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* ALSA: pcm: Direct in-kernel read/write supportTakashi Iwai2017-06-021-1/+25
| | | | | | | | | | | | | | | | | | | | | Now all materials are ready, let's allow the direct in-kernel read/write, i.e. a kernel-space buffer is passed for read or write, instead of the normal user-space buffer. This feature is used by OSS layer and UAC1 driver, for example. The __snd_pcm_lib_xfer() takes in_kernel argument that indicates the in-kernel buffer copy. When this flag is set, another transfer code is used. It's either via copy_kernel PCM ops or the normal memcpy(), depending on the driver setup. As external API, snd_pcm_kernel_read(), *_write() and other variants are provided. That's all. This support is really simple because of the code refactoring until now. Reviewed-by: Takashi Sakamoto <o-takashi@sakamocchi.jp> Signed-off-by: Takashi Iwai <tiwai@suse.de>
* ALSA: pcm: Simplify snd_pcm_playback_silence()Takashi Iwai2017-06-021-30/+20
| | | | | | | Use the existing silence helper codes for simplification. Reviewed-by: Takashi Sakamoto <o-takashi@sakamocchi.jp> Signed-off-by: Takashi Iwai <tiwai@suse.de>
* ALSA: pcm: Unify read/write loopTakashi Iwai2017-06-021-138/+46
| | | | | | | | | | | Both __snd_pcm_lib_read() and __snd_pcm_write() functions have almost the same code to loop over samples. For simplification, this patch unifies both as the single helper, __snd_pcm_lib_xfer(). Other than that, there should be no functional change by this patch. Reviewed-by: Takashi Sakamoto <o-takashi@sakamocchi.jp> Signed-off-by: Takashi Iwai <tiwai@suse.de>
* ALSA: pcm: More unification of PCM transfer codesTakashi Iwai2017-06-021-131/+123
| | | | | | | | | | | | | | | | | | | | | | | | This patch proceeds more abstraction of PCM read/write loop codes. For both interleaved and non-interleaved transfers, the same copy or silence transfer code (which is defined as pcm_transfer_f) is used now. This became possible since we switched to byte size to copy_* and fill_silence ops argument instead of frames. And, for both read and write, we can use the same copy function (which is defined as pcm_copy_f), just depending on whether interleaved or non-interleaved mode. The transfer function is determined at the beginning of the loop, depending on whether the driver gives the specific copy ops or it's the standard read/write. Another bonus by this change is that we now guarantee the silencing behavior when NULL buffer is passed to write helpers. It'll simplify some codes later. Reviewed-by: Takashi Sakamoto <o-takashi@sakamocchi.jp> Signed-off-by: Takashi Iwai <tiwai@suse.de>
* ALSA: pcm: Call directly the common read/write helpersTakashi Iwai2017-06-021-101/+55
| | | | | | | | | | Make snd_pcm_lib_read() and *_write() static inline functions that call the common helper functions directly. This reduces a slight amount of codes, and at the same time, it's a preparation for the further cleanups / fixes. Reviewed-by: Takashi Sakamoto <o-takashi@sakamocchi.jp> Signed-off-by: Takashi Iwai <tiwai@suse.de>
* ALSA: pcm: Shuffle codesTakashi Iwai2017-06-021-106/+106
| | | | | | | Just shuffle the codes, without any change otherwise. Reviewed-by: Takashi Sakamoto <o-takashi@sakamocchi.jp> Signed-off-by: Takashi Iwai <tiwai@suse.de>
* ALSA: pcm: Check PCM state by a common helper functionTakashi Iwai2017-06-021-52/+29
| | | | | Reviewed-by: Takashi Sakamoto <o-takashi@sakamocchi.jp> Signed-off-by: Takashi Iwai <tiwai@suse.de>
* ALSA: pcm: Drop the old copy and silence opsTakashi Iwai2017-06-021-37/+1
| | | | | | | | Now that all users of old copy and silence ops have been converted to the new PCM ops, the old stuff can be retired and go away. Reviewed-by: Takashi Sakamoto <o-takashi@sakamocchi.jp> Signed-off-by: Takashi Iwai <tiwai@suse.de>
* ALSA: pcm: Introduce copy_user, copy_kernel and fill_silence opsTakashi Iwai2017-06-021-15/+74
