kernel-fxtec-pro1x/drivers/base/firmware_class.c
Ming Lei 07646d9c09 firmware loader: cache devices firmware during suspend/resume cycle
This patch implements caching devices' firmware automatically
during system syspend/resume cycle, so any device drivers can
call request_firmware or request_firmware_nowait inside resume
path to get the cached firmware if they have loaded firmwares
successfully at least once before entering suspend.

Signed-off-by: Ming Lei <ming.lei@canonical.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-08-16 13:44:44 -07:00

1284 lines
30 KiB
C

/*
* 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/list.h>
#include <linux/async.h>
#include <linux/pm.h>
#include <linux/suspend.h>
#include "base.h"
#include "power/power.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_SCHEDULE_TIMEOUT;
}
struct firmware_cache {
/* firmware_buf instance will be added into the below list */
spinlock_t lock;
struct list_head head;
/*
* 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;
wait_queue_head_t wait_queue;
int cnt;
struct delayed_work work;
struct notifier_block pm_notify;
};
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;
struct page **pages;
int nr_pages;
int page_array_size;
char fw_id[];
};
struct fw_cache_entry {
struct list_head list;
char name[];
};
struct firmware_priv {
struct timer_list timeout;
bool nowait;
struct device dev;
struct firmware_buf *buf;
struct firmware *fw;
};
struct fw_name_devm {
unsigned long magic;
char name[];
};
#define to_fwbuf(d) container_of(d, struct firmware_buf, ref)
/* 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);
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 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;
}
static void __fw_free_buf(struct kref *ref)
{
struct firmware_buf *buf = to_fwbuf(ref);
struct firmware_cache *fwc = buf->fwc;
int i;
pr_debug("%s: fw-%s buf=%p data=%p size=%u\n",
__func__, buf->fw_id, buf, buf->data,
(unsigned int)buf->size);
spin_lock(&fwc->lock);
list_del(&buf->list);
spin_unlock(&fwc->lock);
vunmap(buf->data);
for (i = 0; i < buf->nr_pages; i++)
__free_page(buf->pages[i]);
kfree(buf->pages);
kfree(buf);
}
static void fw_free_buf(struct firmware_buf *buf)
{
kref_put(&buf->ref, __fw_free_buf);
}
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_priv *fw_priv)
{
struct firmware_buf *buf = fw_priv->buf;
set_bit(FW_STATUS_ABORT, &buf->status);
complete_all(&buf->completion);
}
static ssize_t firmware_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 firmware_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(timeout, S_IWUSR | S_IRUGO,
firmware_timeout_show, firmware_timeout_store),
__ATTR_NULL
};
static void fw_dev_release(struct device *dev)
{
struct firmware_priv *fw_priv = to_firmware_priv(dev);
kfree(fw_priv);
module_put(THIS_MODULE);
}
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 = test_bit(FW_STATUS_LOADING, &fw_priv->buf->status);
return sprintf(buf, "%d\n", loading);
}
/* firmware holds the ownership of pages */
static void firmware_free_data(const struct firmware *fw)
{
WARN_ON(!fw->priv);
fw_free_buf(fw->priv);
}
/* Some architectures don't have PAGE_KERNEL_RO */
#ifndef PAGE_KERNEL_RO
#define PAGE_KERNEL_RO PAGE_KERNEL
#endif
/**
* 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 = fw_priv->buf;
int loading = simple_strtol(buf, NULL, 10);
int i;
mutex_lock(&fw_lock);
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)) {
set_bit(FW_STATUS_DONE, &fw_buf->status);
clear_bit(FW_STATUS_LOADING, &fw_buf->status);
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 count;
}
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 = ALIGN(min_size, PAGE_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 void firmware_class_timeout(u_long data)
{
struct firmware_priv *fw_priv = (struct firmware_priv *) data;
fw_load_abort(fw_priv);
}
static struct firmware_priv *
fw_create_instance(struct firmware *firmware, const char *fw_name,
struct device *device, bool uevent, bool nowait)
{
struct firmware_priv *fw_priv;
struct device *f_dev;
fw_priv = kzalloc(sizeof(*fw_priv), GFP_KERNEL);
if (!fw_priv) {
dev_err(device, "%s: kmalloc failed\n", __func__);
fw_priv = ERR_PTR(-ENOMEM);
goto exit;
}
