summaryrefslogtreecommitdiffstats
path: root/kernel/drivers/base/firmware_class.c
diff options
context:
space:
mode:
Diffstat (limited to 'kernel/drivers/base/firmware_class.c')
-rw-r--r--kernel/drivers/base/firmware_class.c1686
1 files changed, 1686 insertions, 0 deletions
diff --git a/kernel/drivers/base/firmware_class.c b/kernel/drivers/base/firmware_class.c
new file mode 100644
index 000000000..171841ad1
--- /dev/null
+++ b/kernel/drivers/base/firmware_class.c
@@ -0,0 +1,1686 @@
+/*
+ * firmware_class.c - Multi purpose firmware loading support
+ *
+ * Copyright (c) 2003 Manuel Estrada Sainz
+ *
+ * Please see Documentation/firmware_class/ for more information.
+ *
+ */
+
+#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/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"
+
+MODULE_AUTHOR("Manuel Estrada Sainz");
+MODULE_DESCRIPTION("Multi purpose firmware loading support");
+MODULE_LICENSE("GPL");
+
+/* Builtin firmware support */
+
+#ifdef CONFIG_FW_LOADER
+
+extern struct builtin_fw __start_builtin_fw[];
+extern struct builtin_fw __end_builtin_fw[];
+
+static bool fw_get_builtin_firmware(struct firmware *fw, const char *name)
+{
+ 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;
+ 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)
+{
+ return false;
+}
+
+static inline bool fw_is_builtin_firmware(const struct firmware *fw)
+{
+ return false;
+}
+#endif
+
+enum {
+ FW_STATUS_LOADING,
+ FW_STATUS_DONE,
+ FW_STATUS_ABORT,
+};
+
+static int loading_timeout = 60; /* In seconds */
+
+static inline long firmware_loading_timeout(void)
+{
+ return loading_timeout > 0 ? loading_timeout * HZ : MAX_JIFFY_OFFSET;
+}
+
+/* firmware behavior options */
+#define FW_OPT_UEVENT (1U << 0)
+#define FW_OPT_NOWAIT (1U << 1)
+#ifdef CONFIG_FW_LOADER_USER_HELPER
+#define FW_OPT_USERHELPER (1U << 2)
+#else
+#define FW_OPT_USERHELPER 0
+#endif
+#ifdef CONFIG_FW_LOADER_USER_HELPER_FALLBACK
+#define FW_OPT_FALLBACK FW_OPT_USERHELPER
+#else
+#define FW_OPT_FALLBACK 0
+#endif
+#define FW_OPT_NO_WARN (1U << 3)
+
+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 firmware_buf {
+ struct kref ref;
+ struct list_head list;
+ struct completion completion;
+ struct firmware_cache *fwc;
+ unsigned long status;
+ void *data;
+ size_t 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
+ char fw_id[];
+};
+
+struct fw_cache_entry {
+ struct list_head list;
+ char name[];
+};
+
+struct fw_name_devm {
+ unsigned long magic;
+ char name[];
+};
+
+#define to_fwbuf(d) container_of(d, struct firmware_buf, ref)
+
+#define FW_LOADER_NO_CACHE 0
+#define FW_LOADER_START_CACHE 1
+
+static int fw_cache_piggyback_on_request(const char *name);
+
+/* fw_lock could be moved to 'struct firmware_priv' but since it is just
+ * guarding for corner cases a global lock should be OK */
+static DEFINE_MUTEX(fw_lock);
+
+static struct firmware_cache fw_cache;
+
+static struct firmware_buf *__allocate_fw_buf(const char *fw_name,
+ struct firmware_cache *fwc)
+{
+ struct firmware_buf *buf;
+
+ buf = kzalloc(sizeof(*buf) + strlen(fw_name) + 1, GFP_ATOMIC);
+
+ if (!buf)
+ return buf;
