[PATCH 1/2 v4] ALSA: Add snd_ctl_replace() to dynamically replace a control

[PATCH 1/2 v4] ALSA: Add snd_ctl_replace() to dynamically replace a control

[Dimitris Papastamos]

Add a function to dynamically replace a given control.  If the
control does not already exist, a third parameter is used to determine
whether to actually add that control.  This is useful in cases where
downloadable firmware at runtime can add or replace existing controls.
A separate patch needs to be made to allow ALSA Mixer to render the
replaced controls on the fly.

Signed-off-by: Dimitris Papastamos <dp@opensource.wolfsonmicro.com>
---
 include/sound/control.h |    1 +
 sound/core/control.c    |   65 +++++++++++++++++++++++++++++++++++++++++++++++
 2 files changed, 66 insertions(+), 0 deletions(-)

diff --git a/include/sound/control.h b/include/sound/control.h
index e67db28..1c8b3ee 100644
--- a/include/sound/control.h
+++ b/include/sound/control.h
@@ -113,6 +113,7 @@ struct snd_kcontrol *snd_ctl_new1(const struct snd_kcontrol_new * kcontrolnew, v
 void snd_ctl_free_one(struct snd_kcontrol * kcontrol);
 int snd_ctl_add(struct snd_card * card, struct snd_kcontrol * kcontrol);
 int snd_ctl_remove(struct snd_card * card, struct snd_kcontrol * kcontrol);
+int snd_ctl_replace(struct snd_card * card, struct snd_kcontrol * kcontrol, bool add_on_replace);
 int snd_ctl_remove_id(struct snd_card * card, struct snd_ctl_elem_id *id);
 int snd_ctl_rename_id(struct snd_card * card, struct snd_ctl_elem_id *src_id, struct snd_ctl_elem_id *dst_id);
 int snd_ctl_activate_id(struct snd_card *card, struct snd_ctl_elem_id *id,
diff --git a/sound/core/control.c b/sound/core/control.c
index db51e4e..a8cae8a 100644
--- a/sound/core/control.c
+++ b/sound/core/control.c
@@ -368,6 +368,71 @@ int snd_ctl_add(struct snd_card *card, struct snd_kcontrol *kcontrol)
 EXPORT_SYMBOL(snd_ctl_add);
 
 /**
+ * snd_ctl_replace - replace the control instance of the card
+ * @card: the card instance
+ * @kcontrol: the control instance to replace
+ * @add_on_replace: add the control if not already added
+ *
+ * Replaces the given control.  If the given control does not exist
+ * and the add_on_replace flag is set, the control is added.  If the
+ * control exists, it is destroyed first.
+ *
+ * Returns zero if successful, or a negative error code on failure.
+ *
+ * It frees automatically the control which cannot be added or replaced.
+ */
+int snd_ctl_replace(struct snd_card *card, struct snd_kcontrol *kcontrol,
+		    bool add_on_replace)
+{
+	struct snd_ctl_elem_id id;
+	unsigned int idx;
+	struct snd_kcontrol *old;
+	int ret;
+
+	if (!kcontrol)
+		return -EINVAL;
+	if (snd_BUG_ON(!card || !kcontrol->info)) {
+		ret = -EINVAL;
+		goto error;
+	}
+	id = kcontrol->id;
+	down_write(&card->controls_rwsem);
+	old = snd_ctl_find_id(card, &id);
+	if (!old) {
+		if (add_on_replace)
+			goto add;
+		up_write(&card->controls_rwsem);
+		ret = -EINVAL;
+		goto error;
+	}
+	ret = snd_ctl_remove(card, old);
+	if (ret < 0) {
+		up_write(&card->controls_rwsem);
+		goto error;
+	}
+add:
+	if (snd_ctl_find_hole(card, kcontrol->count) < 0) {
+		up_write(&card->controls_rwsem);
+		ret = -ENOMEM;
+		goto error;
+	}
+	list_add_tail(&kcontrol->list, &card->controls);
+	card->controls_count += kcontrol->count;
+	kcontrol->id.numid = card->last_numid + 1;
+	card->last_numid += kcontrol->count;
+	up_write(&card->controls_rwsem);
+	for (idx = 0; idx < kcontrol->count; idx++, id.index++, id.numid++)
+		snd_ctl_notify(card, SNDRV_CTL_EVENT_MASK_ADD, &id);
+	return 0;
+
+error:
+	snd_ctl_free_one(kcontrol);
+	return ret;
+}
+
+EXPORT_SYMBOL(snd_ctl_replace);
+
+/**
  * snd_ctl_remove - remove the control from the card and release it
  * @card: the card instance
  * @kcontrol: the control instance to remove
-- 
1.7.4.1

[PATCH 2/2 v4] ASoC: soc-core: Add helper function to handle dynamic replace of controls

[Dimitris Papastamos]

This function can be used to replace or add controls at runtime.  It will
always try to add a given control if it does not already exist.