| | | | | | | | | | | | | | | | | | | | | | | | | | | | For supporting the explicit in-kernel copy of PCM buffer data, and also for further code refactoring, three new PCM ops, copy_user, copy_kernel and fill_silence, are introduced. The old copy and silence ops will be deprecated and removed later once when all callers are converted. The copy_kernel ops is the new one, and it's supposed to transfer the PCM data from the given kernel buffer to the hardware ring-buffer (or vice-versa depending on the stream direction), while the copy_user ops is equivalent with the former copy ops, to transfer the data from the user-space buffer. The major difference of the new copy_* and fill_silence ops from the previous ops is that the new ops take bytes instead of frames for size and position arguments. It has two merits: first, it allows the callback implementation often simpler (just call directly memcpy() & co), and second, it may unify the implementations of both interleaved and non-interleaved cases, as we'll see in the later patch. As of this stage, copy_kernel ops isn't referred yet, but only copy_user is used. Reviewed-by: Takashi Sakamoto <o-takashi@sakamocchi.jp> Acked-by: Mark Brown <broonie@kernel.org> Signed-off-by: Takashi Iwai <tiwai@suse.de>
* ALSA: pcm: add local header file for snd-pcm moduleTakashi Sakamoto2017-05-261-0/+2
| | | | | | | | | | | | | | Several files are used to construct PCM core module, a.k.a snd-pcm. Although available APIs are described in 'include/sound/pcm.h', some of them are not exported as symbols in kernel space. Such APIs are just for module local usage. This commit adds module local header file and move some function prototypes into it so that scopes of them are controlled properly and developers get no confusion from unavailable symbols. Signed-off-by: Takashi Sakamoto <o-takashi@sakamocchi.jp> Signed-off-by: Takashi Iwai <tiwai@suse.de>
* ALSA: pcm: constify function local and read-only tableTakashi Sakamoto2017-05-171-2/+3
| | | | | | | | | | | In a function snd_pcm_hw_params_choose(), target parameters are arranged into a table. Though each entry of this table is read-only, they don't have const qualifier. This commit adds the qualifier. Signed-off-by: Takashi Sakamoto <o-takashi@sakamocchi.jp> Signed-off-by: Takashi Iwai <tiwai@suse.de>
* ALSA: pcm: use helper function to refer parameter as read-onlyTakashi Sakamoto2017-05-171-1/+2
| | | | | | | | | | ALSA pcm core has hw_param_interval_c() to pick up parameter with const qualifier for safe programming. This commit applies it to the cases. Signed-off-by: Takashi Sakamoto <o-takashi@sakamocchi.jp> Signed-off-by: Takashi Iwai <tiwai@suse.de>
* sched/headers: Prepare to move signal wakeup & sigpending methods from ↵Ingo Molnar2017-03-021-0/+1
| | | | | | | | | | | | | <linux/sched.h> into <linux/sched/signal.h> Fix up affected files that include this signal functionality via sched.h. Acked-by: Linus Torvalds <torvalds@linux-foundation.org> Cc: Mike Galbraith <efault@gmx.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: linux-kernel@vger.kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
* ALSA: pcm: Bail out when chmap is already presentTakashi Iwai2016-05-101-0/+2
| | | | | | | | | | | | | | | | When snd_pcm_add_chmap_ctls() is called to the PCM stream to which a chmap has been already assigned, it returns as an error due to the conflicting snd_ctl_add() result. However, this also clears the already assigned chmap_kctl field via pcm_chmap_ctl_private_free(), and becomes inconsistent in the later operation. This patch adds the check of the conflicting chmap kctl before actually trying to allocate / assign. The check failure is treated as a kernel warning, as the double call of snd_pcm_add_chmap_ctls() is basically a driver bug and having the stack trace would help developers to figure out the bad code path. Signed-off-by: Takashi Iwai <tiwai@suse.de>
* ALSA: pcm : Call kill_fasync() in stream lockTakashi Iwai2016-04-141-1/+1
| | | | | | | | | | | | | | | | | | | | | Currently kill_fasync() is called outside the stream lock in snd_pcm_period_elapsed(). This is potentially racy, since the stream may get released even during the irq handler is running. Although snd_pcm_release_substream() calls snd_pcm_drop(), this doesn't guarantee that the irq handler finishes, thus the kill_fasync() call outside the stream spin lock may be invoked after the substream is detached, as recently reported by KASAN. As a quick workaround, move kill_fasync() call inside the stream lock. The fasync is rarely used interface, so this shouldn't have a big impact from the performance POV. Ideally, we should implement some sync mechanism for the proper finish of stream and irq handler. But this oneliner should suffice for most cases, so far. Reported-by: Baozeng Ding <sploving1@gmail.com> Signed-off-by: Takashi Iwai <tiwai@suse.de>
