier: GPL-2.0
+
+#include <linux/types.h>
+#include <linux/kconfig.h>
+#include <linux/list.h>
+#include <linux/slab.h>
+#include <linux/security.h>
+#include <linux/highmem.h>
+#include <linux/umh.h>
+
+#include "fallback.h"
+#include "firmware.h"
+
+/*
+ * firmware fallback mechanism
+ */
+
+extern struct firmware_fallback_config fw_fallback_config;
+
+/* These getters are vetted to use int properly */
+static inline int __firmware_loading_timeout(void)
+{
+	return fw_fallback_config.loading_timeout;
+}
+
+/* These setters are vetted to use int properly */
+static void __fw_fallback_set_timeout(int timeout)
+{
+	fw_fallback_config.loading_timeout = timeout;
+}
+
+/*
+ * use small loading timeout for caching devices' firmware because all these
+ * firmware images have been loaded successfully at lease once, also system is
+ * ready for completing firmware loading now. The maximum size of firmware in
+ * current distributions is about 2M bytes, so 10 secs should be enough.
+ */
+void fw_fallback_set_cache_timeout(void)
+{
+	fw_fallback_config.old_timeout = __firmware_loading_timeout();
+	__fw_fallback_set_timeout(10);
+}
+
+/* Restores the timeout to the value last configured during normal operation */
+void fw_fallback_set_default_timeout(void)
+{
+	__fw_fallback_set_timeout(fw_fallback_config.old_timeout);
+}
+
+static long firmware_loading_timeout(void)
+{
+	return __firmware_loading_timeout() > 0 ?
+		__firmware_loading_timeout() * HZ : MAX_JIFFY_OFFSET;
+}
+
+static inline bool fw_sysfs_done(struct fw_priv *fw_priv)
+{
+	return __fw_state_check(fw_priv, FW_STATUS_DONE);
+}
+
+static inline bool fw_sysfs_loading(struct fw_priv *fw_priv)
+{
+	return __fw_state_check(fw_priv, FW_STATUS_LOADING);
+}
+
+static inline int fw_sysfs_wait_timeout(struct fw_priv *fw_priv,  long timeout)
+{
+	return __fw_state_wait_common(fw_priv, timeout);
+}
+
+struct fw_sysfs {
+	bool nowait;
+	struct device dev;
+	struct fw_priv *fw_priv;
+	struct firmware *fw;
+};
+
+static struct fw_sysfs *to_fw_sysfs(struct device *dev)
+{
+	return container_of(dev, struct fw_sysfs, dev);
+}
+
+static void __fw_load_abort(struct fw_priv *fw_priv)
+{
+	/*
+	 * There is a small window in which user can write to 'loading'
+	 * between loading done and disappearance of 'loading'
+	 */
+	if (fw_sysfs_done(fw_priv))
+		return;
+
+	list_del_init(&fw_priv->pending_list);
+	fw_state_aborted(fw_priv);
+}
+
+static void fw_load_abort(struct fw_sysfs *fw_sysfs)
+{
+	struct fw_priv *fw_priv = fw_sysfs->fw_priv;
+
+	__fw_load_abort(fw_priv);
+}
+
+static LIST_HEAD(pending_fw_head);
+
+void kill_pending_fw_fallback_reqs(bool only_kill_custom)
+{
+	struct fw_priv *fw_priv;
+	struct fw_priv *next;
+
+	mutex_lock(&fw_lock);
+	list_for_each_entry_safe(fw_priv, next, &pending_fw_head,
+				 pending_list) {
+		if (!fw_priv->need_uevent || !only_kill_custom)
+			 __fw_load_abort(fw_priv);
+	}
+	mutex_unlock(&fw_lock);
+}
+
+static ssize_t timeout_show(struct class *class, struct class_attribute *attr,
+			    char *buf)
+{
+	return sprintf(buf, "%d\n", __firmware_loading_timeout());
+}
+
+/**
+ * firmware_timeout_store - set number of seconds to wait for firmware
+ * @class: device class pointer
+ * @attr: device attribute pointer
+ * @buf: buffer to scan for timeout value
+ * @count: number of bytes in @buf
+ *
+ *	Sets the number of seconds to wait for the firmware.  Once
+ *	this expires an error will be returned to the driver and no
+ *	firmware will be provided.
+ *
+ *	Note: zero means 'wait forever'.
+ **/
+static ssize_t timeout_store(struct class *class, struct class_attribute *attr,
+			     const char *buf, size_t count)
+{
+	int tmp_loading_timeout = simple_strtol(buf, NULL, 10);
+
+	if (tmp_loading_timeout < 0)
+		tmp_loading_timeout = 0;
+
+	__fw_fallback_set_timeout(tmp_loading_timeout);
+
+	return count;
+}
+static CLASS_ATTR_RW(timeout);
+
+static struct attribute *firmware_class_attrs[] = {
+	&class_attr_timeout.attr,
+	NULL,
+};
+ATTRIBUTE_GROUPS(firmware_class);
+
+static void fw_dev_release(struct device *dev)
+{
+	struct fw_sysfs *fw_sysfs = to_fw_sysfs(dev);
+
+	kfree(fw_sysfs);
+}
+
+static int do_firmware_uevent(struct fw_sysfs *fw_sysfs, struct kobj_uevent_env *env)
+{
+	if (add_uevent_var(env, "FIRMWARE=%s", fw_sysfs->fw_priv->fw_name))
+		return -ENOMEM;
+	if (add_uevent_var(env, "TIMEOUT=%i", __firmware_loading_timeout()))
+		return -ENOMEM;
+	if (add_uevent_var(env, "ASYNC=%d", fw_sysfs->nowait))
+		return -ENOMEM;
+
+	return 0;
+}
+
+static int firmware_uevent(struct device *dev, struct kobj_uevent_env *env)
+{
+	struct fw_sysfs *fw_sysfs = to_fw_sysfs(dev);
+	int err = 0;
+
+	mutex_lock(&fw_lock);
+	if (fw_sysfs->fw_priv)
+		err = do_firmware_uevent(fw_sysfs, env);
+	mutex_unlock(&fw_lock);
+	return err;
+}
+
+static struct class firmware_class = {
+	.name		= "firmware",
+	.class_groups	= firmware_class_groups,
+	.dev_uevent	= firmware_uevent,
+	.dev_release	= fw_dev_release,
+};
+
+int register_sysfs_loader(void)
+{
+	return class_register(&firmware_class);
+}
+
+void unregister_sysfs_loader(void)
+{
+	class_unregister(&firmware_class);
+}
+
+static ssize_t firmware_loading_show(struct device *dev,
+				     struct device_attribute *attr, char *buf)
+{
+	struct fw_sysfs *fw_sysfs = to_fw_sysfs(dev);
+	int loading = 0;
+
+	mutex_lock(&fw_lock);
+	if (fw_sysfs->fw_priv)
+		loading = fw_sysfs_loading(fw_sysfs->fw_priv);
+	mutex_unlock(&fw_lock);
+
+	return sprintf(buf, "%d\n", loading);
+}
+
+/* Some architectures don't have PAGE_KERNEL_RO */
+#ifndef PAGE_KERNEL_RO
+#define PAGE_KERNEL_RO PAGE_KERNEL
+#endif
+
+/* one pages buffer should be mapped/unmapped only once */
+static int map_fw_priv_pages(struct fw_priv *fw_priv)
+{
+	if (!fw_priv->is_paged_buf)
+		return 0;
+
+	vunmap(fw_priv->data);
+	fw_priv->data = vmap(fw_priv->pages, fw_priv->nr_pages, 0,
+			     PAGE_KERNEL_RO);
+	if (!fw_priv->data)
+		return -ENOMEM;
+	return 0;
+}
+
+/**
+ * firmware_loading_store - set value in the 'loading' control file
+ * @dev: device pointer
+ * @attr: device attribute pointer
+ * @buf: buffer to scan for loading control value
+ * @count: number of bytes in @buf
+ *
+ *	The relevant values are:
+ *
+ *	 1: Start a load, discarding any previous partial load.
+ *	 0: Conclude the load and hand the data to the driver code.
+ *	-1: Conclude the load with an error and discard any written data.
