Re: [PATCH v11 15/15] media: vim2m-audio: add virtual driver for audio memory to memory
From: Shengjiu Wang
Date: Thu Jan 18 2024 - 01:13:40 EST
On Wed, Jan 17, 2024 at 6:32 PM Hans Verkuil <hverkuil@xxxxxxxxx> wrote:
>
> On 22/11/2023 08:23, Shengjiu Wang wrote:
> > Audio memory to memory virtual driver use video memory to memory
> > virtual driver vim2m.c as example. The main difference is
> > device type is VFL_TYPE_AUDIO and device cap type is V4L2_CAP_AUDIO_M2M.
> >
> > The device_run function is a dummy function, which is simply
> > copy the data from input buffer to output buffer.
> >
> > Signed-off-by: Shengjiu Wang <shengjiu.wang@xxxxxxx>
> > ---
> > drivers/media/test-drivers/Kconfig | 11 +
> > drivers/media/test-drivers/Makefile | 1 +
> > drivers/media/test-drivers/vim2m-audio.c | 799 +++++++++++++++++++++++
> > 3 files changed, 811 insertions(+)
> > create mode 100644 drivers/media/test-drivers/vim2m-audio.c
> >
> > diff --git a/drivers/media/test-drivers/Kconfig b/drivers/media/test-drivers/Kconfig
> > index 459b433e9fae..55f8af6ee4e2 100644
> > --- a/drivers/media/test-drivers/Kconfig
> > +++ b/drivers/media/test-drivers/Kconfig
> > @@ -17,6 +17,17 @@ config VIDEO_VIM2M
> > This is a virtual test device for the memory-to-memory driver
> > framework.
> >
> > +config VIDEO_VIM2M_AUDIO
> > + tristate "Virtual Memory-to-Memory Driver For Audio"
> > + depends on VIDEO_DEV
> > + select VIDEOBUF2_VMALLOC
> > + select V4L2_MEM2MEM_DEV
> > + select MEDIA_CONTROLLER
> > + select MEDIA_CONTROLLER_REQUEST_API
>
> Drop this. This option has been removed.
>
> > + help
> > + This is a virtual audio test device for the memory-to-memory driver
> > + framework.
> > +
> > source "drivers/media/test-drivers/vicodec/Kconfig"
> > source "drivers/media/test-drivers/vimc/Kconfig"
> > source "drivers/media/test-drivers/vivid/Kconfig"
> > diff --git a/drivers/media/test-drivers/Makefile b/drivers/media/test-drivers/Makefile
> > index 740714a4584d..0c61c9ada3e1 100644
> > --- a/drivers/media/test-drivers/Makefile
> > +++ b/drivers/media/test-drivers/Makefile
> > @@ -10,6 +10,7 @@ obj-$(CONFIG_DVB_VIDTV) += vidtv/
> >
> > obj-$(CONFIG_VIDEO_VICODEC) += vicodec/
> > obj-$(CONFIG_VIDEO_VIM2M) += vim2m.o
> > +obj-$(CONFIG_VIDEO_VIM2M_AUDIO) += vim2m-audio.o
> > obj-$(CONFIG_VIDEO_VIMC) += vimc/
> > obj-$(CONFIG_VIDEO_VIVID) += vivid/
> > obj-$(CONFIG_VIDEO_VISL) += visl/
> > diff --git a/drivers/media/test-drivers/vim2m-audio.c b/drivers/media/test-drivers/vim2m-audio.c
> > new file mode 100644
> > index 000000000000..72806ada8628
> > --- /dev/null
> > +++ b/drivers/media/test-drivers/vim2m-audio.c
> > @@ -0,0 +1,799 @@
> > +// SPDX-License-Identifier: GPL-2.0+
> > +/*
> > + * A virtual v4l2-mem2mem example for audio device.