* ALSA: pcm: Avoid "BUG:" string for warnings againTakashi Iwai2016-03-101-1/+1
| | | | | | | | | | | | | The commit [d507941beb1e: ALSA: pcm: Correct PCM BUG error message] made the warning prefix back to "BUG:" due to its previous wrong prefix. But a kernel message containing "BUG:" seems taken as an Oops message wrongly by some brain-dead daemons, and it annoys users in the end. Instead of teaching daemons, change the string again to a more reasonable one. Fixes: 507941beb1e ('ALSA: pcm: Correct PCM BUG error message') Cc: <stable@vger.kernel.org> # v3.19+ Signed-off-by: Takashi Iwai <tiwai@suse.de>
* ALSA: Constify ratden/ratnum constraintsLars-Peter Clausen2015-10-281-8/+9
| | | | | | | | | | | The ALSA core does not modify the constraints provided by a driver. Most constraint helper functions already take a const pointer to the constraint description, the exception at the moment being the ratden and ratnum constraints. Make those const as well, this allows a driver to declare them as const. Signed-off-by: Lars-Peter Clausen <lars@metafoo.de> Signed-off-by: Takashi Iwai <tiwai@suse.de>
* ALSA: Remove transfer_ack_{begin,end} callbacks from struct snd_pcm_runtimeLars-Peter Clausen2015-10-221-5/+0
| | | | | | | | | | | | | | While there is nothing wrong with the transfer_ack_begin and transfer_ack_end callbacks per-se, the last documented user was part of the alsa-driver 0.5.12a package, which was released 14 years ago and even predates the upstream integration of the ALSA core and has subsequently been superseded by newer alsa-driver releases. This seems to indicate that there is no need for having these callbacks and they are just cruft that can be removed. Signed-off-by: Lars-Peter Clausen <lars@metafoo.de> Signed-off-by: Takashi Iwai <tiwai@suse.de>
* ALSA: timer: add config item to export PCM timer disabling for expertJie Yang2015-10-161-0/+2
| | | | | | | | | | | | | | | | PCM timer is not always used. For embedded device, we need an interface to disable it when it is not needed, to shrink the kernel size and memory footprint, here add CONFIG_SND_PCM_TIMER for it. When both CONFIG_SND_PCM_TIMER and CONFIG_SND_TIMER is unselected, about 25KB saving bonus we can get. Please be noted that when disabled, those stubs who using pcm timer (e.g. dmix, dsnoop & co) may work incorrectlly. Suggested-by: Takashi Iwai <tiwai@suse.de> Signed-off-by: Jie Yang <yang.jie@intel.com> Signed-off-by: Takashi Iwai <tiwai@suse.de>
* ALSA: pcm: Modify double acknowledged interrupts check conditionKoro Chen2015-05-191-1/+1
| | | | | | | | | | | | | | | | | Currently in snd_pcm_update_hw_ptr0 during interrupt, we consider there were double acknowledged interrupts when: 1. HW reported pointer is smaller than expected, and 2. Time from last update time (hdelta) is over half a buffer time. However, when HW reported pointer is only a few bytes smaller than expected, and when hdelta is just a little larger than half a buffer time (e.g. ping-pong buffer), it wrongly treats this IRQ as double acknowledged. The condition #2 uses jiffies, but jiffies is not high resolution since it is integer. We should consider jiffies inaccuracy. Signed-off-by: Koro Chen <koro.chen@mediatek.com> Signed-off-by: Takashi Iwai <tiwai@suse.de>
* ALSA: core: add .get_time_infoPierre-Louis Bossart2015-02-201-29/+59
| | | | | | | | | | | Introduce more generic .get_time_info to retrieve system timestamp and audio timestamp in single routine. Backwards compatibility is preserved with same functionality as with .wall_clock method (to be removed in following commits to avoid breaking git bisect) Signed-off-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com> Signed-off-by: Takashi Iwai <tiwai@suse.de>
* Merge tag 'asoc-v3.20-2' of ↵Takashi Iwai2015-02-051-0/+85