+ **/
+static ssize_t firmware_loading_store(struct device *dev,
+				      struct device_attribute *attr,
+				      const char *buf, size_t count)
+{
+	struct fw_sysfs *fw_sysfs = to_fw_sysfs(dev);
+	struct fw_priv *fw_priv;
+	ssize_t written = count;
+	int loading = simple_strtol(buf, NULL, 10);
+	int i;
+
+	mutex_lock(&fw_lock);
+	fw_priv = fw_sysfs->fw_priv;
+	if (fw_state_is_aborted(fw_priv))
+		goto out;
+
+	switch (loading) {
+	case 1:
+		/* discarding any previous partial load */
+		if (!fw_sysfs_done(fw_priv)) {
+			for (i = 0; i < fw_priv->nr_pages; i++)
+				__free_page(fw_priv->pages[i]);
+			vfree(fw_priv->pages);
+			fw_priv->pages = NULL;
+			fw_priv->page_array_size = 0;
+			fw_priv->nr_pages = 0;
+			fw_state_start(fw_priv);
+		}
+		break;
+	case 0:
+		if (fw_sysfs_loading(fw_priv)) {
+			int rc;
+
+			/*
+			 * Several loading requests may be pending on
+			 * one same firmware buf, so let all requests
+			 * see the mapped 'buf->data' once the loading
+			 * is completed.
+			 * */
+			rc = map_fw_priv_pages(fw_priv);
+			if (rc)
+				dev_err(dev, "%s: map pages failed\n",
+					__func__);
+			else
+				rc = security_kernel_post_read_file(NULL,
+						fw_priv->data, fw_priv->size,
+						READING_FIRMWARE);
+
+			/*
+			 * Same logic as fw_load_abort, only the DONE bit
+			 * is ignored and we set ABORT only on failure.
+			 */
+			list_del_init(&fw_priv->pending_list);
+			if (rc) {
+				fw_state_aborted(fw_priv);
+				written = rc;
+			} else {
+				fw_state_done(fw_priv);
+			}
+			break;
+		}
+		/* fallthrough */
+	default:
+		dev_err(dev, "%s: unexpected value (%d)\n", __func__, loading);
+		/* fallthrough */
+	case -1:
+		fw_load_abort(fw_sysfs);
+		break;
+	}
+out:
+	mutex_unlock(&fw_lock);
+	return written;
+}
+
+static DEVICE_ATTR(loading, 0644, firmware_loading_show, firmware_loading_store);
+
+static void firmware_rw_data(struct fw_priv *fw_priv, char *buffer,
+			   loff_t offset, size_t count, bool read)
+{
+	if (read)
+		memcpy(buffer, fw_priv->data + offset, count);
+	else
+		memcpy(fw_priv->data + offset, buffer, count);
+}
+
+static void firmware_rw(struct fw_priv *fw_priv, char *buffer,
+			loff_t offset, size_t count, bool read)
+{
+	while (count) {
+		void *page_data;
+		int page_nr = offset >> PAGE_SHIFT;
+		int page_ofs = offset & (PAGE_SIZE-1);
+		int page_cnt = min_t(size_t, PAGE_SIZE - page_ofs, count);
+
+		page_data = kmap(fw_priv->pages[page_nr]);
+
+		if (read)
+			memcpy(buffer, page_data + page_ofs, page_cnt);
+		else
+			memcpy(page_data + page_ofs, buffer, page_cnt);
+
+		kunmap(fw_priv->pages[page_nr]);
+		buffer += page_cnt;
+		offset += page_cnt;
+		count -= page_cnt;
+	}
+}
+
+static ssize_t firmware_data_read(struct file *filp, struct kobject *kobj,
+				  struct bin_attribute *bin_attr,
+				  char *buffer, loff_t offset, size_t count)
+{
+	struct device *dev = kobj_to_dev(kobj);
+	struct fw_sysfs *fw_sysfs = to_fw_sysfs(dev);
+	struct fw_priv *fw_priv;
+	ssize_t ret_count;
+
+	mutex_lock(&fw_lock);
+	fw_priv = fw_sysfs->fw_priv;
+	if (!fw_priv || fw_sysfs_done(fw_priv)) {
+		ret_count = -ENODEV;
+		goto out;
+	}
+	if (offset > fw_priv->size) {
+		ret_count = 0;
+		goto out;
+	}
+	if (count > fw_priv->size - offset)
+		count = fw_priv->size - offset;
+
+	ret_count = count;
+
+	if (fw_priv->data)
+		firmware_rw_data(fw_priv, buffer, offset, count, true);
+	else
+		firmware_rw(fw_priv, buffer, offset, count, true);
+
+out:
+	mutex_unlock(&fw_lock);
+	return ret_count;
+}
+
+static int fw_realloc_pages(struct fw_sysfs *fw_sysfs, int min_size)
+{
+	struct fw_priv *fw_priv= fw_sysfs->fw_priv;
+	int pages_needed = PAGE_ALIGN(min_size) >> PAGE_SHIFT;
+
+	/* If the array of pages is too small, grow it... */
+	if (fw_priv->page_array_size < pages_needed) {
+		int new_array_size = max(pages_needed,
+					 fw_priv->page_array_size * 2);
+		struct page **new_pages;
+
+		new_pages = vmalloc(new_array_size * sizeof(void *));
+		if (!new_pages) {
+			fw_load_abort(fw_sysfs);
+			return -ENOMEM;
+		}
+		memcpy(new_pages, fw_priv->pages,
+		       fw_priv->page_array_size * sizeof(void *));
+		memset(&new_pages[fw_priv->page_array_size], 0, sizeof(void *) *
+		       (new_array_size - fw_priv->page_array_size));
+		vfree(fw_priv->pages);
+		fw_priv->pages = new_pages;
+		fw_priv->page_array_size = new_array_size;
+	}
+
+	while (fw_priv->nr_pages < pages_needed) {
+		fw_priv->pages[fw_priv->nr_pages] =
+			alloc_page(GFP_KERNEL | __GFP_HIGHMEM);
+
+		if (!fw_priv->pages[fw_priv->nr_pages]) {
+			fw_load_abort(fw_sysfs);
+			return -ENOMEM;
+		}
+		fw_priv->nr_pages++;
+	}
+	return 0;
+}
+
+/**
+ * firmware_data_write - write method for firmware
+ * @filp: open sysfs file
+ * @kobj: kobject for the device
+ * @bin_attr: bin_attr structure
+ * @buffer: buffer being written
+ * @offset: buffer offset for write in total data store area
+ * @count: buffer size
+ *
+ *	Data written to the 'data' attribute will be later handed to
+ *	the driver as a firmware image.