fw_priv->nowait = nowait;
fw_priv->fw = firmware;
setup_timer(&fw_priv->timeout,
firmware_class_timeout, (u_long) fw_priv);
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;
exit:
return fw_priv;
}
/* one pages buffer is mapped/unmapped only once */
static int fw_map_pages_buf(struct firmware_buf *buf)
{
buf->data = vmap(buf->pages, buf->nr_pages, 0, PAGE_KERNEL_RO);
if (!buf->data)
return -ENOMEM;
return 0;
}
/* store the pages buffer info firmware from buf */
static void fw_set_page_data(struct firmware_buf *buf, struct firmware *fw)
{
fw->priv = buf;
fw->pages = buf->pages;
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);
}
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;
}
static void _request_firmware_cleanup(const struct firmware **firmware_p)
{
release_firmware(*firmware_p);
*firmware_p = NULL;
}
static struct firmware_priv *
_request_firmware_prepare(const struct firmware **firmware_p, const char *name,
struct device *device, bool uevent, bool nowait)
{
struct firmware *firmware;
struct firmware_priv *fw_priv = NULL;
struct firmware_buf *buf;
int ret;
if (!firmware_p)
return ERR_PTR(-EINVAL);
*firmware_p = firmware = kzalloc(sizeof(*firmware), GFP_KERNEL);
if (!firmware) {
dev_err(device, "%s: kmalloc(struct firmware) failed\n",
__func__);
return ERR_PTR(-ENOMEM);
}
if (fw_get_builtin_firmware(firmware, name)) {
dev_dbg(device, "firmware: using built-in firmware %s\n", name);
return NULL;
}
ret = fw_lookup_and_allocate_buf(name, &fw_cache, &buf);
if (!ret)
fw_priv = fw_create_instance(firmware, name, device,
uevent, nowait);
if (IS_ERR(fw_priv) || ret < 0) {
kfree(firmware);
*firmware_p = NULL;
return ERR_PTR(-ENOMEM);
} else if (fw_priv) {
fw_priv->buf = buf;
/*
* bind with 'buf' now to avoid warning in failure path
* of requesting firmware.
*/
firmware->priv = buf;
return fw_priv;
}
/* share the cached buf, which is inprogessing or completed */
check_status:
mutex_lock(&fw_lock);
if (test_bit(FW_STATUS_ABORT, &buf->status)) {
fw_priv = ERR_PTR(-ENOENT);
_request_firmware_cleanup(firmware_p);
goto exit;
} else if (test_bit(FW_STATUS_DONE, &buf->status)) {
fw_priv = NULL;
fw_set_page_data(buf, firmware);
goto exit;
}
mutex_unlock(&fw_lock);
wait_for_completion(&buf->completion);
goto check_status;
exit:
mutex_unlock(&fw_lock);
return fw_priv;
}
static int _request_firmware_load(struct firmware_priv *fw_priv, bool uevent,
long timeout)
{
int retval = 0;
struct device *f_dev = &fw_priv->dev;
struct firmware_buf *buf = fw_priv->buf;
dev_set_uevent_suppress(f_dev, true);
/* Need to pin this module until class device is destroyed */
__module_get(THIS_MODULE);
retval = device_add(f_dev);
if (retval) {
dev_err(f_dev, "%s: device_register failed\n", __func__);
goto err_put_dev;
}
retval = device_create_bin_file(f_dev, &firmware_attr_data);
if (retval) {
dev_err(f_dev, "%s: sysfs_create_bin_file failed\n", __func__);
goto err_del_dev;
}
retval = device_create_file(f_dev, &dev_attr_loading);
if (retval) {
dev_err(f_dev, "%s: device_create_file failed\n", __func__);
goto err_del_bin_attr;
}
if (uevent) {
dev_set_uevent_suppress(f_dev, false);
dev_dbg(f_dev, "firmware: requesting %s\n", buf->fw_id);
if (timeout != MAX_SCHEDULE_TIMEOUT)
mod_timer(&fw_priv->timeout,
round_jiffies_up(jiffies + timeout));
kobject_uevent(&fw_priv->dev.kobj, KOBJ_ADD);
}
wait_for_completion(&buf->completion);
del_timer_sync(&fw_priv->timeout);
mutex_lock(&fw_lock);
if (!buf->size || test_bit(FW_STATUS_ABORT, &buf->status))
retval = -ENOENT;
/*
* add firmware name into devres list so that we can auto cache
* and uncache firmware for device.
*
* f_dev->parent may has been deleted already, but the problem
* should be fixed in devres or driver core.
*/
if (!retval && f_dev->parent)
fw_add_devm_name(f_dev->parent, buf->fw_id);
if (!retval)
retval = fw_map_pages_buf(buf);
/* pass the pages buffer to driver at the last minute */
fw_set_page_data(buf, fw_priv->fw);
fw_priv->buf = NULL;
mutex_unlock(&fw_lock);
device_remove_file(f_dev, &dev_attr_loading);
err_del_bin_attr:
device_remove_bin_file(f_dev, &firmware_attr_data);
err_del_dev:
device_del(f_dev);
err_put_dev:
put_device(f_dev);
return retval;
}
/**
* 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.