Signed-off-by: Dimitris Papastamos <dp@opensource.wolfsonmicro.com>
---
 include/sound/soc.h  |    2 ++
 sound/soc/soc-core.c |   33 +++++++++++++++++++++++++++++++++
 2 files changed, 35 insertions(+), 0 deletions(-)

diff --git a/include/sound/soc.h b/include/sound/soc.h
index bfa4836..a5bb531 100644
--- a/include/sound/soc.h
+++ b/include/sound/soc.h
@@ -344,6 +344,8 @@ struct snd_kcontrol *snd_soc_cnew(const struct snd_kcontrol_new *_template,
 				  const char *prefix);
 int snd_soc_add_controls(struct snd_soc_codec *codec,
 	const struct snd_kcontrol_new *controls, int num_controls);
+int snd_soc_replace_controls(struct snd_soc_codec *codec,
+	const struct snd_kcontrol_new *controls, int num_controls);
 int snd_soc_info_enum_double(struct snd_kcontrol *kcontrol,
 	struct snd_ctl_elem_info *uinfo);
 int snd_soc_info_enum_ext(struct snd_kcontrol *kcontrol,
diff --git a/sound/soc/soc-core.c b/sound/soc/soc-core.c
index 17efacd..e2aa0b4 100644
--- a/sound/soc/soc-core.c
+++ b/sound/soc/soc-core.c
@@ -2420,6 +2420,39 @@ int snd_soc_add_controls(struct snd_soc_codec *codec,
 EXPORT_SYMBOL_GPL(snd_soc_add_controls);
 
 /**
+ * snd_soc_replace_controls - replace an array of controls
+ * Convienience function to replace a list of controls.
+ *
+ * @codec: codec to replace controls of
+ * @controls: array of controls to replace
+ * @num_controls: number of elements in the array
+ *
+ * Return 0 for success, else error.
+ */
+int snd_soc_replace_controls(struct snd_soc_codec *codec,
+	const struct snd_kcontrol_new *controls, int num_controls)
+{
+	struct snd_card *card = codec->card->snd_card;
+	int err, i;
+
+	for (i = 0; i < num_controls; i++) {
+		const struct snd_kcontrol_new *control = &controls[i];
+		/* always add on replace if not already added */
+		err = snd_ctl_replace(card, snd_soc_cnew(control, codec,
+							 control->name,
+							 codec->name_prefix), true);
+		if (err < 0) {
+			dev_err(codec->dev, "%s: Failed to replace %s: %d\n",
+				codec->name, control->name, err);
+			return err;
+		}
+	}
+
+	return 0;
+}
+EXPORT_SYMBOL_GPL(snd_soc_replace_controls);
+
+/**
  * snd_soc_info_enum_double - enumerated double mixer info callback
  * @kcontrol: mixer control
  * @uinfo: control element information
-- 
1.7.4.1

Re: [PATCH 1/2 v4] ALSA: Add snd_ctl_replace() to dynamically replace a control

[Dimitris Papastamos]

On Wed, Mar 16, 2011 at 12:16:39PM +0000, Dimitris Papastamos wrote:
> Add a function to dynamically replace a given control.  If the
> control does not already exist, a third parameter is used to determine
> whether to actually add that control.  This is useful in cases where
> downloadable firmware at runtime can add or replace existing controls.
> A separate patch needs to be made to allow ALSA Mixer to render the
> replaced controls on the fly.
> 
> Signed-off-by: Dimitris Papastamos <dp@opensource.wolfsonmicro.com>

Hi,

What's the status with this patch?

