sparse warnings: (new ones prefixed by >>)

>> drivers/media/usb/em28xx/em28xx-video.c:1151:28: sparse: symbol 'em28xx_ctrl_ops' was not declared. Should it be static?
Signed-off-by: NFengguang Wu <fengguang.wu@intel.com>
Signed-off-by: NMauro Carvalho Chehab <m.chehab@samsung.com>

If something bad happens during init, we free the card data.
However, we still keep it initialized, causing some dependent
code to be called at .fini.

Fix it.
Signed-off-by: NMauro Carvalho Chehab <m.chehab@samsung.com>

As a pending action might be still there at the work
thread, flush it.
Signed-off-by: NMauro Carvalho Chehab <m.chehab@samsung.com>

The option to load firmware asynchronously were added due to
a requirement with a few versions of udev. It turns that this was
a bad idea and caused regressions on drxk-based devices.

So, we end by only letting the firmware to be loaded syncronously
everywhere.

So, let's remove the bad code.

This patch partially reverts the changeset 8e30783b.
Signed-off-by: NMauro Carvalho Chehab <m.chehab@samsung.com>

While the current hardcoded period is ok for the current values,
we may latter change the driver to work with different bit rates
or with different latencies than 64ms.

So, adust the period size at runtime.
Signed-off-by: NMauro Carvalho Chehab <m.chehab@samsung.com>

Avoid circular mutex lock by pushing the dev->lock to the .fini
callback on each extension.

As em28xx-dvb, em28xx-alsa and em28xx-rc have their own data
structures, and don't touch at the common structure during .fini,
only em28xx-v4l needs to be locked.

