As explained in "Writing an ALSA driver" (T. Iwai), audio drivers should
set the struct device for the card before registering the card instance.
This will add the correct /sys/class/sound/cardN/device symlink, so HAL
can see the device and ConsoleKit sets its ACL permissions for the
logged-in user.
For em28xx audio capture cards found e.g. in Hauppauge WinTV-HVR-900 (R2),
this patch fixes errors like:
ALSA lib pcm_hw.c:1429:(_snd_pcm_hw_open) Invalid value for card
Error opening audio: Permission denied
when running mplayer as a normal user.
Signed-off-by: Nicola Soranzo <nsoranzo@tiscali.it>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
Trace: (Provided by Douglas)
BUG: sleeping function called from invalid context at drivers/usb/core/urb.c:558
in_atomic():0, irqs_disabled():1
Pid: 4918, comm: sox Not tainted 2.6.27.5 #1
[<c04246d8>] __might_sleep+0xc6/0xcb
[<c058c8b0>] usb_kill_urb+0x1a/0xd8
[<c0488e68>] ? __kmalloc+0x9b/0xfc
[<c0488e85>] ? __kmalloc+0xb8/0xfc
[<c058cd5a>] ? usb_alloc_urb+0xf/0x31
[<f8dd638c>] em28xx_isoc_audio_deinit+0x2f/0x6c [em28xx_alsa]
[<f8dd6573>] em28xx_cmd+0x1aa/0x1c5 [em28xx_alsa]
[<f8dd65e1>] snd_em28xx_capture_trigger+0x53/0x68 [em28xx_alsa]
[<f8aa8674>] snd_pcm_do_start+0x1c/0x23 [snd_pcm]
[<f8aa85d7>] snd_pcm_action_single+0x25/0x4b [snd_pcm]
[<f8aa9833>] snd_pcm_action+0x6a/0x76 [snd_pcm]
[<f8aa98f5>] snd_pcm_start+0x14/0x16 [snd_pcm]
[<f8aae10e>] snd_pcm_lib_read1+0x66/0x273 [snd_pcm]
[<f8aac5a3>] ? snd_pcm_kernel_ioctl+0x46/0x5f [snd_pcm]
[<f8aae4a7>] snd_pcm_lib_read+0xbf/0xcd [snd_pcm]
[<f8aad774>] ? snd_pcm_lib_read_transfer+0x0/0xaf [snd_pcm]
[<f89feeb6>] snd_pcm_oss_read3+0x99/0xdc [snd_pcm_oss]
[<f89fef9c>] snd_pcm_oss_read2+0xa3/0xbf [snd_pcm_oss]
[<c064169d>] ? _cond_resched+0x8/0x32
[<f89ff0be>] snd_pcm_oss_read+0x106/0x150 [snd_pcm_oss]
[<f89fefb8>] ? snd_pcm_oss_read+0x0/0x150 [snd_pcm_oss]
[<c048c6e2>] vfs_read+0x81/0xdc
[<c048c7d6>] sys_read+0x3b/0x60
[<c04039bf>] sysenter_do_call+0x12/0x34
=======================
The culprit in the trace is snd_pcm_action() which invokes a spin lock
which disables pre-emption which disables an IRQ which causes the
__might_sleep() function to fail the irqs_disabled() test. Since
pre-emption is enabled then it is safe to de-allocate the memory if
you first unlink each URB. In this instance you are safe since
pre-emption is disabled. If pre-emption and irqs are not disabled then
call usb_kill_urb(), else call usb_unlink_urb().
Thanks to Douglas for tracking down this bug originally!!!
[dougsland@redhat.com: Fixed codyingstyle]
Signed-off-by: Robert Krakora <rob.krakora@messagenetsystems.com>
Signed-off-by: Douglas Schilling Landgraf <dougsland@redhat.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
Revert a change made in change 9743 which resulted in a kernel panic in some
cases on shutdown of the audio stream.
First discovered when working on the Pinnacle 880e support, and later
reproduced by a user on the mailing list with the HVR-900 as well.
Signed-off-by: Devin Heitmueller <dheitmueller@linuxtv.org>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
Some devices require different setups on struct_audio. Due to that, we
may need to change some fields at dev.adev during device probe. So, this
patch moves the dynamic memory allocation of adev at em28xx-alsa to the
dynamic allocation of struct em28xx dev that happens during device
probe.
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
Rework the logic so that the em28xx-alsa module does not get loaded for devices
that don't support analog audio (such as the em2874)
Signed-off-by: Devin Heitmueller <devin.heitmueller@gmail.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
commit 50f3beb50a fixed em28xx-alsa
locking schema. However, a backport macro was kept.
This patch removes the macro, since it is not needed for the module
compilation against upstream.
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
Replaced usb_kill_usb for usb_unlink_usb
(wait until urb to fully stop require USB core to put the calling process to sleep).
Oops:
http://www.kerneloops.org/raw.php?rawid=71799&msgid=
Signed-off-by: Douglas Schilling Landgraf <dougsland@linuxtv.org>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
Fixed audio clicking problem which could be heard when using analog tv or composite input
Signed-off-by: Wiktor Grebla <greblus@gmail.com>
Signed-off-by: Douglas Schilling Landgraf <dougsland@linuxtv.org>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
em28xx-audio.c
em28xx-dvb.c
- Em28xx extensions should ensure they are being only loaded against devices
that support them. Deals with case where there are multiple em28xx
devices, some of which have DVB (or ALSA) support and some do not.
Signed-off-by: Devin Heitmueller <devin.heitmueller@gmail.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@infradead.org>
__FUNCTION__ is gcc-specific, use __func__
Signed-off-by: Harvey Harrison <harvey.harrison@gmail.com>
Signed-off-by: Michael Krufky <mkrufky@linuxtv.org>
Signed-off-by: Mauro Carvalho Chehab <mchehab@infradead.org>
Older em28xx devices does implement standard Audio Class.
However, on newer devices, this were replaced by a Vendor Class. This
patch autodetects that an em28xx lacks Audio Class and auto-loads
em28xx-alsa, for the devices that implements only a Vendor Class.
For devices with Audio Class, snd-usb-audio module will provide an ALSA
interface.
This patch uses the request_module_async function as defined on cx88-mpeg.c,
originally wrote by Markus Rechberger.
Signed-off-by: Mauro Carvalho Chehab <mchehab@infradead.org>
em28xx-audio module exports em28xx Vendor Class audio as an -alsa
driver. This module were written based on usbaudio driver by Markus
Rechberger. Recently, he acked to allow us to merge it on kernel:
http://lists-archives.org/video4linux/20408-supporting-prolink-pixelview-405-dvd-maker.html
Thanks to Markus Rechberger <mrechberger@gmail.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@infradead.org>
