Hi Hans,
I've just pushed v4 with subdev nodes registry removal as per your
suggestion.
On 7/25/19 5:09 PM, Hans Verkuil wrote:
> On 7/25/19 4:56 PM, Benjamin Gaignard wrote:
>> Le jeu. 25 juil. 2019 à 13:40, Hans Verkuil <hverkuil@xxxxxxxxx> a écrit :
>>>
>>> On 7/2/19 5:52 PM, Hugues Fruchet wrote:
>>>> Add support of several sub-devices within pipeline instead
>>>> of a single one.
>>>> This allows to support a CSI-2 camera sensor connected
>>>> through a CSI-2 to parallel bridge.
>>>>
>>>> Signed-off-by: Hugues Fruchet <hugues.fruchet@xxxxxx>
>>>> ---
>>>> drivers/media/platform/stm32/stm32-dcmi.c | 204 +++++++++++++++++++++++++++---
>>>> 1 file changed, 186 insertions(+), 18 deletions(-)
>>>>
>>>> diff --git a/drivers/media/platform/stm32/stm32-dcmi.c b/drivers/media/platform/stm32/stm32-dcmi.c
>>>> index 6f37617..6921e6b 100644
>>>> --- a/drivers/media/platform/stm32/stm32-dcmi.c
>>>> +++ b/drivers/media/platform/stm32/stm32-dcmi.c
>>>> @@ -172,6 +172,7 @@ struct stm32_dcmi {
>>>>
>>>> struct media_device mdev;
>>>> struct media_pad vid_cap_pad;
>>>> + struct media_pipeline pipeline;
>>>> };
>>>>
>>>> static inline struct stm32_dcmi *notifier_to_dcmi(struct v4l2_async_notifier *n)
>>>> @@ -583,6 +584,131 @@ static void dcmi_buf_queue(struct vb2_buffer *vb)
>>>> spin_unlock_irq(&dcmi->irqlock);
>>>> }
>>>>
>>>> +static struct media_entity *dcmi_find_source(struct stm32_dcmi *dcmi)
>>>> +{
>>>> + struct media_entity *entity = &dcmi->vdev->entity;
>>>> + struct media_pad *pad;
>>>> +
>>>> + /* Walk searching for entity having no sink */
>>>> + while (1) {
>>>> + pad = &entity->pads[0];
>>>> + if (!(pad->flags & MEDIA_PAD_FL_SINK))
>>>> + break;
>>>> +
>>>> + pad = media_entity_remote_pad(pad);
>>>> + if (!pad || !is_media_entity_v4l2_subdev(pad->entity))
>>>> + break;
>>>> +
>>>> + entity = pad->entity;
>>>> + }
>>>> +
>>>> + return entity;
>>>> +}
>>>> +
>>>> +static int dcmi_pipeline_s_fmt(struct stm32_dcmi *dcmi,
>>>> + struct v4l2_subdev_pad_config *pad_cfg,
>>>> + struct v4l2_subdev_format *format)
>>>> +{
>>>> + struct media_entity *entity = &dcmi->entity.source->entity;
>>>> + struct v4l2_subdev *subdev;
>>>> + struct media_pad *sink_pad = NULL;
>>>> + struct media_pad *src_pad = NULL;
>>>> + struct media_pad *pad = NULL;
>>>> + struct v4l2_subdev_format fmt = *format;
>>>> + bool found = false;
>>>> + int ret;
>>>> +
>>>> + /*
>>>> + * Starting from sensor subdevice, walk within
>>>> + * pipeline and set format on each subdevice
>>>> + */
>>>> + while (1) {
>>>> + unsigned int i;
>>>> +
>>>> + /* Search if current entity has a source pad */
>>>> + for (i = 0; i < entity->num_pads; i++) {
>>>> + pad = &entity->pads[i];
>>>> + if (pad->flags & MEDIA_PAD_FL_SOURCE) {
>>>> + src_pad = pad;
>>>> + found = true;
>>>> + break;
>>>> + }
>>>> + }
>>>> + if (!found)
>>>> + break;
>>>> +
>>>> + subdev = media_entity_to_v4l2_subdev(entity);
>>>> +
>>>> + /* Propagate format on sink pad if any, otherwise source pad */
>>>> + if (sink_pad)
>>>> + pad = sink_pad;
>>>> +
>>>> + dev_dbg(dcmi->dev, "%s[%d] pad format set to 0x%x %ux%u\n",
>>>> + subdev->name, pad->index, format->format.code,
>>>> + format->format.width, format->format.height);
>>>> +
>>>> + fmt.pad = pad->index;
>>>> + ret = v4l2_subdev_call(subdev, pad, set_fmt, pad_cfg, &fmt);
>>>> + if (ret < 0)
>>>> + return ret;
>>>> +
>>>> + /* Walk to next entity */
>>>> + sink_pad = media_entity_remote_pad(src_pad);
>>>> + if (!sink_pad || !is_media_entity_v4l2_subdev(sink_pad->entity))
>>>> + break;
>>>> +
