diff mbox series

[BlueZ,v2,1/2] Added initial code for handling VOCS

Message ID 20230607121342.6136-2-nitin.jadhav@nxp.com (mailing list archive)
State Superseded
Headers show
Series Code handling for VOCS service | expand

Checks

Context Check Description
tedd_an/pre-ci_am success Success
tedd_an/CheckPatch warning WARNING:LONG_LINE: line length of 93 exceeds 80 columns #596: FILE: src/shared/vcp.c:1268: + uint16_t value_handle, const uint8_t *value, uint16_t length, WARNING:LONG_LINE: line length of 89 exceeds 80 columns #614: FILE: src/shared/vcp.c:1340: + uint8_t att_ecode, const uint8_t *value, uint16_t length, WARNING:LONG_LINE: line length of 85 exceeds 80 columns #624: FILE: src/shared/vcp.c:1350: + DBG(vcp, "Unable to read Vol Offset State: error 0x%02x", att_ecode); WARNING:LONG_LINE: line length of 89 exceeds 80 columns #639: FILE: src/shared/vcp.c:1365: + uint8_t att_ecode, const uint8_t *value, uint16_t length, WARNING:LONG_LINE: line length of 88 exceeds 80 columns #649: FILE: src/shared/vcp.c:1375: + DBG(vcp, "Unable to read VOCS Audio Location: error 0x%02x", att_ecode); WARNING:LONG_LINE: line length of 89 exceeds 80 columns #664: FILE: src/shared/vcp.c:1390: + uint8_t att_ecode, const uint8_t *value, uint16_t length, WARNING:LONG_LINE: line length of 85 exceeds 80 columns #724: FILE: src/shared/vcp.c:1599: + vcp_voffset_state_notify, NULL); WARNING:LONG_LINE: line length of 81 exceeds 80 columns #739: FILE: src/shared/vcp.c:1614: + vcp_read_value(vcp, value_handle, read_vocs_audio_location, vcp); WARNING:LONG_LINE: line length of 81 exceeds 80 columns #742: FILE: src/shared/vcp.c:1617: + vcp_audio_loc_notify, NULL); WARNING:LONG_LINE: line length of 83 exceeds 80 columns #769: FILE: src/shared/vcp.c:1644: + vcp_read_value(vcp, value_handle, read_vocs_audio_descriptor, vcp); WARNING:LONG_LINE: line length of 87 exceeds 80 columns #771: FILE: src/shared/vcp.c:1646: + vcp_audio_descriptor_notify, NULL); /github/workspace/src/src/13270609.patch total: 0 errors, 11 warnings, 676 lines checked NOTE: For some of the reported defects, checkpatch may be able to mechanically convert to the typical style using --fix or --fix-inplace. /github/workspace/src/src/13270609.patch has style problems, please review. NOTE: Ignored message types: COMMIT_MESSAGE COMPLEX_MACRO CONST_STRUCT FILE_PATH_CHANGES MISSING_SIGN_OFF PREFER_PACKED SPDX_LICENSE_TAG SPLIT_STRING SSCANF_TO_KSTRTO NOTE: If any of the errors are false positives, please report them to the maintainer, see CHECKPATCH in MAINTAINERS.
tedd_an/GitLint success Gitlint PASS
tedd_an/BuildEll success Build ELL PASS
tedd_an/BluezMake success Bluez Make PASS
tedd_an/MakeCheck success Bluez Make Check PASS
tedd_an/MakeDistcheck success Make Distcheck PASS
tedd_an/CheckValgrind success Check Valgrind PASS
tedd_an/CheckSmatch success CheckSparse PASS
tedd_an/bluezmakeextell success Make External ELL PASS
tedd_an/IncrementalBuild success Incremental Build PASS
tedd_an/ScanBuild warning ScanBuild: src/shared/vcp.c:1272:2: warning: Null pointer passed to 1st parameter expecting 'nonnull' memcpy(vocs_audio_loc_n, value, sizeof(uint32_t)); ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ 1 warning generated.

Commit Message

Nitin Jadhav June 7, 2023, 12:13 p.m. UTC
This adds implementation for VOCS service and characteristics
---
v2: Corrected prefixs and cosmetic changes (Luiz Augusto von Dentz)
---
 lib/uuid.h       |   5 +
 src/shared/vcp.c | 537 +++++++++++++++++++++++++++++++++++++++++++++++
 2 files changed, 542 insertions(+)

Comments

Paul Menzel June 7, 2023, 12:24 p.m. UTC | #1
Dear Nitin,


Thank you for your patch.

Am 07.06.23 um 14:13 schrieb Nitin Jadhav:

It’d be great if you used imperative mood in the commit message 
summary/title. Maybe:

Add initial VOCS code

> This adds implementation for VOCS service and characteristics

Please document the datasheet name and version, you used to write the code.