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/broonie/sound into for-next ASoC: Updates for v3.20 More updates for v3.20: - Lots of refactoring from Lars-Peter Clausen, moving drivers to more data driven initialization and rationalizing a lot of DAPM usage. - Much improved handling of CDCLK clocks on Samsung I2S controllers. - Lots of driver specific cleanups and feature improvements. - CODEC support for TI PCM514x and TLV320AIC3104 devices. - Board support for Tegra systems with Realtek RT5677. Conflicts: sound/soc/intel/sst-mfld-platform-pcm.c
| * ALSA: pcm: Add snd_interval_ranges() and snd_pcm_hw_constraint_ranges()Peter Rosin2015-01-281-0/+85
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Add helper functions to allow drivers to specify several disjoint ranges for a variable. In particular, there is a codec (PCM512x) that has a hole in its supported range of rates, due to PLL and divider restrictions. This is like snd_pcm_hw_constraint_list(), but for ranges instead of points. Signed-off-by: Peter Rosin <peda@axentia.se> Reviewed-by: Lars-Peter Clausen <lars@metafoo.de> Reviewed-by: Takashi Iwai <tiwai@suse.de> Signed-off-by: Mark Brown <broonie@kernel.org>
* | ALSA: Add support for wildcard msbits constraintsLars-Peter Clausen2014-12-301-1/+12
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Currently the msbits constraints requires to specify a specific sample format width for which the constraint should be applied. But often the number of most significant bits is not sample format specific, but rather a absolute limit. E.g. the PCM interface might accept 32-bit and 24-bit samples, but the DAC has a 16-bit resolution and throws away the LSBs. In this case for both 32-bit and 24-bit format msbits should be set to 16. This patch extends snd_pcm_hw_constraint_msbits() so that a wildcard constraint can be setup that is applied for all formats with a sample width larger than the specified msbits. Choosing the wildcard constraint is done by setting the sample width parameter of the function to 0. Signed-off-by: Lars-Peter Clausen <lars@metafoo.de> Signed-off-by: Takashi Iwai <tiwai@suse.de>
* | ALSA: Fix handling of multiple msbits constraints on the same runtimeLars-Peter Clausen2014-12-301-1/+1
|/ | | | | | | | | | | | | If the sound card is made up of discrete components, each with their own driver (e.g. like in the ASoC case), we might end up with multiple msbits constraint rules installed. Currently this will result in msbits being set to whatever the last rule set it to. This patch updates the behavior of the rule to choose the minimum (other than zero) of all the installed rules. Signed-off-by: Lars-Peter Clausen <lars@metafoo.de> Signed-off-by: Takashi Iwai <tiwai@suse.de>
* ALSA: pcm: Replace PCM hwptr tracking with tracepointsTakashi Iwai2014-11-041-122/+24
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | ALSA PCM core has a mechanism tracking the PCM hwptr updates for analyzing XRUNs. But its log is limited (up to 10) and its log output is a kernel message, which is hard to handle. In this patch, the hwptr logging is moved to the tracing infrastructure instead of its own. Not only the hwptr updates but also XRUN and hwptr errors are recorded on the trace log, so that user can see such events at the exact timing. The new "snd_pcm" entry will appear in the tracing events: # ls -F /sys/kernel/debug/tracing/events/snd_pcm enable filter hw_ptr_error/ hwptr/ xrun/ The hwptr is for the regular hwptr update events. An event trace looks like: aplay-26187 [004] d..3 4012.834761: hwptr: pcmC0D0p/sub0: POS: pos=488, old=0, base=0, period=1024, buf=16384 "POS" shows the hwptr update by the explicit position update call and "IRQ" means the hwptr update by the interrupt, i.e. snd_pcm_period_elapsed() call. The "pos" is the passed ring-buffer offset by the caller, "old" is the previous hwptr, "base" is the hwptr base position, "period" and "buf" are period- and buffer-size of the target PCM substream. (Note that the hwptr position displayed here isn't the ring-buffer offset. It increments up to the PCM position boundary.) The XRUN event appears similarly, but without "pos" field. The hwptr error events appear with the PCM identifier and its reason string, such as "Lost interrupt?". The XRUN and hwptr error reports on kernel message are still left, can be turned on/off via xrun_debug proc like before. But the bit 3, 4, 5 and 6 bits of xrun_debug proc are dropped by this patch. Also, along with the change, the message strings have been reformatted to be a bit more consistent. Last but not least, the hwptr reporting is enabled only when CONFIG_SND_PCM_XRUN_DEBUG is set. Signed-off-by: Takashi Iwai <tiwai@suse.de>
