diff mbox series

[v1,1/2] Bluetooth: hci_core: Enable buffer flow control for SCO/eSCO

Message ID 20250311195528.41993-1-luiz.dentz@gmail.com (mailing list archive)
State Superseded
Headers show
Series [v1,1/2] Bluetooth: hci_core: Enable buffer flow control for SCO/eSCO | expand

Checks

Context Check Description
tedd_an/pre-ci_am success Success
tedd_an/SubjectPrefix success Gitlint PASS
tedd_an/BuildKernel success BuildKernel PASS
tedd_an/CheckAllWarning success CheckAllWarning PASS
tedd_an/CheckSparse warning CheckSparse WARNING net/bluetooth/hci_event.c: note: in included file (through include/net/bluetooth/hci_core.h):
tedd_an/BuildKernel32 success BuildKernel32 PASS
tedd_an/TestRunnerSetup success TestRunnerSetup PASS
tedd_an/TestRunner_l2cap-tester success TestRunner PASS
tedd_an/TestRunner_iso-tester success TestRunner PASS
tedd_an/TestRunner_bnep-tester success TestRunner PASS
tedd_an/TestRunner_mgmt-tester fail TestRunner_mgmt-tester: Total: 490, Passed: 485 (99.0%), Failed: 1, Not Run: 4
tedd_an/TestRunner_rfcomm-tester success TestRunner PASS
tedd_an/TestRunner_sco-tester fail TestRunner_sco-tester: Total: 19, Passed: 17 (89.5%), Failed: 1, Not Run: 1
tedd_an/TestRunner_ioctl-tester success TestRunner PASS
tedd_an/TestRunner_mesh-tester success TestRunner PASS
tedd_an/TestRunner_smp-tester success TestRunner PASS
tedd_an/TestRunner_userchan-tester success TestRunner PASS

Commit Message

Luiz Augusto von Dentz March 11, 2025, 7:55 p.m. UTC
From: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>

This enables buffer flow control for SCO/eSCO
(see: Bluetooth Core 6.0 spec: 6.22. Synchronous Flow Control Enable),
recently this has caused the following problem and is actually a nice
addition for the likes of Socket TX complete:

< HCI Command: Read Buffer Size (0x04|0x0005) plen 0
> HCI Event: Command Complete (0x0e) plen 11
      Read Buffer Size (0x04|0x0005) ncmd 1
        Status: Success (0x00)
        ACL MTU: 1021 ACL max packet: 5
        SCO MTU: 240  SCO max packet: 8
...
< SCO Data TX: Handle 257 flags 0x00 dlen 120
< SCO Data TX: Handle 257 flags 0x00 dlen 120
< SCO Data TX: Handle 257 flags 0x00 dlen 120
< SCO Data TX: Handle 257 flags 0x00 dlen 120
< SCO Data TX: Handle 257 flags 0x00 dlen 120
< SCO Data TX: Handle 257 flags 0x00 dlen 120
< SCO Data TX: Handle 257 flags 0x00 dlen 120
< SCO Data TX: Handle 257 flags 0x00 dlen 120
< SCO Data TX: Handle 257 flags 0x00 dlen 120
> HCI Event: Hardware Error (0x10) plen 1
        Code: 0x0a

To fix the code will now attempt to enable buffer flow control:

< HCI Command: Write Sync Fl.. (0x03|0x002f) plen 1
        Flow control: Enabled (0x01)
> HCI Event: Command Complete (0x0e) plen 4
      Write Sync Flow Control Enable (0x03|0x002f) ncmd 1
        Status: Success (0x00)

And then test it by sending an empty packet to confirm the controller
will generate HCI_EV_NUM_COMP_PKTS events:

sco-tester[40]: < SCO Data TX:.. flags 0x00 dlen 9
> HCI Event: Number of Completed P.. (0x13) plen 5
        Num handles: 1
        Handle: 42 Address: 00:AA:01:01:00:00 (Intel Corporation)
        Count: 1
        #103: len 10 (40 Kb/s)
        Latency: 2 msec (2-2 msec ~2 msec)