If you summarized the implementation, and also documented how you tested 
this, that’d be great.

> ---
> v2: Corrected prefixs and cosmetic changes (Luiz Augusto von Dentz)
> ---
>   lib/uuid.h       |   5 +
>   src/shared/vcp.c | 537 +++++++++++++++++++++++++++++++++++++++++++++++
>   2 files changed, 542 insertions(+)

[…]


Kind regards,

Paul
bluez.test.bot@gmail.com June 7, 2023, 1:37 p.m. UTC | #2
This is automated email and please do not reply to this email!

Dear submitter,

Thank you for submitting the patches to the linux bluetooth mailing list.
This is a CI test results with your patch series:
PW Link:https://patchwork.kernel.org/project/bluetooth/list/?series=754867

---Test result---

Test Summary:
CheckPatch                    FAIL      1.74 seconds
GitLint                       PASS      0.72 seconds
BuildEll                      PASS      27.11 seconds
BluezMake                     PASS      863.57 seconds
MakeCheck                     PASS      12.34 seconds
MakeDistcheck                 PASS      154.02 seconds
CheckValgrind                 PASS      255.60 seconds
CheckSmatch                   PASS      340.33 seconds
bluezmakeextell               PASS      102.67 seconds
IncrementalBuild              PASS      1417.56 seconds
ScanBuild                     WARNING   1055.29 seconds

Details
##############################
Test: CheckPatch - FAIL
Desc: Run checkpatch.pl script
Output:
[BlueZ,v2,1/2] Added initial code for handling VOCS
WARNING:LONG_LINE: line length of 93 exceeds 80 columns
#596: FILE: src/shared/vcp.c:1268:
+				uint16_t value_handle, const uint8_t *value, uint16_t length,

WARNING:LONG_LINE: line length of 89 exceeds 80 columns
#614: FILE: src/shared/vcp.c:1340:
+				uint8_t att_ecode, const uint8_t *value, uint16_t length,

WARNING:LONG_LINE: line length of 85 exceeds 80 columns
#624: FILE: src/shared/vcp.c:1350:
+		DBG(vcp, "Unable to read Vol Offset State: error 0x%02x", att_ecode);

WARNING:LONG_LINE: line length of 89 exceeds 80 columns
#639: FILE: src/shared/vcp.c:1365:
+				uint8_t att_ecode, const uint8_t *value, uint16_t length,

WARNING:LONG_LINE: line length of 88 exceeds 80 columns
#649: FILE: src/shared/vcp.c:1375:
+		DBG(vcp, "Unable to read VOCS Audio Location: error 0x%02x", att_ecode);

WARNING:LONG_LINE: line length of 89 exceeds 80 columns
#664: FILE: src/shared/vcp.c:1390:
+				uint8_t att_ecode, const uint8_t *value, uint16_t length,

WARNING:LONG_LINE: line length of 85 exceeds 80 columns
#724: FILE: src/shared/vcp.c:1599:
+						     vcp_voffset_state_notify, NULL);

WARNING:LONG_LINE: line length of 81 exceeds 80 columns
#739: FILE: src/shared/vcp.c:1614:
+		vcp_read_value(vcp, value_handle, read_vocs_audio_location, vcp);

WARNING:LONG_LINE: line length of 81 exceeds 80 columns
#742: FILE: src/shared/vcp.c:1617:
+						     vcp_audio_loc_notify, NULL);

WARNING:LONG_LINE: line length of 83 exceeds 80 columns
#769: FILE: src/shared/vcp.c:1644:
+		vcp_read_value(vcp, value_handle, read_vocs_audio_descriptor, vcp);

WARNING:LONG_LINE: line length of 87 exceeds 80 columns
#771: FILE: src/shared/vcp.c:1646:
+						    vcp_audio_descriptor_notify, NULL);

/github/workspace/src/src/13270609.patch total: 0 errors, 11 warnings, 676 lines checked

NOTE: For some of the reported defects, checkpatch may be able to
      mechanically convert to the typical style using --fix or --fix-inplace.

/github/workspace/src/src/13270609.patch has style problems, please review.

NOTE: Ignored message types: COMMIT_MESSAGE COMPLEX_MACRO CONST_STRUCT FILE_PATH_CHANGES MISSING_SIGN_OFF PREFER_PACKED SPDX_LICENSE_TAG SPLIT_STRING SSCANF_TO_KSTRTO

NOTE: If any of the errors are false positives, please report
      them to the maintainer, see CHECKPATCH in MAINTAINERS.