**/
int
request_firmware(const struct firmware **firmware_p, const char *name,
struct device *device)
{
struct firmware_priv *fw_priv;
int ret;
fw_priv = _request_firmware_prepare(firmware_p, name, device, true,
false);
if (IS_ERR_OR_NULL(fw_priv))
return PTR_RET(fw_priv);
ret = usermodehelper_read_trylock();
if (WARN_ON(ret)) {
dev_err(device, "firmware: %s will not be loaded\n", name);
} else {
ret = _request_firmware_load(fw_priv, true,
firmware_loading_timeout());
usermodehelper_read_unlock();
}
if (ret)
_request_firmware_cleanup(firmware_p);
return ret;
}
/**
* 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);
}
}
/* 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);
bool uevent;
};
static void request_firmware_work_func(struct work_struct *work)
{
struct firmware_work *fw_work;
const struct firmware *fw;
struct firmware_priv *fw_priv;
long timeout;
int ret;
fw_work = container_of(work, struct firmware_work, work);
fw_priv = _request_firmware_prepare(&fw, fw_work->name, fw_work->device,
fw_work->uevent, true);
if (IS_ERR_OR_NULL(fw_priv)) {
ret = PTR_RET(fw_priv);
goto out;
}
timeout = usermodehelper_read_lock_wait(firmware_loading_timeout());
if (timeout) {
ret = _request_firmware_load(fw_priv, fw_work->uevent, timeout);
usermodehelper_read_unlock();
} else {
dev_dbg(fw_work->device, "firmware: %s loading timed out\n",
fw_work->name);
ret = -EAGAIN;
}
if (ret)
_request_firmware_cleanup(&fw);
out:
fw_work->cont(fw, fw_work->context);
put_device(fw_work->device);
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->uevent = uevent;
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;
}
/**
* 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
*
*/
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;
}
/**
* 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
*
*/
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 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)
goto free;
spin_lock(&fwc->name_lock);
list_add(&fce->list, &fwc->fw_names);
spin_unlock(&fwc->name_lock);
goto drop_ref;
free:
free_fw_cache_entry(fce);
drop_ref:
spin_lock(&fwc->name_lock);
fwc->cnt--;
spin_unlock(&fwc->name_lock);
wake_up(&fwc->wait_queue);
}
/* 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)
{
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);
fwc->cnt++;
spin_unlock(&fwc->name_lock);
async_schedule(__async_dev_cache_fw_image, (void *)fce);
}
}
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;
struct device *dev;
int old_timeout;
DEFINE_WAIT(wait);
pr_debug("%s\n", __func__);
/*
* 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;
device_pm_lock();
list_for_each_entry(dev, &dpm_list, power.entry)
dev_cache_fw_image(dev);
device_pm_unlock();
/* wait for completion of caching firmware for all devices */
spin_lock(&fwc->name_lock);
for (;;) {
prepare_to_wait(&fwc->wait_queue, &wait,
TASK_UNINTERRUPTIBLE);
if (!fwc->cnt)
break;
spin_unlock(&fwc->name_lock);
schedule();
spin_lock(&fwc->name_lock);
}
spin_unlock(&fwc->name_lock);
finish_wait(&fwc->wait_queue, &wait);
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)
{
schedule_delayed_work(&fw_cache.work,
msecs_to_jiffies(delay));
}
#ifdef CONFIG_PM
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:
device_cache_fw_images();
break;
case PM_POST_SUSPEND:
case PM_POST_HIBERNATION:
case PM_POST_RESTORE:
device_uncache_fw_images_delay(10 * MSEC_PER_SEC);
break;
}
return 0;
}
#else
static int fw_pm_notify(struct notifier_block *notify_block,
unsigned long mode, void *unused)
{}
#endif
static void __init fw_cache_init(void)
{
spin_lock_init(&fw_cache.lock);
INIT_LIST_HEAD(&fw_cache.head);
spin_lock_init(&fw_cache.name_lock);
INIT_LIST_HEAD(&fw_cache.fw_names);
fw_cache.cnt = 0;
init_waitqueue_head(&fw_cache.wait_queue);
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);
}
static int __init firmware_class_init(void)
{
fw_cache_init();
return class_register(&firmware_class);
}
static void __exit firmware_class_exit(void)
{
unregister_pm_notifier(&fw_cache.pm_notify);
class_unregister(&firmware_class);
}
fs_initcall(firmware_class_init);
module_exit(firmware_class_exit);
EXPORT_SYMBOL(release_firmware);
EXPORT_SYMBOL(request_firmware);
EXPORT_SYMBOL(request_firmware_nowait);
EXPORT_SYMBOL_GPL(cache_firmware);
EXPORT_SYMBOL_GPL(uncache_firmware);