linux-dev/sound/core/Kconfig, branch master

ALSA: control: Add input validation

2022-06-15T05:45:28Z

This patch adds a new feature to enable the validation of input data to control elements in the ALSA core side. When CONFIG_SND_CTL_INPUT_VALIDATION is set, ALSA core verifies whether the each input value via control API is in the defined ranges, also checks whether it's aligned to the defined steps. If an invalid value is detected, ALSA core returns -EINVAL error immediately without passing further to the driver's callback. So this is a kind of hardening for (badly written) drivers that have no proper error checks, at the cost of a slight performance overhead. Technically seen, this reuses a part of the existing validation code for CONFIG_SND_CTL_DEBUG case with a slight modification to suppress error prints for the input validation. Link: https://lore.kernel.org/r/20220609120219.3937-5-tiwai@suse.de Signed-off-by: Takashi Iwai

ALSA: control: Rename CONFIG_SND_CTL_VALIDATION to CONFIG_SND_CTL_DEBUG

2022-06-15T05:45:27Z

The purpose of CONFIG_SND_CTL_VALIDATION is rather to enable the debugging feature for the control API. The validation is only a part of it. Let's rename it to be more explicit and intuitive. While we're at it, let's advertise, give more comment to recommend this feature for development in the kconfig help text. Link: https://lore.kernel.org/r/20220609120219.3937-3-tiwai@suse.de Signed-off-by: Takashi Iwai

ALSA: control: Use xarray for faster lookups

2022-06-15T05:44:55Z

The control elements are managed in a single linked list and we traverse the whole list for matching each numid or ctl id per every inquiry of a control element. This is OK-ish for a small number of elements but obviously it doesn't scale. Especially the matching with the ctl id takes time because it checks each field of the snd_ctl_id element, e.g. the name string is matched with strcmp(). This patch adds the hash tables with Xarray for improving the lookup speed of a control element. There are two xarray tables added to the card; one for numid and another for ctl id. For the numid, we use the numid as the index, while for the ctl id, we calculate a hash key. The lookup is done via a single xa_load() execution. As long as the given control element is found on the Xarray table, that's fine, we can give back a quick lookup result. The problem is when no entry hits on the table, and for this case, we have a slight optimization. Namely, the driver checks whether we had a collision on Xarray table, and do a fallback search (linear lookup of the full entries) only if a hash key collision happened beforehand. So, in theory, the inquiry for a non-existing element might take still time even with this patch in a worst case, but this must be pretty rare. The feature is enabled via CONFIG_SND_CTL_FAST_LOOKUP, which is turned on as default. For simplicity, the option can be turned off only when CONFIG_EXPERT is set ("You are expert? Then you manage 1000 knobs"). Link: https://lore.kernel.org/r/20211028130027.18764-1-tiwai@suse.de Link: https://lore.kernel.org/r/20220609180504.775-1-tiwai@suse.de Link: https://lore.kernel.org/all/cover.1653813866.git.quic_rbankapu@quicinc.com/ Link: https://lore.kernel.org/r/20220610064537.18660-1-tiwai@suse.de Signed-off-by: Takashi Iwai

ALSA: core: Fix typo in 'PCM Timer Interface' help

2022-03-18T08:19:37Z

Signed-off-by: Elijah Harding Link: https://lore.kernel.org/r/20220318015201.30871-1-eharding830@gmail.com Signed-off-by: Takashi Iwai

ALSA: control - add generic LED trigger module as the new control layer

2021-03-30T13:33:58Z

The recent laptops have usually two LEDs assigned to reflect the speaker and microphone mute state. This implementation adds a tiny layer on top of the control API which calculates the state for those LEDs using the driver callbacks. Two new access flags are introduced to describe the controls which affects the audio path settings (an easy code change for drivers). The LED resource can be shared with multiple sound cards with this code. The user space controls may be added to the state chain on demand, too. This code should replace the LED code in the HDA driver and add a possibility to easy extend the other drivers (ASoC codecs etc.). Signed-off-by: Jaroslav Kysela Link: https://lore.kernel.org/r/20210317172945.842280-4-perex@perex.cz Signed-off-by: Takashi Iwai