+
+ kref_init(&buf->ref);
+ strcpy(buf->fw_id, fw_name);
+ buf->fwc = fwc;
+ init_completion(&buf->completion);
+#ifdef CONFIG_FW_LOADER_USER_HELPER
+ INIT_LIST_HEAD(&buf->pending_list);
+#endif
+
+ pr_debug("%s: fw-%s buf=%p\n", __func__, fw_name, buf);
+
+ return buf;
+}
+
+static struct firmware_buf *__fw_lookup_buf(const char *fw_name)
+{
+ struct firmware_buf *tmp;
+ struct firmware_cache *fwc = &fw_cache;
+
+ list_for_each_entry(tmp, &fwc->head, list)
+ if (!strcmp(tmp->fw_id, fw_name))
+ return tmp;
+ return NULL;
+}
+
+static int fw_lookup_and_allocate_buf(const char *fw_name,
+ struct firmware_cache *fwc,
+ struct firmware_buf **buf)
+{
+ struct firmware_buf *tmp;
+
+ spin_lock(&fwc->lock);
+ tmp = __fw_lookup_buf(fw_name);
+ if (tmp) {
+ kref_get(&tmp->ref);
+ spin_unlock(&fwc->lock);
+ *buf = tmp;
+ return 1;
+ }
+ tmp = __allocate_fw_buf(fw_name, fwc);
+ if (tmp)
+ list_add(&tmp->list, &fwc->head);
+ spin_unlock(&fwc->lock);
+
+ *buf = tmp;
+
+ return tmp ? 0 : -ENOMEM;
+}
+
+static void __fw_free_buf(struct kref *ref)
+ __releases(&fwc->lock)
+{
+ struct firmware_buf *buf = to_fwbuf(ref);
+ struct firmware_cache *fwc = buf->fwc;
+
+ pr_debug("%s: fw-%s buf=%p data=%p size=%u\n",
+ __func__, buf->fw_id, buf, buf->data,
+ (unsigned int)buf->size);
+
+ list_del(&buf->list);
+ spin_unlock(&fwc->lock);
+
+#ifdef CONFIG_FW_LOADER_USER_HELPER
+ if (buf->is_paged_buf) {
+ int i;
+ vunmap(buf->data);
+ for (i = 0; i < buf->nr_pages; i++)
+ __free_page(buf->pages[i]);
+ kfree(buf->pages);
+ } else
+#endif
+ vfree(buf->data);
+ kfree(buf);
+}
+
+static void fw_free_buf(struct firmware_buf *buf)
+{
+ struct firmware_cache *fwc = buf->fwc;
+ spin_lock(&fwc->lock);
+ if (!kref_put(&buf->ref, __fw_free_buf))
+ 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_read_file_contents(struct file *file, struct firmware_buf *fw_buf)
+{
+ int size;
+ char *buf;
+ int rc;
+
+ if (!S_ISREG(file_inode(file)->i_mode))
+ return -EINVAL;
+ size = i_size_read(file_inode(file));
+ if (size <= 0)
+ return -EINVAL;
+ buf = vmalloc(size);
+ if (!buf)
+ return -ENOMEM;
+ rc = kernel_read(file, 0, buf, size);
+ if (rc != size) {
+ if (rc > 0)
+ rc = -EIO;
+ goto fail;
+ }
+ rc = security_kernel_fw_from_file(file, buf, size);
+ if (rc)
+ goto fail;
+ fw_buf->data = buf;
+ fw_buf->size = size;
+ return 0;
+fail:
+ vfree(buf);
+ return rc;
+}
+
+static int fw_get_filesystem_firmware(struct device *device,
+ struct firmware_buf *buf)
+{
+ int i;
+ int rc = -ENOENT;
+ char *path = __getname();
+
+ for (i = 0; i < ARRAY_SIZE(fw_path); i++) {
+ struct file *file;
+
+ /* skip the unset customized path */
+ if (!fw_path[i][0])
+ continue;
+
+ snprintf(path, PATH_MAX, "%s/%s", fw_path[i], buf->fw_id);
+
+ file = filp_open(path, O_RDONLY, 0);
+ if (IS_ERR(file))
+ continue;
+ rc = fw_read_file_contents(file, buf);
+ fput(file);
+ if (rc)
+ dev_warn(device, "firmware, attempted to load %s, but failed with error %d\n",
+ path, rc);
+ else
+ break;
+ }
+ __putname(path);
+
+ if (!rc) {
+ dev_dbg(device, "firmware: direct-loading firmware %s\n",
+ buf->fw_id);
