From 93c313dc4fc78b077bb0911afe3a77ffa845ad58 Mon Sep 17 00:00:00 2001 From: Anton Yakovlev Date: Tue, 2 Mar 2021 17:47:06 +0100 Subject: [PATCH] ALSA: virtio: PCM substream operators Introduce the operators required for the operation of substreams. Signed-off-by: Anton Yakovlev Link: https://lore.kernel.org/r/20210302164709.3142702-7-anton.yakovlev@opensynergy.com Signed-off-by: Takashi Iwai Signed-off-by: Vasyl Vavrychuk --- sound/virtio/Makefile | 3 +- sound/virtio/virtio_pcm.c | 2 + sound/virtio/virtio_pcm.h | 5 + sound/virtio/virtio_pcm_ops.c | 445 ++++++++++++++++++++++++++++++++++ 4 files changed, 454 insertions(+), 1 deletion(-) create mode 100644 sound/virtio/virtio_pcm_ops.c diff --git a/sound/virtio/Makefile b/sound/virtio/Makefile index 626af3cc3ed7..34493226793f 100644 --- a/sound/virtio/Makefile +++ b/sound/virtio/Makefile @@ -6,5 +6,6 @@ virtio_snd-objs := \ virtio_card.o \ virtio_ctl_msg.o \ virtio_pcm.o \ - virtio_pcm_msg.o + virtio_pcm_msg.o \ + virtio_pcm_ops.o diff --git a/sound/virtio/virtio_pcm.c b/sound/virtio/virtio_pcm.c index 2dcd763efa29..c10d91fff2fb 100644 --- a/sound/virtio/virtio_pcm.c +++ b/sound/virtio/virtio_pcm.c @@ -470,6 +470,8 @@ int virtsnd_pcm_build_devs(struct virtio_snd *snd) for (kss = ks->substream; kss; kss = kss->next) vs->substreams[kss->number]->substream = kss; + + snd_pcm_set_ops(vpcm->pcm, i, &virtsnd_pcm_ops); } snd_pcm_set_managed_buffer_all(vpcm->pcm, diff --git a/sound/virtio/virtio_pcm.h b/sound/virtio/virtio_pcm.h index 6722f1139666..efd0228746cf 100644 --- a/sound/virtio/virtio_pcm.h +++ b/sound/virtio/virtio_pcm.h @@ -29,6 +29,8 @@ struct virtio_pcm_msg; * @hw_ptr: Substream hardware pointer value in bytes [0 ... buffer_bytes). * @xfer_enabled: Data transfer state (0 - off, 1 - on). * @xfer_xrun: Data underflow/overflow state (0 - no xrun, 1 - xrun). + * @stopped: True if the substream is stopped and must be released on the device + * side. * @msgs: Allocated I/O messages. * @nmsgs: Number of allocated I/O messages. * @msg_last_enqueued: Index of the last I/O message added to the virtqueue. @@ -49,6 +51,7 @@ struct virtio_pcm_substream { size_t hw_ptr; bool xfer_enabled; bool xfer_xrun; + bool stopped; struct virtio_pcm_msg **msgs; unsigned int nmsgs; int msg_last_enqueued; @@ -80,6 +83,8 @@ struct virtio_pcm { struct virtio_pcm_stream streams[SNDRV_PCM_STREAM_LAST + 1]; }; +extern const struct snd_pcm_ops virtsnd_pcm_ops; + int virtsnd_pcm_validate(struct virtio_device *vdev); int virtsnd_pcm_parse_cfg(struct virtio_snd *snd); diff --git a/sound/virtio/virtio_pcm_ops.c b/sound/virtio/virtio_pcm_ops.c new file mode 100644 index 000000000000..0682a2df6c8c --- /dev/null +++ b/sound/virtio/virtio_pcm_ops.c @@ -0,0 +1,445 @@ +// SPDX-License-Identifier: GPL-2.0+ +/* + * virtio-snd: Virtio sound device + * Copyright (C) 2021 OpenSynergy GmbH + */ +#include + +#include "virtio_card.h" + +/* + * I/O messages lifetime + * --------------------- + * + * Allocation: + * Messages are initially allocated in the ops->hw_params() after the size and + * number of periods have been successfully negotiated. + * + * Freeing: + * Messages can be safely freed after the queue has been successfully flushed + * (RELEASE command in the