> > + */
> > +
> > +#include <linux/module.h>
> > +#include <linux/delay.h>
> > +#include <linux/fs.h>
> > +#include <linux/sched.h>
> > +#include <linux/slab.h>
> > +
> > +#include <linux/platform_device.h>
> > +#include <media/v4l2-mem2mem.h>
> > +#include <media/v4l2-device.h>
> > +#include <media/v4l2-ioctl.h>
> > +#include <media/v4l2-ctrls.h>
> > +#include <media/v4l2-event.h>
> > +#include <media/videobuf2-vmalloc.h>
> > +#include <sound/dmaengine_pcm.h>
> > +
> > +MODULE_DESCRIPTION("Virtual device for audio mem2mem testing");
> > +MODULE_LICENSE("GPL");
> > +
> > +static unsigned int debug;
> > +module_param(debug, uint, 0644);
> > +MODULE_PARM_DESC(debug, "debug level");
> > +
> > +#define MEM2MEM_NAME "vim2m-audio"
> > +
> > +#define dprintk(dev, lvl, fmt, arg...) \
> > + v4l2_dbg(lvl, debug, &(dev)->v4l2_dev, "%s: " fmt, __func__, ## arg)
> > +
> > +#define SAMPLE_NUM 4096
> > +
> > +static void audm2m_dev_release(struct device *dev)
> > +{}
> > +
> > +static struct platform_device audm2m_pdev = {
> > + .name = MEM2MEM_NAME,
> > + .dev.release = audm2m_dev_release,
> > +};
> > +
> > +static u32 formats[] = {
> > + V4L2_AUDIO_FMT_S16_LE,
> > +};
> > +
> > +#define NUM_FORMATS ARRAY_SIZE(formats)
> > +
> > +/* Per-queue, driver-specific private data */
> > +struct audm2m_q_data {
> > + unsigned int rate;
> > + unsigned int channels;
> > + unsigned int buffersize;
> > + unsigned int sequence;
> > + u32 fourcc;
> > +};
> > +
> > +enum {
> > + V4L2_M2M_SRC = 0,
> > + V4L2_M2M_DST = 1,
> > +};
> > +
> > +static snd_pcm_format_t find_format(u32 fourcc)
> > +{
> > + snd_pcm_format_t fmt;
> > + unsigned int k;
> > +
> > + for (k = 0; k < NUM_FORMATS; k++) {
> > + if (formats[k] == fourcc)
> > + break;
> > + }
> > +
> > + if (k == NUM_FORMATS)
> > + return 0;
> > +
> > + fmt = v4l2_fourcc_to_audfmt(formats[k]);
> > +
> > + return fmt;
> > +}
> > +
> > +struct audm2m_dev {
> > + struct v4l2_device v4l2_dev;
> > + struct video_device vfd;
> > +
> > + struct mutex dev_mutex;
> > +
> > + struct v4l2_m2m_dev *m2m_dev;
> > +#ifdef CONFIG_MEDIA_CONTROLLER
> > + struct media_device mdev;
> > +#endif
> > +};
> > +
> > +struct audm2m_ctx {
> > + struct v4l2_fh fh;
> > + struct v4l2_ctrl_handler ctrl_handler;
> > + struct audm2m_dev *dev;
> > +
> > + struct mutex vb_mutex;
> > +
> > + /* Source and destination queue data */
> > + struct audm2m_q_data q_data[2];
> > +};
> > +
> > +static inline struct audm2m_ctx *file2ctx(struct file *file)
> > +{
> > + return container_of(file->private_data, struct audm2m_ctx, fh);
> > +}
> > +
> > +static struct audm2m_q_data *get_q_data(struct audm2m_ctx *ctx,
> > + enum v4l2_buf_type type)
> > +{
> > + if (type == V4L2_BUF_TYPE_AUDIO_OUTPUT)
> > + return &ctx->q_data[V4L2_M2M_SRC];
> > + return &ctx->q_data[V4L2_M2M_DST];
> > +}
> > +
> > +static const char *type_name(enum v4l2_buf_type type)
> > +{
> > + if (type == V4L2_BUF_TYPE_AUDIO_OUTPUT)
> > + return "Output";
> > + return "Capture";
> > +}
> > +
> > +/*
> > + * mem2mem callbacks
> > + */
> > +
> > +/*
> > + * device_run() - prepares and starts the device
> > + */
> > +static void device_run(void *priv)
> > +{
> > + struct audm2m_ctx *ctx = priv;
> > + struct audm2m_dev *audm2m_dev;
> > + struct vb2_v4l2_buffer *src_buf, *dst_buf;
> > + struct audm2m_q_data *q_data_src, *q_data_dst;
> > + int src_size, dst_size = 0;
> > + short *src_addr, *dst_addr;
> > + int i;
> > +
> > + audm2m_dev = ctx->dev;
> > +
