by Shengjiu Wang

[permalink] [raw]

Subject: Re: [PATCH v11 15/15] media: vim2m-audio: add virtual driver for audio memory to memory

On Thu, Jan 18, 2024 at 3:56 PM Hans Verkuil <[email protected]> wrote:
>
> On 18/01/2024 07:13, Shengjiu Wang wrote:
> > On Wed, Jan 17, 2024 at 6:32 PM Hans Verkuil <[email protected]> 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 <[email protected]>
> >>> ---
> >>> 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'
>
> You should also drop the line filling in the bus_info in the media device:
>
> <snip>
>
>
> >>> +static int audm2m_probe(struct platform_device *pdev)
> >>> +{
>
> <snip>
>
> >>> +#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);
>
> Drop this line.
>
> >>> + media_device_init(&dev->mdev);
>
> This function will fill it in automatically as well, and with the same
> name as querycap.
>

Got it. thanks!

Best regards
Shengjiu Wang

> Regards,
>
> Hans
>
> >>> + 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
>