diff options
Diffstat (limited to 'alsa.c')
| -rwxr-xr-x | alsa.c | 175 |
1 files changed, 0 insertions, 175 deletions
@@ -1,175 +0,0 @@ -// SPDX-License-Identifier: GPL-2.0 -/* - * ALSA Virtual Soundcard - * - * alsa.c - ALSA PCM driver for virtual ALSA card - * - * Copyright (C) 2010-2018 Fiberdyne Systems Pty Ltd - */ - -#include <sound/core.h> -#include <sound/initval.h> - -#include "alsa.h" - -static struct snd_card *card; - -/** - * pcm_constructor - Constructs the ALSA PCM middle devices for this driver - * @card: The snd_card struct to construct the devices for - * @return 0 on success or error code otherwise - */ -static int pcm_constructor(struct snd_card *card) -{ - struct snd_pcm *pcm; - int i; - - // Allocate Playback PCM instances - for (i = 0; i < coreinfo.playback.devices; i++) { - CHK_ERR(snd_pcm_new(card, - coreinfo.playback.config[i].devicename, i, - 1, 0, &pcm)); - - /** Register driver callbacks */ - snd_pcm_set_ops(pcm, SNDRV_PCM_STREAM_PLAYBACK, &pcm_ops); - snd_pcm_set_ops(pcm, SNDRV_PCM_STREAM_CAPTURE, &pcm_ops); - - pcm->info_flags = 0; - strcpy(pcm->name, coreinfo.playback.config[i].devicename); - } - - // Allocate Capture PCM instances - for (i = 0; i < coreinfo.capture.devices; i++) { - CHK_ERR(snd_pcm_new(card, coreinfo.capture.config[i].devicename, - i, 0, 1, &pcm)); - - /** Register driver callbacks */ - snd_pcm_set_ops(pcm, SNDRV_PCM_STREAM_CAPTURE, &pcm_ops); - - pcm->info_flags = 0; - strcpy(pcm->name, coreinfo.capture.config[i].devicename); - } - - return 0; -} - -/** - * alloc_dev_config - Allocates memory for ALSA device configuration - * @return: 0 on success or error code otherwise - */ -static int alloc_dev_config(struct avirt_alsa_devconfig **devconfig, - struct avirt_alsa_devconfig *userconfig, - unsigned int numdevices) -{ - if (numdevices == 0) - return 0; - - *devconfig = kzalloc(sizeof(**devconfig) * numdevices, GFP_KERNEL); - if (!(*devconfig)) - return -ENOMEM; - - memcpy(*devconfig, userconfig, - sizeof(struct avirt_alsa_devconfig) * numdevices); - - return 0; -} - -struct avirt_alsa_group *avirt_alsa_get_group(int direction) -{ - switch (direction) { - case SNDRV_PCM_STREAM_PLAYBACK: - return &coreinfo.playback; - case SNDRV_PCM_STREAM_CAPTURE: - return &coreinfo.capture; - default: - pr_err("[%s] Direction must be SNDRV_PCM_STREAM_XXX!", - __func__); - return NULL; - } -} - -/** - * avirt_alsa_configure_pcm- Configure the PCM device - * @config: Device configuration structure array - * @direction: Direction of PCM (SNDRV_PCM_STREAM_XXX) - * @numdevices: Number of devices (array length) - * @return: 0 on success or error code otherwise - */ -int avirt_alsa_configure_pcm(struct avirt_alsa_devconfig *config, int direction, - unsigned int numdevices) -{ - struct avirt_alsa_group *group; - - group = avirt_alsa_get_group(direction); - CHK_NULL(group); - - CHK_ERR(alloc_dev_config(&group->config, config, numdevices)); - - group->devices = numdevices; - - return 0; -} - -/** - * avirt_alsa_register - Registers the ALSA driver - * @devptr: Platform driver device - * @return: 0 on success or error code otherwise - */ -int avirt_alsa_register(struct platform_device *devptr) -{ - static struct snd_device_ops device_ops; - - // Create the card instance - CHK_ERR_V(snd_card_new(&devptr->dev, SNDRV_DEFAULT_IDX1, "avirt", - THIS_MODULE, 0, &card), - "Failed to create sound card"); - - strcpy(card->driver, "avirt-alsa-device"); - strcpy(card->shortname, "avirt"); - strcpy(card->longname, "A virtual sound card driver for ALSA"); - - // Create new sound device - CHK_ERR_V((snd_device_new(card, SNDRV_DEV_LOWLEVEL, &coreinfo, - &device_ops)), - "Failed to create sound device"); - - CHK_ERR((pcm_constructor(card))); - - /** Register with the ALSA framework */ - CHK_ERR_V(snd_card_register(card), "Device registration failed"); - - return 0; -} - -/** - * avirt_alsa_deregister - Deregisters the ALSA driver - * @devptr: Platform driver device - * @return: 0 on success or error code otherwise - */ -int avirt_alsa_deregister(void) -{ - CHK_NULL(card); - snd_card_free(card); - CHK_NULL(coreinfo.playback.config); - kfree(coreinfo.playback.config); - CHK_NULL(coreinfo.capture.config); - kfree(coreinfo.capture.config); - - return 0; -} - -/** - * pcm_buff_complete_cb - PCM buffer complete callback - * @substreamid: pointer to ALSA PCM substream - * @return 0 on success or error code otherwise - * - * This should be called from a child Audio Path once it has finished processing - * the pcm buffer - */ -int pcm_buff_complete_cb(struct snd_pcm_substream *substream) -{ - // Notify ALSA middle layer of the elapsed period boundary - snd_pcm_period_elapsed(substream); - - return 0; -} |