RE: [PATCH v11 10/10] Bluetooth: Add offload feature under experimental flag

Hi Marcel,

-----Original Message-----
From: Marcel Holtmann <marcel@holtmann.org>
Sent: Friday, July 30, 2021 7:52 PM
To: K, Kiran <redacted>
Cc: linux-bluetooth@vger.kernel.org; Srivatsa, Ravishankar
[off-list ref]; Tumkur Narayan, Chethan
[off-list ref]
Subject: Re: [PATCH v11 10/10] Bluetooth: Add offload feature under
experimental flag

Hi Kiran,

quoted

Allow user level process to enable / disable codec offload feature
through mgmt interface. By default offload codec feature is disabled.

Signed-off-by: Kiran K <redacted>
Reviewed-by: Chethan T N <redacted>
Reviewed-by: Srivatsa Ravishankar <redacted>
---
changes in v11:
- Remove Kconfig

include/net/bluetooth/hci.h |  1 +
net/bluetooth/mgmt.c        | 98

++++++++++++++++++++++++++++++++++++-

quoted

net/bluetooth/sco.c         | 10 ++++
3 files changed, 108 insertions(+), 1 deletion(-)

diff --git a/include/net/bluetooth/hci.h b/include/net/bluetooth/hci.h
index 8af8892e18bc..dbbbb974ade6 100644
--- a/include/net/bluetooth/hci.h
+++ b/include/net/bluetooth/hci.h

@@ -330,6 +330,7 @@ enum {

	HCI_ENABLE_LL_PRIVACY,
	HCI_CMD_PENDING,
	HCI_FORCE_NO_MITM,
+	HCI_OFFLOAD_CODECS_ENABLED,

	__HCI_NUM_FLAGS,
};

diff --git a/net/bluetooth/mgmt.c b/net/bluetooth/mgmt.c index

3663f880df11..eb10f9597837 100644

--- a/net/bluetooth/mgmt.c
+++ b/net/bluetooth/mgmt.c

@@ -3791,6 +3791,12 @@ static const u8 debug_uuid[16] = { }; #endif

+/* a6695ace-ee7f-4fb9-881a-5fac66c629af */ static const u8
+offload_codecs_uuid[16] = {
+	0xaf, 0x29, 0xc6, 0x66, 0xac, 0x5f, 0x1a, 0x88,
+	0xb9, 0x4f, 0x7f, 0xee, 0xce, 0x5a, 0x69, 0xa6, };
+

/* 671b10b5-42c0-4696-9227-eb28d1b049d6 */ static const u8
simult_central_periph_uuid[16] = {
	0xd6, 0x49, 0xb0, 0xd1, 0x28, 0xeb, 0x27, 0x92, @@ -3806,7 +3812,7

@@

quoted

static const u8 rpa_resolution_uuid[16] = { static int
read_exp_features_info(struct sock *sk, struct hci_dev *hdev,
				  void *data, u16 data_len)
{
-	char buf[62];	/* Enough space for 3 features */
+	char buf[82];   /* Enough space for 4 features: 2 + 20 * 4 */
	struct mgmt_rp_read_exp_features_info *rp = (void *)buf;
	u16 idx = 0;
	u32 flags;

@@ -3850,6 +3856,26 @@ static int read_exp_features_info(struct sock

*sk, struct hci_dev *hdev,

quoted

		idx++;
	}

+	if (hdev) {
+		if (hdev->get_data_path_id) {
+			/* BIT(0): indicating if offload codecs are
+			 * supported by controller.
+			 */
+			flags = BIT(0);
+
+			/* BIT(1): indicating if codec offload feature
+			 * is enabled.
+			 */
+			if (hci_dev_test_flag(hdev,

HCI_OFFLOAD_CODECS_ENABLED))

quoted

+				flags |= BIT(1);
+		} else {
+			flags = 0;
+		}
+		memcpy(rp->features[idx].uuid, offload_codecs_uuid, 16);
+		rp->features[idx].flags = cpu_to_le32(flags);
+		idx++;
+	}
+
	rp->feature_count = cpu_to_le16(idx);

	/* After reading the experimental features information, enable @@
-3892,6 +3918,21 @@ static int exp_debug_feature_changed(bool enabled,
struct sock *skip) } #endif

+static int exp_offload_codec_feature_changed(bool enabled, struct
+sock *skip) {
+	struct mgmt_ev_exp_feature_changed ev;
+
+	BT_INFO("enabled %d", enabled);
+
+	memset(&ev, 0, sizeof(ev));
+	memcpy(ev.uuid, offload_codecs_uuid, 16);
+	ev.flags = cpu_to_le32(enabled ? BIT(0) : 0);
+
+	return mgmt_limited_event(MGMT_EV_EXP_FEATURE_CHANGED,

