Bluetooth: Allow querying of supported offload codecs over SCO socket

Add BT_CODEC option for getsockopt systemcall to get the details
of offload codecs supported over SCO socket

Signed-off-by: Kiran K <kiran.k@intel.com>
Reviewed-by: Chethan T N <chethan.tumkur.narayan@intel.com>
Reviewed-by: Srivatsa Ravishankar <ravishankar.srivatsa@intel.com>
Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>

include/net/bluetooth/bluetooth.h

@@ -153,6 +153,26 @@ struct bt_voice {
 
 #define BT_SCM_PKT_STATUS	0x03
 
+#define BT_CODEC	19
+
+struct	bt_codec_caps {
+	__u8	len;
+	__u8	data[];
+} __packed;
+
+struct bt_codec {
+	__u8	id;
+	__u16	cid;
+	__u16	vid;
+	__u8	data_path;
+	__u8	num_caps;
+} __packed;
+
+struct bt_codecs {
+	__u8		num_codecs;
+	struct bt_codec	codecs[];
+} __packed;
+
 __printf(1, 2)
 void bt_info(const char *fmt, ...);
 __printf(1, 2)

include/net/bluetooth/hci.h

@@ -331,6 +331,7 @@ enum {
 	HCI_CMD_PENDING,
 	HCI_FORCE_NO_MITM,
 	HCI_QUALITY_REPORT,
+	HCI_OFFLOAD_CODECS_ENABLED,
 
 	__HCI_NUM_FLAGS,
 };
@@ -2622,6 +2623,9 @@ static inline struct hci_sco_hdr *hci_sco_hdr(const struct sk_buff *skb)
 #define hci_iso_data_len(h)		((h) & 0x3fff)
 #define hci_iso_data_flags(h)		((h) >> 14)
 
+/* codec transport types */
+#define HCI_TRANSPORT_SCO_ESCO	0x01
+
 /* le24 support */
 static inline void hci_cpu_to_le24(__u32 val, __u8 dst[3])
 {

include/net/bluetooth/hci_core.h

@@ -619,6 +619,7 @@ struct hci_dev {
 	void (*cmd_timeout)(struct hci_dev *hdev);
 	bool (*prevent_wake)(struct hci_dev *hdev);
 	int (*set_quality_report)(struct hci_dev *hdev, bool enable);
+	int (*get_data_path_id)(struct hci_dev *hdev, __u8 *data_path);
 };
 
 #define HCI_PHY_HANDLE(handle)	(handle & 0xff)

net/bluetooth/sco.c

@@ -972,6 +972,12 @@ static int sco_sock_getsockopt(struct socket *sock, int level, int optname,
 	struct bt_voice voice;
 	u32 phys;
 	int pkt_status;
+	int buf_len;
+	struct codec_list *c;
+	u8 num_codecs, i, __user *ptr;
+	struct hci_dev *hdev;
+	struct hci_codec_caps *caps;
+	struct bt_codec codec;
 
 	BT_DBG("sk %p", sk);
 
@@ -1036,6 +1042,101 @@ static int sco_sock_getsockopt(struct socket *sock, int level, int optname,
 			err = -EFAULT;
 		break;
 
+	case BT_CODEC:
+		num_codecs = 0;
+		buf_len = 0;
+
+		hdev = hci_get_route(&sco_pi(sk)->dst, &sco_pi(sk)->src, BDADDR_BREDR);
+		if (!hdev) {
+			err = -EBADFD;
+			break;
+		}
+
+		if (!hci_dev_test_flag(hdev, HCI_OFFLOAD_CODECS_ENABLED)) {
+			hci_dev_put(hdev);
+			err = -EOPNOTSUPP;
+			break;
+		}
+
+		if (!hdev->get_data_path_id) {
+			hci_dev_put(hdev);
+			err = -EOPNOTSUPP;
+			break;
+		}
+
+		/* find total buffer size required to copy codec + caps */
+		hci_dev_lock(hdev);
+		list_for_each_entry(c, &hdev->local_codecs, list) {
+			if (c->transport != HCI_TRANSPORT_SCO_ESCO)
+				continue;
+			num_codecs++;
+			for (i = 0, caps = c->caps; i < c->num_caps; i++) {
+				buf_len += 1 + caps->len;
+				caps = (void *)&caps->data[caps->len];
+			}
+			buf_len += sizeof(struct bt_codec);
+		}
+		hci_dev_unlock(hdev);
+
+		buf_len += sizeof(struct bt_codecs);
+		if (buf_len > len) {
+			hci_dev_put(hdev);
+			err = -ENOBUFS;
+			break;
+		}
+		ptr = optval;
+
+		if (put_user(num_codecs, ptr)) {
+			hci_dev_put(hdev);
+			err = -EFAULT;
+			break;
+		}
+		ptr += sizeof(num_codecs);
+
+		/* Iterate all the codecs supported over SCO and populate
+		 * codec data
+		 */
+		hci_dev_lock(hdev);
+		list_for_each_entry(c, &hdev->local_codecs, list) {
+			if (c->transport != HCI_TRANSPORT_SCO_ESCO)
+				continue;
+
+			codec.id = c->id;
+			codec.cid = c->cid;
+			codec.vid = c->vid;
+			err = hdev->get_data_path_id(hdev, &codec.data_path);
+			if (err < 0)
+				break;
+			codec.num_caps = c->num_caps;
+			if (copy_to_user(ptr, &codec, sizeof(codec))) {
+				err = -EFAULT;
+				break;
+			}
+			ptr += sizeof(codec);
+
+			/* find codec capabilities data length */
+			len = 0;
+			for (i = 0, caps = c->caps; i < c->num_caps; i++) {
+				len += 1 + caps->len;
+				caps = (void *)&caps->data[caps->len];
+			}
+
+			/* copy codec capabilities data */
+			if (len && copy_to_user(ptr, c->caps, len)) {
+				err = -EFAULT;
+				break;
+			}
+			ptr += len;
+		}
+
+		if (!err && put_user(buf_len, optlen))
+			err = -EFAULT;
+
+		hci_dev_unlock(hdev);
+		hci_dev_put(hdev);
+
+		break;
+
 	default:
 		err = -ENOPROTOOPT;
 		break;