##############################
Test: ScanBuild - WARNING
Desc: Run Scan Build
Output:
src/shared/vcp.c:1272:2: warning: Null pointer passed to 1st parameter expecting 'nonnull'
        memcpy(vocs_audio_loc_n, value, sizeof(uint32_t));
        ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
1 warning generated.



---
Regards,
Linux Bluetooth
diff mbox series

Patch

diff --git a/lib/uuid.h b/lib/uuid.h
index 5cdfedb4b..cd3b3655f 100644
--- a/lib/uuid.h
+++ b/lib/uuid.h
@@ -179,6 +179,11 @@  extern "C" {
 #define VOL_CP_CHRC_UUID				0x2B7E
 #define VOL_FLAG_CHRC_UUID				0x2B7F
 
+#define VOCS_STATE_CHAR_UUID			0x2B80
+#define VOCS_AUDIO_LOC_CHRC_UUID		0x2B81
+#define VOCS_CP_CHRC_UUID			0x2B82
+#define VOCS_AUDIO_OP_DESC_CHAR_UUID		0x2B83
+
 #define GMCS_UUID                               0x1849
 #define MEDIA_PLAYER_NAME_CHRC_UUID             0x2b93
 #define MEDIA_TRACK_CHNGD_CHRC_UUID             0x2b96
diff --git a/src/shared/vcp.c b/src/shared/vcp.c
index 5459cf892..e9bd6e88b 100644
--- a/src/shared/vcp.c
+++ b/src/shared/vcp.c
@@ -36,9 +36,40 @@ 
 #define BT_ATT_ERROR_INVALID_CHANGE_COUNTER	0x80
 #define BT_ATT_ERROR_OPCODE_NOT_SUPPORTED	0x81
 
+#define BT_VCP_NA                   0x00000000
+#define BT_VCP_FRONT_LEFT           0x00000001
+#define BT_VCP_FRONT_RIGHT          0x00000002
+#define BT_VCP_FRONT_CENTER         0x00000004
+#define BT_VCP_LOW_FRQ_EFF_1        0x00000008
+#define BT_VCP_BACK_LEFT            0x00000010
+#define BT_VCP_BACK_RIGHT           0x00000020
+#define BT_VCP_FRONT_LEFT_CENTER    0x00000040
+#define BT_VCP_FRONT_RIGHT_CENTER   0x00000080
+#define BT_VCP_BACK_CENTER          0x00000100
+#define BT_VCP_LOW_FRQ_EFF_2        0x00000200
+#define BT_VCP_SIDE_LEFT            0x00000400
+#define BT_VCP_SIDE_RIGHT           0x00000800
+#define BT_VCP_TOP_FRONT_LEFT       0x00001000
+#define BT_VCP_TOP_FRONT_RIGHT      0x00002000
+#define BT_VCP_TOP_FRONT_CENTER     0x00004000
+#define BT_VCP_TOP_CENTER           0x00008000
+#define BT_VCP_TOP_BACK_LEFT        0x00010000
+#define BT_VCP_TOP_BACK_RIGHT       0x00020000
+#define BT_VCP_TOP_SIDE_LEFT        0x00040000
+#define BT_VCP_TOP_SIDE_RIGHT       0x00080000
+#define BT_VCP_TOP_BACK_CENTER      0x00100000
+#define BT_VCP_BOTTOM_FRONT_CENTER  0x00200000
+#define BT_VCP_BOTTOM_FRONT_LEFT    0x00400000
+#define BT_VCP_BOTTOM_FRONT_RIGHT   0x00800000
+#define BT_VCP_FRONT_LEFT_WIDE      0x01000000
+#define BT_VCP_FRONT_RIGHT_WIDE     0x02000000
+#define BT_VCP_LEFT_SURROUND        0x04000000
+#define BT_VCP_RIGHT_SURROUND       0x08000000
+
 struct bt_vcp_db {
 	struct gatt_db *db;
 	struct bt_vcs *vcs;
+	struct bt_vocs *vocs;
 };
 
 typedef void (*vcp_func_t)(struct bt_vcp *vcp, bool success, uint8_t att_ecode,
@@ -57,11 +88,21 @@  struct bt_vcs_param {
 	uint8_t	change_counter;
 } __packed;
 
+struct bt_vocs_param {
+	uint8_t	op;
+	uint8_t	change_counter;
+} __packed;
+
 struct bt_vcs_ab_vol {
 	uint8_t	change_counter;
 	uint8_t	vol_set;
 } __packed;
 
+struct bt_vocs_set_vol_off {
+	uint8_t	change_counter;
+	uint8_t	set_vol_offset;
+} __packed;
+
 struct bt_vcp_cb {
 	unsigned int id;
 	bt_vcp_func_t attached;
@@ -89,6 +130,10 @@  struct bt_vcp {
 	unsigned int vstate_id;
 	unsigned int vflag_id;
 