* ALSA: pcm: Correct PCM BUG error messageTakashi Iwai2014-11-041-1/+1
| | | | | | | | While converting to dev_*(), the message showing the invalid PCM position was wrongly tagged as if an XRUN although it's actually a BUG. This patch corrects the message again. Signed-off-by: Takashi Iwai <tiwai@suse.de>
* Merge tag 'asoc-v3.18' of ↵Takashi Iwai2014-10-061-3/+5
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/broonie/sound into for-next ASoC: Updates for v3.18 - More componentisation work from Lars-Peter, this time mainly cleaning up the suspend and bias level transition callbacks. - Real system support for the Intel drivers and a bunch of fixes and enhancements for the associated CODEC drivers, this is going to need a lot quirks over time due to the lack of any firmware description of the boards. - Jack detect support for simple card from Dylan Reid. - A bunch of small fixes and enhancements for the Freescale drivers. - New drivers for Analog Devices SSM4567, Cirrus Logic CS35L32, Everest Semiconductor ES8328 and Freescale cards using the ASRC in newer i.MX processors.
| * ALSA: pcm: fix fifo_size frame calculationClemens Ladisch2014-09-221-3/+5
| | | | | | | | | | | | | | | | | | | | | | | | | | The calculated frame size was wrong because snd_pcm_format_physical_width() actually returns the number of bits, not bytes. Use snd_pcm_format_size() instead, which not only returns bytes, but also simplifies the calculation. Fixes: 8bea869c5e56 ("ALSA: PCM midlevel: improve fifo_size handling") Signed-off-by: Clemens Ladisch <clemens@ladisch.de> Cc: <stable@vger.kernel.org> Signed-off-by: Takashi Iwai <tiwai@suse.de>
* | ALSA: pcm: snd_interval_step: fix changes of open intervalsClemens Ladisch2014-09-081-0/+2
| | | | | | | | | | | | | | | | Changing an interval boundary to a multiple of the step size makes that boundary exact. Signed-off-by: Clemens Ladisch <clemens@ladisch.de> Signed-off-by: Takashi Iwai <tiwai@suse.de>
* | ALSA: pcm: snd_interval_step: drop the min parameterClemens Ladisch2014-09-081-4/+4
|/ | | | | | | | The min parameter was not used by any caller. And if it were used, underflows in the calculations could lead to incorrect results. Signed-off-by: Clemens Ladisch <clemens@ladisch.de> Signed-off-by: Takashi Iwai <tiwai@suse.de>
* ALSA: pcm: 'BUG:' message unnecessarily triggers kerneloopsTim Gardner2014-04-161-1/+1
| | | | | | | | | | | | BugLink: http://bugs.launchpad.net/bugs/1305480 The kerneloops-daemon scans dmesg for common crash signatures, among which is 'BUG:'. The message emitted by the PCM library is really a warning, so the most expedient thing to do seems to be to change the string. Signed-off-by: Tim Gardner <tim.gardner@canonical.com> Signed-off-by: Takashi Iwai <tiwai@suse.de>
* Merge tag 'asoc-v3.15' of ↵Takashi Iwai2014-03-131-0/+1
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/broonie/sound into for-next ASoC: Updates for v3.15 Quite a busy release for ASoC this time, more on janitorial work than exciting new features but welcome nontheless: - Lots of cleanups from Takashi for enumerations; the original API for these was error prone so he's refactored lots of code to use more modern APIs which avoid issues. - Elimination of the ASoC level wrappers for I2C and SPI moving us closer to converting to regmap completely and avoiding some randconfig hassle. - Provide both manually and transparently locked DAPM APIs rather than a mix of the two fixing some concurrency issues. - Start converting CODEC drivers to use separate bus interface drivers rather than having them all in one file helping avoid dependency issues. - DPCM support for Intel Haswell and Bay Trail platforms. - Lots of work on improvements for simple-card, DaVinci and the Renesas rcar drivers. - New drivers for Analog Devices ADAU1977, TI PCM512x and parts of the CSR SiRF SoC.