> > + q_data_src = get_q_data(ctx, V4L2_BUF_TYPE_AUDIO_OUTPUT);
> > + if (!q_data_src)
> > + return;
> > +
> > + q_data_dst = get_q_data(ctx, V4L2_BUF_TYPE_AUDIO_CAPTURE);
> > + if (!q_data_dst)
> > + return;
> > +
> > + src_buf = v4l2_m2m_next_src_buf(ctx->fh.m2m_ctx);
> > + dst_buf = v4l2_m2m_next_dst_buf(ctx->fh.m2m_ctx);
> > + src_buf->sequence = q_data_src->sequence++;
> > + dst_buf->sequence = q_data_dst->sequence++;
> > + v4l2_m2m_buf_copy_metadata(src_buf, dst_buf, false);
> > +
> > + /* Process the conversion */
> > + src_size = vb2_get_plane_payload(&src_buf->vb2_buf, 0);
> > +
> > + src_addr = vb2_plane_vaddr(&src_buf->vb2_buf, 0);
> > + dst_addr = vb2_plane_vaddr(&dst_buf->vb2_buf, 0);
> > +
> > + if (q_data_src->rate == q_data_dst->rate) {
> > + memcpy(dst_addr, src_addr, src_size);
> > + dst_size = src_size;
> > + } else if (q_data_src->rate == 2 * q_data_dst->rate) {
> > + /* 8k to 16k */
> > + for (i = 0; i < src_size / 2; i++) {
> > + *dst_addr++ = *src_addr++;
> > + src_addr++;
> > + }
> > +
> > + dst_size = src_size / 2;
> > + } else if (q_data_src->rate * 2 == q_data_dst->rate) {
> > + /* 16k to 8k */
> > + for (i = 0; i < src_size / 2; i++) {
> > + *dst_addr++ = *src_addr;
> > + *dst_addr++ = *src_addr++;
> > + }
> > +
> > + dst_size = src_size * 2;
> > + }
> > +
> > + vb2_set_plane_payload(&dst_buf->vb2_buf, 0, dst_size);
> > +
> > + src_buf = v4l2_m2m_src_buf_remove(ctx->fh.m2m_ctx);
> > + dst_buf = v4l2_m2m_dst_buf_remove(ctx->fh.m2m_ctx);
> > +
> > + v4l2_m2m_buf_done(src_buf, VB2_BUF_STATE_DONE);
> > + v4l2_m2m_buf_done(dst_buf, VB2_BUF_STATE_DONE);
> > + v4l2_m2m_job_finish(audm2m_dev->m2m_dev, ctx->fh.m2m_ctx);
> > +}
> > +
> > +static int audm2m_querycap(struct file *file, void *priv,
> > + struct v4l2_capability *cap)
> > +{
> > + strscpy(cap->driver, MEM2MEM_NAME, sizeof(cap->driver));
> > + strscpy(cap->card, MEM2MEM_NAME, sizeof(cap->card));
> > + snprintf(cap->bus_info, sizeof(cap->bus_info),
> > + "platform:%s", MEM2MEM_NAME);
>
> You can drop this bus_info line, it's filled in for you.
I see there is a warning from v4l2-compliance test if this line is removed.
warn: v4l2-compliance.cpp(676): media bus_info 'platform:vim2m-audio'
differs from V4L2 bus_info 'platform:vim2m-audio.0'
Best regards
Shengjiu Wang
>
> > +
> > + return 0;
> > +}
> > +
> > +static int enum_fmt(struct v4l2_fmtdesc *f)
> > +{
> > + int i, num;
> > +
> > + num = 0;
> > +
> > + for (i = 0; i < NUM_FORMATS; ++i) {
> > + if (num == f->index)
> > + break;
> > + /*
> > + * Correct type but haven't reached our index yet,
> > + * just increment per-type index
> > + */
> > + ++num;
> > + }
> > +
> > + if (i < NUM_FORMATS) {
> > + /* Format found */
> > + f->pixelformat = formats[i];
> > + return 0;
> > + }
> > +
> > + /* Format not found */
> > + return -EINVAL;
> > +}
> > +
> > +static int audm2m_enum_fmt_audio_cap(struct file *file, void *priv,
> > + struct v4l2_fmtdesc *f)
> > +{
> > + return enum_fmt(f);
> > +}
> > +
> > +static int audm2m_enum_fmt_audio_out(struct file *file, void *priv,
> > + struct v4l2_fmtdesc *f)
> > +{
> > + return enum_fmt(f);
> > +}
> > +
> > +static int audm2m_g_fmt(struct audm2m_ctx *ctx, struct v4l2_format *f)
> > +{
> > + struct vb2_queue *vq;
> > + struct audm2m_q_data *q_data;
> > +
> > + vq = v4l2_m2m_get_vq(ctx->fh.m2m_ctx, f->type);
> > + if (!vq)
> > + return -EINVAL;
> > +
> > + q_data = get_q_data(ctx, f->type);
> > + if (!q_data)
> > + return -EINVAL;