Fixes: 7fedd3bb6b77 ("Bluetooth: Prioritize SCO traffic")
Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>
---
 include/net/bluetooth/hci.h      | 13 +++++++
 include/net/bluetooth/hci_core.h |  1 +
 net/bluetooth/hci_core.c         | 67 ++++++++++++++++----------------
 net/bluetooth/hci_event.c        |  2 +
 net/bluetooth/hci_sync.c         | 24 ++++++++++++
 5 files changed, 74 insertions(+), 33 deletions(-)

Comments

bluez.test.bot@gmail.com March 11, 2025, 8:34 p.m. UTC | #1
This is automated email and please do not reply to this email!

Dear submitter,

Thank you for submitting the patches to the linux bluetooth mailing list.
This is a CI test results with your patch series:
PW Link:https://patchwork.kernel.org/project/bluetooth/list/?series=942852

---Test result---

Test Summary:
CheckPatch                    PENDING   0.32 seconds
GitLint                       PENDING   0.19 seconds
SubjectPrefix                 PASS      0.19 seconds
BuildKernel                   PASS      24.38 seconds
CheckAllWarning               PASS      26.74 seconds
CheckSparse                   WARNING   32.92 seconds
BuildKernel32                 PASS      24.00 seconds
TestRunnerSetup               PASS      437.90 seconds
TestRunner_l2cap-tester       PASS      21.71 seconds
TestRunner_iso-tester         PASS      37.67 seconds
TestRunner_bnep-tester        PASS      4.93 seconds
TestRunner_mgmt-tester        FAIL      123.93 seconds
TestRunner_rfcomm-tester      PASS      8.14 seconds
TestRunner_sco-tester         FAIL      19.11 seconds
TestRunner_ioctl-tester       PASS      8.70 seconds
TestRunner_mesh-tester        PASS      6.17 seconds
TestRunner_smp-tester         PASS      7.45 seconds
TestRunner_userchan-tester    PASS      5.09 seconds
IncrementalBuild              PENDING   0.72 seconds

Details
##############################
Test: CheckPatch - PENDING
Desc: Run checkpatch.pl script
Output:

##############################
Test: GitLint - PENDING
Desc: Run gitlint
Output:

##############################
Test: CheckSparse - WARNING
Desc: Run sparse tool with linux kernel
Output:
net/bluetooth/hci_event.c: note: in included file (through include/net/bluetooth/hci_core.h):
##############################
Test: TestRunner_mgmt-tester - FAIL
Desc: Run mgmt-tester with test-runner
Output:
Total: 490, Passed: 485 (99.0%), Failed: 1, Not Run: 4

Failed Test Cases
LL Privacy - Start Discovery 2 (Disable RL)          Failed       0.199 seconds
##############################
Test: TestRunner_sco-tester - FAIL
Desc: Run sco-tester with test-runner
Output:
Total: 19, Passed: 17 (89.5%), Failed: 1, Not Run: 1

Failed Test Cases
SCO CVSD Send - Success                              Timed out    2.547 seconds
##############################
Test: IncrementalBuild - PENDING
Desc: Incremental build with the patches in the series
Output:



---
Regards,
Linux Bluetooth
Pauli Virtanen March 11, 2025, 10:21 p.m. UTC | #2
Hi,