| * ALSA: Export snd_pcm_constraint_mask64()Mark Brown2014-02-201-0/+1
| | | | | | | | | | | | | | | | | | Allow modules to use it, fixing a build failure when the newly added ADAU1977 driver is built as a module. Reported-by: Stephen Rothwell <sfr@canb.auug.org.au> Signed-off-by: Mark Brown <broonie@linaro.org> Acked-by: Takashi Iwai <tiwai@suse.de>
* | ALSA: pcm: Use standard printk helpersTakashi Iwai2014-02-141-14/+13
|/ | | | | | | | | Use dev_err() & co as much as possible. If not available (no device assigned at the calling point), use pr_xxx() helpers instead. For simplicity, introduce new helpers for pcm stream, pcm_err(), etc. Signed-off-by: Takashi Iwai <tiwai@suse.de>
* ALSA: Add SNDRV_PCM_STATE_PAUSED case in wait_for_avail functionJongHo Kim2013-12-171-0/+2
| | | | | | | | | | | When the process is sleeping at the SNDRV_PCM_STATE_PAUSED state from the wait_for_avail function, the sleep process will be woken by timeout(10 seconds). Even if the sleep process wake up by timeout, by this patch, the process will continue with sleep and wait for the other state. Signed-off-by: JongHo Kim <furmuwon@gmail.com> Cc: <stable@vger.kernel.org> Signed-off-by: Takashi Iwai <tiwai@suse.de>
* ALSA: pcm: Use snd_printd_ratelimit()Tim Gardner2013-08-191-2/+2
| | | | | | | | | | | | | | | | | | | | | The use of snd_printd_ratelimit() supresses superfluous output from printk_ratelimit() when CONFIG_SND_DEBUG is not defined. For example, [ 43.753692] snd_pcm_update_hw_ptr0: 26 callbacks suppressed [ 48.822131] snd_pcm_update_hw_ptr0: 25 callbacks suppressed [ 53.894953] snd_pcm_update_hw_ptr0: 25 callbacks suppressed [ 58.997761] snd_pcm_update_hw_ptr0: 25 callbacks suppressed [ 64.100952] snd_pcm_update_hw_ptr0: 25 callbacks suppressed fills the log even when no debug output is actually produced. Cc: Jaroslav Kysela <perex@perex.cz> Cc: Takashi Iwai <tiwai@suse.de> Cc: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com> Cc: Lars-Peter Clausen <lars@metafoo.de> Cc: Yacine Belkadi <yacine.belkadi.1@gmail.com> Signed-off-by: Tim Gardner <tim.gardner@canonical.com> Signed-off-by: Takashi Iwai <tiwai@suse.de>
* ALSA: Constify the snd_pcm_substream struct ops fieldLars-Peter Clausen2013-05-241-1/+2
| | | | | | | | | The ops field of the snd_pcm_substream struct is never modified inside the ALSA core. Making it const allows drivers to declare their snd_pcm_ops struct as const. Signed-off-by: Lars-Peter Clausen <lars@metafoo.de> Signed-off-by: Takashi Iwai <tiwai@suse.de>
* ALSA: add/change some comments describing function return valuesYacine Belkadi2013-03-121-11/+43
| | | | | | | | | | | | | | | | | | | script/kernel-doc reports the following type of warnings (when run in verbose mode): Warning(sound/core/init.c:152): No description found for return value of 'snd_card_create' To fix that: - add missing descriptions of function return values - use "Return:" sections to describe those return values Along the way: - complete some descriptions - fix some typos Signed-off-by: Yacine Belkadi <yacine.belkadi.1@gmail.com> Signed-off-by: Takashi Iwai <tiwai@suse.de>
* ALSA: core: add hooks for audio timestampsPierre-Louis Bossart2012-10-231-2/+30
| | | | | | | | | | | | | | | | | | | ALSA did not provide any direct means to infer the audio time for A/V sync and system/audio time correlations (eg. PulseAudio). Applications had to track the number of samples read/written and add/subtract the number of samples queued in the ring buffer. This accounting led to small errors, typically several samples, due to the two-step process. Computing the audio time in the kernel is more direct, as all the information is available in the same routines. Also add new .audio_wallclock routine to enable fine-grain synchronization between monotonic system time and audio hardware time. Using the wallclock, if supported in hardware, allows for a much better sub-microsecond precision and a common drift tracking for all devices sharing the same wall clock (master clock). Signed-off-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com> Signed-off-by: Takashi Iwai <tiwai@suse.de>
* ALSA: core: keep track of boundary wrap-aroundPierre-Louis Bossart2012-10-231-5/+20