+ mutex_lock(&fw_lock);
+ set_bit(FW_STATUS_DONE, &buf->status);
+ complete_all(&buf->completion);
+ mutex_unlock(&fw_lock);
+ }
+
+ 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;
+ }
+ fw_free_buf(fw->priv);
+}
+
+/* store the pages buffer info firmware from buf */
+static void fw_set_page_data(struct firmware_buf *buf, struct firmware *fw)
+{
+ fw->priv = buf;
+#ifdef CONFIG_FW_LOADER_USER_HELPER
+ fw->pages = buf->pages;
+#endif
+ fw->size = buf->size;
+ fw->data = buf->data;
+
+ pr_debug("%s: fw-%s buf=%p data=%p size=%u\n",
+ __func__, buf->fw_id, buf, buf->data,
+ (unsigned int)buf->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);
+}
+
+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) +
+ strlen(name) + 1, GFP_KERNEL);
+ if (!fwn)
+ return -ENOMEM;
+
+ fwn->magic = (unsigned long)&fw_cache;
+ strcpy(fwn->name, name);
+ devres_add(dev, fwn);
+
+ return 0;
+}
+#else
+static int fw_add_devm_name(struct device *dev, const char *name)
+{
+ return 0;
+}
+#endif
+
+
+/*
+ * user-mode helper code
+ */
+#ifdef CONFIG_FW_LOADER_USER_HELPER
+struct firmware_priv {
+ bool nowait;
+ struct device dev;
+ struct firmware_buf *buf;
+ struct firmware *fw;
+};
+
+static struct firmware_priv *to_firmware_priv(struct device *dev)
+{
+ return container_of(dev, struct firmware_priv, dev);
+}
+
+static void __fw_load_abort(struct firmware_buf *buf)
+{
+ /*
+ * There is a small window in which user can write to 'loading'
+ * between loading done and disappearance of 'loading'
+ */
+ if (test_bit(FW_STATUS_DONE, &buf->status))
+ return;
+
+ list_del_init(&buf->pending_list);
+ set_bit(FW_STATUS_ABORT, &buf->status);
+ complete_all(&buf->completion);
+}
+
+static void fw_load_abort(struct firmware_priv *fw_priv)
+{
+ struct firmware_buf *buf = fw_priv->buf;
+
+ __fw_load_abort(buf);
+
+ /* avoid user action after loading abort */
+ fw_priv->buf = NULL;
+}
+
+#define is_fw_load_aborted(buf) \
+ test_bit(FW_STATUS_ABORT, &(buf)->status)
+
+static LIST_HEAD(pending_fw_head);
+
+/* reboot notifier for avoid deadlock with usermode_lock */
+static int fw_shutdown_notify(struct notifier_block *unused1,
+ unsigned long unused2, void *unused3)
+{
+ mutex_lock(&fw_lock);
+ while (!list_empty(&pending_fw_head))
+ __fw_load_abort(list_first_entry(&pending_fw_head,
+ struct firmware_buf,
+ pending_list));
+ mutex_unlock(&fw_lock);
+ return NOTIFY_DONE;
+}
+
+static struct notifier_block fw_shutdown_nb = {
+ .notifier_call = fw_shutdown_notify,
+};
+
+static ssize_t timeout_show(struct class *class, struct class_attribute *attr,
+ char *buf)
+{
+ return sprintf(buf, "%d\n", 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)
+{
+ loading_timeout = simple_strtol(buf, NULL, 10);
+ if (loading_timeout < 0)
+ loading_timeout = 0;
+
+ return count;
+}
+
+static struct class_attribute firmware_class_attrs[] = {
+ __ATTR_RW(timeout),
+ __ATTR_NULL
+};
+
+static void fw_dev_release(struct device *dev)
+{
+ struct firmware_priv *fw_priv = to_firmware_priv(dev);
+
+ kfree(fw_priv);
+}
+
+static int firmware_uevent(struct device *dev, struct kobj_uevent_env *env)
+{