+	unsigned int state_id;
+	unsigned int audio_loc_id;
+	unsigned int ao_dec_id;
+
 	struct queue *notify;
 	struct queue *pending;
 
@@ -120,6 +165,27 @@  struct bt_vcs {
 	struct gatt_db_attribute *vf_ccc;
 };
 
+/* Contains local bt_vcp_db */
+struct vol_offset_state {
+	uint16_t vol_offset;
+	uint8_t counter;
+} __packed;
+
+struct bt_vocs {
+	struct bt_vcp_db *vdb;
+	struct vol_offset_state *vostate;
+	uint32_t vocs_audio_loc;
+	char *vocs_ao_dec;
+	struct gatt_db_attribute *service;
+	struct gatt_db_attribute *vos;
+	struct gatt_db_attribute *vos_ccc;
+	struct gatt_db_attribute *voal;
+	struct gatt_db_attribute *voal_ccc;
+	struct gatt_db_attribute *vo_cp;
+	struct gatt_db_attribute *voaodec;
+	struct gatt_db_attribute *voaodec_ccc;
+};
+
 static struct queue *vcp_db;
 static struct queue *vcp_cbs;
 static struct queue *sessions;
@@ -159,6 +225,17 @@  static struct vol_state *vdb_get_vstate(struct bt_vcp_db *vdb)
 	return NULL;
 }
 
+static struct vol_offset_state *vdb_get_vostate(struct bt_vcp_db *vdb)
+{
+	if (!vdb->vocs)
+		return NULL;
+
+	if (vdb->vocs->vostate)
+		return vdb->vocs->vostate;
+
+	return NULL;
+}
+
 static struct bt_vcs *vcp_get_vcs(struct bt_vcp *vcp)
 {
 	if (!vcp)
@@ -173,6 +250,20 @@  static struct bt_vcs *vcp_get_vcs(struct bt_vcp *vcp)
 	return vcp->rdb->vcs;
 }
 
+static struct bt_vocs *vcp_get_vocs(struct bt_vcp *vcp)
+{
+	if (!vcp)
+		return NULL;
+
+	if (vcp->rdb->vocs)
+		return vcp->rdb->vocs;
+
+	vcp->rdb->vocs = new0(struct bt_vocs, 1);
+	vcp->rdb->vocs->vdb = vcp->rdb;
+
+	return vcp->rdb->vocs;
+}
+
 static void vcp_detached(void *data, void *user_data)
 {
 	struct bt_vcp_cb *cb = data;
@@ -202,6 +293,7 @@  static void vcp_db_free(void *data)
 	gatt_db_unref(vdb->db);
 
 	free(vdb->vcs);
+	free(vdb->vocs);
 	free(vdb);
 }
 
@@ -583,6 +675,45 @@  static uint8_t vcs_mute(struct bt_vcs *vcs, struct bt_vcp *vcp,
 	return 0;
 }
 
+static uint8_t vocs_set_vol_offset(struct bt_vocs *vocs, struct bt_vcp *vcp,
+				struct iovec *iov)
+{
+	struct bt_vcp_db *vdb;
+	struct vol_offset_state *vstate;
+	struct bt_vocs_set_vol_off *req;
+
+	DBG(vcp, "Set Volume Offset");
+
+	vdb = vcp_get_vdb(vcp);
+	if (!vdb) {
+		DBG(vcp, "error: VDB not available");
+		return 0;
+	}
+
+	vstate = vdb_get_vostate(vdb);
+	if (!vstate) {
+		DBG(vcp, "error: VSTATE not available");
+		return 0;
+	}
+
+	req = iov_pull_mem(iov, sizeof(*req));
+	if (!req)
+		return 0;
+
+	if (req->change_counter != vstate->counter) {
+		DBG(vcp, "Change Counter Mismatch Volume not decremented!");
+		return BT_ATT_ERROR_INVALID_CHANGE_COUNTER;
+	}
+
+	vstate->vol_offset = req->set_vol_offset;
+	vstate->counter = -~vstate->counter; /*Increment Change Counter*/
+
+	gatt_db_attribute_notify(vdb->vocs->vos, (void *)vstate,
+				 sizeof(struct vol_offset_state),
+				 bt_vcp_get_att(vcp));
+	return 0;
+}
+
 #define	BT_VCS_REL_VOL_DOWN		0x00
 #define	BT_VCS_REL_VOL_UP		0x01
 #define	BT_VCS_UNMUTE_REL_VOL_DOWN	0x02
@@ -591,6 +722,8 @@  static uint8_t vcs_mute(struct bt_vcs *vcs, struct bt_vcp *vcp,
 #define	BT_VCS_UNMUTE			0x05
 #define	BT_VCS_MUTE			0x06
 