| | | | | | | | | | Keep track of boundary crossing when hw_ptr exceeds boundary limit and wraps-around. This will help keep track of total number of frames played/received at the kernel level Signed-off-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com> Signed-off-by: Takashi Iwai <tiwai@suse.de>
* ALSA: Fix leftover chmap UNKNOWN -> MONO conversionsTakashi Iwai2012-09-131-2/+2
| | | | | | | A few files have been slipped from the previous commit to add MONO channel type. Signed-off-by: Takashi Iwai <tiwai@suse.de>
* ALSA: pcm - Use UNKNOWN chmap for mono streamsTakashi Iwai2012-09-111-2/+2
| | | | | | | In general, mono streams have no dedicated speaker assignment, thus they should be rather marked as UNKNOWN position. Signed-off-by: Takashi Iwai <tiwai@suse.de>
* ALSA: Remove VOLATILE flag from chmap ctlsTakashi Iwai2012-09-061-1/+0
| | | | | | | | | | The VOLATILE flag was added to control elements by snd_pcm_add_chmap_ctls() just because I didn't want to have a side-effect of "alsactl restore". But now the set operation doesn't allow to change the value unless the PCM stream is in PREAPRED state, there is no reason to keep this flag. Let's rip it off. Signed-off-by: Takashi Iwai <tiwai@suse.de>
* ALSA: PCM: channel mapping API implementationTakashi Iwai2012-09-061-0/+215
| | | | | | | | | | | | | | | | | | This patch implements the basic data types for the standard channel mapping API handling. - The definitions of the channel positions and the new TLV types are added in sound/asound.h and sound/tlv.h, so that they can be referred from user-space. - Introduced a new helper function snd_pcm_add_chmap_ctls() to create control elements representing the channel maps for each PCM (sub)stream. - Some standard pre-defined channel maps are provided for convenience. Signed-off-by: Takashi Iwai <tiwai@suse.de>
* ALSA: pcm: Make constraints lists constMark Brown2012-07-051-2/+2
| | | | | | | They aren't modified by the core so the drivers can declare them const. Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com> Signed-off-by: Takashi Iwai <tiwai@suse.de>
* ALSA: core: group read of pointer, tstamp and jiffiesPierre-Louis Bossart2012-05-231-5/+18
| | | | | | | | | | Group read of hw_ptr, tstamp and jiffies in a sequence for better correlation. Previous code took timestamp at the end, which could introduce delays between audio time and system time. Signed-off-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com> Signed-off-by: Takashi Iwai <tiwai@suse.de>
* ALSA: pcm - Optimize the call of snd_pcm_update_hw_ptr() in read/write loopTakashi Iwai2012-05-111-8/+10
| | | | | | | | | | | | | | | | | | | | | | In the PCM read/write loop, the driver calls snd_pcm_update_hw_ptr() at each time at the beginning of the loop. Russell King reported that this hogs CPU significantly. The current code assumes that the pointer callback is very fast and cheap, also not too much fine grained. It's not true in all cases. When the pointer advances short samples while the read/write copy has been performed, the driver updates the hw_ptr and gets avail > 0 again. Then it tries to read/write these small chunks. This repeats until the avail really gets to zero. For avoiding this situation, a simple workaround is to call snd_pcm_update_hw_ptr() only once at starting the loop, assuming that the read/write copy is performed fast enough. If the available count becomes short, it goes to snd_pcm_wait_avail() anyway, and this processes right. Tested-by: Russell King <rmk+kernel@arm.linux.org.uk> Signed-off-by: Takashi Iwai <tiwai@suse.de>
* ALSA: pcm: Constify the list in snd_pcm_hw_constraint_listMark Brown2012-03-151-1/+2
| | | | | | | | | Allows the constraint lists to be declared const by drivers which seems reasonable; there's plenty of other constification we could do if we were being complete but this was easy and quick. Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com> Signed-off-by: Takashi Iwai <tiwai@suse.de>
* sound: Add export.h for THIS_MODULE/EXPORT_SYMBOL where neededPaul Gortmaker2011-10-311-0/+1
| | | | | | | | These aren't modules, but they do make use of these macros, so they will need export.h to get that definition. Previously, they got it via the implicit module.h inclusion. Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
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