[   90.994317] ======================================================
[   90.994356] [ INFO: possible circular locking dependency detected ]
[   90.994395] 3.13.0-rc1+ #24 Not tainted
[   90.994427] -------------------------------------------------------
[   90.994458] khubd/54 is trying to acquire lock:
[   90.994490]  (&card->controls_rwsem){++++.+}, at: [<ffffffffa0177b08>] snd_ctl_dev_free+0x28/0x60 [snd]
[   90.994656]
[   90.994656] but task is already holding lock:
[   90.994688]  (&dev->lock){+.+.+.}, at: [<ffffffffa040db81>] em28xx_close_extension+0x31/0x90 [em28xx]
[   90.994843]
[   90.994843] which lock already depends on the new lock.
[   90.994843]
[   90.994874]
[   90.994874] the existing dependency chain (in reverse order) is:
[   90.994905]
-> #1 (&dev->lock){+.+.+.}:
[   90.995057]        [<ffffffff810b8fa3>] __lock_acquire+0xb43/0x1330
[   90.995121]        [<ffffffff810b9f82>] lock_acquire+0xa2/0x120
[   90.995182]        [<ffffffff816a5b6c>] mutex_lock_nested+0x5c/0x3c0
[   90.995245]        [<ffffffffa0422cca>] em28xx_vol_put_mute+0x1ba/0x1d0 [em28xx_alsa]
[   90.995309]        [<ffffffffa017813d>] snd_ctl_elem_write+0xfd/0x140 [snd]
[   90.995376]        [<ffffffffa01791c2>] snd_ctl_ioctl+0xe2/0x810 [snd]
[   90.995442]        [<ffffffff811db8b0>] do_vfs_ioctl+0x300/0x520
[   90.995504]        [<ffffffff811dbb51>] SyS_ioctl+0x81/0xa0
[   90.995568]        [<ffffffff816b1929>] system_call_fastpath+0x16/0x1b
[   90.995630]
-> #0 (&card->controls_rwsem){++++.+}:
[   90.995780]        [<ffffffff810b7a47>] check_prevs_add+0x947/0x950
[   90.995841]        [<ffffffff810b8fa3>] __lock_acquire+0xb43/0x1330
[   90.995901]        [<ffffffff810b9f82>] lock_acquire+0xa2/0x120
[   90.995962]        [<ffffffff816a762b>] down_write+0x3b/0xa0
[   90.996022]        [<ffffffffa0177b08>] snd_ctl_dev_free+0x28/0x60 [snd]
[   90.996088]        [<ffffffffa017a255>] snd_device_free+0x65/0x140 [snd]
[   90.996154]        [<ffffffffa017a751>] snd_device_free_all+0x61/0xa0 [snd]
[   90.996219]        [<ffffffffa0173af4>] snd_card_do_free+0x14/0x130 [snd]
[   90.996283]        [<ffffffffa0173f14>] snd_card_free+0x84/0x90 [snd]
[   90.996349]        [<ffffffffa0423397>] em28xx_audio_fini+0x97/0xb0 [em28xx_alsa]
[   90.996411]        [<ffffffffa040dba6>] em28xx_close_extension+0x56/0x90 [em28xx]
[   90.996475]        [<ffffffffa040f639>] em28xx_usb_disconnect+0x79/0x90 [em28xx]
[   90.996539]        [<ffffffff814a06e7>] usb_unbind_interface+0x67/0x1d0
[   90.996620]        [<ffffffff8142920f>] __device_release_driver+0x7f/0xf0
[   90.996682]        [<ffffffff814292a5>] device_release_driver+0x25/0x40
[   90.996742]        [<ffffffff81428b0c>] bus_remove_device+0x11c/0x1a0
[   90.996801]        [<ffffffff81425536>] device_del+0x136/0x1d0
[   90.996863]        [<ffffffff8149e0c0>] usb_disable_device+0xb0/0x290
[   90.996923]        [<ffffffff814930c5>] usb_disconnect+0xb5/0x1d0
[   90.996984]        [<ffffffff81495ab6>] hub_port_connect_change+0xd6/0xad0
[   90.997044]        [<ffffffff814967c3>] hub_events+0x313/0x9b0
[   90.997105]        [<ffffffff81496e95>] hub_thread+0x35/0x170
[   90.997165]        [<ffffffff8108ea2f>] kthread+0xff/0x120
[   90.997226]        [<ffffffff816b187c>] ret_from_fork+0x7c/0xb0
[   90.997287]
[   90.997287] other info that might help us debug this:
[   90.997287]
[   90.997318]  Possible unsafe locking scenario:
[   90.997318]
[   90.997348]        CPU0                    CPU1
[   90.997378]        ----                    ----
[   90.997408]   lock(&dev->lock);
[   90.997497]                                lock(&card->controls_rwsem);
[   90.997607]                                lock(&dev->lock);
[   90.997697]   lock(&card->controls_rwsem);
[   90.997786]
[   90.997786]  *** DEADLOCK ***
[   90.997786]
[   90.997817] 5 locks held by khubd/54:
[   90.997847]  #0:  (&__lockdep_no_validate__){......}, at: [<ffffffff81496564>] hub_events+0xb4/0x9b0
[   90.998025]  #1:  (&__lockdep_no_validate__){......}, at: [<ffffffff81493076>] usb_disconnect+0x66/0x1d0
[   90.998204]  #2:  (&__lockdep_no_validate__){......}, at: [<ffffffff8142929d>] device_release_driver+0x1d/0x40
[   90.998383]  #3:  (em28xx_devlist_mutex){+.+.+.}, at: [<ffffffffa040db77>] em28xx_close_extension+0x27/0x90 [em28xx]
[   90.998567]  #4:  (&dev->lock){+.+.+.}, at: [<ffffffffa040db81>] em28xx_close_extension+0x31/0x90 [em28xx]
Reviewed-by: NFrank Schäfer <fschaefer.oss@googlemail.com>
Tested-by: NAntti Palosaari <crope@iki.fi>
Signed-off-by: NMauro Carvalho Chehab <m.chehab@samsung.com>

Now that everything is extension, the usb disconnect logic should
be the same.

While here, fix the device name.
Reviewed-by: NFrank Schäfer <fschaefer.oss@googlemail.com>
Tested-by: NAntti Palosaari <crope@iki.fi>
Signed-off-by: NMauro Carvalho Chehab <m.chehab@samsung.com>

That helps to identify if something fails and explain why em28xx
struct is not freed (if it ever happens).
Reviewed-by: NFrank Schäfer <fschaefer.oss@googlemail.com>
Tested-by: NAntti Palosaari <crope@iki.fi>
Signed-off-by: NMauro Carvalho Chehab <m.chehab@samsung.com>

URBs might be in usage. Disconnect the device before freeing
them.
Reviewed-by: NFrank Schäfer <fschaefer.oss@googlemail.com>
Tested-by: NAntti Palosaari <crope@iki.fi>
Signed-off-by: NMauro Carvalho Chehab <m.chehab@samsung.com>