+ **/
+static ssize_t firmware_data_write(struct file *filp, struct kobject *kobj,
+				   struct bin_attribute *bin_attr,
+				   char *buffer, loff_t offset, size_t count)
+{
+	struct device *dev = kobj_to_dev(kobj);
+	struct fw_sysfs *fw_sysfs = to_fw_sysfs(dev);
+	struct fw_priv *fw_priv;
+	ssize_t retval;
+
+	if (!capable(CAP_SYS_RAWIO))
+		return -EPERM;
+
+	mutex_lock(&fw_lock);
+	fw_priv = fw_sysfs->fw_priv;
+	if (!fw_priv || fw_sysfs_done(fw_priv)) {
+		retval = -ENODEV;
+		goto out;
+	}
+
+	if (fw_priv->data) {
+		if (offset + count > fw_priv->allocated_size) {
+			retval = -ENOMEM;
+			goto out;
+		}
+		firmware_rw_data(fw_priv, buffer, offset, count, false);
+		retval = count;
+	} else {
+		retval = fw_realloc_pages(fw_sysfs, offset + count);
+		if (retval)
+			goto out;
+
+		retval = count;
+		firmware_rw(fw_priv, buffer, offset, count, false);
+	}
+
+	fw_priv->size = max_t(size_t, offset + count, fw_priv->size);
+out:
+	mutex_unlock(&fw_lock);
+	return retval;
+}
+
+static struct bin_attribute firmware_attr_data = {
+	.attr = { .name = "data", .mode = 0644 },
+	.size = 0,
+	.read = firmware_data_read,
+	.write = firmware_data_write,
+};
+
+static struct attribute *fw_dev_attrs[] = {
+	&dev_attr_loading.attr,
+	NULL
+};
+
+static struct bin_attribute *fw_dev_bin_attrs[] = {
+	&firmware_attr_data,
+	NULL
+};
+
+static const struct attribute_group fw_dev_attr_group = {
+	.attrs = fw_dev_attrs,
+	.bin_attrs = fw_dev_bin_attrs,
+};
+
+static const struct attribute_group *fw_dev_attr_groups[] = {
+	&fw_dev_attr_group,
+	NULL
+};
+
+static struct fw_sysfs *
+fw_create_instance(struct firmware *firmware, const char *fw_name,
+		   struct device *device, unsigned int opt_flags)
+{
+	struct fw_sysfs *fw_sysfs;
+	struct device *f_dev;
+
+	fw_sysfs = kzalloc(sizeof(*fw_sysfs), GFP_KERNEL);
+	if (!fw_sysfs) {
+		fw_sysfs = ERR_PTR(-ENOMEM);
+		goto exit;
+	}
+
+	fw_sysfs->nowait = !!(opt_flags & FW_OPT_NOWAIT);
+	fw_sysfs->fw = firmware;
+	f_dev = &fw_sysfs->dev;
+
+	device_initialize(f_dev);
+	dev_set_name(f_dev, "%s", fw_name);
+	f_dev->parent = device;
+	f_dev->class = &firmware_class;
+	f_dev->groups = fw_dev_attr_groups;
+exit:
+	return fw_sysfs;
+}
+
+/* load a firmware via user helper */
+static int _request_firmware_load(struct fw_sysfs *fw_sysfs,
+				  unsigned int opt_flags, long timeout)
+{
+	int retval = 0;
+	struct device *f_dev = &fw_sysfs->dev;
+	struct fw_priv *fw_priv = fw_sysfs->fw_priv;
+
+	/* fall back on userspace loading */
+	if (!fw_priv->data)
+		fw_priv->is_paged_buf = true;
+
+	dev_set_uevent_suppress(f_dev, true);
+
+	retval = device_add(f_dev);
+	if (retval) {
+		dev_err(f_dev, "%s: device_register failed\n", __func__);
+		goto err_put_dev;
+	}
+
+	mutex_lock(&fw_lock);
+	list_add(&fw_priv->pending_list, &pending_fw_head);
+	mutex_unlock(&fw_lock);
+
+	if (opt_flags & FW_OPT_UEVENT) {
+		fw_priv->need_uevent = true;
+		dev_set_uevent_suppress(f_dev, false);
+		dev_dbg(f_dev, "firmware: requesting %s\n", fw_priv->fw_name);
+		kobject_uevent(&fw_sysfs->dev.kobj, KOBJ_ADD);
+	} else {
+		timeout = MAX_JIFFY_OFFSET;
+	}
+
+	retval = fw_sysfs_wait_timeout(fw_priv, timeout);
+	if (retval < 0) {
+		mutex_lock(&fw_lock);
+		fw_load_abort(fw_sysfs);
+		mutex_unlock(&fw_lock);
+	}
+
+	if (fw_state_is_aborted(fw_priv)) {
+		if (retval == -ERESTARTSYS)
+			retval = -EINTR;
+		else
+			retval = -EAGAIN;
+	} else if (fw_priv->is_paged_buf && !fw_priv->data)
+		retval = -ENOMEM;
+
+	device_del(f_dev);
+err_put_dev:
+	put_device(f_dev);
+	return retval;
+}
+
+static int fw_load_from_user_helper(struct firmware *firmware,
+				    const char *name, struct device *device,
+				    unsigned int opt_flags)
+{
+	struct fw_sysfs *fw_sysfs;
+	long timeout;
+	int ret;
+
+	timeout = firmware_loading_timeout();
+	if (opt_flags & FW_OPT_NOWAIT) {
+		timeout = usermodehelper_read_lock_wait(timeout);
+		if (!timeout) {
+			dev_dbg(device, "firmware: %s loading timed out\n",
+				name);
+			return -EBUSY;
+		}
+	} else {
+		ret = usermodehelper_read_trylock();
+		if (WARN_ON(ret)) {
+			dev_err(device, "firmware: %s will not be loaded\n",
+				name);
+			return ret;
+		}
+	}
+
+	fw_sysfs = fw_create_instance(firmware, name, device, opt_flags);
+	if (IS_ERR(fw_sysfs)) {
+		ret = PTR_ERR(fw_sysfs);
+		goto out_unlock;
+	}
+
+	fw_sysfs->fw_priv = firmware->priv;
+	ret = _request_firmware_load(fw_sysfs, opt_flags, timeout);
+
+	if (!ret)
+		ret = assign_fw(firmware, device, opt_flags);
+
+out_unlock:
+	usermodehelper_read_unlock();
+
+	return ret;
+}
+
+static bool fw_force_sysfs_fallback(unsigned int opt_flags)
+{
+	if (fw_fallback_config.force_sysfs_fallback)
+		return true;
+	if (!(opt_flags & FW_OPT_USERHELPER))
+		return false;
+	return true;
+}
+
+static bool fw_run_sysfs_fallback(unsigned int opt_flags)
+{
+	if ((opt_flags & FW_OPT_NOFALLBACK))
+		return false;
+
+	return fw_force_sysfs_fallback(opt_flags);
+}
+
+int fw_sysfs_fallback(struct firmware *fw, const char *name,
+		      struct device *device,
+		      unsigned int opt_flags,
+		      int ret)
+{
+	if (!fw_run_sysfs_fallback(opt_flags))
+		return ret;
+
+	dev_warn(device, "Falling back to user helper\n");
+	return fw_load_from_user_helper(fw, name, device, opt_flags);
+}
diff --git a/drivers/base/firmware_loader/fallback.h b/drivers/base/firmware_loader/fallback.h
new file mode 100644
index 000000000000..550498c7fa4c
--- /dev/null
+++ b/drivers/base/firmware_loader/fallback.h
@@ -0,0 +1,61 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#ifndef __FIRMWARE_FALLBACK_H
+#define __FIRMWARE_FALLBACK_H
+
+#include <linux/firmware.h>
+#include <linux/device.h>
+
+/**
+ * struct firmware_fallback_config - firmware fallback configuratioon settings
+ *
+ * Helps describe and fine tune the fallback mechanism.
+ *
+ * @force_sysfs_fallback: force the sysfs fallback mechanism to be used
+ * 	as if one had enabled CONFIG_FW_LOADER_USER_HELPER_FALLBACK=y.
+ * @old_timeout: for internal use
+ * @loading_timeout: the timeout to wait for the fallback mechanism before
+ * 	giving up, in seconds.
+ */
+struct firmware_fallback_config {
+	const bool force_sysfs_fallback;
+	int old_timeout;
+	int loading_timeout;
+};
+
+#ifdef CONFIG_FW_LOADER_USER_HELPER
+int fw_sysfs_fallback(struct firmware *fw, const char *name,
+		      struct device *device,
+		      unsigned int opt_flags,
+		      int ret);
+void kill_pending_fw_fallback_reqs(bool only_kill_custom);
+
+void fw_fallback_set_cache_timeout(void);
+void fw_fallback_set_default_timeout(void);
+
+int register_sysfs_loader(void);
+void unregister_sysfs_loader(void);
+#else /* CONFIG_FW_LOADER_USER_HELPER */
+static inline int fw_sysfs_fallback(struct firmware *fw, const char *name,
+				    struct device *device,
+				    unsigned int opt_flags,
+				    int ret)
+{
+	/* Keep carrying over the same error */
+	return ret;
+}
+
+static inline void kill_pending_fw_fallback_reqs(bool only_kill_custom) { }
+static inline void fw_fallback_set_cache_timeout(void) { }
+static inline void fw_fallback_set_default_timeout(void) { }
+
+static inline int register_sysfs_loader(void)
+{
+	return 0;
+}
+
+static inline void unregister_sysfs_loader(void)
+{
+}
+#endif /* CONFIG_FW_LOADER_USER_HELPER */
+
+#endif /* __FIRMWARE_FALLBACK_H */
diff --git a/drivers/base/firmware_loader/fallback_table.c b/drivers/base/firmware_loader/fallback_table.c
new file mode 100644
index 000000000000..981419044c7e
--- /dev/null
+++ b/drivers/base/firmware_loader/fallback_table.c
@@ -0,0 +1,29 @@
+// SPDX-License-Identifier: GPL-2.0
+
+#include <linux/types.h>
+#include <linux/kconfig.h>
+#include <linux/list.h>
+#include <linux/slab.h>
+#include <linux/security.h>
+#include <linux/highmem.h>
+#include <linux/umh.h>
+#include <linux/sysctl.h>
+
+#include "fallback.h"
+#include "firmware.h"
+
+/*
+ * firmware fallback configuration table
+ */
+
+/* Module or buit-in */
+#ifdef CONFIG_FW_LOADER_USER_HELPER
+
+struct firmware_fallback_config fw_fallback_config = {
+	.force_sysfs_fallback = IS_ENABLED(CONFIG_FW_LOADER_USER_HELPER_FALLBACK),
+	.loading_timeout = 60,
+	.old_timeout = 60,
+};
+EXPORT_SYMBOL_GPL(fw_fallback_config);
+
+#endif
diff --git a/drivers/base/firmware_loader/firmware.h b/drivers/base/firmware_loader/firmware.h
new file mode 100644
index 000000000000..64acbb1a392c
--- /dev/null
+++ b/drivers/base/firmware_loader/firmware.h
@@ -0,0 +1,115 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#ifndef __FIRMWARE_LOADER_H
+#define __FIRMWARE_LOADER_H
+
+#include <linux/firmware.h>
+#include <linux/types.h>
+#include <linux/kref.h>
+#include <linux/list.h>
+#include <linux/completion.h>
+
+#include <generated/utsrelease.h>
+
+/* firmware behavior options */
+#define FW_OPT_UEVENT			(1U << 0)
+#define FW_OPT_NOWAIT			(1U << 1)
+#define FW_OPT_USERHELPER		(1U << 2)
+#define FW_OPT_NO_WARN			(1U << 3)
+#define FW_OPT_NOCACHE			(1U << 4)
+#define FW_OPT_NOFALLBACK		(1U << 5)
+
+enum fw_status {
+	FW_STATUS_UNKNOWN,
+	FW_STATUS_LOADING,
+	FW_STATUS_DONE,
+	FW_STATUS_ABORTED,
+};
+
+/*
+ * Concurrent request_firmware() for the same firmware need to be
+ * serialized.  struct fw_state is simple state machine which hold the
+ * state of the firmware loading.
