Re: [RESEND PATCH v2 06/15] ASoC: qcom: qdsp6: Add support to Q6ASM

[Srinivas Kandagatla]

On 02/01/18 04:43, Bjorn Andersson wrote:
> On Thu 14 Dec 09:33 PST 2017, srinivas.kandagatla@xxxxxxxxxx wrote:
>
> > From: Srinivas Kandagatla <srinivas.kandagatla@xxxxxxxxxx>
> >
> > This patch adds basic support to Q6 ASM (Audio Stream Manager) module on
> > Q6DSP. ASM supports up to 8 concurrent streams. each stream can be setup
> > as playback/capture.
>
> "...streams, each one setup as either playback or capture".
>
> or "each" need to be capitalized.
>
> > ASM provides top control functions like
> > Pause/flush/resume for playback and record. ASM can Create/destroy encoder,
>
> lower case p and c
>
> > decoder and also provides POPP dynamic services.
>
> Please describe what POPP is.
Yep, will fix the commit log as suggested.

> [..]
> > +struct audio_client {
> > +	int session;
> > +	app_cb cb;
> > +	int cmd_state;
> > +	void *priv;
> > +	uint32_t io_mode;
> > +	uint64_t time_stamp;
>
> Unused.
will remove this in next version.

> > +	struct apr_device *adev;
> > +	struct mutex cmd_lock;
> > +	wait_queue_head_t cmd_wait;
> > +	int perf_mode;
> > +	int stream_id;
> > +	struct device *dev;
> > +};
> > +
> > +struct q6asm {
> > +	struct apr_device *adev;
> > +	int mem_state;
> > +	struct device *dev;
> > +	wait_queue_head_t mem_wait;
> > +	struct mutex	session_lock;
> > +	struct platform_device *pcmdev;
> > +	struct audio_client *session[MAX_SESSIONS + 1];
> > +};
> > +
> > +static int q6asm_session_alloc(struct audio_client *ac, struct q6asm *a)
>
> Move the allocation of ac into this function, and return the newly
> allocated ac - that way the name of this function makes more sense.
will try that, it should cleanup some code.

> > +{
> > +	int n = -EINVAL;
>
> You're returning MAX_SESSIONS if no free sessions are found, but are
> checking for <= 0 in the caller.

I will make sure that its checked correctly and i will also update the 
kernel doc to reflect this.

> > +
> > +	mutex_lock(&a->session_lock);
> > +	for (n = 1; n <= MAX_SESSIONS; n++) {
>
> Is there an external reason for session 0 not being considered?
Yes, session 0 is reserved.

> > +		if (!a->session[n]) {
> > +			a->session[n] = ac;
> > +			break;
> > +		}
> > +	}
>
> If you make session an idr this function would become idr_alloc(1,
> MAX_SESSIONS + 1).
will try idr and see how it looks.
> > +	mutex_unlock(&a->session_lock);
> > +
> > +	return n;
> > +}
> > +
> > +static bool q6asm_is_valid_audio_client(struct audio_client *ac)
> > +{
> > +	struct q6asm *a = dev_get_drvdata(ac->dev->parent);
> > +	int n;
> > +
> > +	for (n = 1; n <= MAX_SESSIONS; n++) {
> > +		if (a->session[n] == ac)
> > +			return 1;
>
> "true"
thanks, will fix these.
> > +	}
> > +
> > +	return 0;
>
> "false"
>
> > +}
> > +
> > +static void q6asm_session_free(struct audio_client *ac)
> > +{
> > +	struct q6asm *a = dev_get_drvdata(ac->dev->parent);
> > +
> > +	if (!a)
> > +		return;
> > +
> > +	mutex_lock(&a->session_lock);
> > +	a->session[ac->session] = 0;
> > +	ac->session = 0;
> > +	ac->perf_mode = LEGACY_PCM_MODE;
>
> No need to update ac->*, as you kfree ac as soon as you return from
> here.
yep.

> > +	mutex_unlock(&a->session_lock);
> > +}
> > +
> > +/**
> > + * q6asm_audio_client_free() - Freee allocated audio client
> > + *
> > + * @ac: audio client to free
> > + */
> > +void q6asm_audio_client_free(struct audio_client *ac)
> > +{
> > +	q6asm_session_free(ac);
>
> Inline q6asm_session_free() here.
makes sense here.

> > +	kfree(ac);
> > +}
> > +EXPORT_SYMBOL_GPL(q6asm_audio_client_free);
> > +
> > +static struct audio_client *q6asm_get_audio_client(struct q6asm *a,
> > +						   int session_id)
> > +{
> > +	if ((session_id <= 0) || (session_id > MAX_SESSIONS)) {
> > +		dev_err(a->dev, "invalid session: %d\n", session_id);
> > +		goto err;
>
> Just return NULL here instead.
yep.

