[alsa-devel] [PATCH 07/12] ASoC: SOF: Implement Probe IPC API

[Pierre-Louis Bossart]

> +/**
> + * sof_ipc_probe_dma_add - attach to specified dmas
> + * @sdev:	SOF sound device
> + * @dma:	List of streams (dmas) to attach to
> + * @num_dma:	Number of elements in @dma
> + *
> + * Contrary to extraction, injection streams are never assigned
> + * on init. Before attempting any data injection, host is responsible
> + * for specifying streams which will be later used to transfer data
> + * to connected probe points.
> + */
> +int sof_ipc_probe_dma_add(struct snd_sof_dev *sdev,
> +		struct sof_probe_dma *dma, size_t num_dma)
> +{
> +	struct sof_ipc_probe_dma_add_params *msg;
> +	struct sof_ipc_reply reply;
> +	size_t bytes = sizeof(*dma) * num_dma;
> +	int ret;
> +
> +	msg = kmalloc(sizeof(*msg) + bytes, GFP_KERNEL);
> +	if (!msg)
> +		return -ENOMEM;
> +	msg->hdr.size = sizeof(*msg);
> +	msg->num_elems = num_dma;
> +	msg->hdr.cmd = SOF_IPC_GLB_PROBE | SOF_IPC_PROBE_DMA_ADD;
> +	memcpy(&msg->dma[0], dma, bytes);
> +
> +	ret = sof_ipc_tx_message(sdev->ipc, msg->hdr.cmd, msg,
> +			msg->hdr.size + bytes, &reply, sizeof(reply));
> +	kfree(msg);
> +	return ret;
> +}
> +EXPORT_SYMBOL(sof_ipc_probe_dma_add);
> +
> +/**
> + * sof_ipc_probe_dma_remove - detach from specified dmas
> + * @sdev:		SOF sound device
> + * @stream_tag:	List of stream tags to detach from
> + * @num_stream_tag:	Number of elements in @stream_tag
> + *
> + * Host sends DMA_REMOVE request to free previously attached stream
> + * from being occupied for injection. Each detach operation should
> + * match equivalent DMA_ADD. Detach only when all probes tied to
> + * given stream have been disconnected.
> + */
> +int sof_ipc_probe_dma_remove(struct snd_sof_dev *sdev,
> +		unsigned int *stream_tag, size_t num_stream_tag)
> +{
> +	struct sof_ipc_probe_dma_remove_params *msg;
> +	struct sof_ipc_reply reply;
> +	size_t bytes = sizeof(*stream_tag) * num_stream_tag;
> +	int ret;
> +
> +	msg = kmalloc(sizeof(*msg) + bytes, GFP_KERNEL);
> +	if (!msg)
> +		return -ENOMEM;
> +	msg->hdr.size = sizeof(*msg);
> +	msg->num_elems = num_stream_tag;
> +	msg->hdr.cmd = SOF_IPC_GLB_PROBE | SOF_IPC_PROBE_DMA_REMOVE;
> +	memcpy(&msg->stream_tag[0], stream_tag, bytes);
> +
> +	ret = sof_ipc_tx_message(sdev->ipc, msg->hdr.cmd, msg,
> +			msg->hdr.size + bytes, &reply, sizeof(reply));
> +	kfree(msg);
> +	return ret;
> +}
> +EXPORT_SYMBOL(sof_ipc_probe_dma_remove);

a lot of the code is identical with only minor difference in num_elems 
and the flags, could we use helper functions here?

This would help btw when we transition to the multi-client support, we'd 
only need to update the IPC stuff in few locations.


> diff --git a/sound/soc/sof/probe.h b/sound/soc/sof/probe.h
> new file mode 100644
> index 000000000000..a5cc24405e7e
> --- /dev/null
> +++ b/sound/soc/sof/probe.h
> @@ -0,0 +1,85 @@
> +/* SPDX-License-Identifier: (GPL-2.0 OR BSD-3-Clause) */
> +/*
> + * This file is provided under a dual BSD/GPLv2 license.  When using or
> + * redistributing this file, you may do so under either license.
> + *
> + * Copyright(c) 2019 Intel Corporation. All rights reserved.

2019-2020. Happy New Year.

I'd prefer it if we have the new header file in a separate patch added 
first, I find it odd to review an implementation with the header added last.