> > +
> > + f->fmt.audio.audioformat = q_data->fourcc;
> > + f->fmt.audio.channels = q_data->channels;
> > + f->fmt.audio.buffersize = q_data->buffersize;
> > +
> > + return 0;
> > +}
> > +
> > +static int audm2m_g_fmt_audio_out(struct file *file, void *priv,
> > + struct v4l2_format *f)
> > +{
> > + return audm2m_g_fmt(file2ctx(file), f);
> > +}
> > +
> > +static int audm2m_g_fmt_audio_cap(struct file *file, void *priv,
> > + struct v4l2_format *f)
> > +{
> > + return audm2m_g_fmt(file2ctx(file), f);
> > +}
> > +
> > +static int audm2m_try_fmt(struct v4l2_format *f, snd_pcm_format_t fmt)
> > +{
> > + f->fmt.audio.channels = 1;
> > + f->fmt.audio.buffersize = f->fmt.audio.channels *
> > + snd_pcm_format_physical_width(fmt) *
> > + SAMPLE_NUM;
> > + return 0;
> > +}
> > +
> > +static int audm2m_try_fmt_audio_cap(struct file *file, void *priv,
> > + struct v4l2_format *f)
> > +{
> > + snd_pcm_format_t fmt;
> > +
> > + fmt = find_format(f->fmt.audio.audioformat);
> > + if (!fmt) {
> > + f->fmt.audio.audioformat = formats[0];
> > + fmt = find_format(f->fmt.audio.audioformat);
> > + }
> > +
> > + return audm2m_try_fmt(f, fmt);
> > +}
> > +
> > +static int audm2m_try_fmt_audio_out(struct file *file, void *priv,
> > + struct v4l2_format *f)
> > +{
> > + snd_pcm_format_t fmt;
> > +
> > + fmt = find_format(f->fmt.audio.audioformat);
> > + if (!fmt) {
> > + f->fmt.audio.audioformat = formats[0];
> > + fmt = find_format(f->fmt.audio.audioformat);
> > + }
> > +
> > + return audm2m_try_fmt(f, fmt);
> > +}
> > +
> > +static int audm2m_s_fmt(struct audm2m_ctx *ctx, struct v4l2_format *f)
> > +{
> > + struct audm2m_q_data *q_data;
> > + struct vb2_queue *vq;
> > + snd_pcm_format_t fmt;
> > +
> > + vq = v4l2_m2m_get_vq(ctx->fh.m2m_ctx, f->type);
> > + if (!vq)
> > + return -EINVAL;
> > +
> > + q_data = get_q_data(ctx, f->type);
> > + if (!q_data)
> > + return -EINVAL;
> > +
> > + if (vb2_is_busy(vq)) {
> > + v4l2_err(&ctx->dev->v4l2_dev, "%s queue busy\n", __func__);
> > + return -EBUSY;
> > + }
> > +
> > + q_data->fourcc = f->fmt.audio.audioformat;
> > + q_data->channels = f->fmt.audio.channels;
> > +
> > + fmt = find_format(f->fmt.audio.audioformat);
> > + q_data->buffersize = q_data->channels *
> > + snd_pcm_format_physical_width(fmt) *
> > + SAMPLE_NUM;
> > +
> > + dprintk(ctx->dev, 1,
> > + "Format for type %s: %d/%d, fmt: %c%c%c%c\n",
> > + type_name(f->type), q_data->rate,
> > + q_data->channels,
> > + (q_data->fourcc & 0xff),
> > + (q_data->fourcc >> 8) & 0xff,
> > + (q_data->fourcc >> 16) & 0xff,
> > + (q_data->fourcc >> 24) & 0xff);
> > +
> > + return 0;
> > +}
> > +
> > +static int audm2m_s_fmt_audio_cap(struct file *file, void *priv,
> > + struct v4l2_format *f)
> > +{
> > + int ret;
> > +
> > + ret = audm2m_try_fmt_audio_cap(file, priv, f);
> > + if (ret)
> > + return ret;
> > +
> > + return audm2m_s_fmt(file2ctx(file), f);
> > +}
> > +
> > +static int audm2m_s_fmt_audio_out(struct file *file, void *priv,
> > + struct v4l2_format *f)
> > +{
> > + int ret;
> > +
> > + ret = audm2m_try_fmt_audio_out(file, priv, f);
> > + if (ret)
> > + return ret;
> > +
> > + return audm2m_s_fmt(file2ctx(file), f);
> > +}
> > +
> > +static const struct v4l2_ioctl_ops audm2m_ioctl_ops = {
> > + .vidioc_querycap = audm2m_querycap,
> > +
> > + .vidioc_enum_fmt_audio_cap = audm2m_enum_fmt_audio_cap,
> > + .vidioc_g_fmt_audio_cap = audm2m_g_fmt_audio_cap,
> > + .vidioc_try_fmt_audio_cap = audm2m_try_fmt_audio_cap,