+ */
+struct fw_state {
+	struct completion completion;
+	enum fw_status status;
+};
+
+struct fw_priv {
+	struct kref ref;
+	struct list_head list;
+	struct firmware_cache *fwc;
+	struct fw_state fw_st;
+	void *data;
+	size_t size;
+	size_t allocated_size;
+#ifdef CONFIG_FW_LOADER_USER_HELPER
+	bool is_paged_buf;
+	bool need_uevent;
+	struct page **pages;
+	int nr_pages;
+	int page_array_size;
+	struct list_head pending_list;
+#endif
+	const char *fw_name;
+};
+
+extern struct mutex fw_lock;
+
+static inline bool __fw_state_check(struct fw_priv *fw_priv,
+				    enum fw_status status)
+{
+	struct fw_state *fw_st = &fw_priv->fw_st;
+
+	return fw_st->status == status;
+}
+
+static inline int __fw_state_wait_common(struct fw_priv *fw_priv, long timeout)
+{
+	struct fw_state *fw_st = &fw_priv->fw_st;
+	long ret;
+
+	ret = wait_for_completion_killable_timeout(&fw_st->completion, timeout);
+	if (ret != 0 && fw_st->status == FW_STATUS_ABORTED)
+		return -ENOENT;
+	if (!ret)
+		return -ETIMEDOUT;
+
+	return ret < 0 ? ret : 0;
+}
+
+static inline void __fw_state_set(struct fw_priv *fw_priv,
+				  enum fw_status status)
+{
+	struct fw_state *fw_st = &fw_priv->fw_st;
+
+	WRITE_ONCE(fw_st->status, status);
+
+	if (status == FW_STATUS_DONE || status == FW_STATUS_ABORTED)
+		complete_all(&fw_st->completion);
+}
+
+static inline void fw_state_aborted(struct fw_priv *fw_priv)
+{
+	__fw_state_set(fw_priv, FW_STATUS_ABORTED);
+}
+
+static inline bool fw_state_is_aborted(struct fw_priv *fw_priv)
+{
+	return __fw_state_check(fw_priv, FW_STATUS_ABORTED);
+}
+
+static inline void fw_state_start(struct fw_priv *fw_priv)
+{
+	__fw_state_set(fw_priv, FW_STATUS_LOADING);
+}
+
+static inline void fw_state_done(struct fw_priv *fw_priv)
+{
+	__fw_state_set(fw_priv, FW_STATUS_DONE);
+}
+
+int assign_fw(struct firmware *fw, struct device *device,
+	      unsigned int opt_flags);
+
+#endif /* __FIRMWARE_LOADER_H */
diff --git a/drivers/base/firmware_loader/main.c b/drivers/base/firmware_loader/main.c
new file mode 100644
index 000000000000..c8966c84bd44
--- /dev/null
+++ b/drivers/base/firmware_loader/main.c
@@ -0,0 +1,1189 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * main.c - Multi purpose firmware loading support
+ *
+ * Copyright (c) 2003 Manuel Estrada Sainz
+ *
+ * Please see Documentation/firmware_class/ for more information.
+ *
+ */
+
+#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
+
+#include <linux/capability.h>
+#include <linux/device.h>
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/timer.h>
+#include <linux/vmalloc.h>
+#include <linux/interrupt.h>
+#include <linux/bitops.h>
+#include <linux/mutex.h>
+#include <linux/workqueue.h>
+#include <linux/highmem.h>
+#include <linux/firmware.h>
+#include <linux/slab.h>
+#include <linux/sched.h>
+#include <linux/file.h>
+#include <linux/list.h>
+#include <linux/fs.h>
+#include <linux/async.h>
+#include <linux/pm.h>
+#include <linux/suspend.h>
+#include <linux/syscore_ops.h>
+#include <linux/reboot.h>
+#include <linux/security.h>
+
+#include <generated/utsrelease.h>
+
+#include "../base.h"
+#include "firmware.h"
+#include "fallback.h"
+
+MODULE_AUTHOR("Manuel Estrada Sainz");
+MODULE_DESCRIPTION("Multi purpose firmware loading support");
+MODULE_LICENSE("GPL");
+
+struct firmware_cache {
+	/* firmware_buf instance will be added into the below list */
+	spinlock_t lock;
+	struct list_head head;
+	int state;
+
+#ifdef CONFIG_PM_SLEEP
+	/*
+	 * Names of firmware images which have been cached successfully
+	 * will be added into the below list so that device uncache
+	 * helper can trace which firmware images have been cached
+	 * before.