+#define BT_VOCS_SET_VOL_OFFSET	0x01
+
 #define VCS_OP(_str, _op, _size, _func) \
 	{ \
 		.str = _str, \
@@ -623,6 +756,26 @@  struct vcs_op_handler {
 	{}
 };
 
+#define VOCS_OP(_str, _op, _size, _func) \
+	{ \
+		.str = _str, \
+		.op = _op, \
+		.size = _size, \
+		.func = _func, \
+	}
+
+struct vocs_op_handler {
+	const char *str;
+	uint8_t	op;
+	size_t	size;
+	uint8_t	(*func)(struct bt_vocs *vocs, struct bt_vcp *vcp,
+			struct iovec *iov);
+} vocp_handlers[] = {
+	VOCS_OP("Set Volume Offset", BT_VOCS_SET_VOL_OFFSET,
+		sizeof(uint8_t), vocs_set_vol_offset),
+	{}
+};
+
 static void vcs_cp_write(struct gatt_db_attribute *attrib,
 				unsigned int id, uint16_t offset,
 				const uint8_t *value, size_t len,
@@ -683,6 +836,66 @@  respond:
 	gatt_db_attribute_write_result(attrib, id, ret);
 }
 
+static void vocs_cp_write(struct gatt_db_attribute *attrib,
+				unsigned int id, uint16_t offset,
+				const uint8_t *value, size_t len,
+				uint8_t opcode, struct bt_att *att,
+				void *user_data)
+{
+	struct bt_vocs *vocs = user_data;
+	struct bt_vcp *vcp = vcp_get_session(att, vocs->vdb->db);
+	struct iovec iov = {
+		.iov_base = (void *) value,
+		.iov_len = len,
+	};
+	uint8_t	*vcp_op;
+	struct vocs_op_handler *handler;
+	uint8_t ret = BT_ATT_ERROR_REQUEST_NOT_SUPPORTED;
+
+	DBG(vcp, "VOCP Control Point Write");
+
+	if (offset) {
+		DBG(vcp, "invalid offset %d", offset);
+		ret = BT_ATT_ERROR_INVALID_OFFSET;
+		goto respond;
+	}
+
+	if (len < sizeof(*vcp_op)) {
+		DBG(vcp, "invalid len %ld < %ld sizeof(*param)", len,
+							sizeof(*vcp_op));
+		ret = BT_ATT_ERROR_INVALID_ATTRIBUTE_VALUE_LEN;
+		goto respond;
+	}
+
+	vcp_op = iov_pull_mem(&iov, sizeof(*vcp_op));
+
+	for (handler = vocp_handlers; handler && handler->str; handler++) {
+		if (handler->op != *vcp_op)
+			continue;
+
+		if (iov.iov_len < handler->size) {
+			DBG(vcp, "invalid len %ld < %ld handler->size", len,
+			    handler->size);
+			ret = BT_ATT_ERROR_OPCODE_NOT_SUPPORTED;
+			goto respond;
+		}
+
+		break;
+	}
+
+	if (handler && handler->str) {
+		DBG(vcp, "%s", handler->str);
+
+		ret = handler->func(vocs, vcp, &iov);
+	} else {
+		DBG(vcp, "Unknown opcode 0x%02x", *vcp_op);
+		ret = BT_ATT_ERROR_OPCODE_NOT_SUPPORTED;
+	}
+
+respond:
+	gatt_db_attribute_write_result(attrib, id, ret);
+}
+
 static void vcs_state_read(struct gatt_db_attribute *attrib,
 				unsigned int id, uint16_t offset,
 				uint8_t opcode, struct bt_att *att,
@@ -698,6 +911,21 @@  static void vcs_state_read(struct gatt_db_attribute *attrib,
 							iov.iov_len);
 }
 
+static void vocs_state_read(struct gatt_db_attribute *attrib,
+				unsigned int id, uint16_t offset,
+				uint8_t opcode, struct bt_att *att,
+				void *user_data)
+{
+	struct bt_vocs *vocs = user_data;
+	struct iovec iov;
+
+	iov.iov_base = vocs->vostate;
+	iov.iov_len = sizeof(*vocs->vostate);
+
+	gatt_db_attribute_read_result(attrib, id, 0, iov.iov_base,
+							iov.iov_len);
+}
+
 static void vcs_flag_read(struct gatt_db_attribute *attrib,
 				unsigned int id, uint16_t offset,
 				uint8_t opcode, struct bt_att *att,
@@ -713,6 +941,36 @@  static void vcs_flag_read(struct gatt_db_attribute *attrib,
 							iov.iov_len);
 }
 