> > + .vidioc_s_fmt_audio_cap = audm2m_s_fmt_audio_cap,
> > +
> > + .vidioc_enum_fmt_audio_out = audm2m_enum_fmt_audio_out,
> > + .vidioc_g_fmt_audio_out = audm2m_g_fmt_audio_out,
> > + .vidioc_try_fmt_audio_out = audm2m_try_fmt_audio_out,
> > + .vidioc_s_fmt_audio_out = audm2m_s_fmt_audio_out,
> > +
> > + .vidioc_reqbufs = v4l2_m2m_ioctl_reqbufs,
> > + .vidioc_querybuf = v4l2_m2m_ioctl_querybuf,
> > + .vidioc_qbuf = v4l2_m2m_ioctl_qbuf,
> > + .vidioc_dqbuf = v4l2_m2m_ioctl_dqbuf,
> > + .vidioc_prepare_buf = v4l2_m2m_ioctl_prepare_buf,
> > + .vidioc_create_bufs = v4l2_m2m_ioctl_create_bufs,
> > + .vidioc_expbuf = v4l2_m2m_ioctl_expbuf,
> > +
> > + .vidioc_streamon = v4l2_m2m_ioctl_streamon,
> > + .vidioc_streamoff = v4l2_m2m_ioctl_streamoff,
> > +
> > + .vidioc_subscribe_event = v4l2_ctrl_subscribe_event,
> > + .vidioc_unsubscribe_event = v4l2_event_unsubscribe,
> > +};
> > +
> > +/*
> > + * Queue operations
> > + */
> > +static int audm2m_queue_setup(struct vb2_queue *vq,
> > + unsigned int *nbuffers,
> > + unsigned int *nplanes,
> > + unsigned int sizes[],
> > + struct device *alloc_devs[])
> > +{
> > + struct audm2m_ctx *ctx = vb2_get_drv_priv(vq);
> > + struct audm2m_q_data *q_data;
> > +
> > + q_data = get_q_data(ctx, vq->type);
> > +
> > + if (*nplanes)
> > + return sizes[0] < q_data->buffersize ? -EINVAL : 0;
> > +
> > + *nplanes = 1;
> > + sizes[0] = q_data->buffersize;
> > +
> > + dprintk(ctx->dev, 1, "%s: get %d buffer(s) of size %d each.\n",
> > + type_name(vq->type), *nplanes, sizes[0]);
> > +
> > + return 0;
> > +}
> > +
> > +static void audm2m_buf_queue(struct vb2_buffer *vb)
> > +{
> > + struct vb2_v4l2_buffer *vbuf = to_vb2_v4l2_buffer(vb);
> > + struct audm2m_ctx *ctx = vb2_get_drv_priv(vb->vb2_queue);
> > +
> > + v4l2_m2m_buf_queue(ctx->fh.m2m_ctx, vbuf);
> > +}
> > +
> > +static int audm2m_start_streaming(struct vb2_queue *q, unsigned int count)
> > +{
> > + struct audm2m_ctx *ctx = vb2_get_drv_priv(q);
> > + struct audm2m_q_data *q_data = get_q_data(ctx, q->type);
> > +
> > + q_data->sequence = 0;
> > + return 0;
> > +}
> > +
> > +static void audm2m_stop_streaming(struct vb2_queue *q)
> > +{
> > + struct audm2m_ctx *ctx = vb2_get_drv_priv(q);
> > + struct vb2_v4l2_buffer *vbuf;
> > +
> > + for (;;) {
> > + if (V4L2_TYPE_IS_OUTPUT(q->type))
> > + vbuf = v4l2_m2m_src_buf_remove(ctx->fh.m2m_ctx);
> > + else
> > + vbuf = v4l2_m2m_dst_buf_remove(ctx->fh.m2m_ctx);
> > + if (!vbuf)
> > + return;
> > + v4l2_m2m_buf_done(vbuf, VB2_BUF_STATE_ERROR);
> > + }
> > +}
> > +
> > +static const struct vb2_ops audm2m_qops = {
> > + .queue_setup = audm2m_queue_setup,
> > + .buf_queue = audm2m_buf_queue,
> > + .start_streaming = audm2m_start_streaming,
> > + .stop_streaming = audm2m_stop_streaming,
> > + .wait_prepare = vb2_ops_wait_prepare,
> > + .wait_finish = vb2_ops_wait_finish,
> > +};
> > +
> > +static int queue_init(void *priv, struct vb2_queue *src_vq,
> > + struct vb2_queue *dst_vq)
> > +{
> > + struct audm2m_ctx *ctx = priv;
> > + int ret;
> > +
> > + src_vq->type = V4L2_BUF_TYPE_AUDIO_OUTPUT;
> > + src_vq->io_modes = VB2_MMAP | VB2_DMABUF;
> > + src_vq->drv_priv = ctx;
> > + src_vq->buf_struct_size = sizeof(struct v4l2_m2m_buffer);
> > + src_vq->ops = &audm2m_qops;
> > + src_vq->mem_ops = &vb2_vmalloc_memops;
> > + src_vq->timestamp_flags = V4L2_BUF_FLAG_TIMESTAMP_COPY;
> > + src_vq->lock = &ctx->vb_mutex;
> > + src_vq->min_buffers_needed = 1;
>
> Drop this, it's not needed.