Cleanup the error handling code at em28xx-audio init.
Reviewed-by: NFrank Schäfer <fschaefer.oss@googlemail.com>
Tested-by: NAntti Palosaari <crope@iki.fi>
Signed-off-by: NMauro Carvalho Chehab <m.chehab@samsung.com>

Alsa has an special non-negative return code to indicate device removal
at snd_em28xx_capture_pointer(). Use it, instead of an error code.
Reviewed-by: NFrank Schäfer <fschaefer.oss@googlemail.com>
Tested-by: NAntti Palosaari <crope@iki.fi>
Signed-off-by: NMauro Carvalho Chehab <m.chehab@samsung.com>

Remove some dead code from em28xx_v4l2_fini() and fix the leaking of the video,
vbi and radio video_device struct memories.
Signed-off-by: NFrank Schäfer <fschaefer.oss@googlemail.com>
Signed-off-by: NMauro Carvalho Chehab <m.chehab@samsung.com>

When the usb device is disconnected, the resources are no longer available,
so there is no reason to keep them registered.

This will also fix the various sysfs group removal warnings which we can see
since kernel 3.13.
Signed-off-by: NFrank Schäfer <fschaefer.oss@googlemail.com>
Signed-off-by: NMauro Carvalho Chehab <m.chehab@samsung.com>

[media] em28xx-v4l: move v4l2_ctrl_handler freeing and v4l2_device unregistration to em28xx_v4l2_fini

v4l2_ctrl_handler_free() and v4l2_device_unregister() are currently only called
when the last user closes the device and the device is already disconnected.
But that's wrong, we need to call these functions whenever the em28xx-v4l
extension is closed and we can already do this if the device is still opened
by some users.
Signed-off-by: NFrank Schäfer <fschaefer.oss@googlemail.com>
Signed-off-by: NMauro Carvalho Chehab <m.chehab@samsung.com>

Signed-off-by: NFrank Schäfer <fschaefer.oss@googlemail.com>
Signed-off-by: NMauro Carvalho Chehab <m.chehab@samsung.com>

Signed-off-by: NFrank Schäfer <fschaefer.oss@googlemail.com>
Signed-off-by: NMauro Carvalho Chehab <m.chehab@samsung.com>

Signed-off-by: NFrank Schäfer <fschaefer.oss@googlemail.com>
Signed-off-by: NMauro Carvalho Chehab <m.chehab@samsung.com>

[media] em28xx: move usb buffer pre-allocation and transfer uninit from the core to the dvb extension
Signed-off-by: NFrank Schäfer <fschaefer.oss@googlemail.com>
Signed-off-by: NMauro Carvalho Chehab <m.chehab@samsung.com>

- bail out on unsupported VFL_TYPE
- em28xx_set_mode() needs to be called for VBI and radio mode, too
- em28xx_wake_i2c() needs to be called for VBI and radio mode, too
- em28xx_resolution_set() also needs to be called for VBI
Signed-off-by: NFrank Schäfer <fschaefer.oss@googlemail.com>
Signed-off-by: NMauro Carvalho Chehab <m.chehab@samsung.com>

Now that em28xx can be compiled without V4L support, we should
call em28xx_setup_xc3028() on both em28xx-v4l and em28xx-dvb
modules.
Reported-by: NChris Lee <updatelee@gmail.com>
Signed-off-by: NMauro Carvalho Chehab <m.chehab@samsung.com>

If em28xx is disconnected, return -ENODEV to all PCM callbacks.
Signed-off-by: NMauro Carvalho Chehab <m.chehab@samsung.com>

The URB calculus code may eventually be moved to some other
place, like at pcm open, if it ends by needing more setups, like
working with different bit rates, or different audio latency.

So, move it into a separate routine. That also makes the code
more readable.

No functional changes.
Signed-off-by: NMauro Carvalho Chehab <m.chehab@samsung.com>

Pulseaudio has the bad habit of stopping a streaming audio if
a device, opened in non-block mode, waits.

It is impossible to avoid em28xx to wait, as it will send commands
via I2C, and other I2C operations may be happening (firmware
transfers, Remote Controller polling, etc). Yet, as each em28xx
subdriver locks em28xx-dev to protect the access to the hardware,
it is possible to minimize the audio glitches by returning -EAGAIN
to pulseaudio, if the lock is already taken by another subdriver.
Reported-by: NAntti Palosaari <crope@iki.fi>
Tested-by: NAntti Palosaari <crope@iki.fi>
Signed-off-by: NMauro Carvalho Chehab <m.chehab@samsung.com>

If the period size is wrong, userspace will assume a wrong delay
any may negociate an inadequate value.