+	 */
+	spinlock_t name_lock;
+	struct list_head fw_names;
+
+	struct delayed_work work;
+
+	struct notifier_block   pm_notify;
+#endif
+};
+
+struct fw_cache_entry {
+	struct list_head list;
+	const char *name;
+};
+
+struct fw_name_devm {
+	unsigned long magic;
+	const char *name;
+};
+
+static inline struct fw_priv *to_fw_priv(struct kref *ref)
+{
+	return container_of(ref, struct fw_priv, ref);
+}
+
+#define	FW_LOADER_NO_CACHE	0
+#define	FW_LOADER_START_CACHE	1
+
+/* fw_lock could be moved to 'struct fw_sysfs' but since it is just
+ * guarding for corner cases a global lock should be OK */
+DEFINE_MUTEX(fw_lock);
+
+static struct firmware_cache fw_cache;
+
+/* Builtin firmware support */
+
+#ifdef CONFIG_FW_LOADER
+
+extern struct builtin_fw __start_builtin_fw[];
+extern struct builtin_fw __end_builtin_fw[];
+
+static void fw_copy_to_prealloc_buf(struct firmware *fw,
+				    void *buf, size_t size)
+{
+	if (!buf || size < fw->size)
+		return;
+	memcpy(buf, fw->data, fw->size);
+}
+
+static bool fw_get_builtin_firmware(struct firmware *fw, const char *name,
+				    void *buf, size_t size)
+{
+	struct builtin_fw *b_fw;
+
+	for (b_fw = __start_builtin_fw; b_fw != __end_builtin_fw; b_fw++) {
+		if (strcmp(name, b_fw->name) == 0) {
+			fw->size = b_fw->size;
+			fw->data = b_fw->data;
+			fw_copy_to_prealloc_buf(fw, buf, size);
+
+			return true;
+		}
+	}
+
+	return false;
+}
+
+static bool fw_is_builtin_firmware(const struct firmware *fw)
+{
+	struct builtin_fw *b_fw;
+
+	for (b_fw = __start_builtin_fw; b_fw != __end_builtin_fw; b_fw++)
+		if (fw->data == b_fw->data)
+			return true;
+
+	return false;
+}
+
+#else /* Module case - no builtin firmware support */
+
+static inline bool fw_get_builtin_firmware(struct firmware *fw,
+					   const char *name, void *buf,
+					   size_t size)
+{
+	return false;
+}
+
+static inline bool fw_is_builtin_firmware(const struct firmware *fw)
+{
+	return false;
+}
+#endif
+
+static void fw_state_init(struct fw_priv *fw_priv)
+{
+	struct fw_state *fw_st = &fw_priv->fw_st;
+
+	init_completion(&fw_st->completion);
+	fw_st->status = FW_STATUS_UNKNOWN;
+}
+
+static inline int fw_state_wait(struct fw_priv *fw_priv)
+{
+	return __fw_state_wait_common(fw_priv, MAX_SCHEDULE_TIMEOUT);
+}
+
+static int fw_cache_piggyback_on_request(const char *name);
+
+static struct fw_priv *__allocate_fw_priv(const char *fw_name,
+					  struct firmware_cache *fwc,
+					  void *dbuf, size_t size)
+{
+	struct fw_priv *fw_priv;
+
+	fw_priv = kzalloc(sizeof(*fw_priv), GFP_ATOMIC);
+	if (!fw_priv)
+		return NULL;
+
+	fw_priv->fw_name = kstrdup_const(fw_name, GFP_ATOMIC);
+	if (!fw_priv->fw_name) {
+		kfree(fw_priv);
+		return NULL;
+	}
+
+	kref_init(&fw_priv->ref);
+	fw_priv->fwc = fwc;
+	fw_priv->data = dbuf;
+	fw_priv->allocated_size = size;
+	fw_state_init(fw_priv);
+#ifdef CONFIG_FW_LOADER_USER_HELPER
+	INIT_LIST_HEAD(&fw_priv->pending_list);
+#endif
+
+	pr_debug("%s: fw-%s fw_priv=%p\n", __func__, fw_name, fw_priv);
+
+	return fw_priv;
+}
+
+static struct fw_priv *__lookup_fw_priv(const char *fw_name)
+{
+	struct fw_priv *tmp;
+	struct firmware_cache *fwc = &fw_cache;
+
+	list_for_each_entry(tmp, &fwc->head, list)
+		if (!strcmp(tmp->fw_name, fw_name))
+			return tmp;
+	return NULL;
+}
+
+/* Returns 1 for batching firmware requests with the same name */
+static int alloc_lookup_fw_priv(const char *fw_name,
+				struct firmware_cache *fwc,
+				struct fw_priv **fw_priv, void *dbuf,
+				size_t size)
+{
+	struct fw_priv *tmp;
+
+	spin_lock(&fwc->lock);
+	tmp = __lookup_fw_priv(fw_name);
+	if (tmp) {
+		kref_get(&tmp->ref);
+		spin_unlock(&fwc->lock);
+		*fw_priv = tmp;
+		pr_debug("batched request - sharing the same struct fw_priv and lookup for multiple requests\n");
+		return 1;
+	}
+	tmp = __allocate_fw_priv(fw_name, fwc, dbuf, size);
+	if (tmp)
+		list_add(&tmp->list, &fwc->head);
+	spin_unlock(&fwc->lock);
+
+	*fw_priv = tmp;
+
+	return tmp ? 0 : -ENOMEM;
+}
+
+static void __free_fw_priv(struct kref *ref)
+	__releases(&fwc->lock)
+{
+	struct fw_priv *fw_priv = to_fw_priv(ref);
+	struct firmware_cache *fwc = fw_priv->fwc;
+
+	pr_debug("%s: fw-%s fw_priv=%p data=%p size=%u\n",
+		 __func__, fw_priv->fw_name, fw_priv, fw_priv->data,
+		 (unsigned int)fw_priv->size);
+
+	list_del(&fw_priv->list);
+	spin_unlock(&fwc->lock);
+
+#ifdef CONFIG_FW_LOADER_USER_HELPER
+	if (fw_priv->is_paged_buf) {
+		int i;
+		vunmap(fw_priv->data);
+		for (i = 0; i < fw_priv->nr_pages; i++)
+			__free_page(fw_priv->pages[i]);
+		vfree(fw_priv->pages);
+	} else
+#endif
+	if (!fw_priv->allocated_size)
+		vfree(fw_priv->data);
+	kfree_const(fw_priv->fw_name);
+	kfree(fw_priv);
+}
+
+static void free_fw_priv(struct fw_priv *fw_priv)
+{
+	struct firmware_cache *fwc = fw_priv->fwc;
+	spin_lock(&fwc->lock);
+	if (!kref_put(&fw_priv->ref, __free_fw_priv))
+		spin_unlock(&fwc->lock);
+}
+
+/* direct firmware loading support */
+static char fw_path_para[256];
+static const char * const fw_path[] = {
+	fw_path_para,
+	"/lib/firmware/updates/" UTS_RELEASE,
+	"/lib/firmware/updates",
+	"/lib/firmware/" UTS_RELEASE,
+	"/lib/firmware"
+};
+
+/*
+ * Typical usage is that passing 'firmware_class.path=$CUSTOMIZED_PATH'
+ * from kernel command line because firmware_class is generally built in
+ * kernel instead of module.
+ */
+module_param_string(path, fw_path_para, sizeof(fw_path_para), 0644);
+MODULE_PARM_DESC(path, "customized firmware image search path with a higher priority than default path");
+
+static int
+fw_get_filesystem_firmware(struct device *device, struct fw_priv *fw_priv)
+{
+	loff_t size;
+	int i, len;
+	int rc = -ENOENT;
+	char *path;
+	enum kernel_read_file_id id = READING_FIRMWARE;
+	size_t msize = INT_MAX;
+
+	/* Already populated data member means we're loading into a buffer */
+	if (fw_priv->data) {
+		id = READING_FIRMWARE_PREALLOC_BUFFER;
+		msize = fw_priv->allocated_size;
+	}
+
+	path = __getname();
+	if (!path)
+		return -ENOMEM;
+
+	for (i = 0; i < ARRAY_SIZE(fw_path); i++) {
+		/* skip the unset customized path */
+		if (!fw_path[i][0])
+			continue;
+
+		len = snprintf(path, PATH_MAX, "%s/%s",
+			       fw_path[i], fw_priv->fw_name);
+		if (len >= PATH_MAX) {
+			rc = -ENAMETOOLONG;
+			break;
+		}
+
+		fw_priv->size = 0;
+		rc = kernel_read_file_from_path(path, &fw_priv->data, &size,
+						msize, id);
+		if (rc) {
+			if (rc == -ENOENT)
+				dev_dbg(device, "loading %s failed with error %d\n",
+					 path, rc);
+			else
+				dev_warn(device, "loading %s failed with error %d\n",
+					 path, rc);
+			continue;
+		}
+		dev_dbg(device, "direct-loading %s\n", fw_priv->fw_name);
+		fw_priv->size = size;
+		fw_state_done(fw_priv);
+		break;
+	}
+	__putname(path);
+
+	return rc;
+}
+
+/* firmware holds the ownership of pages */
+static void firmware_free_data(const struct firmware *fw)
+{
+	/* Loaded directly? */
+	if (!fw->priv) {
+		vfree(fw->data);
+		return;
+	}
+	free_fw_priv(fw->priv);
+}
+
+/* store the pages buffer info firmware from buf */
+static void fw_set_page_data(struct fw_priv *fw_priv, struct firmware *fw)
+{
+	fw->priv = fw_priv;
+#ifdef CONFIG_FW_LOADER_USER_HELPER
+	fw->pages = fw_priv->pages;
+#endif
+	fw->size = fw_priv->size;
+	fw->data = fw_priv->data;
+
+	pr_debug("%s: fw-%s fw_priv=%p data=%p size=%u\n",
+		 __func__, fw_priv->fw_name, fw_priv, fw_priv->data,
+		 (unsigned int)fw_priv->size);
+}
+
+#ifdef CONFIG_PM_SLEEP
+static void fw_name_devm_release(struct device *dev, void *res)
+{
+	struct fw_name_devm *fwn = res;
+
+	if (fwn->magic == (unsigned long)&fw_cache)
+		pr_debug("%s: fw_name-%s devm-%p released\n",
+				__func__, fwn->name, res);
+	kfree_const(fwn->name);
+}
+
+static int fw_devm_match(struct device *dev, void *res,
+		void *match_data)
+{
+	struct fw_name_devm *fwn = res;
+
+	return (fwn->magic == (unsigned long)&fw_cache) &&
+		!strcmp(fwn->name, match_data);
+}
+
+static struct fw_name_devm *fw_find_devm_name(struct device *dev,
+		const char *name)
+{
+	struct fw_name_devm *fwn;
+
+	fwn = devres_find(dev, fw_name_devm_release,
+			  fw_devm_match, (void *)name);
+	return fwn;
+}
+
+/* add firmware name into devres list */
+static int fw_add_devm_name(struct device *dev, const char *name)
+{
+	struct fw_name_devm *fwn;
+
+	fwn = fw_find_devm_name(dev, name);
+	if (fwn)
+		return 1;
+
+	fwn = devres_alloc(fw_name_devm_release, sizeof(struct fw_name_devm),
+			   GFP_KERNEL);
+	if (!fwn)
+		return -ENOMEM;
+	fwn->name = kstrdup_const(name, GFP_KERNEL);
+	if (!fwn->name) {
+		devres_free(fwn);
+		return -ENOMEM;
+	}
+
+	fwn->magic = (unsigned long)&fw_cache;
+	devres_add(dev, fwn);
+
+	return 0;
+}
+#else
+static int fw_add_devm_name(struct device *dev, const char *name)
+{
+	return 0;
+}
+#endif
+
+int assign_fw(struct firmware *fw, struct device *device,
+	      unsigned int opt_flags)
+{
+	struct fw_priv *fw_priv = fw->priv;
+
+	mutex_lock(&fw_lock);
+	if (!fw_priv->size || fw_state_is_aborted(fw_priv)) {
+		mutex_unlock(&fw_lock);
+		return -ENOENT;
+	}
+
+	/*
+	 * add firmware name into devres list so that we can auto cache
+	 * and uncache firmware for device.