+static void vocs_voal_read(struct gatt_db_attribute *attrib,
+				unsigned int id, uint16_t offset,
+				uint8_t opcode, struct bt_att *att,
+				void *user_data)
+{
+	struct bt_vocs *vocs = user_data;
+	struct iovec iov;
+
+	iov.iov_base = &vocs->vocs_audio_loc;
+	iov.iov_len = sizeof(vocs->vocs_audio_loc);
+
+	gatt_db_attribute_read_result(attrib, id, 0, iov.iov_base,
+							iov.iov_len);
+}
+
+static void vocs_voaodec_read(struct gatt_db_attribute *attrib,
+				unsigned int id, uint16_t offset,
+				uint8_t opcode, struct bt_att *att,
+				void *user_data)
+{
+	struct bt_vocs *vocs = user_data;
+	struct iovec iov;
+
+	iov.iov_base = &vocs->vocs_ao_dec;
+	iov.iov_len = strlen(vocs->vocs_ao_dec);
+
+	gatt_db_attribute_read_result(attrib, id, 0, iov.iov_base,
+							iov.iov_len);
+}
+
 static struct bt_vcs *vcs_new(struct gatt_db *db)
 {
 	struct bt_vcs *vcs;
@@ -771,6 +1029,74 @@  static struct bt_vcs *vcs_new(struct gatt_db *db)
 	return vcs;
 }
 
+static struct bt_vocs *vocs_new(struct gatt_db *db)
+{
+	struct bt_vocs *vocs;
+	struct vol_offset_state *vostate;
+	bt_uuid_t uuid;
+
+	if (!db)
+		return NULL;
+
+	vocs = new0(struct bt_vocs, 1);
+
+	vostate = new0(struct vol_offset_state, 1);
+
+	vocs->vostate = vostate;
+	vocs->vocs_audio_loc = BT_VCP_FRONT_LEFT;
+	vocs->vocs_ao_dec = "Left Speaker";
+
+	/* Populate DB with VOCS attributes */
+	bt_uuid16_create(&uuid, VOL_OFFSET_CS_UUID);
+	vocs->service = gatt_db_add_service(db, &uuid, true, 9);
+
+	bt_uuid16_create(&uuid, VOCS_STATE_CHAR_UUID);
+	vocs->vos = gatt_db_service_add_characteristic(vocs->service,
+					&uuid,
+					BT_ATT_PERM_READ,
+					BT_GATT_CHRC_PROP_READ |
+					BT_GATT_CHRC_PROP_NOTIFY,
+					vocs_state_read, NULL,
+					vocs);
+
+	vocs->vos_ccc = gatt_db_service_add_ccc(vocs->service,
+					BT_ATT_PERM_READ | BT_ATT_PERM_WRITE);
+
+	bt_uuid16_create(&uuid, VOCS_AUDIO_LOC_CHRC_UUID);
+	vocs->voal = gatt_db_service_add_characteristic(vocs->service,
+					&uuid,
+					BT_ATT_PERM_READ,
+					BT_GATT_CHRC_PROP_READ |
+					BT_GATT_CHRC_PROP_NOTIFY,
+					vocs_voal_read, NULL,
+					vocs);
+
+	vocs->voal_ccc = gatt_db_service_add_ccc(vocs->service,
+					BT_ATT_PERM_READ | BT_ATT_PERM_WRITE);
+
+	bt_uuid16_create(&uuid, VOCS_CP_CHRC_UUID);
+	vocs->vo_cp = gatt_db_service_add_characteristic(vocs->service,
+					&uuid,
+					BT_ATT_PERM_WRITE,
+					BT_GATT_CHRC_PROP_WRITE,
+					NULL, vocs_cp_write,
+					vocs);
+
+	bt_uuid16_create(&uuid, VOCS_AUDIO_OP_DESC_CHAR_UUID);
+	vocs->voaodec = gatt_db_service_add_characteristic(vocs->service,
+					&uuid,
+					BT_ATT_PERM_READ,
+					BT_GATT_CHRC_PROP_READ |
+					BT_GATT_CHRC_PROP_NOTIFY,
+					vocs_voaodec_read, NULL,
+					vocs);
+
+	vocs->voaodec_ccc = gatt_db_service_add_ccc(vocs->service,
+					BT_ATT_PERM_READ | BT_ATT_PERM_WRITE);
+
+	return vocs;
+}
+
 static struct bt_vcp_db *vcp_db_new(struct gatt_db *db)
 {
 	struct bt_vcp_db *vdb;
@@ -787,6 +1113,9 @@  static struct bt_vcp_db *vcp_db_new(struct gatt_db *db)
 	vdb->vcs = vcs_new(db);
 	vdb->vcs->vdb = vdb;
 
