Bluetooth: Enumerate local supported codec and cache details

Move reading of supported local codecs into a separate init function,
query codecs capabilities and cache the data

Signed-off-by: Kiran K <[e-mail]>
Signed-off-by: Chethan T N <[e-mail]>
Signed-off-by: Srivatsa Ravishankar <[e-mail]>
Signed-off-by: Luiz Augusto von Dentz <[e-mail]>

include/net/bluetooth/hci.h

···
 } __packed;
 
 #define HCI_OP_READ_LOCAL_CODECS	0x100b
+struct hci_std_codecs {
+	__u8	num;
+	__u8	codec[];
+} __packed;
+
+struct hci_vnd_codec {
+	/* company id */
+	__le16	cid;
+	/* vendor codec id */
+	__le16	vid;
+} __packed;
+
+struct hci_vnd_codecs {
+	__u8	num;
+	struct hci_vnd_codec codec[];
+} __packed;
+
+struct hci_rp_read_local_supported_codecs {
+	__u8	status;
+	struct hci_std_codecs std_codecs;
+	struct hci_vnd_codecs vnd_codecs;
+} __packed;
 
 #define HCI_OP_READ_LOCAL_PAIRING_OPTS	0x100c
 struct hci_rp_read_local_pairing_opts {
 	__u8     status;
 	__u8     pairing_opts;
 	__u8     max_key_size;
+} __packed;
+
+#define HCI_OP_READ_LOCAL_CODEC_CAPS	0x100e
+struct hci_op_read_local_codec_caps {
+	__u8	id;
+	__le16	cid;
+	__le16	vid;
+	__u8	transport;
+	__u8	direction;
+} __packed;
+
+struct hci_codec_caps {
+	__u8	len;
+	__u8	data[];
+} __packed;
+
+struct hci_rp_read_local_codec_caps {
+	__u8	status;
+	__u8	num_caps;
 } __packed;
 
 #define HCI_OP_READ_PAGE_SCAN_ACTIVITY	0x0c1b

include/net/bluetooth/hci_core.h

···
 	u8 bdaddr_type;
 };
 
+struct codec_list {
+	struct list_head list;
+	u8	id;
+	__u16	cid;
+	__u16	vid;
+	u8	transport;
+	u8	num_caps;
+	u32	len;
+	struct hci_codec_caps caps[];
+};
+
 struct bdaddr_list_with_irk {
 	struct list_head list;
 	bdaddr_t bdaddr;
···
 	struct list_head	pend_le_conns;
 	struct list_head	pend_le_reports;
 	struct list_head	blocked_keys;
+	struct list_head	local_codecs;
 
 	struct hci_dev_stats	stat;
 
···
 #define SCO_AIRMODE_MASK       0x0003
 #define SCO_AIRMODE_CVSD       0x0000
 #define SCO_AIRMODE_TRANSP     0x0003
+
+#define LOCAL_CODEC_ACL_MASK	BIT(0)
+#define LOCAL_CODEC_SCO_MASK	BIT(1)
+
+#define TRANSPORT_TYPE_MAX	0x04
 
 #endif /* __HCI_CORE_H */

net/bluetooth/Makefile

···
 
 bluetooth-y := af_bluetooth.o hci_core.o hci_conn.o hci_event.o mgmt.o \
 	hci_sock.o hci_sysfs.o l2cap_core.o l2cap_sock.o smp.o lib.o \
-	ecdh_helper.o hci_request.o mgmt_util.o mgmt_config.o
+	ecdh_helper.o hci_request.o mgmt_util.o mgmt_config.o hci_codec.o
 
