Re: [PATCH v11 04/10] Bluetooth: Allow querying of supported offload codecs over SCO socket

[Marcel Holtmann <marcel@holtmann.org>]

Hi Kiran,

> 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>
> ---
> * changes in v11:
>  - Remove Kconfig related changes
> * changes in v10:
>  - In getsockopt, prepare data in advance and call copy_to_user
>    istead of calling put_user on each field of struct bt_codec
> 
> include/net/bluetooth/bluetooth.h | 20 +++++++
> include/net/bluetooth/hci.h       |  4 ++
> include/net/bluetooth/hci_core.h  |  1 +
> net/bluetooth/sco.c               | 91 +++++++++++++++++++++++++++++++
> 4 files changed, 116 insertions(+)
> 
> diff --git a/include/net/bluetooth/bluetooth.h b/include/net/bluetooth/bluetooth.h
> index 9125effbf448..64cddff0c9c4 100644
> --- a/include/net/bluetooth/bluetooth.h
> +++ b/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)
> diff --git a/include/net/bluetooth/hci.h b/include/net/bluetooth/hci.h
> index b4e35cf5f4b1..22e872e60ff8 100644
> --- a/include/net/bluetooth/hci.h
> +++ b/include/net/bluetooth/hci.h
> @@ -2621,6 +2621,10 @@ 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 TRANSPORT_ACL		0x00
> +#define TRANSPORT_SCO_ESCO	0x01
> +
> /* le24 support */
> static inline void hci_cpu_to_le24(__u32 val, __u8 dst[3])
> {
> diff --git a/include/net/bluetooth/hci_core.h b/include/net/bluetooth/hci_core.h
> index 6742e6ad7b37..71c409c8ab34 100644
> --- a/include/net/bluetooth/hci_core.h
> +++ b/include/net/bluetooth/hci_core.h
> @@ -617,6 +617,7 @@ struct hci_dev {
> 	int (*set_bdaddr)(struct hci_dev *hdev, const bdaddr_t *bdaddr);
> 	void (*cmd_timeout)(struct hci_dev *hdev);
> 	bool (*prevent_wake)(struct hci_dev *hdev);
> +	int (*get_data_path_id)(struct hci_dev *hdev, __u8 *data_path);
> };
> 
> #define HCI_PHY_HANDLE(handle)	(handle & 0xff)
> diff --git a/net/bluetooth/sco.c b/net/bluetooth/sco.c
> index ffa2a77a3e4c..2f32693f09c1 100644
> --- a/net/bluetooth/sco.c
> +++ b/net/bluetooth/sco.c
> @@ -953,6 +953,12 @@ 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);
> 
> @@ -1017,6 +1023,91 @@ 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 (!hdev->get_data_path_id) {
> +			err = -EOPNOTSUPP;
> +			break;
> +		}

so I did say that this needs to be put behind an experimental feature setting. I am not committing to an userspace API until we have more feedback.

Regards

Marcel