The em28xx devices use 8 for URB interval, in microframes,
and the driver programs it to have 64 packets.

That means that the IRQ sampling period is 125 * 8 * 64,
with is equal to 64 ms.

So, that's the minimal latency with the current settings. It is
possible to program a lower latency, by using less than 64 packets,
but that increases the amount of bandwitdh used, and the number of
IRQ events per second.

In any case, in order to support it, the driver logic should be
changed to fill those parameters in realtime.
Signed-off-by: NMauro Carvalho Chehab <m.chehab@samsung.com>

The current code hardcodes the number of audio URBs, the number
of packets per URB and the maximum URB size.

This is not a good idea, as it:

- wastes more bandwidth than necessary, by using a very
  large number of packets;

- those constants are bound to an specific scenario, with
  a bandwidth of 48 kHz;

- don't take the maximum endpoint size into account;

- with urb->interval = 1 on xHCI, those constraints cause a "funny"
  setup: URBs with 64 packets inside, with only 24 bytes total. E. g.
  a complete waste of space.

Change the code to do dynamic URB audio calculus and allocation.

For now, use the same constraints as used before this patch, to
avoid regressions.

A good scenario (tested) seems to use those defines, instead:

	#define EM28XX_MAX_AUDIO_BUFS          8
	#define EM28XX_MIN_AUDIO_PACKETS       2

But let's not do such change here, letting the optimization to
happen on latter patches, after more tests.
Signed-off-by: NMauro Carvalho Chehab <m.chehab@samsung.com>

De-allocate memory and free sound if an error happens.
Signed-off-by: NMauro Carvalho Chehab <m.chehab@samsung.com>

Just filling urb->interval with 1 is wrong, and causes a different
behaviour with xHCI.

With EHCI, the URB size is typically 192 bytes. However, as
xHCI specifies intervals in microframes, the URB size becomes
too short (24 bytes).

With this patch, the interval will be properly initialized, and
the device will behave the same if connected into a xHCI or an
EHCI device port.
Signed-off-by: NMauro Carvalho Chehab <m.chehab@samsung.com>

If i2c_debug is enabled, we splicitly want to know when a
device fails with timeout.

If i2c_debug==2, this is already provided, for each I2C transfer
that fails.

However, most of the time, we don't need to go that far. We just
want to know that I2C transfers fail.

So, add such errors for normal (ret == 0x10) I2C aborted timeouts.
Signed-off-by: NMauro Carvalho Chehab <m.chehab@samsung.com>

The I2C output messages is too polluted. Clean it a little
bit, by:
	- use the proper core support for memory dumps;
	- hide most stuff under the i2c_debug umbrella;
	- add the missing KERN_CONT where needed;
	- use 2 levels or verbosity. Only the second one
	  will show the I2C transfer data.
Signed-off-by: NMauro Carvalho Chehab <m.chehab@samsung.com>

Follow the error codes for I2C as described at Documentation/i2c/fault-codes.

In the case of the I2C status register (0x05), this is mapped into:

	- ENXIO - when reg 05 returns 0x10
	- ETIMEDOUT - when the device is not temporarily not responding
		      (e. g. reg 05 returning something not 0x10 or 0x00)
	- EIO - for generic I/O errors that don't fit into the above.

In the specific case of 0-byte reads, used only during I2C device
probing, it keeps returning -ENODEV.

TODO: return EBUSY when reg 05 returns 0x20 on em2874 and upper.
Signed-off-by: NMauro Carvalho Chehab <m.chehab@samsung.com>

In the lack of a better spec, let's assume the timeout
values compatible with SMBus spec:
	http://smbus.org/specs/smbus110.pdf

at chapter 8 - Electrical Characteristics of SMBus devices

Ok, SMBus is a subset of I2C, and not all devices will be
following it, but the timeout value before this patch was not
even following the spec.

So, while we don't have a better guess for it, use 35 + 1
ms as the timeout.
Signed-off-by: NMauro Carvalho Chehab <m.chehab@samsung.com>

This macro is used by all em28xx devices, and not just em2800.
Reviewed-by: NFrank Schäfer <fschaefer.oss@googlemail.com>
Signed-off-by: NMauro Carvalho Chehab <m.chehab@samsung.com>

The I2C wait completion/timeout logic currently assumes that
msleep(5) will wait exaclty 5 ms. This is not true at all,
as it depends on CONFIG_HZ.