+	vdb->vocs = vocs_new(db);
+	vdb->vocs->vdb = vdb;
+
 	queue_push_tail(vcp_db, vdb);
 
 	return vdb;
@@ -911,6 +1240,41 @@  static void vcp_vstate_notify(struct bt_vcp *vcp, uint16_t value_handle,
 	DBG(vcp, "Vol Counter 0x%x", vstate.counter);
 }
 
+static void vcp_voffset_state_notify(struct bt_vcp *vcp, uint16_t value_handle,
+				const uint8_t *value, uint16_t length,
+				void *user_data)
+{
+	struct vol_offset_state vostate;
+
+	memcpy(&vostate, value, sizeof(struct vol_offset_state));
+
+	DBG(vcp, "Vol Offset 0x%x", vostate.vol_offset);
+	DBG(vcp, "Vol Offset Counter 0x%x", vostate.counter);
+}
+
+static void vcp_audio_loc_notify(struct bt_vcp *vcp, uint16_t value_handle,
+				const uint8_t *value, uint16_t length,
+				void *user_data)
+{
+	uint32_t *vocs_audio_loc_n = 0;
+
+	memcpy(vocs_audio_loc_n, value, sizeof(uint32_t));
+
+	DBG(vcp, "VOCS Audio Location 0x%x", *vocs_audio_loc_n);
+}
+
+
+static void vcp_audio_descriptor_notify(struct bt_vcp *vcp,
+				uint16_t value_handle, const uint8_t *value, uint16_t length,
+				void *user_data)
+{
+	char vocs_audio_dec_n[256] = {'\0'};
+
+	memcpy(vocs_audio_dec_n, value, length);
+
+	DBG(vcp, "VOCS Audio Descriptor 0x%s", *vocs_audio_dec_n);
+}
+
 static void vcp_vflag_notify(struct bt_vcp *vcp, uint16_t value_handle,
 			     const uint8_t *value, uint16_t length,
 			     void *user_data)
@@ -972,6 +1336,81 @@  static void read_vol_state(struct bt_vcp *vcp, bool success, uint8_t att_ecode,
 	DBG(vcp, "Vol Counter:%x", vs->counter);
 }
 
+static void read_vol_offset_state(struct bt_vcp *vcp, bool success,
+				uint8_t att_ecode, const uint8_t *value, uint16_t length,
+				void *user_data)
+{
+	struct vol_offset_state *vos;
+	struct iovec iov = {
+		.iov_base = (void *) value,
+		.iov_len = length,
+	};
+
+	if (!success) {
+		DBG(vcp, "Unable to read Vol Offset State: error 0x%02x", att_ecode);
+		return;
+	}
+
+	vos = iov_pull_mem(&iov, sizeof(*vos));
+	if (!vos) {
+		DBG(vcp, "Unable to get Vol Offset State");
+		return;
+	}
+
+	DBG(vcp, "Vol Set:%x", vos->vol_offset);
+	DBG(vcp, "Vol Counter:%x", vos->counter);
+}
+
+static void read_vocs_audio_location(struct bt_vcp *vcp, bool success,
+				uint8_t att_ecode, const uint8_t *value, uint16_t length,
+				void *user_data)
+{
+	uint32_t *vocs_audio_loc;
+	struct iovec iov = {
+		.iov_base = (void *) value,
+		.iov_len = length,
+	};
+
+	if (!success) {
+		DBG(vcp, "Unable to read VOCS Audio Location: error 0x%02x", att_ecode);
+		return;
+	}
+
+	vocs_audio_loc = iov_pull_mem(&iov, sizeof(uint32_t));
+	if (!*vocs_audio_loc) {
+		DBG(vcp, "Unable to get VOCS Audio Location");
+		return;
+	}
+
+	DBG(vcp, "VOCS Audio Loc:%x", *vocs_audio_loc);
+}
+
+
+static void read_vocs_audio_descriptor(struct bt_vcp *vcp, bool success,
+				uint8_t att_ecode, const uint8_t *value, uint16_t length,
+				void *user_data)
+{
+	char *vocs_ao_dec_r;
+	struct iovec iov = {
+		.iov_base = (void *) value,
+		.iov_len = length,
+	};
+
+	if (!success) {
+		DBG(vcp, "Unable to read VOCS Audio Descriptor: error 0x%02x",
+			att_ecode);
+		return;
+	}
+
+	vocs_ao_dec_r = iov_pull_mem(&iov, length);
+	if (!*vocs_ao_dec_r) {
+		DBG(vcp, "Unable to get VOCS Audio Descriptor");
+		return;
+	}
+
+	DBG(vcp, "VOCS Audio Descriptor:%s", *vocs_ao_dec_r);
+}
+
 static void vcp_pending_destroy(void *data)
 {
 	struct bt_vcp_pending *pending = data;
@@ -1128,6 +1567,88 @@  static void foreach_vcs_char(struct gatt_db_attribute *attr, void *user_data)
 	}
 }
 
