linux.git/drivers/base/firmware_class.c, branch v3.7-rc2

firmware: use 'kernel_read()' to read firmware into kernel buffer

2012-10-04T16:19:02+00:00

Fengguang correctly points out that the firmware reading should not use
vfs_read(), since the buffer is in kernel space.

The vfs_read() just happened to work for kernel threads, but sparse
warns about the incorrect address spaces, and it's definitely incorrect
and could fail for other users of the firmware loading.

Reported-by: Fengguang Wu 
Signed-off-by: Linus Torvalds

firmware: teach the kernel to load firmware files directly from the filesystem

2012-10-03T22:58:32+00:00

This is a first step in allowing people to by-pass udev for loading
device firmware.  Current versions of udev will deadlock (causing us to
block for the 30 second timeout) under some circumstances if the
firmware is loaded as part of the module initialization path, and this
is causing problems for media drivers in particular.

The current patch hardcodes the firmware path that udev uses by default,
and will fall back to the legacy udev mode if the firmware cannot be
found there.  We'd like to add support for both configuring the paths
and the fallback behaviour, but in the meantime this hopefully fixes the
immediate problem, while also giving us a way forward.

[ v2: Some VFS layer interface cleanups suggested by Al Viro ]
[ v3: use the default udev paths suggested by Kay Sievers ]

Suggested-by: Ivan Kalvachev 
Acked-by: Greg KH 
Acked-by: Al Viro 
Cc: Mauro Carvalho Chehab 
Cc: Kay Sievers 
Cc: Ming Lei 
Signed-off-by: Linus Torvalds

firmware loader: fix compile warning when CONFIG_PM=n

2012-09-10T23:40:30+00:00

This patch replaces the previous macro of CONFIG_PM with
CONFIG_PM_SLEEP becasue firmware cache is only used in
system sleep situations.

Also this patch fixes the below compile warning when
CONFIG_PM=n:

	drivers/base/firmware_class.c:1147: warning: 'device_cache_fw_images'
	defined but not used
	drivers/base/firmware_class.c:1212: warning:
	'device_uncache_fw_images_delay' defined but not used

Reported-by: Andrew Morton 
Signed-off-by: Ming Lei 
Signed-off-by: Greg Kroah-Hartman

firmware loader: let caching firmware piggyback on loading firmware

2012-09-06T21:46:16+00:00

After starting caching firmware, there is still some time left
before devices are suspended, during the period, request_firmware
or its nowait version may still be triggered by the below situations
to load firmware images which can't be cached during suspend/resume
cycle.

	- new devices added
	- driver bind
	- or device open kind of things

This patch utilizes the piggyback trick to cache firmware for
this kind of situation: just increase the firmware buf's reference
count and add the fw name entry into cache entry list after starting
caching firmware and before syscore_suspend() is called.

Signed-off-by: Ming Lei 
Signed-off-by: Greg Kroah-Hartman

firmware loader: fix firmware -ENOENT situations

2012-09-06T21:46:16+00:00

If the requested firmware image doesn't exist, firmware->priv
should be set for the later concurrent requests, otherwise
warning and oops will be triggered inside firmware_free_data().

Signed-off-by: Ming Lei 
Signed-off-by: Greg Kroah-Hartman

firmware loader: fix build failure if FW_LOADER is m

2012-08-17T14:37:35+00:00

device_cache_fw_images need to iterate devices in system,
so this patch applies the introduced dpm_for_each_dev to
avoid link failure if CONFIG_FW_LOADER is m.

Reported-by: Fengguang Wu 
Signed-off-by: Ming Lei 
Signed-off-by: Greg Kroah-Hartman

firmware loader: fix compile failure if !PM

2012-08-17T14:36:11+00:00

'return 0' should be added to fw_pm_notify if !PM because
return value of the funcion is defined as 'int'.

Reported-by: Fengguang Wu 
Signed-off-by: Ming Lei 
Signed-off-by: Greg Kroah-Hartman

firmware loader: cache devices firmware during suspend/resume cycle

2012-08-16T20:44:44+00:00

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 
Cc: Linus Torvalds 
Signed-off-by: Greg Kroah-Hartman

firmware loader: use small timeout for cache device firmware

2012-08-16T20:44:44+00:00

Because device_cache_fw_images only cache the firmware which has been
loaded sucessfully at leat once, using a small loading timeout should
be reasonable.

Signed-off-by: Ming Lei 
Cc: Linus Torvalds 
Signed-off-by: Greg Kroah-Hartman

firmware: introduce device_cache/uncache_fw_images

2012-08-16T20:44:44+00:00

This patch introduces the three helpers below:

	void device_cache_fw_images(void)
	void device_uncache_fw_images(void)
	void device_uncache_fw_images_delay(unsigned long)

so we can use device_cache_fw_images() to cache firmware for
all devices which need firmware to work, and the device driver
can get the firmware easily from kernel memory when system isn't
ready for completing requests of loading firmware.

After system is ready for completing firmware loading, driver core
will call device_uncache_fw_images() or its delay version to free
the cached firmware.

The above helpers will be used to cache device firmware during
system suspend/resume cycle in the following patches.

Signed-off-by: Ming Lei 
Cc: Linus Torvalds 
Signed-off-by: Greg Kroah-Hartman