ti, 2025-03-11 kello 15:55 -0400, Luiz Augusto von Dentz kirjoitti:
> From: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>
> 
> This enables buffer flow control for SCO/eSCO
> (see: Bluetooth Core 6.0 spec: 6.22. Synchronous Flow Control Enable),
> recently this has caused the following problem and is actually a nice
> addition for the likes of Socket TX complete:
> 
> < HCI Command: Read Buffer Size (0x04|0x0005) plen 0
> > HCI Event: Command Complete (0x0e) plen 11
>       Read Buffer Size (0x04|0x0005) ncmd 1
>         Status: Success (0x00)
>         ACL MTU: 1021 ACL max packet: 5
>         SCO MTU: 240  SCO max packet: 8
> ...
> < SCO Data TX: Handle 257 flags 0x00 dlen 120
> < SCO Data TX: Handle 257 flags 0x00 dlen 120
> < SCO Data TX: Handle 257 flags 0x00 dlen 120
> < SCO Data TX: Handle 257 flags 0x00 dlen 120
> < SCO Data TX: Handle 257 flags 0x00 dlen 120
> < SCO Data TX: Handle 257 flags 0x00 dlen 120
> < SCO Data TX: Handle 257 flags 0x00 dlen 120
> < SCO Data TX: Handle 257 flags 0x00 dlen 120
> < SCO Data TX: Handle 257 flags 0x00 dlen 120
> > HCI Event: Hardware Error (0x10) plen 1
>         Code: 0x0a
> 
> To fix the code will now attempt to enable buffer flow control:
> 
> < HCI Command: Write Sync Fl.. (0x03|0x002f) plen 1
>         Flow control: Enabled (0x01)
> > HCI Event: Command Complete (0x0e) plen 4
>       Write Sync Flow Control Enable (0x03|0x002f) ncmd 1
>         Status: Success (0x00)
> 
> And then test it by sending an empty packet to confirm the controller
> will generate HCI_EV_NUM_COMP_PKTS events:

It's not doing this any more in this version.