+	 *
+	 * device may has been deleted already, but the problem
+	 * should be fixed in devres or driver core.
+	 */
+	/* don't cache firmware handled without uevent */
+	if (device && (opt_flags & FW_OPT_UEVENT) &&
+	    !(opt_flags & FW_OPT_NOCACHE))
+		fw_add_devm_name(device, fw_priv->fw_name);
+
+	/*
+	 * After caching firmware image is started, let it piggyback
+	 * on request firmware.
+	 */
+	if (!(opt_flags & FW_OPT_NOCACHE) &&
+	    fw_priv->fwc->state == FW_LOADER_START_CACHE) {
+		if (fw_cache_piggyback_on_request(fw_priv->fw_name))
+			kref_get(&fw_priv->ref);
+	}
+
+	/* pass the pages buffer to driver at the last minute */
+	fw_set_page_data(fw_priv, fw);
+	mutex_unlock(&fw_lock);
+	return 0;
+}
+
+/* prepare firmware and firmware_buf structs;
+ * return 0 if a firmware is already assigned, 1 if need to load one,
+ * or a negative error code
+ */
+static int
+_request_firmware_prepare(struct firmware **firmware_p, const char *name,
+			  struct device *device, void *dbuf, size_t size)
+{
+	struct firmware *firmware;
+	struct fw_priv *fw_priv;
+	int ret;
+
+	*firmware_p = firmware = kzalloc(sizeof(*firmware), GFP_KERNEL);
+	if (!firmware) {
+		dev_err(device, "%s: kmalloc(struct firmware) failed\n",
+			__func__);
+		return -ENOMEM;
+	}
+
+	if (fw_get_builtin_firmware(firmware, name, dbuf, size)) {
+		dev_dbg(device, "using built-in %s\n", name);
+		return 0; /* assigned */
+	}
+
+	ret = alloc_lookup_fw_priv(name, &fw_cache, &fw_priv, dbuf, size);
+
+	/*
+	 * bind with 'priv' now to avoid warning in failure path
+	 * of requesting firmware.
+	 */
+	firmware->priv = fw_priv;
+
+	if (ret > 0) {
+		ret = fw_state_wait(fw_priv);
+		if (!ret) {
+			fw_set_page_data(fw_priv, firmware);
+			return 0; /* assigned */
+		}
+	}
+
+	if (ret < 0)
+		return ret;
+	return 1; /* need to load */
+}
+
+/*
+ * Batched requests need only one wake, we need to do this step last due to the
+ * fallback mechanism. The buf is protected with kref_get(), and it won't be
+ * released until the last user calls release_firmware().
+ *
+ * Failed batched requests are possible as well, in such cases we just share
+ * the struct fw_priv and won't release it until all requests are woken
+ * and have gone through this same path.
+ */
+static void fw_abort_batch_reqs(struct firmware *fw)
+{
+	struct fw_priv *fw_priv;
+
+	/* Loaded directly? */
+	if (!fw || !fw->priv)
+		return;
+
+	fw_priv = fw->priv;
+	if (!fw_state_is_aborted(fw_priv))
+		fw_state_aborted(fw_priv);
+}
+
+/* called from request_firmware() and request_firmware_work_func() */
+static int
+_request_firmware(const struct firmware **firmware_p, const char *name,
+		  struct device *device, void *buf, size_t size,
+		  unsigned int opt_flags)
+{
+	struct firmware *fw = NULL;
+	int ret;
+
+	if (!firmware_p)
+		return -EINVAL;
+
+	if (!name || name[0] == '\0') {
+		ret = -EINVAL;
+		goto out;
+	}
+
+	ret = _request_firmware_prepare(&fw, name, device, buf, size);
+	if (ret <= 0) /* error or already assigned */
+		goto out;
+
+	ret = fw_get_filesystem_firmware(device, fw->priv);
+	if (ret) {
+		if (!(opt_flags & FW_OPT_NO_WARN))
+			dev_warn(device,
+				 "Direct firmware load for %s failed with error %d\n",
+				 name, ret);
+		ret = fw_sysfs_fallback(fw, name, device, opt_flags, ret);
+	} else
+		ret = assign_fw(fw, device, opt_flags);
+
+ out:
+	if (ret < 0) {
+		fw_abort_batch_reqs(fw);
+		release_firmware(fw);
+		fw = NULL;
+	}
+
+	*firmware_p = fw;
+	return ret;
+}
+
+/**
+ * request_firmware: - send firmware request and wait for it
+ * @firmware_p: pointer to firmware image
+ * @name: name of firmware file
+ * @device: device for which firmware is being loaded
+ *
+ *      @firmware_p will be used to return a firmware image by the name
+ *      of @name for device @device.
+ *
+ *      Should be called from user context where sleeping is allowed.
+ *
+ *      @name will be used as $FIRMWARE in the uevent environment and
+ *      should be distinctive enough not to be confused with any other
+ *      firmware image for this or any other device.
+ *
+ *	Caller must hold the reference count of @device.
+ *
+ *	The function can be called safely inside device's suspend and
+ *	resume callback.
+ **/
+int
+request_firmware(const struct firmware **firmware_p, const char *name,
+		 struct device *device)
+{
+	int ret;
+
+	/* Need to pin this module until return */
+	__module_get(THIS_MODULE);
+	ret = _request_firmware(firmware_p, name, device, NULL, 0,
+				FW_OPT_UEVENT);
+	module_put(THIS_MODULE);
+	return ret;
+}
+EXPORT_SYMBOL(request_firmware);
+
+/**
+ * request_firmware_direct: - load firmware directly without usermode helper
+ * @firmware_p: pointer to firmware image
+ * @name: name of firmware file
+ * @device: device for which firmware is being loaded
+ *
+ * This function works pretty much like request_firmware(), but this doesn't
+ * fall back to usermode helper even if the firmware couldn't be loaded
+ * directly from fs.  Hence it's useful for loading optional firmwares, which
+ * aren't always present, without extra long timeouts of udev.
+ **/
+int request_firmware_direct(const struct firmware **firmware_p,
+			    const char *name, struct device *device)
+{
+	int ret;
+
+	__module_get(THIS_MODULE);
+	ret = _request_firmware(firmware_p, name, device, NULL, 0,
+				FW_OPT_UEVENT | FW_OPT_NO_WARN |
+				FW_OPT_NOFALLBACK);
+	module_put(THIS_MODULE);
+	return ret;
+}
+EXPORT_SYMBOL_GPL(request_firmware_direct);
+
+/**
+ * request_firmware_into_buf - load firmware into a previously allocated buffer
+ * @firmware_p: pointer to firmware image
+ * @name: name of firmware file
+ * @device: device for which firmware is being loaded and DMA region allocated
+ * @buf: address of buffer to load firmware into
+ * @size: size of buffer
+ *
+ * This function works pretty much like request_firmware(), but it doesn't
+ * allocate a buffer to hold the firmware data. Instead, the firmware
+ * is loaded directly into the buffer pointed to by @buf and the @firmware_p
+ * data member is pointed at @buf.