ALSA: jack: implement software jack injection via debugfs

2021-02-02T09:37:07Z

This change adds audio jack injection feature through debugfs, with this feature, we could validate alsa userspace changes by injecting plugin or plugout events to the non-phantom audio jacks. With this change, the sound core will build the folders $debugfs_mount_dir/sound/cardN if SND_DEBUG and DEBUG_FS are enabled. And if users also enable the SND_JACK_INJECTION_DEBUG, the jack injection nodes will be built in the folder cardN like below: $tree $debugfs_mount_dir/sound $debugfs_mount_dir/sound ├── card0 │ ├── HDMI_DP_pcm_10_Jack │ │ ├── jackin_inject │ │ ├── kctl_id │ │ ├── mask_bits │ │ ├── status │ │ ├── sw_inject_enable │ │ └── type ... │ └── HDMI_DP_pcm_9_Jack │ ├── jackin_inject │ ├── kctl_id │ ├── mask_bits │ ├── status │ ├── sw_inject_enable │ └── type └── card1 ├── HDMI_DP_pcm_5_Jack │ ├── jackin_inject │ ├── kctl_id │ ├── mask_bits │ ├── status │ ├── sw_inject_enable │ └── type ... ├── Headphone_Jack │ ├── jackin_inject │ ├── kctl_id │ ├── mask_bits │ ├── status │ ├── sw_inject_enable │ └── type └── Headset_Mic_Jack ├── jackin_inject ├── kctl_id ├── mask_bits ├── status ├── sw_inject_enable └── type The nodes kctl_id, mask_bits, status and type are read-only, users could check jack or jack_kctl's information through them. The nodes sw_inject_enable and jackin_inject are directly used for injection. The sw_inject_enable is read-write, users could check if software injection is enabled or not on this jack, and users could echo 1 or 0 to enable or disable software injection on this jack. Once the injection is enabled, the jack will not change by hardware events anymore, once the injection is disabled, the jack will restore the last reported hardware events to the jack. The jackin_inject is write-only, if the injection is enabled, users could echo 1 or 0 to this node to inject plugin or plugout events to this jack. For the detailed usage information on these nodes, please refer to Documentation/sound/designs/jack-injection.rst. Reviewed-by: Takashi Iwai Reviewed-by: Jaroslav Kysela Reviewed-by: Kai Vehmanen Signed-off-by: Hui Wang Link: https://lore.kernel.org/r/20210127085639.74954-2-hui.wang@canonical.com Signed-off-by: Takashi Iwai

ALSA: control: Add verification for kctl accesses

2020-01-04T08:37:59Z

The current implementation of ALSA control API fully relies on the callbacks of each driver, and there is no verification of the values passed via API. This patch is an attempt to improve the situation slightly by adding the validation code for the values stored via info and get callbacks. The patch adds a new kconfig, CONFIG_SND_CTL_VALIDATION. It depends on CONFIG_SND_DEBUG and off as default since the validation would require a slight overhead including the additional call of info callback at each get callback invocation. When this config is enabled, the values stored by each info callback invocation are verified, namely: - Whether the info type is valid - Whether the number of enum items is non-zero - Whether the given info count is within the allowed boundary Similarly, the values stored at each get callback are verified as well: - Whether the values are within the given range - Whether the values are aligned with the given step - Whether any further changes are seen in the data array over the given info count The last point helps identifying a possibly invalid data type access, typically a case where the info callback declares the type being SNDRV_CTL_ELEM_TYPE_ENUMERATED while the get/put callbacks store the values in value.integer.value[] array. When a validation fails, the ALSA core logs an error message including the device and the control ID, and the API call also returns an error. So, with the new validation turned on, the driver behavior difference may be visible on user-space, too -- it's intentional, though, so that we can catch an error more clearly. The patch also introduces a new ctl access type, SNDRV_CTL_ELEM_ACCESS_SKIP_CHECK. A driver may pass this flag with other access bits to indicate that the ctl element won't be verified. It's useful when a driver code is specially written to access the data greater than info->count size by some reason. For example, this flag is actually set now in HD-audio HDMI codec driver which needs to clear the data array in the case of the disconnected monitor. Also, the PCM channel-map helper code is slightly modified to avoid the false-positive hit by this validation code, too. Link: https://lore.kernel.org/r/20200104083556.27789-1-tiwai@suse.de Signed-off-by: Takashi Iwai

sound: Fix Kconfig indentation

2019-10-07T01:53:03Z

Adjust indentation from spaces to tab (+optional two spaces) as in coding style with command like: $ sed -e 's/^ /\t/' -i */Kconfig Signed-off-by: Krzysztof Kozlowski Acked-by: Mark Brown Link: https://lore.kernel.org/r/20191004144931.3851-1-krzk@kernel.org Signed-off-by: Takashi Iwai

treewide: Add SPDX license identifier - Makefile/Kconfig

2019-05-21T08:50:46Z

Add SPDX license identifiers to all Make/Kconfig files which: - Have no license information of any form These files fall under the project license, GPL v2 only. The resulting SPDX license identifier is: GPL-2.0-only Signed-off-by: Thomas Gleixner Signed-off-by: Greg Kroah-Hartman

docs: Fix some broken references

2018-06-15T21:10:01Z

As we move stuff around, some doc references are broken. Fix some of them via this script: ./scripts/documentation-file-ref-check --fix Manually checked if the produced result is valid, removing a few false-positives. Acked-by: Takashi Iwai Acked-by: Masami Hiramatsu Acked-by: Stephen Boyd Acked-by: Charles Keepax Acked-by: Mathieu Poirier Reviewed-by: Coly Li Signed-off-by: Mauro Carvalho Chehab Acked-by: Jonathan Corbet