ops->sync_stop()) and the ops->hw_free() has been + * called. + * + * When the substream stops, the ops->sync_stop() waits until the device has + * completed all pending messages. This wait can be interrupted either by a + * signal or due to a timeout. In this case, the device can still access + * messages even after calling ops->hw_free(). It can also issue an interrupt, + * and the interrupt handler will also try to access message structures. + * + * Therefore, freeing of already allocated messages occurs: + * + * - in ops->hw_params(), if this operator was called several times in a row, + * or if ops->hw_free() failed to free messages previously; + * + * - in ops->hw_free(), if the queue has been successfully flushed; + * + * - in dev->release(). + */ + +/* Map for converting ALSA format to VirtIO format. */ +struct virtsnd_a2v_format { + snd_pcm_format_t alsa_bit; + unsigned int vio_bit; +}; + +static const struct virtsnd_a2v_format g_a2v_format_map[] = { + { SNDRV_PCM_FORMAT_IMA_ADPCM, VIRTIO_SND_PCM_FMT_IMA_ADPCM }, + { SNDRV_PCM_FORMAT_MU_LAW, VIRTIO_SND_PCM_FMT_MU_LAW }, + { SNDRV_PCM_FORMAT_A_LAW, VIRTIO_SND_PCM_FMT_A_LAW }, + { SNDRV_PCM_FORMAT_S8, VIRTIO_SND_PCM_FMT_S8 }, + { SNDRV_PCM_FORMAT_U8, VIRTIO_SND_PCM_FMT_U8 }, + { SNDRV_PCM_FORMAT_S16_LE, VIRTIO_SND_PCM_FMT_S16 }, + { SNDRV_PCM_FORMAT_U16_LE, VIRTIO_SND_PCM_FMT_U16 }, + { SNDRV_PCM_FORMAT_S18_3LE, VIRTIO_SND_PCM_FMT_S18_3 }, + { SNDRV_PCM_FORMAT_U18_3LE, VIRTIO_SND_PCM_FMT_U18_3 }, + { SNDRV_PCM_FORMAT_S20_3LE, VIRTIO_SND_PCM_FMT_S20_3 }, + { SNDRV_PCM_FORMAT_U20_3LE, VIRTIO_SND_PCM_FMT_U20_3 }, + { SNDRV_PCM_FORMAT_S24_3LE, VIRTIO_SND_PCM_FMT_S24_3 }, + { SNDRV_PCM_FORMAT_U24_3LE, VIRTIO_SND_PCM_FMT_U24_3 }, + { SNDRV_PCM_FORMAT_S20_LE, VIRTIO_SND_PCM_FMT_S20 }, + { SNDRV_PCM_FORMAT_U20_LE, VIRTIO_SND_PCM_FMT_U20 }, + { SNDRV_PCM_FORMAT_S24_LE, VIRTIO_SND_PCM_FMT_S24 }, + { SNDRV_PCM_FORMAT_U24_LE, VIRTIO_SND_PCM_FMT_U24 }, + { SNDRV_PCM_FORMAT_S32_LE, VIRTIO_SND_PCM_FMT_S32 }, + { SNDRV_PCM_FORMAT_U32_LE, VIRTIO_SND_PCM_FMT_U32 }, + { SNDRV_PCM_FORMAT_FLOAT_LE, VIRTIO_SND_PCM_FMT_FLOAT }, + { SNDRV_PCM_FORMAT_FLOAT64_LE, VIRTIO_SND_PCM_FMT_FLOAT64 }, + { SNDRV_PCM_FORMAT_DSD_U8, VIRTIO_SND_PCM_FMT_DSD_U8 }, + { SNDRV_PCM_FORMAT_DSD_U16_LE, VIRTIO_SND_PCM_FMT_DSD_U16 }, + { SNDRV_PCM_FORMAT_DSD_U32_LE, VIRTIO_SND_PCM_FMT_DSD_U32 }, + { SNDRV_PCM_FORMAT_IEC958_SUBFRAME_LE, + VIRTIO_SND_PCM_FMT_IEC958_SUBFRAME } +}; + +/* Map for converting ALSA frame rate to VirtIO frame rate. */ +struct virtsnd_a2v_rate { + unsigned int rate; + unsigned int vio_bit; +}; + +static const struct virtsnd_a2v_rate g_a2v_rate_map[] = { + { 5512, VIRTIO_SND_PCM_RATE_5512 }, + { 8000, VIRTIO_SND_PCM_RATE_8000 }, + { 11025, VIRTIO_SND_PCM_RATE_11025 }, + { 16000, VIRTIO_SND_PCM_RATE_16000 }, + { 22050, VIRTIO_SND_PCM_RATE_22050 }, + { 32000, VIRTIO_SND_PCM_RATE_32000 }, + { 44100, VIRTIO_SND_PCM_RATE_44100 }, + { 48000, VIRTIO_SND_PCM_RATE_48000 }, + { 64000, VIRTIO_SND_PCM_RATE_64000 }, + { 88200, VIRTIO_SND_PCM_RATE_88200 }, + { 96000, VIRTIO_SND_PCM_RATE_96000 }, + { 176400, VIRTIO_SND_PCM_RATE_176400 }, + { 192000, VIRTIO_SND_PCM_RATE_192000 } +}; + +static int virtsnd_pcm_sync_stop(struct snd_pcm_substream *substream); + +/** + * virtsnd_pcm_open() - Open the PCM substream. + * @substream: Kernel ALSA substream. + * + * Context: Process context. + * Return: 0 on success, -errno on failure. + */ +static int virtsnd_pcm_open(struct snd_pcm_substream *substream) +{ + struct virtio_pcm *vpcm = snd_pcm_substream_chip(substream); + struct virtio_pcm_stream *vs = &vpcm->streams[substream->stream]; + struct virtio_pcm_substream *vss = vs->substreams[substream->number]; + + substream->runtime->hw = vss->hw; + substream->private_data = vss; + + snd_pcm_hw_constraint_integer(substream->runtime, + SNDRV_PCM_HW_PARAM_PERIODS); + + vss->stopped = !!virtsnd_pcm_msg_pending_num(vss); + + /* + * If the substream has already been used, then the I/O queue may be in + * an invalid state. Just in case, we do a check and try to return the + * queue to its original state, if necessary. + */ + return virtsnd_pcm_sync_stop(substream); +} + +/** + * virtsnd_pcm_close() - Close the PCM substream. + * @substream: Kernel ALSA substream. + * + * Context: Process context. + * Return: 0. + */ +static int virtsnd_pcm_close(struct snd_pcm_substream *substream) +{ + return 0; +} + +/** + * virtsnd_pcm_dev_set_params() - Set the parameters of the PCM substream on + * the device side. + * @vss: VirtIO PCM substream. + * @buffer_bytes: Size of the hardware buffer. + * @period_bytes: Size of the hardware period. + * @channels: Selected number of channels. + * @format: Selected sample format (SNDRV_PCM_FORMAT_XXX). + * @rate: Selected frame rate. + * + * Context: Any context that permits to sleep. + * Return: 0 on success, -errno on failure. + */ +static int virtsnd_pcm_dev_set_params(struct virtio_pcm_substream *vss, + unsigned int buffer_bytes, + unsigned int period_bytes, + unsigned int channels, + snd_pcm_format_t format, + unsigned int rate) +{ + struct virtio_snd_msg *msg; + struct virtio_snd_pcm_set_params *request; + unsigned int i; + int vformat = -1; + int vrate = -1; + + for (i = 0; i < ARRAY_SIZE(g_a2v_format_map); ++i) + if (g_a2v_format_map[i].alsa_bit == format) { + vformat = g_a2v_format_map[i].vio_bit; + + break; + } + + for (i = 0; i < ARRAY_SIZE(g_a2v_rate_map); ++i) + if (g_a2v_rate_map[i].rate == rate) { + vrate = g_a2v_rate_map[i].vio_bit; + + break; + } + + if (vformat == -1 || vrate == -1) + return -EINVAL; + + msg = virtsnd_pcm_ctl_msg_alloc(vss, VIRTIO_SND_R_PCM_SET_PARAMS, + GFP_KERNEL); + if (!msg) + return -ENOMEM; + + request = virtsnd_ctl_msg_request(msg); + request->buffer_bytes = cpu_to_le32(buffer_bytes); + request->period_bytes = cpu_to_le32(period_bytes); + request->channels = channels; + request->format = vformat; + request->rate = vrate; + + if (vss->features & (1U << VIRTIO_SND_PCM_F_MSG_POLLING)) + request->features |= + cpu_to_le32(1U << VIRTIO_SND_PCM_F_MSG_POLLING); + + if (vss->features & (1U << VIRTIO_SND_PCM_F_EVT_XRUNS)) + request->features |= + cpu_to_le32(1U << VIRTIO_SND_PCM_F_EVT_XRUNS); + + return virtsnd_ctl_msg_send_sync(vss->snd, msg); +} + +/** + * virtsnd_pcm_hw_params() - Set the parameters of the PCM substream. + * @substream: Kernel ALSA substream. + * @hw_params: Hardware parameters. + * + * Context: Process context. + * Return: 0 on success, -errno on failure. + */ +static