+ *
+ * This function doesn't cache firmware either.
+ */
+int
+request_firmware_into_buf(const struct firmware **firmware_p, const char *name,
+			  struct device *device, void *buf, size_t size)
+{
+	int ret;
+
+	__module_get(THIS_MODULE);
+	ret = _request_firmware(firmware_p, name, device, buf, size,
+				FW_OPT_UEVENT | FW_OPT_NOCACHE);
+	module_put(THIS_MODULE);
+	return ret;
+}
+EXPORT_SYMBOL(request_firmware_into_buf);
+
+/**
+ * release_firmware: - release the resource associated with a firmware image
+ * @fw: firmware resource to release
+ **/
+void release_firmware(const struct firmware *fw)
+{
+	if (fw) {
+		if (!fw_is_builtin_firmware(fw))
+			firmware_free_data(fw);
+		kfree(fw);
+	}
+}
+EXPORT_SYMBOL(release_firmware);
+
+/* Async support */
+struct firmware_work {
+	struct work_struct work;
+	struct module *module;
+	const char *name;
+	struct device *device;
+	void *context;
+	void (*cont)(const struct firmware *fw, void *context);
+	unsigned int opt_flags;
+};
+
+static void request_firmware_work_func(struct work_struct *work)
+{
+	struct firmware_work *fw_work;
+	const struct firmware *fw;
+
+	fw_work = container_of(work, struct firmware_work, work);
+
+	_request_firmware(&fw, fw_work->name, fw_work->device, NULL, 0,
+			  fw_work->opt_flags);
+	fw_work->cont(fw, fw_work->context);
+	put_device(fw_work->device); /* taken in request_firmware_nowait() */
+
+	module_put(fw_work->module);
+	kfree_const(fw_work->name);
+	kfree(fw_work);
+}
+
+/**
+ * request_firmware_nowait - asynchronous version of request_firmware
+ * @module: module requesting the firmware
+ * @uevent: sends uevent to copy the firmware image if this flag
+ *	is non-zero else the firmware copy must be done manually.
+ * @name: name of firmware file
+ * @device: device for which firmware is being loaded
+ * @gfp: allocation flags
+ * @context: will be passed over to @cont, and
+ *	@fw may be %NULL if firmware request fails.
+ * @cont: function will be called asynchronously when the firmware
+ *	request is over.
+ *
+ *	Caller must hold the reference count of @device.
+ *
+ *	Asynchronous variant of request_firmware() for user contexts:
+ *		- sleep for as small periods as possible since it may
+ *		  increase kernel boot time of built-in device drivers
+ *		  requesting firmware in their ->probe() methods, if
+ *		  @gfp is GFP_KERNEL.
+ *
+ *		- can't sleep at all if @gfp is GFP_ATOMIC.
+ **/
+int
+request_firmware_nowait(
+	struct module *module, bool uevent,
+	const char *name, struct device *device, gfp_t gfp, void *context,
+	void (*cont)(const struct firmware *fw, void *context))
+{
+	struct firmware_work *fw_work;
+
+	fw_work = kzalloc(sizeof(struct firmware_work), gfp);
+	if (!fw_work)
+		return -ENOMEM;
+
+	fw_work->module = module;
+	fw_work->name = kstrdup_const(name, gfp);
+	if (!fw_work->name) {
+		kfree(fw_work);
+		return -ENOMEM;
+	}
+	fw_work->device = device;
+	fw_work->context = context;
+	fw_work->cont = cont;
+	fw_work->opt_flags = FW_OPT_NOWAIT |
+		(uevent ? FW_OPT_UEVENT : FW_OPT_USERHELPER);
+
+	if (!try_module_get(module)) {
+		kfree_const(fw_work->name);
+		kfree(fw_work);
+		return -EFAULT;
+	}
+
+	get_device(fw_work->device);
+	INIT_WORK(&fw_work->work, request_firmware_work_func);
+	schedule_work(&fw_work->work);
+	return 0;
+}
+EXPORT_SYMBOL(request_firmware_nowait);
+
+#ifdef CONFIG_PM_SLEEP
+static ASYNC_DOMAIN_EXCLUSIVE(fw_cache_domain);
+
+/**
+ * cache_firmware - cache one firmware image in kernel memory space
+ * @fw_name: the firmware image name
+ *
+ * Cache firmware in kernel memory so that drivers can use it when
+ * system isn't ready for them to request firmware image from userspace.
+ * Once it returns successfully, driver can use request_firmware or its
+ * nowait version to get the cached firmware without any interacting
+ * with userspace
+ *
+ * Return 0 if the firmware image has been cached successfully
+ * Return !0 otherwise
+ *
+ */
+static int cache_firmware(const char *fw_name)
+{
+	int ret;
+	const struct firmware *fw;
+
+	pr_debug("%s: %s\n", __func__, fw_name);
+
+	ret = request_firmware(&fw, fw_name, NULL);
+	if (!ret)
+		kfree(fw);
+
+	pr_debug("%s: %s ret=%d\n", __func__, fw_name, ret);
+
+	return ret;
+}
+
+static struct fw_priv *lookup_fw_priv(const char *fw_name)
+{
+	struct fw_priv *tmp;
+	struct firmware_cache *fwc = &fw_cache;
+
+	spin_lock(&fwc->lock);
+	tmp = __lookup_fw_priv(fw_name);
+	spin_unlock(&fwc->lock);
+
+	return tmp;
+}
+
+/**
+ * uncache_firmware - remove one cached firmware image
+ * @fw_name: the firmware image name
+ *
+ * Uncache one firmware image which has been cached successfully
+ * before.
+ *
+ * Return 0 if the firmware cache has been removed successfully
+ * Return !0 otherwise
+ *
+ */
+static int uncache_firmware(const char *fw_name)
+{
+	struct fw_priv *fw_priv;
+	struct firmware fw;
+
+	pr_debug("%s: %s\n", __func__, fw_name);
+
+	if (fw_get_builtin_firmware(&fw, fw_name, NULL, 0))
+		return 0;
+
+	fw_priv = lookup_fw_priv(fw_name);
+	if (fw_priv) {
+		free_fw_priv(fw_priv);
+		return 0;
+	}
+
+	return -EINVAL;
+}
+
+static struct fw_cache_entry *alloc_fw_cache_entry(const char *name)
+{
+	struct fw_cache_entry *fce;
+
+	fce = kzalloc(sizeof(*fce), GFP_ATOMIC);
+	if (!fce)
+		goto exit;
+
+	fce->name = kstrdup_const(name, GFP_ATOMIC);
+	if (!fce->name) {
+		kfree(fce);
+		fce = NULL;
+		goto exit;
+	}
+exit:
+	return fce;
+}
+
+static int __fw_entry_found(const char *name)
+{
+	struct firmware_cache *fwc = &fw_cache;
+	struct fw_cache_entry *fce;
+
+	list_for_each_entry(fce, &fwc->fw_names, list) {
+		if (!strcmp(fce->name, name))
+			return 1;
+	}
+	return 0;
+}
+
+static int fw_cache_piggyback_on_request(const char *name)
+{
+	struct firmware_cache *fwc = &fw_cache;
+	struct fw_cache_entry *fce;
+	int ret = 0;
+
+	spin_lock(&fwc->name_lock);
+	if (__fw_entry_found(name))
+		goto found;
+
+	fce = alloc_fw_cache_entry(name);
+	if (fce) {
+		ret = 1;
+		list_add(&fce->list, &fwc->fw_names);
+		pr_debug("%s: fw: %s\n", __func__, name);
+	}
+found:
+	spin_unlock(&fwc->name_lock);
+	return ret;
+}
+
+static void free_fw_cache_entry(struct fw_cache_entry *fce)
+{
+	kfree_const(fce->name);
+	kfree(fce);
+}
+
+static void __async_dev_cache_fw_image(void *fw_entry,
+				       async_cookie_t cookie)
+{
+	struct fw_cache_entry *fce = fw_entry;
+	struct firmware_cache *fwc = &fw_cache;
+	int ret;
+
+	ret = cache_firmware(fce->name);
+	if (ret) {
+		spin_lock(&fwc->name_lock);
+		list_del(&fce->list);
+		spin_unlock(&fwc->name_lock);