Thanks,
Dimitris

Re: [PATCH 1/2 v4] ALSA: Add snd_ctl_replace() to dynamically replace a control

[Mark Brown]

On Thu, Mar 17, 2011 at 02:26:18PM +0000, Dimitris Papastamos wrote:
> On Wed, Mar 16, 2011 at 12:16:39PM +0000, Dimitris Papastamos wrote:

> What's the status with this patch?

Don't hassle people until at least a week or something (usually longer)
unless something is particularly urgent and/or you've a reason to expect
a prompter response.

Re: [PATCH 1/2 v4] ALSA: Add snd_ctl_replace() to dynamically replace a control

[Takashi Iwai]

At Thu, 17 Mar 2011 15:07:45 +0000,
Mark Brown wrote:
> 
> On Thu, Mar 17, 2011 at 02:26:18PM +0000, Dimitris Papastamos wrote:
> > On Wed, Mar 16, 2011 at 12:16:39PM +0000, Dimitris Papastamos wrote:
> 
> > What's the status with this patch?
> 
> Don't hassle people until at least a week or something (usually longer)
> unless something is particularly urgent and/or you've a reason to expect
> a prompter response.

Yeah, also right now it's the time to prepare for the next kernel,
so any new features are a bit postponed.
(Of course they can be kept in a different branch, but my first
 priority is the stabilization for the time being.)
 

Takashi

Re: [PATCH 1/2 v4] ALSA: Add snd_ctl_replace() to dynamically replace a control

[Takashi Iwai]

At Wed, 16 Mar 2011 12:16:39 +0000,
Dimitris Papastamos wrote:
> 
> Add a function to dynamically replace a given control.  If the
> control does not already exist, a third parameter is used to determine
> whether to actually add that control.  This is useful in cases where
> downloadable firmware at runtime can add or replace existing controls.
> A separate patch needs to be made to allow ALSA Mixer to render the
> replaced controls on the fly.
> 
> Signed-off-by: Dimitris Papastamos <dp@opensource.wolfsonmicro.com>

Now I applied this one to topic/misc branch with slight coding-style
fixes checkpatch complained.  But I didn't apply the patch for ASoC.

Marc, if you want to take it for ASoC, please pull topic/misc branch
into your tree.


thanks,

Takashi


> ---
>  include/sound/control.h |    1 +
>  sound/core/control.c    |   65 +++++++++++++++++++++++++++++++++++++++++++++++
>  2 files changed, 66 insertions(+), 0 deletions(-)
> 
> diff --git a/include/sound/control.h b/include/sound/control.h
> index e67db28..1c8b3ee 100644
> --- a/include/sound/control.h
> +++ b/include/sound/control.h
> @@ -113,6 +113,7 @@ struct snd_kcontrol *snd_ctl_new1(const struct snd_kcontrol_new * kcontrolnew, v
>  void snd_ctl_free_one(struct snd_kcontrol * kcontrol);
>  int snd_ctl_add(struct snd_card * card, struct snd_kcontrol * kcontrol);
>  int snd_ctl_remove(struct snd_card * card, struct snd_kcontrol * kcontrol);
> +int snd_ctl_replace(struct snd_card * card, struct snd_kcontrol * kcontrol, bool add_on_replace);
>  int snd_ctl_remove_id(struct snd_card * card, struct snd_ctl_elem_id *id);
>  int snd_ctl_rename_id(struct snd_card * card, struct snd_ctl_elem_id *src_id, struct snd_ctl_elem_id *dst_id);
>  int snd_ctl_activate_id(struct snd_card *card, struct snd_ctl_elem_id *id,
> diff --git a/sound/core/control.c b/sound/core/control.c
> index db51e4e..a8cae8a 100644
> --- a/sound/core/control.c
> +++ b/sound/core/control.c
> @@ -368,6 +368,71 @@ int snd_ctl_add(struct snd_card *card, struct snd_kcontrol *kcontrol)
>  EXPORT_SYMBOL(snd_ctl_add);
>  
>  /**
> + * snd_ctl_replace - replace the control instance of the card
> + * @card: the card instance
> + * @kcontrol: the control instance to replace
> + * @add_on_replace: add the control if not already added
> + *
> + * Replaces the given control.  If the given control does not exist
> + * and the add_on_replace flag is set, the control is added.  If the
> + * control exists, it is destroyed first.
> + *
> + * Returns zero if successful, or a negative error code on failure.
> + *
> + * It frees automatically the control which cannot be added or replaced.
> + */
> +int snd_ctl_replace(struct snd_card *card, struct snd_kcontrol *kcontrol,
> +		    bool add_on_replace)
> +{
> +	struct snd_ctl_elem_id id;
> +	unsigned int idx;
> +	struct snd_kcontrol *old;
> +	int ret;
> +
> +	if (!kcontrol)
> +		return -EINVAL;
> +	if (snd_BUG_ON(!card || !kcontrol->info)) {
> +		ret = -EINVAL;
> +		goto error;
> +	}
> +	id = kcontrol->id;
> +	down_write(&card->controls_rwsem);
> +	old = snd_ctl_find_id(card, &id);
> +	if (!old) {
> +		if (add_on_replace)
> +			goto add;
> +		up_write(&card->controls_rwsem);
> +		ret = -EINVAL;
> +		goto error;
> +	}
> +	ret = snd_ctl_remove(card, old);
> +	if (ret < 0) {
> +		up_write(&card->controls_rwsem);
> +		goto error;
> +	}
> +add:
> +	if (snd_ctl_find_hole(card, kcontrol->count) < 0) {
> +		up_write(&card->controls_rwsem);
> +		ret = -ENOMEM;
> +		goto error;
> +	}
> +	list_add_tail(&kcontrol->list, &card->controls);
> +	card->controls_count += kcontrol->count;
> +	kcontrol->id.numid = card->last_numid + 1;
> +	card->last_numid += kcontrol->count;
> +	up_write(&card->controls_rwsem);
> +	for (idx = 0; idx < kcontrol->count; idx++, id.index++, id.numid++)
> +		snd_ctl_notify(card, SNDRV_CTL_EVENT_MASK_ADD, &id);
> +	return 0;
> +
> +error:
> +	snd_ctl_free_one(kcontrol);
> +	return ret;
> +}
> +
> +EXPORT_SYMBOL(snd_ctl_replace);
> +
> +/**
>   * snd_ctl_remove - remove the control from the card and release it
>   * @card: the card instance
>   * @kcontrol: the control instance to remove
> -- 
> 1.7.4.1
> 