Convert it to use jiffies, in order to not wait for more time
than needed.
Signed-off-by: NMauro Carvalho Chehab <m.chehab@samsung.com>

Instead of assuming that msleep() is precise, use a jiffies
based code to wait for AC97 to be available.
Reviewed-by: NFrank Schäfer <fschaefer.oss@googlemail.com>
Signed-off-by: NMauro Carvalho Chehab <m.chehab@samsung.com>

Instead of allocating/deallocating URBs and transfer buffers
every time stream is started/stopped, just do it once.

That reduces the memory allocation pressure and makes the
code that start/stop streaming a way simpler.
Signed-off-by: NMauro Carvalho Chehab <mchehab@redhat.com>
Signed-off-by: NMauro Carvalho Chehab <m.chehab@samsung.com>

Instead of allocating transfer buffers with kmalloc() use
usb_alloc_coherent().

This patch should make it work also with ARM CPUs.
Reviewed-by: NFrank Schäfer <fschaefer.oss@googlemail.com>
Signed-off-by: NMauro Carvalho Chehab <m.chehab@samsung.com>

The audio configuration in chip config register 0x00 and eeprom are always
consistent. But currently the audio configuration #defines for the chip config
register say 0x20 means 3 sample rates and 0x30 5 sample rates, while the eeprom
info output says 0x20 means 1 sample rate and 0x30 3 sample rates.

I've checked the datasheet excerpts I have and it seems that the meaning of
these bits is different for em2820/40 (1 and 3 sample rates) and em2860+
(3 and 5 smaple rates).
I have also checked my Hauppauge WinTV USB 2 (em2840) and the chip/eeprom
audio config 0x20 matches the sample rates reproted by the USB device
descriptor (32k only).
Signed-off-by: NFrank Schäfer <fschaefer.oss@googlemail.com>
Signed-off-by: NMauro Carvalho Chehab <m.chehab@samsung.com>

As reported by the kbuild test robot:

All error/warnings:

>> ERROR: "em28xx_release_resources" [drivers/media/usb/em28xx/em28xx-v4l.ko] undefined!
Reported-by: Nkbuild test robot <fengguang.wu@intel.com>
Signed-off-by: NMauro Carvalho Chehab <m.chehab@samsung.com>

Emitting an OOM message isn't necessary after input_allocate_device
as there's a generic OOM and a dump_stack already done.
Signed-off-by: NJoe Perches <joe@perches.com>
Signed-off-by: NHans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: NMauro Carvalho Chehab <m.chehab@samsung.com>

For devices with a separated audio-only interface (em2860), call
em28xx_init_extension() only once.

That fixes a bug with Kworld 305U (eb1a:e305):