> 
> sco-tester[40]: < SCO Data TX:.. flags 0x00 dlen 9
> > HCI Event: Number of Completed P.. (0x13) plen 5
>         Num handles: 1
>         Handle: 42 Address: 00:AA:01:01:00:00 (Intel Corporation)
>         Count: 1
>         #103: len 10 (40 Kb/s)
>         Latency: 2 msec (2-2 msec ~2 msec)
> 
> Fixes: 7fedd3bb6b77 ("Bluetooth: Prioritize SCO traffic")
> Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>
> ---
>  include/net/bluetooth/hci.h      | 13 +++++++
>  include/net/bluetooth/hci_core.h |  1 +
>  net/bluetooth/hci_core.c         | 67 ++++++++++++++++----------------
>  net/bluetooth/hci_event.c        |  2 +
>  net/bluetooth/hci_sync.c         | 24 ++++++++++++
>  5 files changed, 74 insertions(+), 33 deletions(-)
> 
> diff --git a/include/net/bluetooth/hci.h b/include/net/bluetooth/hci.h
> index b99818df8ee7..3c8f95174fcf 100644
> --- a/include/net/bluetooth/hci.h
> +++ b/include/net/bluetooth/hci.h
> @@ -208,6 +208,13 @@ enum {
>  	 */
>  	HCI_QUIRK_WIDEBAND_SPEECH_SUPPORTED,
>  
> +	/* When this quirk is set consider Sync Flow Control as supported by
> +	 * the driver.
> +	 *
> +	 * This quirk must be set before hci_register_dev is called.
> +	 */
> +	HCI_QUIRK_SYNC_FLOWCTL_SUPPORTED,
> +
>  	/* When this quirk is set, the LE states reported through the
>  	 * HCI_LE_READ_SUPPORTED_STATES are invalid/broken.
>  	 *
> @@ -448,6 +455,7 @@ enum {
>  	HCI_WIDEBAND_SPEECH_ENABLED,
>  	HCI_EVENT_FILTER_CONFIGURED,
>  	HCI_PA_SYNC,
> +	HCI_SCO_FLOWCTL,
>  
>  	HCI_DUT_MODE,
>  	HCI_VENDOR_DIAG,
> @@ -1544,6 +1552,11 @@ struct hci_rp_read_tx_power {
>  	__s8     tx_power;
>  } __packed;
>  
> +#define HCI_OP_WRITE_SYNC_FLOWCTL	0x0c2f
> +struct hci_cp_write_sync_flowctl {
> +	__u8     enable;
> +} __packed;
> +
>  #define HCI_OP_READ_PAGE_SCAN_TYPE	0x0c46
>  struct hci_rp_read_page_scan_type {
>  	__u8     status;
> diff --git a/include/net/bluetooth/hci_core.h b/include/net/bluetooth/hci_core.h
> index 7966db4038cc..f78e4298e39a 100644
> --- a/include/net/bluetooth/hci_core.h
> +++ b/include/net/bluetooth/hci_core.h
> @@ -1858,6 +1858,7 @@ void hci_conn_del_sysfs(struct hci_conn *conn);
>  #define lmp_hold_capable(dev)      ((dev)->features[0][0] & LMP_HOLD)
>  #define lmp_sniff_capable(dev)     ((dev)->features[0][0] & LMP_SNIFF)
>  #define lmp_park_capable(dev)      ((dev)->features[0][1] & LMP_PARK)
> +#define lmp_sco_capable(dev)       ((dev)->features[0][1] & LMP_SCO)
>  #define lmp_inq_rssi_capable(dev)  ((dev)->features[0][3] & LMP_RSSI_INQ)
>  #define lmp_esco_capable(dev)      ((dev)->features[0][3] & LMP_ESCO)
>  #define lmp_bredr_capable(dev)     (!((dev)->features[0][4] & LMP_NO_BREDR))
> diff --git a/net/bluetooth/hci_core.c b/net/bluetooth/hci_core.c
> index 012fc107901a..efba2b539902 100644
> --- a/net/bluetooth/hci_core.c
> +++ b/net/bluetooth/hci_core.c
> @@ -3552,51 +3552,52 @@ static void __check_timeout(struct hci_dev *hdev, unsigned int cnt, u8 type)
>  }
>  
>  /* Schedule SCO */
> -static void hci_sched_sco(struct hci_dev *hdev)
> +static void hci_sched_sco_type(struct hci_dev *hdev, __u8 type)
>  {
>  	struct hci_conn *conn;
>  	struct sk_buff *skb;
>  	int quote;
> +	unsigned int pkts;
>  
> -	BT_DBG("%s", hdev->name);
> +	bt_dev_dbg(hdev, "type %u", type);
>  
> -	if (!hci_conn_num(hdev, SCO_LINK))
> +	if (!hci_conn_num(hdev, type))
>  		return;
>  
> -	while (hdev->sco_cnt && (conn = hci_low_sent(hdev, SCO_LINK, &quote))) {
> +	/* Use sco_pkts if flow control has not been enabled yet which will
> +	 * limit the amount of buffer sent in a row.
> +	 */
> +	if (!hci_dev_test_flag(hdev, HCI_SCO_FLOWCTL))
> +		pkts = hdev->sco_pkts;
> +	else
> +		pkts = hdev->sco_cnt;
> +
> +	if (!pkts)
> +		return;
> +
> +	while (pkts && (conn = hci_low_sent(hdev, type, &quote))) {
>  		while (quote-- && (skb = skb_dequeue(&conn->data_q))) {

hci_low_sent -> hci_quote_sent uses the current value of hdev->sco_cnt
to determine `quote`, which can then be larger than pkts, possibly
causing it to underflow here.

I guess this is why the other sched() functions are doing the (*cnt)--
thing.