>
> > +
> > + ret = vb2_queue_init(src_vq);
> > + if (ret)
> > + return ret;
> > +
> > + dst_vq->type = V4L2_BUF_TYPE_AUDIO_CAPTURE;
> > + dst_vq->io_modes = VB2_MMAP | VB2_DMABUF;
> > + dst_vq->drv_priv = ctx;
> > + dst_vq->buf_struct_size = sizeof(struct v4l2_m2m_buffer);
> > + dst_vq->ops = &audm2m_qops;
> > + dst_vq->mem_ops = &vb2_vmalloc_memops;
> > + dst_vq->timestamp_flags = V4L2_BUF_FLAG_TIMESTAMP_COPY;
> > + dst_vq->lock = &ctx->vb_mutex;
> > + dst_vq->min_buffers_needed = 1;
>
> Ditto.
>
> > +
> > + return vb2_queue_init(dst_vq);
> > +}
> > +
> > +static const s64 audm2m_rates[] = {
> > + 8000, 16000,
> > +};
> > +
> > +static int audm2m_op_s_ctrl(struct v4l2_ctrl *ctrl)
> > +{
> > + struct audm2m_ctx *ctx =
> > + container_of(ctrl->handler, struct audm2m_ctx, ctrl_handler);
> > + int ret = 0;
> > +
> > + switch (ctrl->id) {
> > + case V4L2_CID_M2M_AUDIO_SOURCE_RATE:
> > + ctx->q_data[V4L2_M2M_SRC].rate = ctrl->qmenu_int[ctrl->val];
> > + break;
> > + case V4L2_CID_M2M_AUDIO_DEST_RATE:
> > + ctx->q_data[V4L2_M2M_DST].rate = ctrl->qmenu_int[ctrl->val];
> > + break;
> > + default:
> > + ret = -EINVAL;
> > + break;
> > + }
> > +
> > + return ret;
> > +}
> > +
> > +static const struct v4l2_ctrl_ops audm2m_ctrl_ops = {
> > + .s_ctrl = audm2m_op_s_ctrl,
> > +};
> > +
> > +/*
> > + * File operations
> > + */
> > +static int audm2m_open(struct file *file)
> > +{
> > + struct audm2m_dev *dev = video_drvdata(file);
> > + struct audm2m_ctx *ctx = NULL;
> > + snd_pcm_format_t fmt;
> > + int width;
> > + int rc = 0;
> > +
> > + if (mutex_lock_interruptible(&dev->dev_mutex))
> > + return -ERESTARTSYS;
> > + ctx = kzalloc(sizeof(*ctx), GFP_KERNEL);
> > + if (!ctx) {
> > + rc = -ENOMEM;
> > + goto open_unlock;
> > + }
> > +
> > + v4l2_fh_init(&ctx->fh, video_devdata(file));
> > + file->private_data = &ctx->fh;
> > + ctx->dev = dev;
> > +
> > + ctx->q_data[V4L2_M2M_SRC].fourcc = formats[0];
> > + ctx->q_data[V4L2_M2M_SRC].rate = 8000;
> > + ctx->q_data[V4L2_M2M_SRC].channels = 1;
> > +
> > + /* Fix to 4096 samples */
> > + fmt = find_format(formats[0]);
> > + width = snd_pcm_format_physical_width(fmt);
> > + ctx->q_data[V4L2_M2M_SRC].buffersize = SAMPLE_NUM * width;
> > + ctx->q_data[V4L2_M2M_DST] = ctx->q_data[V4L2_M2M_SRC];
> > +
> > + ctx->fh.m2m_ctx = v4l2_m2m_ctx_init(dev->m2m_dev, ctx, &queue_init);
> > +
> > + mutex_init(&ctx->vb_mutex);
> > +
> > + if (IS_ERR(ctx->fh.m2m_ctx)) {
> > + rc = PTR_ERR(ctx->fh.m2m_ctx);
> > +
> > + v4l2_fh_exit(&ctx->fh);
> > + kfree(ctx);
> > + goto open_unlock;
> > + }
> > +
> > + v4l2_fh_add(&ctx->fh);
> > +
> > + dprintk(dev, 1, "Created instance: %p, m2m_ctx: %p\n",
> > + ctx, ctx->fh.m2m_ctx);
> > +
> > + v4l2_ctrl_handler_init(&ctx->ctrl_handler, 2);
> > +
> > + v4l2_ctrl_new_int_menu(&ctx->ctrl_handler, &audm2m_ctrl_ops,
> > + V4L2_CID_M2M_AUDIO_SOURCE_RATE,
> > + ARRAY_SIZE(audm2m_rates) - 1, 0, audm2m_rates);
> > + v4l2_ctrl_new_int_menu(&ctx->ctrl_handler, &audm2m_ctrl_ops,