 bluetooth-$(CONFIG_BT_BREDR) += sco.o
 bluetooth-$(CONFIG_BT_HS) += a2mp.o amp.o

net/bluetooth/hci_codec.c

···
+// SPDX-License-Identifier: GPL-2.0
+
+/* Copyright (C) 2021 Intel Corporation */
+
+#include <net/bluetooth/bluetooth.h>
+#include <net/bluetooth/hci_core.h>
+#include "hci_codec.h"
+
+static int hci_codec_list_add(struct list_head *list,
+			      struct hci_op_read_local_codec_caps *sent,
+			      struct hci_rp_read_local_codec_caps *rp,
+			      void *caps,
+			      __u32 len)
+{
+	struct codec_list *entry;
+
+	entry = kzalloc(sizeof(*entry) + len, GFP_KERNEL);
+	if (!entry)
+		return -ENOMEM;
+
+	entry->id = sent->id;
+	if (sent->id == 0xFF) {
+		entry->cid = __le16_to_cpu(sent->cid);
+		entry->vid = __le16_to_cpu(sent->vid);
+	}
+	entry->transport = sent->transport;
+	entry->len = len;
+	entry->num_caps = rp->num_caps;
+	if (rp->num_caps)
+		memcpy(entry->caps, caps, len);
+	list_add(&entry->list, list);
+
+	return 0;
+}
+
+void hci_codec_list_clear(struct list_head *codec_list)
+{
+	struct codec_list *c, *n;
+
+	list_for_each_entry_safe(c, n, codec_list, list) {
+		list_del(&c->list);
+		kfree(c);
+	}
+}
+
+static void hci_read_codec_capabilities(struct hci_dev *hdev, __u8 transport,
+					struct hci_op_read_local_codec_caps
+					*cmd)
+{
+	__u8 i;
+
+	for (i = 0; i < TRANSPORT_TYPE_MAX; i++) {
+		if (transport & BIT(i)) {
+			struct hci_rp_read_local_codec_caps *rp;
+			struct hci_codec_caps *caps;
+			struct sk_buff *skb;
+			__u8 j;
+			__u32 len;
+
+			cmd->transport = i;
+			skb = __hci_cmd_sync(hdev, HCI_OP_READ_LOCAL_CODEC_CAPS,
+					     sizeof(*cmd), cmd,
+					     HCI_CMD_TIMEOUT);
+			if (IS_ERR(skb)) {
+				bt_dev_err(hdev, "Failed to read codec capabilities (%ld)",
+					   PTR_ERR(skb));
+				continue;
+			}
+
+			if (skb->len < sizeof(*rp))
+				goto error;
+
+			rp = (void *)skb->data;
+
+			if (rp->status)
+				goto error;
+
+			if (!rp->num_caps) {
+				len = 0;
+				/* this codec doesn't have capabilities */
+				goto skip_caps_parse;
+			}
+
+			skb_pull(skb, sizeof(*rp));
+
+			for (j = 0, len = 0; j < rp->num_caps; j++) {
+				caps = (void *)skb->data;
+				if (skb->len < sizeof(*caps))
+					goto error;
+				if (skb->len < caps->len)
+					goto error;
+				len += sizeof(caps->len) + caps->len;
+				skb_pull(skb,  sizeof(caps->len) + caps->len);
+			}
+
+skip_caps_parse:
+			hci_dev_lock(hdev);
+			hci_codec_list_add(&hdev->local_codecs, cmd, rp,
+					   (__u8 *)rp + sizeof(*rp), len);
+			hci_dev_unlock(hdev);
+error:
+			kfree_skb(skb);
+		}
+	}
+}
+
+void hci_read_supported_codecs(struct hci_dev *hdev)
+{
+	struct sk_buff *skb;
+	struct hci_rp_read_local_supported_codecs *rp;
+	struct hci_std_codecs *std_codecs;
+	struct hci_vnd_codecs *vnd_codecs;
+	struct hci_op_read_local_codec_caps caps;
+	__u8 i;
+
+	skb = __hci_cmd_sync(hdev, HCI_OP_READ_LOCAL_CODECS, 0, NULL,
+			     HCI_CMD_TIMEOUT);
+
+	if (IS_ERR(skb)) {
+		bt_dev_err(hdev, "Failed to read local supported codecs (%ld)",
+			   PTR_ERR(skb));
+		return;
+	}
+
+	if (skb->len < sizeof(*rp))
+		goto error;
+
+	rp = (void *)skb->data;
+
+	if (rp->status)
+		goto error;
+
+	skb_pull(skb, sizeof(rp->status));
+
+	std_codecs = (void *)skb->data;
+
+	/* validate codecs length before accessing */
+	if (skb->len < flex_array_size(std_codecs, codec, std_codecs->num)
+	    + sizeof(std_codecs->num))
+		goto error;
+
+	/* enumerate codec capabilities of standard codecs */
+	memset(&caps, 0, sizeof(caps));
+	for (i = 0; i < std_codecs->num; i++) {
+		caps.id = std_codecs->codec[i];
+		caps.direction = 0x00;
+		hci_read_codec_capabilities(hdev, LOCAL_CODEC_ACL_MASK, &caps);
+	}
+
+	skb_pull(skb, flex_array_size(std_codecs, codec, std_codecs->num)
+		 + sizeof(std_codecs->num));
+
+	vnd_codecs = (void *)skb->data;
+
+	/* validate vendor codecs length before accessing */
+	if (skb->len <
+	    flex_array_size(vnd_codecs, codec, vnd_codecs->num)
+	    + sizeof(vnd_codecs->num))
+		goto error;
+
+	/* enumerate vendor codec capabilities */
+	for (i = 0; i < vnd_codecs->num; i++) {
+		caps.id = 0xFF;
+		caps.cid = vnd_codecs->codec[i].cid;
+		caps.vid = vnd_codecs->codec[i].vid;
+		caps.direction = 0x00;
+		hci_read_codec_capabilities(hdev, LOCAL_CODEC_ACL_MASK, &caps);
+	}
+
+error:
+	kfree_skb(skb);
+}