>  			BT_DBG("skb %p len %d", skb, skb->len);
>  			hci_send_frame(hdev, skb);
>  
> +			pkts--;
> +
> +			if (hdev->sco_cnt > 0)
> +				hdev->sco_cnt--;
> +
>  			conn->sent++;
>  			if (conn->sent == ~0)
>  				conn->sent = 0;
>  		}
>  	}
> -}
>  
> -static void hci_sched_esco(struct hci_dev *hdev)
> -{
> -	struct hci_conn *conn;
> -	struct sk_buff *skb;
> -	int quote;
> -
> -	BT_DBG("%s", hdev->name);
> -
> -	if (!hci_conn_num(hdev, ESCO_LINK))
> -		return;
> -
> -	while (hdev->sco_cnt && (conn = hci_low_sent(hdev, ESCO_LINK,
> -						     &quote))) {
> -		while (quote-- && (skb = skb_dequeue(&conn->data_q))) {
> -			BT_DBG("skb %p len %d", skb, skb->len);
> -			hci_send_frame(hdev, skb);
> -
> -			conn->sent++;
> -			if (conn->sent == ~0)
> -				conn->sent = 0;
> -		}
> -	}
> +	/* Rescheduled if all packets were sent and flow control is not enabled
> +	 * as there could be more packets queued that could not be sent and
> +	 * since no HCI_EV_NUM_COMP_PKTS event will be generated the reschedule
> +	 * needs to be forced.
> +	 */
> +	if (!pkts && !hci_dev_test_flag(hdev, HCI_SCO_FLOWCTL))
> +		queue_work(hdev->workqueue, &hdev->tx_work);
>  }
>  
>  static void hci_sched_acl_pkt(struct hci_dev *hdev)
> @@ -3632,8 +3633,8 @@ static void hci_sched_acl_pkt(struct hci_dev *hdev)
>  			chan->conn->sent++;
>  
>  			/* Send pending SCO packets right away */
> -			hci_sched_sco(hdev);
> -			hci_sched_esco(hdev);
> +			hci_sched_sco_type(hdev, SCO_LINK);
> +			hci_sched_sco_type(hdev, ESCO_LINK);
>  		}
>  	}
>  
> @@ -3688,8 +3689,8 @@ static void hci_sched_le(struct hci_dev *hdev)
>  			chan->conn->sent++;
>  
>  			/* Send pending SCO packets right away */
> -			hci_sched_sco(hdev);
> -			hci_sched_esco(hdev);
> +			hci_sched_sco_type(hdev, SCO_LINK);
> +			hci_sched_sco_type(hdev, ESCO_LINK);
>  		}
>  	}
>  
> @@ -3734,8 +3735,8 @@ static void hci_tx_work(struct work_struct *work)
>  
>  	if (!hci_dev_test_flag(hdev, HCI_USER_CHANNEL)) {
>  		/* Schedule queues and send stuff to HCI driver */
> -		hci_sched_sco(hdev);
> -		hci_sched_esco(hdev);
> +		hci_sched_sco_type(hdev, SCO_LINK);
> +		hci_sched_sco_type(hdev, ESCO_LINK);
>  		hci_sched_iso(hdev);
>  		hci_sched_acl(hdev);
>  		hci_sched_le(hdev);
> diff --git a/net/bluetooth/hci_event.c b/net/bluetooth/hci_event.c
> index 19e19c9f5e68..6d0138b778aa 100644
> --- a/net/bluetooth/hci_event.c
> +++ b/net/bluetooth/hci_event.c
> @@ -4445,9 +4445,11 @@ static void hci_num_comp_pkts_evt(struct hci_dev *hdev, void *data,
>  			break;
>  
>  		case SCO_LINK:
> +		case ESCO_LINK:
>  			hdev->sco_cnt += count;
>  			if (hdev->sco_cnt > hdev->sco_pkts)
>  				hdev->sco_cnt = hdev->sco_pkts;
> +
>  			break;
>  
>  		case ISO_LINK:
> diff --git a/net/bluetooth/hci_sync.c b/net/bluetooth/hci_sync.c
> index c4c2cf51b219..609b035e5c90 100644
> --- a/net/bluetooth/hci_sync.c
> +++ b/net/bluetooth/hci_sync.c
> @@ -3769,6 +3769,28 @@ static int hci_write_ca_timeout_sync(struct hci_dev *hdev)
>  				     sizeof(param), &param, HCI_CMD_TIMEOUT);
>  }
>  
> +/* Enable SCO flow control if supported */
> +static int hci_write_sync_flowctl_sync(struct hci_dev *hdev)
> +{
> +	struct hci_cp_write_sync_flowctl cp;
> +	int err;
> +
> +	/* Check if the controller supports SCO and HCI_OP_WRITE_SYNC_FLOWCTL */
> +	if (!lmp_sco_capable(hdev) || !(hdev->commands[10] & BIT(4)) ||
> +	    !test_bit(HCI_QUIRK_SYNC_FLOWCTL_SUPPORTED, &hdev->quirks))
> +		return 0;
> +
> +	memset(&cp, 0, sizeof(cp));
> +	cp.enable = 0x01;
> +
> +	err = __hci_cmd_sync_status(hdev, HCI_OP_WRITE_SYNC_FLOWCTL,
> +				    sizeof(cp), &cp, HCI_CMD_TIMEOUT);
> +	if (!err)
> +		hci_dev_set_flag(hdev, HCI_SCO_FLOWCTL);
> +
> +	return err;
> +}
> +
>  /* BR Controller init stage 2 command sequence */
>  static const struct hci_init_stage br_init2[] = {
>  	/* HCI_OP_READ_BUFFER_SIZE */
> @@ -3787,6 +3809,8 @@ static const struct hci_init_stage br_init2[] = {
>  	HCI_INIT(hci_clear_event_filter_sync),
>  	/* HCI_OP_WRITE_CA_TIMEOUT */
>  	HCI_INIT(hci_write_ca_timeout_sync),
> +	/* HCI_OP_WRITE_SYNC_FLOWCTL */
> +	HCI_INIT(hci_write_sync_flowctl_sync),
>  	{}
>  };
>
Luiz Augusto von Dentz March 11, 2025, 10:38 p.m. UTC | #3
Hi Pauli,

