October 2017 - Alsa-devel - mailman.alsa-project.org

[alsa-devel] [PATCH] ALSA: seq: resize buffer for overflow
by Mark Salyzyn 06 Oct '17

06 Oct '17

Can not replicate, issue discovered in fuzzing. Stack trace below. No functional or performance testing done regarding the fix. Trap at (reformatted): snd_seq_oss_readq_puts(struct seq_oss_readq *q, int dev, unsigned char *data, int len) { union evrec rec; int result; memset(&rec, 0, sizeof(rec)); rec.c[0] = SEQ_MIDIPUTC; rec.c[2] = dev; while (len-- > 0) { rec.c[1] = *data++; // data is RBX HERE 'data' pointer just passed a page boundary, so the buffer supplied was short. Caller must have been handed an ev->type equal to SNDDRV_SEQ_EVENT_SYSEX, which resulted in handing off ev->data.ext.ptr[ev->data.ext.len] buffer. Intuited that the source of the event and buffer was referenced in snd_midi_event_encode_byte() passing a larger length than the allocated buffer. BUG: unable to handle kernel paging request at ffffc900008ab000 IP: [<ffffffff82e2fc05>] snd_seq_oss_readq_puts+0xd5/0x170 sound/core/seq/oss/seq_oss_readq.c:112 PGD 1da091067 PUD 1da092067 Oops: 0000 [#1] PREEMPT SMP KASAN Dumping ftrace buffer: (ftrace buffer empty) Modules linked in: CPU: 1 PID: 3264 Comm: XXXXXXXX Hardware name: XXXXXXXXXX task: ffff8801cdd9e000 task.stack: ffff8801ce648000 RIP: 0010:[<ffffffff82e2fc05>] [<ffffffff82e2fc05>] snd_seq_oss_readq_puts+0xd5/0x170 sound/core/seq/oss/seq_oss_readq.c:112 RSP: 0018:ffff8801ce64f1c0 EFLAGS: 00010246 RAX: 0000000000000000 RBX: ffffc900008ab000 RCX: 0000000000000000 RDX: 0000000000000000 RSI: 0000000000000001 RDI: ffffffff858e5780 RBP: ffff8801ce64f260 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 1ffff10039cc9df2 R12: 000000003fffffa4 R13: dffffc0000000000 R14: ffff8801ce64f238 R15: ffffc900008ab001 FS: 00007fe3d3d9e700(0000) GS:ffff8801db300000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: ffffc900008ab000 CR3: 00000001d19b7000 CR4: 00000000001406e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Stack: 1ffff10039cc9e3b ffff8801ce64f1f8 ffff8801d0b9aa00 0000000041b58ab3 ffffffff841daf3c ffffffff82e2fb30 0000000000000286 0000000000000005 ffffffff838aa5d5 ffffffff861962c0 dffffc0000000000 ffff8801ce64f260 Call Trace: [<ffffffff82e2ebbe>] send_midi_event sound/core/seq/oss/seq_oss_midi.c:616 [inline] [<ffffffff82e2ebbe>] snd_seq_oss_midi_input+0x8ce/0xa70 sound/core/seq/oss/seq_oss_midi.c:535 [<ffffffff82e2758d>] snd_seq_oss_event_input+0x15d/0x220 sound/core/seq/oss/seq_oss_event.c:439 [<ffffffff82e0b650>] snd_seq_deliver_single_event.constprop.11+0x310/0x7c0 sound/core/seq/seq_clientmgr.c:621 [<ffffffff82e0be16>] deliver_to_subscribers sound/core/seq/seq_clientmgr.c:676 [inline] [<ffffffff82e0be16>] snd_seq_deliver_event+0x316/0x740 sound/core/seq/seq_clientmgr.c:807 [<ffffffff82e0cf9e>] snd_seq_kernel_client_dispatch+0x11e/0x150 sound/core/seq/seq_clientmgr.c:2314 [<ffffffff82e31775>] dummy_input+0x235/0x320 sound/core/seq/seq_dummy.c:104 [<ffffffff82e0b650>] snd_seq_deliver_single_event.constprop.11+0x310/0x7c0 