+static void foreach_vocs_char(struct gatt_db_attribute *attr, void *user_data)
+{
+	struct bt_vcp *vcp = user_data;
+	uint16_t value_handle;
+	bt_uuid_t uuid, uuid_vostate, uuid_audio_loc, uuid_vo_cp,
+			uuid_audio_op_decs;
+	struct bt_vocs *vocs;
+
+	if (!gatt_db_attribute_get_char_data(attr, NULL, &value_handle,
+						NULL, NULL, &uuid))
+		return;
+
+	bt_uuid16_create(&uuid_vostate, VOCS_STATE_CHAR_UUID);
+	bt_uuid16_create(&uuid_audio_loc, VOCS_AUDIO_LOC_CHRC_UUID);
+	bt_uuid16_create(&uuid_vo_cp, VOCS_CP_CHRC_UUID);
+	bt_uuid16_create(&uuid_audio_op_decs, VOCS_AUDIO_OP_DESC_CHAR_UUID);
+
+	if (!bt_uuid_cmp(&uuid, &uuid_vostate)) {
+		DBG(vcp, "VOCS Vol state found: handle 0x%04x", value_handle);
+
+		vocs = vcp_get_vocs(vcp);
+		if (!vocs || vocs->vos)
+			return;
+
+		vocs->vos = attr;
+
+		vcp_read_value(vcp, value_handle, read_vol_offset_state, vcp);
+
+		vcp->state_id = vcp_register_notify(vcp, value_handle,
+						     vcp_voffset_state_notify, NULL);
+
+		return;
+	}
+
+	if (!bt_uuid_cmp(&uuid, &uuid_audio_loc)) {
+		DBG(vcp, "VOCS Volume Audio Location found: handle 0x%04x",
+			value_handle);
+
+		vocs = vcp_get_vocs(vcp);
+		if (!vocs || vocs->voal)
+			return;
+
+		vocs->voal = attr;
+
+		vcp_read_value(vcp, value_handle, read_vocs_audio_location, vcp);
+
+		vcp->audio_loc_id = vcp_register_notify(vcp, value_handle,
+						     vcp_audio_loc_notify, NULL);
+
+		return;
+	}
+
+	if (!bt_uuid_cmp(&uuid, &uuid_vo_cp)) {
+		DBG(vcp, "VOCS Volume CP found: handle 0x%04x", value_handle);
+
+		vocs = vcp_get_vocs(vcp);
+		if (!vocs || vocs->vo_cp)
+			return;
+
+		vocs->vo_cp = attr;
+
+		return;
+	}
+
+	if (!bt_uuid_cmp(&uuid, &uuid_audio_op_decs)) {
+		DBG(vcp, "VOCS Vol Audio Descriptor found: handle 0x%04x",
+			value_handle);
+
+		vocs = vcp_get_vocs(vcp);
+		if (!vocs || vocs->voaodec)
+			return;
+
+		vocs->voaodec = attr;
+
+		vcp_read_value(vcp, value_handle, read_vocs_audio_descriptor, vcp);
+		vcp->ao_dec_id = vcp_register_notify(vcp, value_handle,
+						    vcp_audio_descriptor_notify, NULL);
+
+	}
+
+}
+
 static void foreach_vcs_service(struct gatt_db_attribute *attr,
 						void *user_data)
 {
@@ -1141,6 +1662,19 @@  static void foreach_vcs_service(struct gatt_db_attribute *attr,
 	gatt_db_service_foreach_char(attr, foreach_vcs_char, vcp);
 }
 
+static void foreach_vocs_service(struct gatt_db_attribute *attr,
+						void *user_data)
+{
+	struct bt_vcp *vcp = user_data;
+	struct bt_vocs *vocs = vcp_get_vocs(vcp);
+
+	vocs->service = attr;
+
+	gatt_db_service_set_claimed(attr, true);
+
+	gatt_db_service_foreach_char(attr, foreach_vocs_char, vcp);
+}
+
 bool bt_vcp_attach(struct bt_vcp *vcp, struct bt_gatt_client *client)
 {
 	bt_uuid_t uuid;
@@ -1163,6 +1697,9 @@  bool bt_vcp_attach(struct bt_vcp *vcp, struct bt_gatt_client *client)
 	bt_uuid16_create(&uuid, VCS_UUID);
 	gatt_db_foreach_service(vcp->ldb->db, &uuid, foreach_vcs_service, vcp);
 
+	bt_uuid16_create(&uuid, VOL_OFFSET_CS_UUID);
+	gatt_db_foreach_service(vcp->ldb->db, &uuid, foreach_vocs_service, vcp);
+
 	return true;
 }