Bluetooth: Add support for Shorter Connection Interval (SCI) feature

Add HCI command, event and feature bit definitions for the Bluetooth
6.2 Shorter Connection Interval feature:

Commands:
 - HCI_OP_LE_CONN_RATE (0x20a1) - Connection Rate Request
 - HCI_OP_LE_SET_DEF_RATE (0x20a2) - Set Default Rate Parameters
 - HCI_OP_LE_READ_CONN_INTERVAL (0x20a3) - Read Min Supported
   Connection Interval

Events:
 - HCI_EVT_LE_CONN_RATE_CHANGE (0x37) - Connection Rate Change

Feature bits:
 - HCI_LE_SCI - Shorter Connection Intervals
 - HCI_LE_SCI_HOST - Shorter Connection Intervals (Host Support)

During controller init, when SCI is supported:
 - Set Shorter Connection Intervals (Host Support) feature via
   LE Set Host Feature
 - Read Minimum Supported Connection Interval
 - Set Default Rate Parameters

The Connection Rate Change event handler updates the connection
interval, latency and supervision timeout on the hci_conn.

Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>

2 files changed, 62 insertions, 0 deletions

diff --git a/include/net/bluetooth/hci.h b/include/net/bluetooth/hci.h
index d557bdf9ae57..cd3520a29131 100644
--- a/include/net/bluetooth/hci.h
+++ b/include/net/bluetooth/hci.h
@@ -653,6 +653,8 @@ enum {
 #define HCI_LE_LL_EXT_FEATURE		0x80
 #define HCI_LE_CS			0x40
 #define HCI_LE_CS_HOST			0x80
+#define HCI_LE_SCI			0x01	/* byte 9 - Shorter Connection Intervals */
+#define HCI_LE_SCI_HOST			0x02	/* byte 9 - Shorter Connection Intervals (Host) */
 
 /* Connection modes */
 #define HCI_CM_ACTIVE	0x0000
@@ -2489,6 +2491,46 @@ struct hci_cp_le_set_host_feature_v2 {
 	__u8	bit_value;
 } __packed;
 
+#define HCI_OP_LE_CONN_RATE			0x20a1
+struct hci_cp_le_conn_rate {
+	__le16	handle;
+	__le16	interval_min;
+	__le16	interval_max;
+	__le16	subrate_min;
+	__le16	subrate_max;
+	__le16	max_latency;
+	__le16	cont_num;
+	__le16	supv_timeout;
+	__le16	min_ce_len;
+	__le16	max_ce_len;
+} __packed;
+
+#define HCI_OP_LE_SET_DEF_RATE			0x20a2
+struct hci_cp_le_set_def_rate {
+	__le16	interval_min;
+	__le16	interval_max;
+	__le16	subrate_min;
+	__le16	subrate_max;
+	__le16	max_latency;
+	__le16	cont_num;
+	__le16	supv_timeout;
+	__le16	min_ce_len;
+	__le16	max_ce_len;
+} __packed;
+
+#define HCI_OP_LE_READ_CONN_INTERVAL		0x20a3
+struct hci_le_conn_interval_group {
+	__le16	min;
+	__le16	max;
+	__le16	stride;
+} __packed;
+
+struct hci_rp_le_read_conn_interval {
+	__u8	status;
+	__u8	num_grps;
+	struct hci_le_conn_interval_group grps[];
+} __packed;
+
 /* ---- HCI Events ---- */
 struct hci_ev_status {
 	__u8    status;
@@ -3303,6 +3345,17 @@ struct hci_evt_le_cs_test_end_complete {
 	__u8	status;
 } __packed;
 
+#define HCI_EVT_LE_CONN_RATE_CHANGE			0x37
+struct hci_evt_le_conn_rate_change {
+	__u8	status;
+	__le16	handle;
+	__le16	interval;
+	__le16	subrate;
+	__le16	latency;
+	__le16	cont_number;
+	__le16	supv_timeout;
+} __packed;
+
 #define HCI_EV_VENDOR			0xff
 
 /* Internal events generated by Bluetooth stack */
diff --git a/include/net/bluetooth/hci_core.h b/include/net/bluetooth/hci_core.h
index 3df59849dcbe..f48f875022d4 100644
--- a/include/net/bluetooth/hci_core.h
+++ b/include/net/bluetooth/hci_core.h
@@ -416,6 +416,7 @@ struct hci_dev {
 	__u16		le_conn_max_interval;
 	__u16		le_conn_latency;
 	__u16		le_supv_timeout;
+	__u16		le_min_rate_interval;
 	__u16		le_def_tx_len;
 	__u16		le_def_tx_time;
 	__u16		le_max_tx_len;
@@ -720,6 +721,11 @@ struct hci_conn {
 	__u16		le_conn_interval;
 	__u16		le_conn_latency;
 	__u16		le_supv_timeout;
+	__u16		le_rate_interval;
+	__u16		le_subrate;
+	__u16		le_rate_latency;
+	__u16		le_cont_num;
+	__u16		le_rate_supv_timeout;
 	__u8		le_adv_data[HCI_MAX_EXT_AD_LENGTH];
 	__u8		le_adv_data_len;
 	__u8		le_per_adv_data[HCI_MAX_PER_AD_TOT_LEN];
@@ -2079,6 +2085,9 @@ void hci_conn_del_sysfs(struct hci_conn *conn);
 #define le_cs_host_capable(dev) \
 	((dev)->le_features[5] & HCI_LE_CS_HOST)
 
+#define le_sci_capable(dev) \
+	((dev)->le_features[9] & HCI_LE_SCI)
+
 #define mws_transport_config_capable(dev) (((dev)->commands[30] & 0x08) && \
 	(!hci_test_quirk((dev), HCI_QUIRK_BROKEN_MWS_TRANSPORT_CONFIG)))