sound/core/seq/seq_clientmgr.c:621 [<ffffffff82e0bc2d>] snd_seq_deliver_event+0x12d/0x740 sound/core/seq/seq_clientmgr.c:818 [<ffffffff82e0d0ed>] snd_seq_dispatch_event+0x11d/0x520 sound/core/seq/seq_clientmgr.c:892 [<ffffffff82e1117e>] snd_seq_check_queue.part.3+0x38e/0x510 sound/core/seq/seq_queue.c:285 [<ffffffff82e11d8d>] snd_seq_check_queue sound/core/seq/seq_queue.c:357 [inline] [<ffffffff82e11d8d>] snd_seq_enqueue_event+0x32d/0x3d0 sound/core/seq/seq_queue.c:363 [<ffffffff82e0c444>] snd_seq_client_enqueue_event+0x204/0x3e0 sound/core/seq/seq_clientmgr.c:951 [<ffffffff82e0cc55>] kernel_client_enqueue.part.10+0xb5/0xd0 sound/core/seq/seq_clientmgr.c:2251 [<ffffffff82e0cd3f>] kernel_client_enqueue sound/core/seq/seq_clientmgr.c:2241 [inline] [<ffffffff82e0cd3f>] snd_seq_kernel_client_enqueue_blocking+0xcf/0x110 sound/core/seq/seq_clientmgr.c:2279 [<ffffffff82e27f68>] insert_queue sound/core/seq/oss/seq_oss_rw.c:189 [inline] [<ffffffff82e27f68>] snd_seq_oss_write+0x538/0x850 sound/core/seq/oss/seq_oss_rw.c:148 [<ffffffff82e1fab4>] odev_write+0x64/0x90 sound/core/seq/oss/seq_oss.c:177 [<ffffffff8156ab43>] __vfs_write+0x103/0x680 fs/read_write.c:510 [<ffffffff8156ec70>] vfs_write+0x170/0x4e0 fs/read_write.c:560 [<ffffffff81572669>] SYSC_write fs/read_write.c:607 [inline] [<ffffffff81572669>] SyS_write+0xd9/0x1b0 fs/read_write.c:599 [<ffffffff838aad85>] entry_SYSCALL_64_fastpath+0x23/0xc6 Code: 4d 9a eb 4e e8 2d aa 53 fe 4c 8d 7b 01 48 89 d8 48 89 d9 48 c1 e8 03 83 e1 07 42 0f b6 04 28 38 c8 7f 08 84 c0 0f 85 80 00 00 00 <41> 0f b6 47 ff 41 83 ec 01 48 8b b5 68 ff ff ff 48 8b bd 70 ff RIP [<ffffffff82e2fc05>] snd_seq_oss_readq_puts+0xd5/0x170 sound/core/seq/oss/seq_oss_readq.c:112 RSP <ffff8801ce64f1c0> CR2: ffffc900008ab000 Signed-off-by: Mark Salyzyn <salyzyn(a)android.com> --- sound/core/seq/seq_midi_event.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) diff --git a/sound/core/seq/seq_midi_event.c b/sound/core/seq/seq_midi_event.c index 90bbbdbeba03..cbc501fd47c2 100644 --- a/sound/core/seq/seq_midi_event.c +++ b/sound/core/seq/seq_midi_event.c @@ -192,8 +192,7 @@ EXPORT_SYMBOL(snd_midi_event_no_status); /* * resize buffer */ -#if 0 -int snd_midi_event_resize_buffer(struct snd_midi_event *dev, int bufsize) +static int snd_midi_event_resize_buffer(struct snd_midi_event *dev, int bufsize) { unsigned char *new_buf, *old_buf; unsigned long flags; @@ -212,7 +211,6 @@ int snd_midi_event_resize_buffer(struct snd_midi_event *dev, int bufsize) kfree(old_buf); return 0; } -#endif /* 0 */ /* * read bytes and encode to sequencer event if finished @@ -297,6 +295,8 @@ int snd_midi_event_encode_byte(struct snd_midi_event *dev, int c, } else if (dev->type == ST_SYSEX) { if (c == MIDI_CMD_COMMON_SYSEX_END || dev->read >= dev->bufsize) { + if (dev->read > dev->bufsize) + snd_midi_event_resize_buffer(dev, dev->read); ev->flags &= ~SNDRV_SEQ_EVENT_LENGTH_MASK; ev->flags |= SNDRV_SEQ_EVENT_LENGTH_VARIABLE; ev->type = SNDRV_SEQ_EVENT_SYSEX; -- 2.14.2.920.gcf0c67979c-goog