NULL,

quoted

+				  &ev, sizeof(ev),
+				  HCI_MGMT_EXP_FEATURE_EVENTS, skip); }
+
static int set_exp_feature(struct sock *sk, struct hci_dev *hdev,
			   void *data, u16 data_len)
{

@@ -4038,6 +4079,61 @@ static int set_exp_feature(struct sock *sk, struct

hci_dev *hdev,

quoted

		return err;
	}

+	if (!memcmp(cp->uuid, offload_codecs_uuid, 16)) {
+		bool val, changed;
+		int err;
+
+		/* Command requires to use a valid controller index */
+		if (!hdev)
+			return mgmt_cmd_status(sk, MGMT_INDEX_NONE,
+					       MGMT_OP_SET_EXP_FEATURE,
+					       MGMT_STATUS_INVALID_INDEX);
+
+		/* Parameters are limited to a single octet */
+		if (data_len != MGMT_SET_EXP_FEATURE_SIZE + 1)
+			return mgmt_cmd_status(sk, hdev->id,
+					       MGMT_OP_SET_EXP_FEATURE,
+

MGMT_STATUS_INVALID_PARAMS);

quoted

+
+		/* Only boolean on/off is supported */
+		if (cp->param[0] != 0x00 && cp->param[0] != 0x01)
+			return mgmt_cmd_status(sk, hdev->id,
+					       MGMT_OP_SET_EXP_FEATURE,
+

MGMT_STATUS_INVALID_PARAMS);

quoted

+
+		val = !!cp->param[0];
+		changed = (val != hci_dev_test_flag(hdev,
+HCI_OFFLOAD_CODECS_ENABLED));
+
+		if (!hdev->get_data_path_id) {
+			bt_dev_info(hdev, "offload codecs not supported");
+			return mgmt_cmd_status(sk, hdev->id,
+					       MGMT_OP_SET_EXP_FEATURE,
+

MGMT_STATUS_NOT_SUPPORTED);

quoted

+		}
+
+		if (changed) {
+			if (val)
+				hci_dev_set_flag(hdev,

HCI_OFFLOAD_CODECS_ENABLED);

quoted

+			else
+				hci_dev_clear_flag(hdev,

HCI_OFFLOAD_CODECS_ENABLED);

quoted

+		}
+
+		bt_dev_info(hdev, "offload codecs enable %d changed %d",
+			    val, changed);
+
+		memcpy(rp.uuid, offload_codecs_uuid, 16);
+		rp.flags = cpu_to_le32(val ? BIT(0) : 0);
+		hci_sock_set_flag(sk, HCI_MGMT_EXP_FEATURE_EVENTS);
+		err = mgmt_cmd_complete(sk, hdev->id,
+					MGMT_OP_SET_EXP_FEATURE, 0,
+					&rp, sizeof(rp));
+
+		if (changed)
+			exp_offload_codec_feature_changed(val, sk);
+
+		return err;
+	}
+
	return mgmt_cmd_status(sk, hdev ? hdev->id : MGMT_INDEX_NONE,
			       MGMT_OP_SET_EXP_FEATURE,
			       MGMT_STATUS_NOT_SUPPORTED);

diff --git a/net/bluetooth/sco.c b/net/bluetooth/sco.c index

5ff06ac05fef..ba66e082ba9e 100644

--- a/net/bluetooth/sco.c
+++ b/net/bluetooth/sco.c

@@ -964,6 +964,11 @@ static int sco_sock_setsockopt(struct socket *sock,

int level, int optname,

quoted

			break;
		}

+		if (!hci_dev_test_flag(hdev,

HCI_OFFLOAD_CODECS_ENABLED)) {

quoted

+			err = -EOPNOTSUPP;
+			break;
+		}
+
		if (!hdev->get_codec_config_data) {
			err = -EOPNOTSUPP;
			break;

@@ -1160,6 +1165,11 @@ static int sco_sock_getsockopt(struct socket

*sock, int level, int optname,

quoted

			break;
		}

+		if (!hci_dev_test_flag(hdev,

HCI_OFFLOAD_CODECS_ENABLED)) {

quoted

+			err = -EOPNOTSUPP;
+			break;
+		}
+
		if (!hdev->get_data_path_id) {
			err = -EOPNOTSUPP;
			break;

these two and the flag definition itself need to be a lot earlier in the series.

Ack.

Regards

Marcel

Thanks,
Kiran