Re: [PATCH 1/2 v4] ALSA: Add snd_ctl_replace() to dynamically replace a control

[Dimitris Papastamos]

On Tue, Mar 22, 2011 at 04:17:51PM +0100, Takashi Iwai wrote:
> At Wed, 16 Mar 2011 12:16:39 +0000,
> Dimitris Papastamos wrote:
> > 
> > Add a function to dynamically replace a given control.  If the
> > control does not already exist, a third parameter is used to determine
> > whether to actually add that control.  This is useful in cases where
> > downloadable firmware at runtime can add or replace existing controls.
> > A separate patch needs to be made to allow ALSA Mixer to render the
> > replaced controls on the fly.
> > 
> > Signed-off-by: Dimitris Papastamos <dp@opensource.wolfsonmicro.com>
> 
> Now I applied this one to topic/misc branch with slight coding-style
> fixes checkpatch complained.  But I didn't apply the patch for ASoC.

Hi,

The reason why I did not fix those was because I tried to match the
style of sound/core/control.c.

Thanks,
Dimitris

Re: [PATCH 1/2 v4] ALSA: Add snd_ctl_replace() to dynamically replace a control

[Takashi Iwai]

At Tue, 22 Mar 2011 15:35:07 +0000,
Dimitris Papastamos wrote:
> 
> On Tue, Mar 22, 2011 at 04:17:51PM +0100, Takashi Iwai wrote:
> > At Wed, 16 Mar 2011 12:16:39 +0000,
> > Dimitris Papastamos wrote:
> > > 
> > > Add a function to dynamically replace a given control.  If the
> > > control does not already exist, a third parameter is used to determine
> > > whether to actually add that control.  This is useful in cases where
> > > downloadable firmware at runtime can add or replace existing controls.
> > > A separate patch needs to be made to allow ALSA Mixer to render the
> > > replaced controls on the fly.
> > > 
> > > Signed-off-by: Dimitris Papastamos <dp@opensource.wolfsonmicro.com>
> > 
> > Now I applied this one to topic/misc branch with slight coding-style
> > fixes checkpatch complained.  But I didn't apply the patch for ASoC.
> 
> Hi,
> 
> The reason why I did not fix those was because I tried to match the
> style of sound/core/control.c.

Yeah, it could be easily guessed.


Takashi