[PATCH v1] ALSA: aoa: Constify struct codec_connection

[PATCH v1] ALSA: aoa: Constify struct codec_connection

[Christophe JAILLET]

'struct codec_connection' are not modified in this driver.

Constifying these structures moves some data to a read-only section, so
increases overall security.

On a x86_64, with allmodconfig:
Before:
======
   text	   data	    bss	    dec	    hex	filename
  10034	   3392	     12	  13438	   347e	sound/aoa/fabrics/layout.o

After:
=====
   text	   data	    bss	    dec	    hex	filename
  10370	   3040	     12	  13422	   346e	sound/aoa/fabrics/layout.o

Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
---
Compile tested only.

The fabric_data field in struct aoa_codecis is only used in
sound/aoa/fabrics/layout.c, so there should be no side effect for other
files that include sound/aoa/aoa.h
---
 sound/aoa/aoa.h            |  2 +-
 sound/aoa/fabrics/layout.c | 28 ++++++++++++++--------------
 2 files changed, 15 insertions(+), 15 deletions(-)

diff --git a/sound/aoa/aoa.h b/sound/aoa/aoa.h
index badff9f7cd54..b92593f170ca 100644
--- a/sound/aoa/aoa.h
+++ b/sound/aoa/aoa.h
@@ -48,7 +48,7 @@ struct aoa_codec {
 	u32 connected;
 
 	/* data the fabric can associate with this structure */
-	void *fabric_data;
+	const void *fabric_data;
 
 	/* private! */
 	struct list_head list;
diff --git a/sound/aoa/fabrics/layout.c b/sound/aoa/fabrics/layout.c
index c18b55305294..c3ebb6de4789 100644
--- a/sound/aoa/fabrics/layout.c
+++ b/sound/aoa/fabrics/layout.c
@@ -55,7 +55,7 @@ struct codec_connection {
 
 struct codec_connect_info {
 	char *name;
-	struct codec_connection *connections;
+	const struct codec_connection *connections;
 };
 
 #define LAYOUT_FLAG_COMBO_LINEOUT_SPDIF	(1<<0)
@@ -116,7 +116,7 @@ MODULE_ALIAS("aoa-device-id-35");
 MODULE_ALIAS("aoa-device-id-44");
 
 /* onyx with all but microphone connected */
-static struct codec_connection onyx_connections_nomic[] = {
+static const struct codec_connection onyx_connections_nomic[] = {
 	{
 		.connected = CC_SPEAKERS | CC_HEADPHONE | CC_LINEOUT,
 		.codec_bit = 0,
@@ -133,7 +133,7 @@ static struct codec_connection onyx_connections_nomic[] = {
 };
 
 /* onyx on machines without headphone */
-static struct codec_connection onyx_connections_noheadphones[] = {
+static const struct codec_connection onyx_connections_noheadphones[] = {
 	{
 		.connected = CC_SPEAKERS | CC_LINEOUT |
 			     CC_LINEOUT_LABELLED_HEADPHONE,
@@ -157,7 +157,7 @@ static struct codec_connection onyx_connections_noheadphones[] = {
 };
 
 /* onyx on machines with real line-out */
-static struct codec_connection onyx_connections_reallineout[] = {
+static const struct codec_connection onyx_connections_reallineout[] = {
 	{
 		.connected = CC_SPEAKERS | CC_LINEOUT | CC_HEADPHONE,
 		.codec_bit = 0,
@@ -174,7 +174,7 @@ static struct codec_connection onyx_connections_reallineout[] = {
 };
 
 /* tas on machines without line out */
-static struct codec_connection tas_connections_nolineout[] = {
+static const struct codec_connection tas_connections_nolineout[] = {
 	{
 		.connected = CC_SPEAKERS | CC_HEADPHONE,
 		.codec_bit = 0,
@@ -191,7 +191,7 @@ static struct codec_connection tas_connections_nolineout[] = {
 };
 