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Re: [alsa-devel] [PATCH] alsactl: Move systemd unit start-up from basic.target to sound.target
by Takashi Iwai 06 Oct '17

06 Oct '17

On Tue, 26 Sep 2017 20:36:12 +0200, Chris Mayo wrote: > > Ensures soundcard is ready before restoring state. > > sound.target added to systemd in v18: > https://cgit.freedesktop.org/systemd/systemd/commit/?id=88dfa2938af > > Simplify dependencies: > - After=alsa-state.service is not needed because both units test for > @daemonswitch@ with opposite outcomes. > > - After=sysinit.target is automatically added by systemd. > > First proposed by Tom Yan. > > Signed-off-by: Chris Mayo <aklhfex(a)gmail.com> > --- > > I need this because my Sound Blaster Titanium is not ready by the time > basic.target is reached. > > It was proposed last year by Tom Yan but looks like it didn't get in > because requested config checks and documentation didn't materialise. > https://www.spinics.net/lists/alsa-devel/msg45537.html > > I've added those (PKG_CHECK_MODULES outputs a message at configure time). > > I've left ConditionPathExistsGlob=/dev/snd/control* in > alsa-restore.service because although it would normally be started by the > udev rule and sound.target there's no guarantee that is how it was started. Thanks, this looks like a sensitive change. Applied now. Takashi

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[alsa-devel] [PATCH] ALSA: usb-audio: Add sample rate quirk for Plantronics P610
by Kai-Heng Feng 06 Oct '17

06 Oct '17

Like other Plantronics devices, P610 does not support sample rate reading. Apply sample rate quirk to it. BugLink: https://bugs.launchpad.net/bugs/1719853 Signed-off-by: Kai-Heng Feng <kai.heng.feng(a)canonical.com> --- sound/usb/quirks.c | 1 + 1 file changed, 1 insertion(+) diff --git a/sound/usb/quirks.c b/sound/usb/quirks.c index b8cb57aeec77..9ddaae3784f5 100644 --- a/sound/usb/quirks.c +++ b/sound/usb/quirks.c @@ -1138,6 +1138,7 @@ bool snd_usb_get_sample_rate_quirk(struct snd_usb_audio *chip) case USB_ID(0x047F, 0x0415): /* Plantronics BT-300 */ case USB_ID(0x047F, 0xAA05): /* Plantronics DA45 */ case USB_ID(0x047F, 0xC022): /* Plantronics C310 */ + case USB_ID(0x047F, 0xC02F): /* Plantronics P610 */ case USB_ID(0x047F, 0xC036): /* Plantronics C520-M */ case USB_ID(0x04D8, 0xFEEA): /* Benchmark DAC1 Pre */ case USB_ID(0x0556, 0x0014): /* Phoenix Audio TMX320VC */ -- 2.14.1

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[alsa-devel] [asoc:topic/dapm 4/4] sound//soc/soc-dapm.c:3940:2: warning: 'w_param_text' may be used uninitialized in this function
by kbuild test robot 05 Oct '17