+
+		free_fw_cache_entry(fce);
+	}
+}
+
+/* called with dev->devres_lock held */
+static void dev_create_fw_entry(struct device *dev, void *res,
+				void *data)
+{
+	struct fw_name_devm *fwn = res;
+	const char *fw_name = fwn->name;
+	struct list_head *head = data;
+	struct fw_cache_entry *fce;
+
+	fce = alloc_fw_cache_entry(fw_name);
+	if (fce)
+		list_add(&fce->list, head);
+}
+
+static int devm_name_match(struct device *dev, void *res,
+			   void *match_data)
+{
+	struct fw_name_devm *fwn = res;
+	return (fwn->magic == (unsigned long)match_data);
+}
+
+static void dev_cache_fw_image(struct device *dev, void *data)
+{
+	LIST_HEAD(todo);
+	struct fw_cache_entry *fce;
+	struct fw_cache_entry *fce_next;
+	struct firmware_cache *fwc = &fw_cache;
+
+	devres_for_each_res(dev, fw_name_devm_release,
+			    devm_name_match, &fw_cache,
+			    dev_create_fw_entry, &todo);
+
+	list_for_each_entry_safe(fce, fce_next, &todo, list) {
+		list_del(&fce->list);
+
+		spin_lock(&fwc->name_lock);
+		/* only one cache entry for one firmware */
+		if (!__fw_entry_found(fce->name)) {
+			list_add(&fce->list, &fwc->fw_names);
+		} else {
+			free_fw_cache_entry(fce);
+			fce = NULL;
+		}
+		spin_unlock(&fwc->name_lock);
+
+		if (fce)
+			async_schedule_domain(__async_dev_cache_fw_image,
+					      (void *)fce,
+					      &fw_cache_domain);
+	}
+}
+
+static void __device_uncache_fw_images(void)
+{
+	struct firmware_cache *fwc = &fw_cache;
+	struct fw_cache_entry *fce;
+
+	spin_lock(&fwc->name_lock);
+	while (!list_empty(&fwc->fw_names)) {
+		fce = list_entry(fwc->fw_names.next,
+				struct fw_cache_entry, list);
+		list_del(&fce->list);
+		spin_unlock(&fwc->name_lock);
+
+		uncache_firmware(fce->name);
+		free_fw_cache_entry(fce);
+
+		spin_lock(&fwc->name_lock);
+	}
+	spin_unlock(&fwc->name_lock);
+}
+
+/**
+ * device_cache_fw_images - cache devices' firmware
+ *
+ * If one device called request_firmware or its nowait version
+ * successfully before, the firmware names are recored into the
+ * device's devres link list, so device_cache_fw_images can call
+ * cache_firmware() to cache these firmwares for the device,
+ * then the device driver can load its firmwares easily at
+ * time when system is not ready to complete loading firmware.
+ */
+static void device_cache_fw_images(void)
+{
+	struct firmware_cache *fwc = &fw_cache;
+	DEFINE_WAIT(wait);
+
+	pr_debug("%s\n", __func__);
+
+	/* cancel uncache work */
+	cancel_delayed_work_sync(&fwc->work);
+
+	fw_fallback_set_cache_timeout();
+
+	mutex_lock(&fw_lock);
+	fwc->state = FW_LOADER_START_CACHE;
+	dpm_for_each_dev(NULL, dev_cache_fw_image);
+	mutex_unlock(&fw_lock);
+
+	/* wait for completion of caching firmware for all devices */
+	async_synchronize_full_domain(&fw_cache_domain);
+
+	fw_fallback_set_default_timeout();
+}
+
+/**
+ * device_uncache_fw_images - uncache devices' firmware
+ *
+ * uncache all firmwares which have been cached successfully
+ * by device_uncache_fw_images earlier
+ */
+static void device_uncache_fw_images(void)
+{
+	pr_debug("%s\n", __func__);
+	__device_uncache_fw_images();
+}
+
+static void device_uncache_fw_images_work(struct work_struct *work)
+{
+	device_uncache_fw_images();
+}
+
+/**
+ * device_uncache_fw_images_delay - uncache devices firmwares
+ * @delay: number of milliseconds to delay uncache device firmwares
+ *
+ * uncache all devices's firmwares which has been cached successfully
+ * by device_cache_fw_images after @delay milliseconds.
+ */
+static void device_uncache_fw_images_delay(unsigned long delay)
+{
+	queue_delayed_work(system_power_efficient_wq, &fw_cache.work,
+			   msecs_to_jiffies(delay));
+}
+
+static int fw_pm_notify(struct notifier_block *notify_block,
+			unsigned long mode, void *unused)
+{
+	switch (mode) {
+	case PM_HIBERNATION_PREPARE:
+	case PM_SUSPEND_PREPARE:
+	case PM_RESTORE_PREPARE:
+		/*
+		 * kill pending fallback requests with a custom fallback
+		 * to avoid stalling suspend.
+		 */
+		kill_pending_fw_fallback_reqs(true);
+		device_cache_fw_images();
+		break;
+
+	case PM_POST_SUSPEND:
+	case PM_POST_HIBERNATION:
+	case PM_POST_RESTORE:
+		/*
+		 * In case that system sleep failed and syscore_suspend is
+		 * not called.
+		 */
+		mutex_lock(&fw_lock);
+		fw_cache.state = FW_LOADER_NO_CACHE;
+		mutex_unlock(&fw_lock);
+
+		device_uncache_fw_images_delay(10 * MSEC_PER_SEC);
+		break;
+	}
+
+	return 0;
+}
+
+/* stop caching firmware once syscore_suspend is reached */
+static int fw_suspend(void)
+{
+	fw_cache.state = FW_LOADER_NO_CACHE;
+	return 0;
+}
+
+static struct syscore_ops fw_syscore_ops = {
+	.suspend = fw_suspend,
+};
+
+static int __init register_fw_pm_ops(void)
+{
+	int ret;
+
+	spin_lock_init(&fw_cache.name_lock);
+	INIT_LIST_HEAD(&fw_cache.fw_names);
+
+	INIT_DELAYED_WORK(&fw_cache.work,
+			  device_uncache_fw_images_work);
+
+	fw_cache.pm_notify.notifier_call = fw_pm_notify;
+	ret = register_pm_notifier(&fw_cache.pm_notify);
+	if (ret)
+		return ret;
+
+	register_syscore_ops(&fw_syscore_ops);
+
+	return ret;
+}
+
+static inline void unregister_fw_pm_ops(void)
+{
+	unregister_syscore_ops(&fw_syscore_ops);
+	unregister_pm_notifier(&fw_cache.pm_notify);
+}
+#else
+static int fw_cache_piggyback_on_request(const char *name)
+{
+	return 0;
+}
+static inline int register_fw_pm_ops(void)
+{
+	return 0;
+}
+static inline void unregister_fw_pm_ops(void)
+{
+}
+#endif
+
+static void __init fw_cache_init(void)
+{
+	spin_lock_init(&fw_cache.lock);
+	INIT_LIST_HEAD(&fw_cache.head);
+	fw_cache.state = FW_LOADER_NO_CACHE;
+}
+
+static int fw_shutdown_notify(struct notifier_block *unused1,
+			      unsigned long unused2, void *unused3)
+{
+	/*
+	 * Kill all pending fallback requests to avoid both stalling shutdown,
+	 * and avoid a deadlock with the usermode_lock.
+	 */
+	kill_pending_fw_fallback_reqs(false);
+
+	return NOTIFY_DONE;
+}
+
+static struct notifier_block fw_shutdown_nb = {
+	.notifier_call = fw_shutdown_notify,
+};
+
+static int __init firmware_class_init(void)
+{
+	int ret;
+
+	/* No need to unfold these on exit */
+	fw_cache_init();
+
+	ret = register_fw_pm_ops();
+	if (ret)
+		return ret;
+
+	ret = register_reboot_notifier(&fw_shutdown_nb);
+	if (ret)
+		goto out;
+
+	return register_sysfs_loader();
+
+out:
+	unregister_fw_pm_ops();
+	return ret;
+}
+
+static void __exit firmware_class_exit(void)
+{
+	unregister_fw_pm_ops();
+	unregister_reboot_notifier(&fw_shutdown_nb);
+	unregister_sysfs_loader();
+}
+
+fs_initcall(firmware_class_init);
+module_exit(firmware_class_exit);