 /* tas on machines with neither line out nor line in */
-static struct codec_connection tas_connections_noline[] = {
+static const struct codec_connection tas_connections_noline[] = {
 	{
 		.connected = CC_SPEAKERS | CC_HEADPHONE,
 		.codec_bit = 0,
@@ -204,7 +204,7 @@ static struct codec_connection tas_connections_noline[] = {
 };
 
 /* tas on machines without microphone */
-static struct codec_connection tas_connections_nomic[] = {
+static const struct codec_connection tas_connections_nomic[] = {
 	{
 		.connected = CC_SPEAKERS | CC_HEADPHONE | CC_LINEOUT,
 		.codec_bit = 0,
@@ -217,7 +217,7 @@ static struct codec_connection tas_connections_nomic[] = {
 };
 
 /* tas on machines with everything connected */
-static struct codec_connection tas_connections_all[] = {
+static const struct codec_connection tas_connections_all[] = {
 	{
 		.connected = CC_SPEAKERS | CC_HEADPHONE | CC_LINEOUT,
 		.codec_bit = 0,
@@ -233,7 +233,7 @@ static struct codec_connection tas_connections_all[] = {
 	{} /* terminate array by .connected == 0 */
 };
 
-static struct codec_connection toonie_connections[] = {
+static const struct codec_connection toonie_connections[] = {
 	{
 		.connected = CC_SPEAKERS | CC_HEADPHONE,
 		.codec_bit = 0,
@@ -241,7 +241,7 @@ static struct codec_connection toonie_connections[] = {
 	{} /* terminate array by .connected == 0 */
 };
 
-static struct codec_connection topaz_input[] = {
+static const struct codec_connection topaz_input[] = {
 	{
 		.connected = CC_DIGITALIN,
 		.codec_bit = 0,
@@ -249,7 +249,7 @@ static struct codec_connection topaz_input[] = {
 	{} /* terminate array by .connected == 0 */
 };
 
-static struct codec_connection topaz_output[] = {
+static const struct codec_connection topaz_output[] = {
 	{
 		.connected = CC_DIGITALOUT,
 		.codec_bit = 1,
@@ -257,7 +257,7 @@ static struct codec_connection topaz_output[] = {
 	{} /* terminate array by .connected == 0 */
 };
 
-static struct codec_connection topaz_inout[] = {
+static const struct codec_connection topaz_inout[] = {
 	{
 		.connected = CC_DIGITALIN,
 		.codec_bit = 0,
@@ -772,7 +772,7 @@ static int check_codec(struct aoa_codec *codec,
 {
 	const u32 *ref;
 	char propname[32];
-	struct codec_connection *cc;
+	const struct codec_connection *cc;
 
 	/* if the codec has a 'codec' node, we require a reference */
 	if (of_node_name_eq(codec->node, "codec")) {
@@ -895,7 +895,7 @@ static void layout_notify(void *data)
 
 static void layout_attached_codec(struct aoa_codec *codec)
 {
-	struct codec_connection *cc;
+	const struct codec_connection *cc;
 	struct snd_kcontrol *ctl;
 	int headphones, lineout;
 	struct layout_dev *ldev = layout_device;
-- 
2.53.0

Re: [PATCH v1] ALSA: aoa: Constify struct codec_connection

[Takashi Iwai]

On Thu, 26 Feb 2026 21:44:10 +0100,
Christophe JAILLET wrote:
> 
> 'struct codec_connection' are not modified in this driver.
> 
> Constifying these structures moves some data to a read-only section, so
> increases overall security.
> 
> On a x86_64, with allmodconfig:
> Before:
> ======
>    text	   data	    bss	    dec	    hex	filename
>   10034	   3392	     12	  13438	   347e	sound/aoa/fabrics/layout.o
> 
> After:
> =====
>    text	   data	    bss	    dec	    hex	filename
>   10370	   3040	     12	  13422	   346e	sound/aoa/fabrics/layout.o
> 
> Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
> ---
> Compile tested only.
> 
> The fabric_data field in struct aoa_codecis is only used in
> sound/aoa/fabrics/layout.c, so there should be no side effect for other
> files that include sound/aoa/aoa.h

Applied to for-next branch now.  Thanks.


Takashi