05 Oct '17

tree: https://git.kernel.org/pub/scm/linux/kernel/git/broonie/sound.git topic/dapm head: 19ad683abc8534cd755403381c73c0ddce7b9f6d commit: 19ad683abc8534cd755403381c73c0ddce7b9f6d [4/4] ASoC: dapm: Avoid creating kcontrol for params config: i386-randconfig-x079-201740 (attached as .config) compiler: gcc-6 (Debian 6.2.0-3) 6.2.0 20160901 reproduce: git checkout 19ad683abc8534cd755403381c73c0ddce7b9f6d # save the attached .config to linux build tree make ARCH=i386 Note: it may well be a FALSE warning. FWIW you are at least aware of it now. http://gcc.gnu.org/wiki/Better_Uninitialized_Warnings All warnings (new ones prefixed by >>): sound//soc/soc-dapm.c: In function 'snd_soc_dapm_new_pcm': >> sound//soc/soc-dapm.c:3940:2: warning: 'w_param_text' may be used uninitialized in this function [-Wmaybe-uninitialized] snd_soc_dapm_free_kcontrol(card, &private_value, num_params, w_param_text); ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ vim +/w_param_text +3940 sound//soc/soc-dapm.c 3862 3863 int snd_soc_dapm_new_pcm(struct snd_soc_card *card, 3864 const struct snd_soc_pcm_stream *params, 3865 unsigned int num_params, 3866 struct snd_soc_dapm_widget *source, 3867 struct snd_soc_dapm_widget *sink) 3868 { 3869 struct snd_soc_dapm_widget template; 3870 struct snd_soc_dapm_widget *w; 3871 const char **w_param_text; 3872 unsigned long private_value; 3873 char *link_name; 3874 int ret; 3875 3876 link_name = devm_kasprintf(card->dev, GFP_KERNEL, "%s-%s", 3877 source->name, sink->name); 3878 if (!link_name) 3879 return -ENOMEM; 3880 3881 memset(&template, 0, sizeof(template)); 3882 template.reg = SND_SOC_NOPM; 3883 template.id = snd_soc_dapm_dai_link; 3884 template.name = link_name; 3885 template.event = snd_soc_dai_link_event; 3886 template.event_flags = SND_SOC_DAPM_PRE_PMU | SND_SOC_DAPM_POST_PMU | 3887 SND_SOC_DAPM_PRE_PMD; 3888 template.kcontrol_news = NULL; 3889 3890 /* allocate memory for control, only in case of multiple configs */ 3891 if (num_params > 1) { 3892 w_param_text = devm_kcalloc(card->dev, num_params, 3893 sizeof(char *), GFP_KERNEL); 3894 if (!w_param_text) { 3895 ret = -ENOMEM; 3896 goto param_fail; 3897 } 3898 3899 template.num_kcontrols = 1; 3900 template.kcontrol_news = 3901 snd_soc_dapm_alloc_kcontrol(card, 3902 link_name, params, num_params, 3903 w_param_text, &private_value); 3904 if (!template.kcontrol_news) { 3905 ret = -ENOMEM; 3906 goto param_fail; 3907 } 3908 } 3909 dev_dbg(card->dev, "ASoC: adding %s widget\n", link_name); 3910 3911 w = snd_soc_dapm_new_control_unlocked(&card->dapm, &template); 3912 if (IS_ERR(w)) { 3913 ret = PTR_ERR(w); 3914 /* Do not nag about probe deferrals */ 3915 if (ret != -EPROBE_DEFER) 3916 dev_err(card->dev, 3917 "ASoC: Failed to create %s widget (%d)\n", 3918 link_name, ret); 3919 goto outfree_kcontrol_news; 3920 } 3921 if (!w) { 3922 dev_err(card->dev, "ASoC: Failed to create %s widget\n", 3923 link_name); 3924 ret = -ENOMEM; 3925 goto outfree_kcontrol_news; 3926 } 3927 3928 w->params = params; 3929 w->num_params = num_params; 3930 3931 ret = snd_soc_dapm_add_path(&card->dapm, source, w, NULL, NULL); 3932 if (ret) 3933 goto outfree_w; 3934 return snd_soc_dapm_add_path(&card->dapm, w, sink, NULL, NULL); 3935 3936 outfree_w: 3937 devm_kfree(card->dev, w); 3938 outfree_kcontrol_news: 3939 devm_kfree(card->dev, (void *)template.kcontrol_news); > 3940 snd_soc_dapm_free_kcontrol(card, &private_value, num_params, w_param_text); 3941 param_fail: 3942 devm_kfree(card->dev, link_name); 3943 return ret; 3944 } 3945 --- 0-DAY kernel test infrastructure Open Source Technology Center https://lists.01.org/pipermail/kbuild-all Intel Corporation