+ struct firmware_priv *fw_priv = to_firmware_priv(dev);
+
+ if (add_uevent_var(env, "FIRMWARE=%s", fw_priv->buf->fw_id))
+ return -ENOMEM;
+ if (add_uevent_var(env, "TIMEOUT=%i", loading_timeout))
+ return -ENOMEM;
+ if (add_uevent_var(env, "ASYNC=%d", fw_priv->nowait))
+ return -ENOMEM;
+
+ return 0;
+}
+
+static struct class firmware_class = {
+ .name = "firmware",
+ .class_attrs = firmware_class_attrs,
+ .dev_uevent = firmware_uevent,
+ .dev_release = fw_dev_release,
+};
+
+static ssize_t firmware_loading_show(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ struct firmware_priv *fw_priv = to_firmware_priv(dev);
+ int loading = 0;
+
+ mutex_lock(&fw_lock);
+ if (fw_priv->buf)
+ loading = test_bit(FW_STATUS_LOADING, &fw_priv->buf->status);
+ 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 fw_map_pages_buf(struct firmware_buf *buf)
+{
+ if (!buf->is_paged_buf)
+ return 0;
+
+ vunmap(buf->data);
+ buf->data = vmap(buf->pages, buf->nr_pages, 0, PAGE_KERNEL_RO);
+ if (!buf->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 firmware_priv *fw_priv = to_firmware_priv(dev);
+ struct firmware_buf *fw_buf;
+ ssize_t written = count;
+ int loading = simple_strtol(buf, NULL, 10);
+ int i;
+
+ mutex_lock(&fw_lock);
+ fw_buf = fw_priv->buf;
+ if (!fw_buf)
+ goto out;
+
+ switch (loading) {
+ case 1:
+ /* discarding any previous partial load */
+ if (!test_bit(FW_STATUS_DONE, &fw_buf->status)) {
+ for (i = 0; i < fw_buf->nr_pages; i++)
+ __free_page(fw_buf->pages[i]);
+ kfree(fw_buf->pages);
+ fw_buf->pages = NULL;
+ fw_buf->page_array_size = 0;
+ fw_buf->nr_pages = 0;
+ set_bit(FW_STATUS_LOADING, &fw_buf->status);
+ }
+ break;
+ case 0:
+ if (test_bit(FW_STATUS_LOADING, &fw_buf->status)) {
+ int rc;
+
+ set_bit(FW_STATUS_DONE, &fw_buf->status);
+ clear_bit(FW_STATUS_LOADING, &fw_buf->status);
+
+ /*
+ * 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 = fw_map_pages_buf(fw_buf);
+ if (rc)
+ dev_err(dev, "%s: map pages failed\n",
+ __func__);
+ else
+ rc = security_kernel_fw_from_file(NULL,
+ fw_buf->data, fw_buf->size);
+
+ /*
+ * Same logic as fw_load_abort, only the DONE bit
+ * is ignored and we set ABORT only on failure.
+ */
+ list_del_init(&fw_buf->pending_list);
+ if (rc) {
+ set_bit(FW_STATUS_ABORT, &fw_buf->status);
+ written = rc;
+ }
+ complete_all(&fw_buf->completion);
+ break;
+ }
+ /* fallthrough */
+ default:
+ dev_err(dev, "%s: unexpected value (%d)\n", __func__, loading);
+ /* fallthrough */
+ case -1:
+ fw_load_abort(fw_priv);
+ break;
+ }
+out:
+ mutex_unlock(&fw_lock);
+ return written;
+}
+
+static DEVICE_ATTR(loading, 0644, firmware_loading_show, firmware_loading_store);
+
+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 firmware_priv *fw_priv = to_firmware_priv(dev);
+ struct firmware_buf *buf;
+ ssize_t ret_count;
+
+ mutex_lock(&fw_lock);
+ buf = fw_priv->buf;
+ if (!buf || test_bit(FW_STATUS_DONE, &buf->status)) {
+ ret_count = -ENODEV;
+ goto out;
+ }
+ if (offset > buf->size) {
+ ret_count = 0;
+ goto out;
+ }
+ if (count > buf->size - offset)
+ count = buf->size - offset;
+
+ ret_count = count;
+