> > + V4L2_CID_M2M_AUDIO_DEST_RATE,
> > + ARRAY_SIZE(audm2m_rates) - 1, 0, audm2m_rates);
> > +
> > + if (ctx->ctrl_handler.error) {
> > + rc = ctx->ctrl_handler.error;
> > + v4l2_ctrl_handler_free(&ctx->ctrl_handler);
> > + goto err_ctrl_handler;
> > + }
> > +
> > + ctx->fh.ctrl_handler = &ctx->ctrl_handler;
> > +
> > + mutex_unlock(&dev->dev_mutex);
> > +
> > + return 0;
> > +
> > +err_ctrl_handler:
> > + v4l2_m2m_ctx_release(ctx->fh.m2m_ctx);
> > +open_unlock:
> > + mutex_unlock(&dev->dev_mutex);
> > + return rc;
> > +}
> > +
> > +static int audm2m_release(struct file *file)
> > +{
> > + struct audm2m_dev *dev = video_drvdata(file);
> > + struct audm2m_ctx *ctx = file2ctx(file);
> > +
> > + dprintk(dev, 1, "Releasing instance %p\n", ctx);
> > +
> > + v4l2_ctrl_handler_free(&ctx->ctrl_handler);
> > + v4l2_fh_del(&ctx->fh);
> > + v4l2_fh_exit(&ctx->fh);
> > + mutex_lock(&dev->dev_mutex);
> > + v4l2_m2m_ctx_release(ctx->fh.m2m_ctx);
> > + mutex_unlock(&dev->dev_mutex);
> > + kfree(ctx);
> > +
> > + return 0;
> > +}
> > +
> > +static void audm2m_device_release(struct video_device *vdev)
> > +{
> > + struct audm2m_dev *dev = container_of(vdev, struct audm2m_dev, vfd);
> > +
> > + v4l2_device_unregister(&dev->v4l2_dev);
> > + v4l2_m2m_release(dev->m2m_dev);
> > +
> > +#ifdef CONFIG_MEDIA_CONTROLLER
> > + media_device_cleanup(&dev->mdev);
> > +#endif
> > + kfree(dev);
> > +}
> > +
> > +static const struct v4l2_file_operations audm2m_fops = {
> > + .owner = THIS_MODULE,
> > + .open = audm2m_open,
> > + .release = audm2m_release,
> > + .poll = v4l2_m2m_fop_poll,
> > + .unlocked_ioctl = video_ioctl2,
> > + .mmap = v4l2_m2m_fop_mmap,
> > +};
> > +
> > +static const struct video_device audm2m_videodev = {
> > + .name = MEM2MEM_NAME,
> > + .vfl_dir = VFL_DIR_M2M,
> > + .fops = &audm2m_fops,
> > + .ioctl_ops = &audm2m_ioctl_ops,
> > + .minor = -1,
> > + .release = audm2m_device_release,
> > + .device_caps = V4L2_CAP_AUDIO_M2M | V4L2_CAP_STREAMING,
> > +};
> > +
> > +static const struct v4l2_m2m_ops m2m_ops = {
> > + .device_run = device_run,
> > +};
> > +
> > +static const struct media_device_ops audm2m_media_ops = {
> > + .req_validate = vb2_request_validate,
> > + .req_queue = v4l2_m2m_request_queue,
> > +};
> > +
> > +static int audm2m_probe(struct platform_device *pdev)
> > +{
> > + struct audm2m_dev *dev;
> > + struct video_device *vfd;
> > + int ret;
> > +
> > + dev = kzalloc(sizeof(*dev), GFP_KERNEL);
> > + if (!dev)
> > + return -ENOMEM;
> > +
> > + ret = v4l2_device_register(&pdev->dev, &dev->v4l2_dev);
> > + if (ret)
> > + goto error_free;
> > +
> > + mutex_init(&dev->dev_mutex);
> > +
> > + dev->vfd = audm2m_videodev;
> > + vfd = &dev->vfd;
> > + vfd->lock = &dev->dev_mutex;
> > + vfd->v4l2_dev = &dev->v4l2_dev;
> > +
> > + video_set_drvdata(vfd, dev);
> > + platform_set_drvdata(pdev, dev);
> > +
> > + dev->m2m_dev = v4l2_m2m_init(&m2m_ops);
> > + if (IS_ERR(dev->m2m_dev)) {