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[alsa-devel] [PATCH 00/18] use ARRAY_SIZE macro
by Jérémy Lefaure 05 Oct '17

05 Oct '17

Hi everyone, Using ARRAY_SIZE improves the code readability. I used coccinelle (I made a change to the array_size.cocci file [1]) to find several places where ARRAY_SIZE could be used instead of other macros or sizeof division. I tried to divide the changes into a patch per subsystem (excepted for staging). If one of the patch should be split into several patches, let me know. In order to reduce the size of the To: and Cc: lines, each patch of the series is sent only to the maintainers and lists concerned by the patch. This cover letter is sent to every list concerned by this series. This series is based on linux-next next-20170929. Each patch has been tested by building the relevant files with W=1. This series contains the following patches: [PATCH 01/18] sound: use ARRAY_SIZE [PATCH 02/18] tracing/filter: use ARRAY_SIZE [PATCH 03/18] media: use ARRAY_SIZE [PATCH 04/18] IB/mlx5: Use ARRAY_SIZE [PATCH 05/18] net: use ARRAY_SIZE [PATCH 06/18] drm: use ARRAY_SIZE [PATCH 07/18] scsi: bfa: use ARRAY_SIZE [PATCH 08/18] ecryptfs: use ARRAY_SIZE [PATCH 09/18] nfsd: use ARRAY_SIZE [PATCH 10/18] orangefs: use ARRAY_SIZE [PATCH 11/18] dm space map metadata: use ARRAY_SIZE [PATCH 12/18] x86: use ARRAY_SIZE [PATCH 13/18] tpm: use ARRAY_SIZE [PATCH 14/18] ipmi: use ARRAY_SIZE [PATCH 15/18] acpi: use ARRAY_SIZE [PATCH 16/18] media: staging: atomisp: use ARRAY_SIZE [PATCH 17/18] staging: rtl8723bs: use ARRAY_SIZE [PATCH 18/18] staging: rtlwifi: use ARRAY_SIZE [1]: https://lkml.org/lkml/2017/9/13/689

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[alsa-devel] [PATCH] ALSA: sh: aica: Convert timers to use timer_setup()
by Kees Cook 05 Oct '17