+ 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(buf->pages[page_nr]);
+
+ memcpy(buffer, page_data + page_ofs, page_cnt);
+
+ kunmap(buf->pages[page_nr]);
+ buffer += page_cnt;
+ offset += page_cnt;
+ count -= page_cnt;
+ }
+out:
+ mutex_unlock(&fw_lock);
+ return ret_count;
+}
+
+static int fw_realloc_buffer(struct firmware_priv *fw_priv, int min_size)
+{
+ struct firmware_buf *buf = fw_priv->buf;
+ int pages_needed = PAGE_ALIGN(min_size) >> PAGE_SHIFT;
+
+ /* If the array of pages is too small, grow it... */
+ if (buf->page_array_size < pages_needed) {
+ int new_array_size = max(pages_needed,
+ buf->page_array_size * 2);
+ struct page **new_pages;
+
+ new_pages = kmalloc(new_array_size * sizeof(void *),
+ GFP_KERNEL);
+ if (!new_pages) {
+ fw_load_abort(fw_priv);
+ return -ENOMEM;
+ }
+ memcpy(new_pages, buf->pages,
+ buf->page_array_size * sizeof(void *));
+ memset(&new_pages[buf->page_array_size], 0, sizeof(void *) *
+ (new_array_size - buf->page_array_size));
+ kfree(buf->pages);
+ buf->pages = new_pages;
+ buf->page_array_size = new_array_size;
+ }
+
+ while (buf->nr_pages < pages_needed) {
+ buf->pages[buf->nr_pages] =
+ alloc_page(GFP_KERNEL | __GFP_HIGHMEM);
+
+ if (!buf->pages[buf->nr_pages]) {
+ fw_load_abort(fw_priv);
+ return -ENOMEM;
+ }
+ buf->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 firmware_priv *fw_priv = to_firmware_priv(dev);
+ struct firmware_buf *buf;
+ ssize_t retval;
+
+ if (!capable(CAP_SYS_RAWIO))
+ return -EPERM;
+
+ mutex_lock(&fw_lock);
+ buf = fw_priv->buf;
+ if (!buf || test_bit(FW_STATUS_DONE, &buf->status)) {
+ retval = -ENODEV;
+ goto out;
+ }
+
+ retval = fw_realloc_buffer(fw_priv, offset + count);
+ if (retval)
+ goto out;
+
+ retval = count;
+
+ 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(buf->pages[page_nr]);
+
+ memcpy(page_data + page_ofs, buffer, page_cnt);
+
+ kunmap(buf->pages[page_nr]);
+ buffer += page_cnt;
+ offset += page_cnt;
+ count -= page_cnt;
+ }
+
+ buf->size = max_t(size_t, offset, buf->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 firmware_priv *
+fw_create_instance(struct firmware *firmware, const char *fw_name,
+ struct device *device, unsigned int opt_flags)
+{
+ struct firmware_priv *fw_priv;
+ struct device *f_dev;
+
+ fw_priv = kzalloc(sizeof(*fw_priv), GFP_KERNEL);
+ if (!fw_priv) {
+ fw_priv = ERR_PTR(-ENOMEM);
+ goto exit;
+ }
+
+ fw_priv->nowait = !!(opt_flags & FW_OPT_NOWAIT);
+ fw_priv->fw = firmware;
+ f_dev = &fw_priv->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_priv;
+}
+
+/* load a firmware via user helper */
+static int _request_firmware_load(struct firmware_priv *fw_priv,
+ unsigned int opt_flags, long timeout)
+{
+ int retval = 0;
+ struct device *f_dev = &fw_priv->dev;
+ struct firmware_buf *buf = fw_priv->buf;
+
+ /* fall back on userspace loading */
+ buf->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(&buf->pending_list, &pending_fw_head);
+ mutex_unlock(&fw_lock);
+
+ if (opt_flags & FW_OPT_UEVENT) {
+ buf->need_uevent = true;
+ dev_set_uevent_suppress(f_dev, false);
+ dev_dbg(f_dev, "firmware: requesting %s\n", buf->fw_id);