>>>> + entity = sink_pad->entity;
>>>> + }
>>>> + *format = fmt;
>>>> +
>>>> + return 0;
>>>> +}
>>>> +
>>>> +static int dcmi_pipeline_s_stream(struct stm32_dcmi *dcmi, int state)
>>>> +{
>>>> + struct media_entity *entity = &dcmi->vdev->entity;
>>>> + struct v4l2_subdev *subdev;
>>>> + struct media_pad *pad;
>>>> + int ret;
>>>> +
>>>> + /* Start/stop all entities within pipeline */
>>>> + while (1) {
>>>> + pad = &entity->pads[0];
>>>> + if (!(pad->flags & MEDIA_PAD_FL_SINK))
>>>> + break;
>>>> +
>>>> + pad = media_entity_remote_pad(pad);
>>>> + if (!pad || !is_media_entity_v4l2_subdev(pad->entity))
>>>> + break;
>>>> +
>>>> + entity = pad->entity;
>>>> + subdev = media_entity_to_v4l2_subdev(entity);
>>>> +
>>>> + ret = v4l2_subdev_call(subdev, video, s_stream, state);
>>>> + if (ret < 0 && ret != -ENOIOCTLCMD) {
>>>> + dev_err(dcmi->dev, "%s: %s failed to %s streaming (%d)\n",
>>>> + __func__, subdev->name,
>>>> + state ? "start" : "stop", ret);
>>>> + return ret;
>>>> + }
>>>> +
>>>> + dev_dbg(dcmi->dev, "%s is %s\n",
>>>> + subdev->name, state ? "started" : "stopped");
>>>> + }
>>>> +
>>>> + return 0;
>>>> +}
>>>> +
>>>> +static int dcmi_pipeline_start(struct stm32_dcmi *dcmi)
>>>> +{
>>>> + return dcmi_pipeline_s_stream(dcmi, 1);
>>>> +}
>>>> +
>>>> +static void dcmi_pipeline_stop(struct stm32_dcmi *dcmi)
>>>> +{
>>>> + dcmi_pipeline_s_stream(dcmi, 0);
>>>> +}
>>>> +
>>>> static int dcmi_start_streaming(struct vb2_queue *vq, unsigned int count)
>>>> {
>>>> struct stm32_dcmi *dcmi = vb2_get_drv_priv(vq);
>>>> @@ -597,14 +723,17 @@ static int dcmi_start_streaming(struct vb2_queue *vq, unsigned int count)
>>>> goto err_release_buffers;
>>>> }
>>>>
>>>> - /* Enable stream on the sub device */
>>>> - ret = v4l2_subdev_call(dcmi->entity.source, video, s_stream, 1);
>>>> - if (ret && ret != -ENOIOCTLCMD) {
>>>> - dev_err(dcmi->dev, "%s: Failed to start streaming, subdev streamon error",
>>>> - __func__);
>>>> + ret = media_pipeline_start(&dcmi->vdev->entity, &dcmi->pipeline);
>>>> + if (ret < 0) {
>>>> + dev_err(dcmi->dev, "%s: Failed to start streaming, media pipeline start error (%d)\n",
>>>> + __func__, ret);
>>>> goto err_pm_put;
>>>> }
>>>>
>>>> + ret = dcmi_pipeline_start(dcmi);
>>>> + if (ret)
>>>> + goto err_media_pipeline_stop;
>>>> +
>>>> spin_lock_irq(&dcmi->irqlock);
>>>>
>>>> /* Set bus width */
>>>> @@ -676,7 +805,7 @@ static int dcmi_start_streaming(struct vb2_queue *vq, unsigned int count)
>>>> if (ret) {
>>>> dev_err(dcmi->dev, "%s: Start streaming failed, cannot start capture\n",
>>>> __func__);
>>>> - goto err_subdev_streamoff;
>>>> + goto err_pipeline_stop;
>>>> }
>>>>
>>>> /* Enable interruptions */
>>>> @@ -687,8 +816,11 @@ static int dcmi_start_streaming(struct vb2_queue *vq, unsigned int count)
>>>>
>>>> return 0;
>>>>
>>>> -err_subdev_streamoff:
>>>> - v4l2_subdev_call(dcmi->entity.source, video, s_stream, 0);
>>>> +err_pipeline_stop:
>>>> + dcmi_pipeline_stop(dcmi);
>>>> +
>>>> +err_media_pipeline_stop:
>>>> + media_pipeline_stop(&dcmi->vdev->entity);
>>>>
>>>> err_pm_put:
>>>> pm_runtime_put(dcmi->dev);
>>>> @@ -713,13 +845,10 @@ static void dcmi_stop_streaming(struct vb2_queue *vq)
>>>> {
>>>> struct stm32_dcmi *dcmi = vb2_get_drv_priv(vq);
>>>> struct dcmi_buf *buf, *node;
>>>> - int ret;
>>>>
>>>> - /* Disable stream on the sub device */
>>>> - ret = v4l2_subdev_call(dcmi->entity.source, video, s_stream, 0);
>>>> - if (ret && ret != -ENOIOCTLCMD)
>>>> - dev_err(dcmi->dev, "%s: Failed to stop streaming, subdev streamoff error (%d)\n",