net/bluetooth/hci_codec.h

···
+/* SPDX-License-Identifier: GPL-2.0 */
+
+/* Copyright (C) 2014 Intel Corporation */
+
+void hci_read_supported_codecs(struct hci_dev *hdev);
+void hci_codec_list_clear(struct list_head *codec_list);

net/bluetooth/hci_core.c

···
 #include "leds.h"
 #include "msft.h"
 #include "aosp.h"
+#include "hci_codec.h"
 
 static void hci_rx_work(struct work_struct *work);
 static void hci_cmd_work(struct work_struct *work);
···
 	if (hdev->commands[22] & 0x04)
 		hci_set_event_mask_page_2(req);
 
-	/* Read local codec list if the HCI command is supported */
-	if (hdev->commands[29] & 0x20)
-		hci_req_add(req, HCI_OP_READ_LOCAL_CODECS, 0, NULL);
-
 	/* Read local pairing options if the HCI command is supported */
 	if (hdev->commands[41] & 0x08)
 		hci_req_add(req, HCI_OP_READ_LOCAL_PAIRING_OPTS, 0, NULL);
···
 	err = __hci_req_sync(hdev, hci_init4_req, 0, HCI_INIT_TIMEOUT, NULL);
 	if (err < 0)
 		return err;
+
+	/* Read local codec list if the HCI command is supported */
+	if (hdev->commands[29] & 0x20)
+		hci_read_supported_codecs(hdev);
 
 	/* This function is only called when the controller is actually in
 	 * configured state. When the controller is marked as unconfigured,
···
 	memset(hdev->eir, 0, sizeof(hdev->eir));
 	memset(hdev->dev_class, 0, sizeof(hdev->dev_class));
 	bacpy(&hdev->random_addr, BDADDR_ANY);
+	hci_codec_list_clear(&hdev->local_codecs);
 
 	hci_req_sync_unlock(hdev);
 
···
 	INIT_LIST_HEAD(&hdev->adv_instances);
 	INIT_LIST_HEAD(&hdev->blocked_keys);
 
+	INIT_LIST_HEAD(&hdev->local_codecs);
 	INIT_WORK(&hdev->rx_work, hci_rx_work);
 	INIT_WORK(&hdev->cmd_work, hci_cmd_work);
 	INIT_WORK(&hdev->tx_work, hci_tx_work);