+ kobject_uevent(&fw_priv->dev.kobj, KOBJ_ADD);
+ } else {
+ timeout = MAX_JIFFY_OFFSET;
+ }
+
+ retval = wait_for_completion_interruptible_timeout(&buf->completion,
+ timeout);
+ if (retval == -ERESTARTSYS || !retval) {
+ mutex_lock(&fw_lock);
+ fw_load_abort(fw_priv);
+ mutex_unlock(&fw_lock);
+ } else if (retval > 0) {
+ retval = 0;
+ }
+
+ if (is_fw_load_aborted(buf))
+ retval = -EAGAIN;
+ else if (!buf->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, long timeout)
+{
+ struct firmware_priv *fw_priv;
+
+ fw_priv = fw_create_instance(firmware, name, device, opt_flags);
+ if (IS_ERR(fw_priv))
+ return PTR_ERR(fw_priv);
+
+ fw_priv->buf = firmware->priv;
+ return _request_firmware_load(fw_priv, opt_flags, timeout);
+}
+
+#ifdef CONFIG_PM_SLEEP
+/* kill pending requests without uevent to avoid blocking suspend */
+static void kill_requests_without_uevent(void)
+{
+ struct firmware_buf *buf;
+ struct firmware_buf *next;
+
+ mutex_lock(&fw_lock);
+ list_for_each_entry_safe(buf, next, &pending_fw_head, pending_list) {
+ if (!buf->need_uevent)
+ __fw_load_abort(buf);
+ }
+ mutex_unlock(&fw_lock);
+}
+#endif
+
+#else /* CONFIG_FW_LOADER_USER_HELPER */
+static inline int
+fw_load_from_user_helper(struct firmware *firmware, const char *name,
+ struct device *device, unsigned int opt_flags,
+ long timeout)
+{
+ return -ENOENT;
+}
+
+/* No abort during direct loading */
+#define is_fw_load_aborted(buf) false
+
+#ifdef CONFIG_PM_SLEEP
+static inline void kill_requests_without_uevent(void) { }
+#endif
+
+#endif /* CONFIG_FW_LOADER_USER_HELPER */
+
+
+/* wait until the shared firmware_buf becomes ready (or error) */
+static int sync_cached_firmware_buf(struct firmware_buf *buf)
+{
+ int ret = 0;
+
+ mutex_lock(&fw_lock);
+ while (!test_bit(FW_STATUS_DONE, &buf->status)) {
+ if (is_fw_load_aborted(buf)) {
+ ret = -ENOENT;
+ break;
+ }
+ mutex_unlock(&fw_lock);
+ ret = wait_for_completion_interruptible(&buf->completion);
+ mutex_lock(&fw_lock);
+ }
+ mutex_unlock(&fw_lock);
+ return ret;
+}
+
+/* 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)
+{
+ struct firmware *firmware;
+ struct firmware_buf *buf;
+ 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)) {
+ dev_dbg(device, "firmware: using built-in firmware %s\n", name);
+ return 0; /* assigned */
+ }
+
+ ret = fw_lookup_and_allocate_buf(name, &fw_cache, &buf);
+
+ /*
+ * bind with 'buf' now to avoid warning in failure path
+ * of requesting firmware.
+ */
+ firmware->priv = buf;
+
+ if (ret > 0) {
+ ret = sync_cached_firmware_buf(buf);
+ if (!ret) {
+ fw_set_page_data(buf, firmware);
+ return 0; /* assigned */
+ }
+ }
+
+ if (ret < 0)
+ return ret;
+ return 1; /* need to load */
+}
+
+static int assign_firmware_buf(struct firmware *fw, struct device *device,
+ unsigned int opt_flags)
+{
+ struct firmware_buf *buf = fw->priv;
+
+ mutex_lock(&fw_lock);
+ if (!buf->size || is_fw_load_aborted(buf)) {
+ 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))
+ fw_add_devm_name(device, buf->fw_id);
+
+ /*
+ * After caching firmware image is started, let it piggyback
+ * on request firmware.