05 Oct '17

In preparation for unconditionally passing the struct timer_list pointer to all timer callbacks, switch to using the new timer_setup() and from_timer() to pass the timer pointer explicitly. This requires adding a pointer to hold the timer's target substream, as there won't be a way to pass this in the future. Cc: Jaroslav Kysela <perex(a)perex.cz> Cc: Takashi Iwai <tiwai(a)suse.com> Cc: Bhumika Goyal <bhumirks(a)gmail.com> Cc: Mark Brown <broonie(a)kernel.org> Cc: alsa-devel(a)alsa-project.org Cc: Thomas Gleixner <tglx(a)linutronix.de> Signed-off-by: Kees Cook <keescook(a)chromium.org> --- This requires commit 686fef928bba ("timer: Prepare to change timer callback argument type") in v4.14-rc3, but should be otherwise stand-alone. --- sound/sh/aica.c | 20 +++++++++----------- 1 file changed, 9 insertions(+), 11 deletions(-) diff --git a/sound/sh/aica.c b/sound/sh/aica.c index fdc680ae8aa0..2b26311405a4 100644 --- a/sound/sh/aica.c +++ b/sound/sh/aica.c @@ -299,14 +299,14 @@ static void run_spu_dma(struct work_struct *work) } } -static void aica_period_elapsed(unsigned long timer_var) +static void aica_period_elapsed(struct timer_list *t) { + struct snd_card_aica *dreamcastcard = from_timer(dreamcastcard, + t, timer); + struct snd_pcm_substream *substream = dreamcastcard->timer_substream; /*timer function - so cannot sleep */ int play_period; struct snd_pcm_runtime *runtime; - struct snd_pcm_substream *substream; - struct snd_card_aica *dreamcastcard; - substream = (struct snd_pcm_substream *) timer_var; runtime = substream->runtime; dreamcastcard = substream->pcm->private_data; /* Have we played out an additional period? */ @@ -336,12 +336,12 @@ static void spu_begin_dma(struct snd_pcm_substream *substream) /*get the queue to do the work */ schedule_work(&(dreamcastcard->spu_dma_work)); /* Timer may already be running */ - if (unlikely(dreamcastcard->timer.data)) { + if (unlikely(dreamcastcard->timer_substream)) { mod_timer(&dreamcastcard->timer, jiffies + 4); return; } - setup_timer(&dreamcastcard->timer, aica_period_elapsed, - (unsigned long) substream); + timer_setup(&dreamcastcard->timer, aica_period_elapsed, 0); + dreamcastcard->timer_substream = substream; mod_timer(&dreamcastcard->timer, jiffies + 4); } @@ -379,7 +379,7 @@ static int snd_aicapcm_pcm_close(struct snd_pcm_substream { struct snd_card_aica *dreamcastcard = substream->pcm->private_data; flush_work(&(dreamcastcard->spu_dma_work)); - if (dreamcastcard->timer.data) + if (dreamcastcard->timer_substream) del_timer(&dreamcastcard->timer); kfree(dreamcastcard->channel); spu_disable(); @@ -600,7 +600,7 @@ static int snd_aica_probe(struct platform_device *devptr) { int err; struct snd_card_aica *dreamcastcard; - dreamcastcard = kmalloc(sizeof(struct snd_card_aica), GFP_KERNEL); + dreamcastcard = kzalloc(sizeof(struct snd_card_aica), GFP_KERNEL); if (unlikely(!dreamcastcard)) return -ENOMEM; err = snd_card_new(&devptr->dev, index, SND_AICA_DRIVER, @@ -619,8 +619,6 @@ static int snd_aica_probe(struct platform_device *devptr) err = snd_aicapcmchip(dreamcastcard, 0); if (unlikely(err < 0)) goto freedreamcast; - dreamcastcard->timer.data = 0; - dreamcastcard->channel = NULL; /* Add basic controls */ err = add_aicamixer_controls(dreamcastcard); if (unlikely(err < 0)) -- 2.7.4 -- Kees Cook Pixel Security

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[alsa-devel] [PATCH 0/2] ASoC: img-i2s-in: Add power management
by Ed Blake 05 Oct '17

05 Oct '17

This patch set adds power managment to the img-i2s-in driver. The first patch adds system PM suspend / resume handling and the second patch adds runtime PM. Ed Blake (2): ASoC: img-i2s-in: Add suspend / resume handling ASoC: img-i2s-in: Add runtime PM sound/soc/img/img-i2s-in.c | 126 ++++++++++++++++++++++++++++++++++++++++----- 1 file changed, 114 insertions(+), 12 deletions(-) -- 1.9.1

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[alsa-devel] [PATCH] conf: HdmiLpeAudio: remove the "front" pcm definition
by Tanu Kaskinen 05 Oct '17