>>>> - __func__, ret);
>>>> + dcmi_pipeline_stop(dcmi);
>>>> +
>>>> + media_pipeline_stop(&dcmi->vdev->entity);
>>>>
>>>> spin_lock_irq(&dcmi->irqlock);
>>>>
>>>> @@ -937,8 +1066,7 @@ static int dcmi_set_fmt(struct stm32_dcmi *dcmi, struct v4l2_format *f)
>>>> mf->width = sd_framesize.width;
>>>> mf->height = sd_framesize.height;
>>>>
>>>> - ret = v4l2_subdev_call(dcmi->entity.source, pad,
>>>> - set_fmt, NULL, &format);
>>>> + ret = dcmi_pipeline_s_fmt(dcmi, NULL, &format);
>>>> if (ret < 0)
>>>> return ret;
>>>>
>>>> @@ -1529,7 +1657,20 @@ static int dcmi_graph_notify_complete(struct v4l2_async_notifier *notifier)
>>>> struct stm32_dcmi *dcmi = notifier_to_dcmi(notifier);
>>>> int ret;
>>>>
>>>> + /*
>>>> + * Now that the graph is complete,
>>>> + * we search for the source subdevice
>>>> + * in order to expose it through V4L2 interface
>>>> + */
>>>> + dcmi->entity.source =
>>>> + media_entity_to_v4l2_subdev(dcmi_find_source(dcmi));
>>>> + if (!dcmi->entity.source) {
>>>> + dev_err(dcmi->dev, "Source subdevice not found\n");
>>>> + return -ENODEV;
>>>> + }
>>>> +
>>>> dcmi->vdev->ctrl_handler = dcmi->entity.source->ctrl_handler;
>>>> +
>>>> ret = dcmi_formats_init(dcmi);
>>>> if (ret) {
>>>> dev_err(dcmi->dev, "No supported mediabus format found\n");
>>>> @@ -1574,12 +1715,30 @@ static int dcmi_graph_notify_bound(struct v4l2_async_notifier *notifier,
>>>> struct v4l2_async_subdev *asd)
>>>> {
>>>> struct stm32_dcmi *dcmi = notifier_to_dcmi(notifier);
>>>> + unsigned int ret;
>>>> + int src_pad;
>>>>
>>>> dev_dbg(dcmi->dev, "Subdev %s bound\n", subdev->name);
>>>>
>>>> - dcmi->entity.source = subdev;
>>>> + /*
>>>> + * Link this sub-device to DCMI, it could be
>>>> + * a parallel camera sensor or a bridge
>>>> + */
>>>> + src_pad = media_entity_get_fwnode_pad(&subdev->entity,
>>>> + subdev->fwnode,
>>>> + MEDIA_PAD_FL_SOURCE);
>>>> +
>>>> + ret = media_create_pad_link(&subdev->entity, src_pad,
>>>> + &dcmi->vdev->entity, 0,
>>>> + MEDIA_LNK_FL_IMMUTABLE |
>>>> + MEDIA_LNK_FL_ENABLED);
>>>> + if (ret)
>>>> + dev_err(dcmi->dev, "Failed to create media pad link with subdev %s\n",
>>>> + subdev->name);
>>>> + else
>>>> + dev_dbg(dcmi->dev, "DCMI is now linked to %s\n", subdev->name);
>>>>
>>>> - return 0;
>>>> + return ret;
>>>> }
>>>>
>>>> static const struct v4l2_async_notifier_operations dcmi_graph_notify_ops = {
>>>> @@ -1639,6 +1798,15 @@ static int dcmi_graph_init(struct stm32_dcmi *dcmi)
>>>> return ret;
>>>> }
>>>>
>>>> + /* Register all the subdev nodes */
>>>> + ret = v4l2_device_register_subdev_nodes(&dcmi->v4l2_dev);
>>>
>>> This shouldn't be needed. Only MC-centric drivers (i.e. where the pipeline
>>> has to be configured by userspace) need to do this.
>>
>> Hi Hans,
>> I think this point has been discussed in this thread
>> https://www.spinics.net/lists/linux-media/msg153417.html
>>
>> In short : since the hardware only offer one possible path we don't expose
>> the configuration to userland and let DCMI driver configure the
>> subdevice (like bridge).
>
> Yes, and I agree completely. But why then do you register v4l-subdevX devices?
> That's not needed for this driver.
>
> Regards,
>
> Hans
>
>>
>> Benjamin
>>
>>>
>>> Otherwise this patch looks good.
>>>
>>> Regards,
>>>
>>> Hans
>>>
>>>> + if (ret) {
>>>> + dev_err(dcmi->dev, "Failed to register subdev nodes\n");
>>>> + v4l2_async_notifier_unregister(&dcmi->notifier);
>>>> + of_node_put(dcmi->entity.remote_node);
>>>> + return ret;
>>>> + }
>>>> +
>>>> return 0;
>>>> }
>>>>
>>>>
>>>
>
Best regards,
Hugues.