+ */
+ if (buf->fwc->state == FW_LOADER_START_CACHE) {
+ if (fw_cache_piggyback_on_request(buf->fw_id))
+ kref_get(&buf->ref);
+ }
+
+ /* pass the pages buffer to driver at the last minute */
+ fw_set_page_data(buf, fw);
+ mutex_unlock(&fw_lock);
+ return 0;
+}
+
+/* called from request_firmware() and request_firmware_work_func() */
+static int
+_request_firmware(const struct firmware **firmware_p, const char *name,
+ struct device *device, unsigned int opt_flags)
+{
+ struct firmware *fw;
+ long timeout;
+ int ret;
+
+ if (!firmware_p)
+ return -EINVAL;
+
+ if (!name || name[0] == '\0')
+ return -EINVAL;
+
+ ret = _request_firmware_prepare(&fw, name, device);
+ if (ret <= 0) /* error or already assigned */
+ goto out;
+
+ ret = 0;
+ 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);
+ ret = -EBUSY;
+ goto out;
+ }
+ } else {
+ ret = usermodehelper_read_trylock();
+ if (WARN_ON(ret)) {
+ dev_err(device, "firmware: %s will not be loaded\n",
+ name);
+ 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);
+ if (opt_flags & FW_OPT_USERHELPER) {
+ dev_warn(device, "Falling back to user helper\n");
+ ret = fw_load_from_user_helper(fw, name, device,
+ opt_flags, timeout);
+ }
+ }
+
+ if (!ret)
+ ret = assign_firmware_buf(fw, device, opt_flags);
+
+ usermodehelper_read_unlock();
+
+ out:
+ if (ret < 0) {
+ 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,
+ FW_OPT_UEVENT | FW_OPT_FALLBACK);
+ 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,
+ FW_OPT_UEVENT | FW_OPT_NO_WARN);
+ module_put(THIS_MODULE);
+ return ret;
+}
+EXPORT_SYMBOL_GPL(request_firmware_direct);
+
+/**
+ * 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,
+ 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(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 = name;
+ fw_work->device = device;
+ fw_work->context = context;
+ fw_work->cont = cont;
+ fw_work->opt_flags = FW_OPT_NOWAIT | FW_OPT_FALLBACK |
+ (uevent ? FW_OPT_UEVENT : FW_OPT_USERHELPER);
+
+ if (!try_module_get(module)) {
+ 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 firmware_buf *fw_lookup_buf(const char *fw_name)
+{
+ struct firmware_buf *tmp;
+ struct firmware_cache *fwc = &fw_cache;
+
+ spin_lock(&fwc->lock);
+ tmp = __fw_lookup_buf(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 firmware_buf *buf;
+ struct firmware fw;
+
+ pr_debug("%s: %s\n", __func__, fw_name);
+
+ if (fw_get_builtin_firmware(&fw, fw_name))
+ return 0;
+
+ buf = fw_lookup_buf(fw_name);
+ if (buf) {
+ fw_free_buf(buf);
+ 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) + strlen(name) + 1, GFP_ATOMIC);
+ if (!fce)
+ goto exit;
+
+ strcpy(fce->name, name);
+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(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;
+ int old_timeout;
+ DEFINE_WAIT(wait);
+
+ pr_debug("%s\n", __func__);
+
+ /* cancel uncache work */
+ cancel_delayed_work_sync(&fwc->work);
+
+ /*
+ * 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.
+ */
+ old_timeout = loading_timeout;
+ loading_timeout = 10;
+
+ 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);
+
+ loading_timeout = old_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_requests_without_uevent();
+ 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,
+};
+#else
+static int fw_cache_piggyback_on_request(const char *name)
+{
+ return 0;
+}
+#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;
+
+#ifdef CONFIG_PM_SLEEP
+ 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;
+ register_pm_notifier(&fw_cache.pm_notify);
+
+ register_syscore_ops(&fw_syscore_ops);
+#endif
+}
+
+static int __init firmware_class_init(void)
+{
+ fw_cache_init();
+#ifdef CONFIG_FW_LOADER_USER_HELPER
+ register_reboot_notifier(&fw_shutdown_nb);
+ return class_register(&firmware_class);
+#else
+ return 0;
+#endif
+}
+
+static void __exit firmware_class_exit(void)
+{
+#ifdef CONFIG_PM_SLEEP
+ unregister_syscore_ops(&fw_syscore_ops);
+ unregister_pm_notifier(&fw_cache.pm_notify);
+#endif
+#ifdef CONFIG_FW_LOADER_USER_HELPER
+ unregister_reboot_notifier(&fw_shutdown_nb);
+ class_unregister(&firmware_class);
+#endif
+}
+
+fs_initcall(firmware_class_init);
+module_exit(firmware_class_exit);