> > +	}
> > +
> > +	if (!a->session[session_id]) {
> > +		dev_err(a->dev, "session not active: %d\n", session_id);
> > +		goto err;
>
> Dito
>
> > +	}
>
> But this is another place where an idr would be preferable, as both
> these cases would be covered with a call to idr_find()
>
> > +	return a->session[session_id];
> > +err:
> > +	return NULL;
> > +}
> > +
> > +static int q6asm_srvc_callback(struct apr_device *adev, struct apr_client_data *data)
> > +{
> > +	struct q6asm *q6asm = dev_get_drvdata(&adev->dev);
> > +	struct audio_client *ac = NULL;
> > +	uint32_t sid = 0;
>
> This is 4 bits, so just use int.
makes sense.

> > +	uint32_t *payload;
>
> payload is unused.

will remove this in next version.

> > +
> > +	if (!data) {
> > +		dev_err(&adev->dev, "%s: Invalid CB\n", __func__);
> > +		return 0;
> > +	}
>
> Again, define the apr to never invoke the callback with data = NULL
yep.

> > +
> > +	payload = data->payload;
> > +	sid = (data->token >> 8) & 0x0F;
> > +	ac = q6asm_get_audio_client(q6asm, sid);
> > +	if (!ac) {
> > +		dev_err(&adev->dev, "Audio Client not active\n");
> > +		return 0;
> > +	}
> > +
> > +	if (ac->cb)
> > +		ac->cb(data->opcode, data->token, data->payload, ac->priv);
> > +	return 0;
> > +}
> > +

[...]


> > +/**
> > + * q6asm_audio_client_alloc() - Allocate a new audio client
> > + *
> > + * @dev: Pointer to asm child device.
> > + * @cb: event callback.
> > + * @priv: private data associated with this client.
> > + *
> > + * Return: Will be an error pointer on error or a valid audio client
> > + * on success.
> > + */
> > +struct audio_client *q6asm_audio_client_alloc(struct device *dev,
> > +					      app_cb cb, void *priv)
> > +{
> > +	struct q6asm *a = dev_get_drvdata(dev->parent);
> > +	struct audio_client *ac;
> > +	int n;
> > +
> > +	ac = kzalloc(sizeof(struct audio_client), GFP_KERNEL);
>
> sizeof(*ac)

Yep.

> > +	if (!ac)
> > +		return NULL;
> > +
> > +	n = q6asm_session_alloc(ac, a);
>
> As stated above, moving the kzalloc into q6asm_session_alloc() would
> clean the code up here, as you only need to deal with one possible
> error case here.

Will give it a go and see.

> > +	if (n <= 0) {
> > +		dev_err(dev, "ASM Session alloc fail n=%d\n", n);
> > +		kfree(ac);
> > +		return NULL;
>
> Per the kerneldoc I expect an ERR_PTR(n) here.
yep.

> > +	}
> > +
> > +	ac->session = n;
> > +	ac->cb = cb;
> > +	ac->dev = dev;
> > +	ac->priv = priv;
> > +	ac->io_mode = SYNC_IO_MODE;
> > +	ac->perf_mode = LEGACY_PCM_MODE;
> > +	/* DSP expects stream id from 1 */
> > +	ac->stream_id = 1;
> > +	ac->adev = a->adev;
> > +
> > +	init_waitqueue_head(&ac->cmd_wait);
> > +	mutex_init(&ac->cmd_lock);
> > +	ac->cmd_state = 0;
> > +
> > +	return ac;
> > +}
> > +EXPORT_SYMBOL_GPL(q6asm_audio_client_alloc);
> > +
> > +
>
> Extra newline.
yep, will fix it.

[...]
> > +
> > +static struct apr_driver qcom_q6asm_driver = {
> > +	.probe = q6asm_probe,
> > +	.remove = q6asm_remove,
> > +	.callback = q6asm_srvc_callback,
> > +	.id_table = q6asm_id,
> > +	.driver = {
> > +		   .name = "qcom-q6asm",
> > +		   },
>
> Indentation

yep.

> > +};
> > +
> > +module_apr_driver(qcom_q6asm_driver);
> > +MODULE_DESCRIPTION("Q6 Audio Stream Manager driver");
> > +MODULE_LICENSE("GPL v2");
> > diff --git a/sound/soc/qcom/qdsp6/q6asm.h b/sound/soc/qcom/qdsp6/q6asm.h
> > new file mode 100644
> > index 000000000000..7a8a9039fd89
> > --- /dev/null
> > +++ b/sound/soc/qcom/qdsp6/q6asm.h
> > @@ -0,0 +1,14 @@
> > +/* SPDX-License-Identifier: GPL-2.0 */
> > +#ifndef __Q6_ASM_H__
> > +#define __Q6_ASM_H__
> > +
> > +#define MAX_SESSIONS	16
> > +
> > +typedef void (*app_cb) (uint32_t opcode, uint32_t token,
> > +			uint32_t *payload, void *priv);
>
> This name of a type is too generic.
>
> And make payload void *, unless the payload really really is an
> unstructured uint32_t array.
will do that as suggested.
> Regards,
> Bjorn