    [  658.730715] em2860 #0: V4L2 video device registered as video1
    [  658.730728] em2860 #0: V4L2 VBI device registered as vbi0
    [  658.736907] em2860 #0: Remote control support is not available for this card.
    [  658.736965] em2860 #1: Remote control support is not available for this card.
    [  658.737230] ------------[ cut here ]------------
    [  658.737246] WARNING: CPU: 2 PID: 60 at lib/list_debug.c:36 __list_add+0x8a/0xc0()
    [  658.737256] list_add double add: new=ffff8800a9a40410, prev=ffff8800a9a40410, next=ffffffffa08720d0.
    [  658.737266] Modules linked in: tuner_xc2028 netconsole rc_hauppauge em28xx_rc rc_core tuner_simple tuner_types tda9887 tda8290 tuner tvp5150 msp3400 em28xx_v4l em28xx tveeprom
 v4l2_common fuse ccm nf_conntrack_netbios_ns nf_conntrack_broadcast ipt_MASQUERADE ip6t_REJECT xt_conntrack ebtable_nat ebtable_broute bridge stp llc ebtable_filter ebtables ip6tabl
e_nat nf_conntrack_ipv6 nf_defrag_ipv6 nf_nat_ipv6 ip6table_mangle ip6table_security ip6table_raw ip6table_filter ip6_tables iptable_nat nf_conntrack_ipv4 nf_defrag_ipv4 nf_nat_ipv4
nf_nat nf_conntrack iptable_mangle iptable_security bnep iptable_raw vfat fat arc4 iwldvm mac80211 x86_pkg_temp_thermal coretemp kvm_intel nfsd iwlwifi snd_hda_codec_hdmi kvm snd_hda
_codec_realtek snd_hda_intel snd_hda_codec auth_rpcgss nfs_acl cfg80211 lockd snd_hwdep snd_seq btusb sunrpc crc32_pclmul bluetooth crc32c_intel snd_seq_device snd_pcm uvcvideo r8169
 ghash_clmulni_intel videobuf2_vmalloc videobuf2_memops videobuf2_core snd_page_alloc snd_timer snd videodev mei_me iTCO_wdt mii shpchp joydev mei media iTCO_vendor_support lpc_ich m
icrocode soundcore rfkill serio_raw i2c_i801 mfd_core nouveau i915 ttm i2c_algo_bit drm_kms_helper drm i2c_core mxm_wmi wmi video
    [  658.738601] CPU: 2 PID: 60 Comm: kworker/2:1 Not tainted 3.13.0-rc1+ #18
    [  658.738611] Hardware name: SAMSUNG ELECTRONICS CO., LTD. 550P5C/550P7C/SAMSUNG_NP1234567890, BIOS P04ABI.013.130220.dg 02/20/2013
    [  658.738624] Workqueue: events request_module_async [em28xx]
    [  658.738646]  0000000000000009 ffff8802209dfc68 ffffffff816a3c96 ffff8802209dfcb0
    [  658.738700]  ffff8802209dfca0 ffffffff8106aaad ffff8800a9a40410 ffffffffa08720d0
    [  658.738754]  ffff8800a9a40410 0000000000000000 0000000000000080 ffff8802209dfd00
    [  658.738814] Call Trace:
    [  658.738836]  [<ffffffff816a3c96>] dump_stack+0x45/0x56
    [  658.738851]  [<ffffffff8106aaad>] warn_slowpath_common+0x7d/0xa0
    [  658.738864]  [<ffffffff8106ab1c>] warn_slowpath_fmt+0x4c/0x50
    [  658.738880]  [<ffffffffa0868a7d>] ? em28xx_init_extension+0x1d/0x80 [em28xx]
    [  658.738898]  [<ffffffff81343b8a>] __list_add+0x8a/0xc0
    [  658.738911]  [<ffffffffa0868a98>] em28xx_init_extension+0x38/0x80 [em28xx]
    [  658.738927]  [<ffffffffa086a059>] request_module_async+0x19/0x110 [em28xx]
    [  658.738942]  [<ffffffff810873b5>] process_one_work+0x1f5/0x510
    [  658.738954]  [<ffffffff81087353>] ? process_one_work+0x193/0x510
    [  658.738967]  [<ffffffff810880bb>] worker_thread+0x11b/0x3a0
    [  658.738979]  [<ffffffff81087fa0>] ? manage_workers.isra.24+0x2b0/0x2b0
    [  658.738992]  [<ffffffff8108ea2f>] kthread+0xff/0x120
    [  658.739005]  [<ffffffff8108e930>] ? kthread_create_on_node+0x250/0x250
    [  658.739017]  [<ffffffff816b517c>] ret_from_fork+0x7c/0xb0
    [  658.739029]  [<ffffffff8108e930>] ? kthread_create_on_node+0x250/0x250
    [  658.739040] ---[ end trace c1acd24b354108de ]---
    [  658.739051] em2860 #1: Remote control support is not available for this card.
    [  658.742407] em28xx-audio.c: probing for em28xx Audio Vendor Class
    [  658.742429] em28xx-audio.c: Copyright (C) 2006 Markus Rechberger
    [  658.742440] em28xx-audio.c: Copyright (C) 2007-2011 Mauro Carvalho Chehab
    [  658.744798] em28xx-audio.c: probing for em28xx Audio Vendor Class
    [  658.744823] em28xx-audio.c: Copyright (C) 2006 Markus Rechberger
    [  658.744836] em28xx-audio.c: Copyright (C) 2007-2011 Mauro Carvalho Chehab
    [  658.746849] em28xx-audio.c: probing for em28xx Audio Vendor Class
    [  658.746863] em28xx-audio.c: Copyright (C) 2006 Markus Rechberger
    [  658.746874] em28xx-audio.c: Copyright (C) 2007-2011 Mauro Carvalho Chehab
    ...
Signed-off-by: NMauro Carvalho Chehab <m.chehab@samsung.com>