* guarding for corner cases a global lock should be OK */
static DEFINE_MUTEX(fw_lock);
-static bool __enable_firmware = false;
-
-static void enable_firmware(void)
-{
- mutex_lock(&fw_lock);
- __enable_firmware = true;
- mutex_unlock(&fw_lock);
-}
-
-static void disable_firmware(void)
-{
- mutex_lock(&fw_lock);
- __enable_firmware = false;
- mutex_unlock(&fw_lock);
-}
-
-/*
- * When disabled only the built-in firmware and the firmware cache will be
- * used to look for firmware.
- */
-static bool firmware_enabled(void)
-{
- bool enabled = false;
-
- mutex_lock(&fw_lock);
- if (__enable_firmware)
- enabled = true;
- mutex_unlock(&fw_lock);
-
- return enabled;
-}
-
static struct firmware_cache fw_cache;
static struct firmware_buf *__allocate_fw_buf(const char *fw_name,
if (ret <= 0) /* error or already assigned */
goto out;
- if (!firmware_enabled()) {
- WARN(1, "firmware request while host is not available\n");
- ret = -EHOSTDOWN;
- goto out;
- }
-
ret = fw_get_filesystem_firmware(device, fw->priv);
if (ret) {
if (!(opt_flags & FW_OPT_NO_WARN))
msecs_to_jiffies(delay));
}
-/**
- * fw_pm_notify - notifier for suspend/resume
- * @notify_block: unused
- * @mode: mode we are switching to
- * @unused: unused
- *
- * Used to modify the firmware_class state as we move in between states.
- * The firmware_class implements a firmware cache to enable device driver
- * to fetch firmware upon resume before the root filesystem is ready. We
- * disable API calls which do not use the built-in firmware or the firmware
- * cache when we know these calls will not work.
- *
- * The inner logic behind all this is a bit complex so it is worth summarizing
- * the kernel's own suspend/resume process with context and focus on how this
- * can impact the firmware API.
- *
- * First a review on how we go to suspend::
- *
- * pm_suspend() --> enter_state() -->
- * sys_sync()
- * suspend_prepare() -->
- * __pm_notifier_call_chain(PM_SUSPEND_PREPARE, ...);
- * suspend_freeze_processes() -->
- * freeze_processes() -->
- * __usermodehelper_set_disable_depth(UMH_DISABLED);
- * freeze all tasks ...
- * freeze_kernel_threads()
- * suspend_devices_and_enter() -->
- * dpm_suspend_start() -->
- * dpm_prepare()
- * dpm_suspend()
- * suspend_enter() -->
- * platform_suspend_prepare()
- * dpm_suspend_late()
- * freeze_enter()
- * syscore_suspend()
- *
- * When we resume we bail out of a loop from suspend_devices_and_enter() and
- * unwind back out to the caller enter_state() where we were before as follows::
- *
- * enter_state() -->
- * suspend_devices_and_enter() --> (bail from loop)
- * dpm_resume_end() -->
- * dpm_resume()
- * dpm_complete()
- * suspend_finish() -->
- * suspend_thaw_processes() -->
- * thaw_processes() -->
- * __usermodehelper_set_disable_depth(UMH_FREEZING);
- * thaw_workqueues();
- * thaw all processes ...
- * usermodehelper_enable();
- * pm_notifier_call_chain(PM_POST_SUSPEND);
- *
- * fw_pm_notify() works through pm_notifier_call_chain().
- */
static int fw_pm_notify(struct notifier_block *notify_block,
unsigned long mode, void *unused)
{
*/
kill_pending_fw_fallback_reqs(true);
device_cache_fw_images();
- disable_firmware();
break;
case PM_POST_SUSPEND:
mutex_lock(&fw_lock);
fw_cache.state = FW_LOADER_NO_CACHE;
mutex_unlock(&fw_lock);
- enable_firmware();
device_uncache_fw_images_delay(10 * MSEC_PER_SEC);
break;
static int fw_shutdown_notify(struct notifier_block *unused1,
unsigned long unused2, void *unused3)
{
- disable_firmware();
/*
* Kill all pending fallback requests to avoid both stalling shutdown,
* and avoid a deadlock with the usermode_lock.
static int __init firmware_class_init(void)
{
- enable_firmware();
fw_cache_init();
register_reboot_notifier(&fw_shutdown_nb);
#ifdef CONFIG_FW_LOADER_USER_HELPER
static void __exit firmware_class_exit(void)
{
- disable_firmware();
#ifdef CONFIG_PM_SLEEP
unregister_syscore_ops(&fw_syscore_ops);
unregister_pm_notifier(&fw_cache.pm_notify);