int virtsnd_pcm_hw_params(struct snd_pcm_substream *substream, + struct snd_pcm_hw_params *hw_params) +{ + struct virtio_pcm_substream *vss = snd_pcm_substream_chip(substream); + struct virtio_device *vdev = vss->snd->vdev; + int rc; + + if (virtsnd_pcm_msg_pending_num(vss)) { + dev_err(&vdev->dev, "SID %u: invalid I/O queue state\n", + vss->sid); + return -EBADFD; + } + + rc = virtsnd_pcm_dev_set_params(vss, params_buffer_bytes(hw_params), + params_period_bytes(hw_params), + params_channels(hw_params), + params_format(hw_params), + params_rate(hw_params)); + if (rc) + return rc; + + /* + * Free previously allocated messages if ops->hw_params() is called + * several times in a row, or if ops->hw_free() failed to free messages. + */ + virtsnd_pcm_msg_free(vss); + + return virtsnd_pcm_msg_alloc(vss, params_periods(hw_params), + params_period_bytes(hw_params)); +} + +/** + * virtsnd_pcm_hw_free() - Reset the parameters of the PCM substream. + * @substream: Kernel ALSA substream. + * + * Context: Process context. + * Return: 0 + */ +static int virtsnd_pcm_hw_free(struct snd_pcm_substream *substream) +{ + struct virtio_pcm_substream *vss = snd_pcm_substream_chip(substream); + + /* If the queue is flushed, we can safely free the messages here. */ + if (!virtsnd_pcm_msg_pending_num(vss)) + virtsnd_pcm_msg_free(vss); + + return 0; +} + +/** + * virtsnd_pcm_prepare() - Prepare the PCM substream. + * @substream: Kernel ALSA substream. + * + * Context: Process context. + * Return: 0 on success, -errno on failure. + */ +static int virtsnd_pcm_prepare(struct snd_pcm_substream *substream) +{ + struct virtio_pcm_substream *vss = snd_pcm_substream_chip(substream); + struct virtio_device *vdev = vss->snd->vdev; + struct virtio_snd_msg *msg; + + if (virtsnd_pcm_msg_pending_num(vss)) { + dev_err(&vdev->dev, "SID %u: invalid I/O queue state\n", + vss->sid); + return -EBADFD; + } + + vss->buffer_bytes = snd_pcm_lib_buffer_bytes(substream); + vss->hw_ptr = 0; + vss->xfer_xrun = false; + vss->msg_last_enqueued = -1; + vss->msg_count = 0; + + msg = virtsnd_pcm_ctl_msg_alloc(vss, VIRTIO_SND_R_PCM_PREPARE, + GFP_KERNEL); + if (!msg) + return -ENOMEM; + + return virtsnd_ctl_msg_send_sync(vss->snd, msg); +} + +/** + * virtsnd_pcm_trigger() - Process command for the PCM substream. + * @substream: Kernel ALSA substream. + * @command: Substream command (SNDRV_PCM_TRIGGER_XXX). + * + * Context: Any context. Takes and releases the VirtIO substream spinlock. + * May take and release the tx/rx queue spinlock. + * Return: 0 on success, -errno on failure. + */ +static int virtsnd_pcm_trigger(struct snd_pcm_substream *substream, int command) +{ + struct virtio_pcm_substream *vss = snd_pcm_substream_chip(substream); + struct virtio_snd *snd = vss->snd; + struct virtio_snd_queue *queue; + struct virtio_snd_msg *msg; + unsigned long flags; + int rc; + + switch (command) { + case SNDRV_PCM_TRIGGER_START: + case SNDRV_PCM_TRIGGER_PAUSE_RELEASE: + queue = virtsnd_pcm_queue(vss); + + spin_lock_irqsave(&queue->lock, flags); + spin_lock(&vss->lock); + rc = virtsnd_pcm_msg_send(vss); + if (!rc) + vss->xfer_enabled = true; + spin_unlock(&vss->lock); + spin_unlock_irqrestore(&queue->lock, flags); + if (rc) + return rc; + + msg = virtsnd_pcm_ctl_msg_alloc(vss, VIRTIO_SND_R_PCM_START, + GFP_KERNEL); + if (!msg) { + spin_lock_irqsave(&vss->lock, flags); + vss->xfer_enabled = false; + spin_unlock_irqrestore(&vss->lock, flags); + + return -ENOMEM; + } + + return virtsnd_ctl_msg_send_sync(snd, msg); + case SNDRV_PCM_TRIGGER_STOP: + vss->stopped = true; + fallthrough; + case SNDRV_PCM_TRIGGER_PAUSE_PUSH: + spin_lock_irqsave(&vss->lock, flags); + vss->xfer_enabled = false; + spin_unlock_irqrestore(&vss->lock, flags); + + msg = virtsnd_pcm_ctl_msg_alloc(vss, VIRTIO_SND_R_PCM_STOP, + GFP_KERNEL); + if (!msg) + return -ENOMEM; + + return virtsnd_ctl_msg_send_sync(snd, msg); + default: + return -EINVAL; + } +} + +/** + * virtsnd_pcm_sync_stop() - Synchronous PCM substream stop. + * @substream: Kernel ALSA substream. + * + * The function can be called both from the upper level or from the driver + * itself. + * + * Context: Process context. Takes and releases the VirtIO substream spinlock. + * Return: 0 on success, -errno on failure. + */ +static int virtsnd_pcm_sync_stop(struct snd_pcm_substream *substream) +{ + struct virtio_pcm_substream *vss = snd_pcm_substream_chip(substream); + struct virtio_snd *snd = vss->snd; + struct virtio_snd_msg *msg; + unsigned int js = msecs_to_jiffies(virtsnd_msg_timeout_ms); + int rc; + + cancel_work_sync(&vss->elapsed_period); + + if (!vss->stopped) + return 0; + + msg = virtsnd_pcm_ctl_msg_alloc(vss, VIRTIO_SND_R_PCM_RELEASE, + GFP_KERNEL); + if (!msg) + return -ENOMEM; + + rc = virtsnd_ctl_msg_send_sync(snd, msg); + if (rc) + return rc; + + /* + * The spec states that upon receipt of the RELEASE command "the device + * MUST complete all pending I/O messages for the specified stream ID". + * Thus, we consider the absence of I/O messages in the queue as an + * indication that the substream has been released. + */ + rc = wait_event_interruptible_timeout(vss->msg_empty, + !virtsnd_pcm_msg_pending_num(vss), + js); + if (rc <= 0) { + dev_warn(&snd->vdev->dev, "SID %u: failed to flush I/O queue\n", + vss->sid); + + return !rc ? -ETIMEDOUT : rc; + } + + vss->stopped = false; + + return 0; +} + +/** + * virtsnd_pcm_pointer() - Get the current hardware position for the PCM + * substream. + * @substream: Kernel ALSA substream. + * + * Context: Any context. Takes and releases the VirtIO substream spinlock. + * Return: Hardware position in frames inside [0 ... buffer_size) range. + */ +static snd_pcm_uframes_t +virtsnd_pcm_pointer(struct snd_pcm_substream *substream) +{ + struct virtio_pcm_substream *vss = snd_pcm_substream_chip(substream); + snd_pcm_uframes_t hw_ptr = SNDRV_PCM_POS_XRUN; + unsigned long flags; + + spin_lock_irqsave(&vss->lock, flags); + if (!vss->xfer_xrun) + hw_ptr = bytes_to_frames(substream->runtime, vss->hw_ptr); + spin_unlock_irqrestore(&vss->lock, flags); + + return hw_ptr; +} + +/* PCM substream operators map. */ +const struct snd_pcm_ops virtsnd_pcm_ops = { + .open = virtsnd_pcm_open, + .close = virtsnd_pcm_close, + .ioctl = snd_pcm_lib_ioctl, + .hw_params = virtsnd_pcm_hw_params, + .hw_free = virtsnd_pcm_hw_free, + .prepare = virtsnd_pcm_prepare, + .trigger = virtsnd_pcm_trigger, + .sync_stop = virtsnd_pcm_sync_stop, + .pointer = virtsnd_pcm_pointer, +};