> > + v4l2_err(&dev->v4l2_dev, "Failed to init mem2mem device\n");
> > + ret = PTR_ERR(dev->m2m_dev);
> > + dev->m2m_dev = NULL;
> > + goto error_dev;
> > + }
> > +
> > +#ifdef CONFIG_MEDIA_CONTROLLER
> > + dev->mdev.dev = &pdev->dev;
> > + strscpy(dev->mdev.model, MEM2MEM_NAME, sizeof(dev->mdev.model));
> > + snprintf(dev->mdev.bus_info, sizeof(dev->mdev.bus_info),
> > + "platform:%s", MEM2MEM_NAME);
> > + media_device_init(&dev->mdev);
> > + dev->mdev.ops = &audm2m_media_ops;
> > + dev->v4l2_dev.mdev = &dev->mdev;
> > +#endif
> > +
> > + ret = video_register_device(vfd, VFL_TYPE_AUDIO, 0);
> > + if (ret) {
> > + v4l2_err(&dev->v4l2_dev, "Failed to register video device\n");
> > + goto error_m2m;
> > + }
> > +
> > +#ifdef CONFIG_MEDIA_CONTROLLER
> > + ret = v4l2_m2m_register_media_controller(dev->m2m_dev, vfd,
> > + MEDIA_ENT_F_PROC_AUDIO_RESAMPLER);
> > + if (ret) {
> > + v4l2_err(&dev->v4l2_dev, "Failed to init mem2mem media controller\n");
> > + goto error_v4l2;
> > + }
> > +
> > + ret = media_device_register(&dev->mdev);
> > + if (ret) {
> > + v4l2_err(&dev->v4l2_dev, "Failed to register mem2mem media device\n");
> > + goto error_m2m_mc;
> > + }
> > +#endif
> > +
> > + v4l2_info(&dev->v4l2_dev,
> > + "Device registered as /dev/v4l-audio%d\n", vfd->num);
> > +
> > + return 0;
> > +
> > +#ifdef CONFIG_MEDIA_CONTROLLER
> > +error_m2m_mc:
> > + v4l2_m2m_unregister_media_controller(dev->m2m_dev);
> > +#endif
> > +error_v4l2:
> > + video_unregister_device(&dev->vfd);
> > + /* audm2m_device_release called by video_unregister_device to release various objects */
> > + return ret;
> > +error_m2m:
> > + v4l2_m2m_release(dev->m2m_dev);
> > +error_dev:
> > + v4l2_device_unregister(&dev->v4l2_dev);
> > +error_free:
> > + kfree(dev);
> > +
> > + return ret;
> > +}
> > +
> > +static void audm2m_remove(struct platform_device *pdev)
> > +{
> > + struct audm2m_dev *dev = platform_get_drvdata(pdev);
> > +
> > + v4l2_info(&dev->v4l2_dev, "Removing " MEM2MEM_NAME);
> > +
> > +#ifdef CONFIG_MEDIA_CONTROLLER
> > + media_device_unregister(&dev->mdev);
> > + v4l2_m2m_unregister_media_controller(dev->m2m_dev);
> > +#endif
> > + video_unregister_device(&dev->vfd);
> > +}
> > +
> > +static struct platform_driver audm2m_pdrv = {
> > + .probe = audm2m_probe,
> > + .remove_new = audm2m_remove,
> > + .driver = {
> > + .name = MEM2MEM_NAME,
> > + },
> > +};
> > +
> > +static void __exit audm2m_exit(void)
> > +{
> > + platform_driver_unregister(&audm2m_pdrv);
> > + platform_device_unregister(&audm2m_pdev);
> > +}
> > +
> > +static int __init audm2m_init(void)
> > +{
> > + int ret;
> > +
> > + ret = platform_device_register(&audm2m_pdev);
> > + if (ret)
> > + return ret;
> > +
> > + ret = platform_driver_register(&audm2m_pdrv);
> > + if (ret)
> > + platform_device_unregister(&audm2m_pdev);
> > +
> > + return ret;
> > +}
> > +
> > +module_init(audm2m_init);
> > +module_exit(audm2m_exit);
>
> Regards,
>
> Hans