05 Oct '17

PulseAudio assumes that the "front" pcm device always refers to an analog device, not HDMI. While that assumption is not really valid, the reality is that without that assumption PulseAudio can't know whether "front" and "hdmi" refer to a different or the same device. The HDMI LPE driver doesn't allow audio streaming while the HDMI cable is unplugged, so PulseAudio has to know when it's plugged in and when it's not. If both "front" and "hdmi" devices exist, PulseAudio will notice that HDMI is unplugged, but it doesn't know that "front" refers to the same device, and PulseAudio will try to use the "front" device with bad consequences. The kernel driver's refusal to stream any audio makes PulseAudio enter an infinite loop and then the kernel kills PulseAudio, because it consumes too much CPU time in a realtime thread. While the looping in PulseAudio could probably be fixed, that wouldn't change the fact that PulseAudio thinks that there is an analog device. I believe it's best to avoid having the same device as both "front" and "hdmi" in alsa-lib. I removed also the surround configuration includes. I don't think they had any effect anyway, so I wonder why they were there in the first place. BugLink: https://bugs.freedesktop.org/show_bug.cgi?id=100488 --- src/conf/cards/HdmiLpeAudio.conf | 24 ------------------------ 1 file changed, 24 deletions(-) diff --git a/src/conf/cards/HdmiLpeAudio.conf b/src/conf/cards/HdmiLpeAudio.conf index 9fa30da0..a1e493da 100644 --- a/src/conf/cards/HdmiLpeAudio.conf +++ b/src/conf/cards/HdmiLpeAudio.conf @@ -2,30 +2,6 @@ # Configuration for the Intel HDMI/DP LPE audio # -<confdir:pcm/front.conf> - -HdmiLpeAudio.pcm.front.0 { - @args [ CARD ] - @args.CARD { - type string - } - type softvol - slave.pcm { - type hw - card $CARD - } - control { - name "PCM Playback Volume" - card $CARD - } -} - -<confdir:pcm/surround40.conf> -<confdir:pcm/surround21.conf> -<confdir:pcm/surround41.conf> -<confdir:pcm/surround50.conf> -<confdir:pcm/surround51.conf> - <confdir:pcm/hdmi.conf> HdmiLpeAudio.pcm.hdmi.0 { -- 2.14.2

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[alsa-devel] SEGFault when optininal snd_ctl_ext_callback::read_event() not set
by Wischer, Timo (ADITG/ESB) 05 Oct '17

05 Oct '17

Hi all, snd_ctl_ext_callback::read_event() callback is mentioned as optional (see http://git.alsa-project.org/?p=alsa-lib.git;a=blob;f=include/control_extern…) but there is no NULL check and the NULL pointer will be called if the read_event function callback pointer is not set. (see http://git.alsa-project.org/?p=alsa-lib.git;a=blob;f=src/control/control_ex…) I think a default function has to be provided which will be called when the callback is not set or the read_event() callback should not be marked as optional. What is your opinion? Best regards Timo Wischer Advanced Driver Information Technology GmbH Engineering Software Base (ADITG/ESB) Robert-Bosch-Str. 200 31139 Hildesheim Germany Tel. +49 5121 49 6938 Fax +49 5121 49 6999 twischer(a)de.adit-jv.com ADIT is a joint venture company of Robert Bosch GmbH/Robert Bosch Car Multimedia GmbH and DENSO Corporation Sitz: Hildesheim, Registergericht: Amtsgericht Hildesheim HRB 3438 Geschäftsführung: Wilhelm Grabow, Ken Yaguchi

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[alsa-devel] notifying userspace of hwparams change
by Tim Harvey 05 Oct '17

05 Oct '17

Greetings, I've got an HDMI receiver chip I'm working on a driver for which provides the audio signal from the HDMI source. An HDMI source can be a variety of sample-rates, channels, widths, and formats. If I understand correctly I need to register the device as supporting all the possible rates/channels/formats then constrain these to what is actually available at the time in the startup callback with snd_pcm_hw_contstraint_minmax and snd_pcm_hw_constraint_mask. How do I notify userspace when the chip tells me that the HDMI audio source rate/channels/format has changed? I know on the Video side the driver sends a V4L2_EVENT_SOURCE_CHANGE event to userspace when input format/resolution has changed so that userspace can stop streaming, call VIDIOC_QUERY_DV_TIMINGS and then VIDIOC_S_DV_TIMINGS with new timings. Regards, Tim

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