On Tue, Mar 11, 2025 at 6:21 PM Pauli Virtanen <pav@iki.fi> wrote:
>
> Hi,
>
> ti, 2025-03-11 kello 15:55 -0400, Luiz Augusto von Dentz kirjoitti:
> > From: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>
> >
> > This enables buffer flow control for SCO/eSCO
> > (see: Bluetooth Core 6.0 spec: 6.22. Synchronous Flow Control Enable),
> > recently this has caused the following problem and is actually a nice
> > addition for the likes of Socket TX complete:
> >
> > < HCI Command: Read Buffer Size (0x04|0x0005) plen 0
> > > HCI Event: Command Complete (0x0e) plen 11
> >       Read Buffer Size (0x04|0x0005) ncmd 1
> >         Status: Success (0x00)
> >         ACL MTU: 1021 ACL max packet: 5
> >         SCO MTU: 240  SCO max packet: 8
> > ...
> > < SCO Data TX: Handle 257 flags 0x00 dlen 120
> > < SCO Data TX: Handle 257 flags 0x00 dlen 120
> > < SCO Data TX: Handle 257 flags 0x00 dlen 120
> > < SCO Data TX: Handle 257 flags 0x00 dlen 120
> > < SCO Data TX: Handle 257 flags 0x00 dlen 120
> > < SCO Data TX: Handle 257 flags 0x00 dlen 120
> > < SCO Data TX: Handle 257 flags 0x00 dlen 120
> > < SCO Data TX: Handle 257 flags 0x00 dlen 120
> > < SCO Data TX: Handle 257 flags 0x00 dlen 120
> > > HCI Event: Hardware Error (0x10) plen 1
> >         Code: 0x0a
> >
> > To fix the code will now attempt to enable buffer flow control:
> >
> > < HCI Command: Write Sync Fl.. (0x03|0x002f) plen 1
> >         Flow control: Enabled (0x01)
> > > HCI Event: Command Complete (0x0e) plen 4
> >       Write Sync Flow Control Enable (0x03|0x002f) ncmd 1
> >         Status: Success (0x00)
> >
> > And then test it by sending an empty packet to confirm the controller
> > will generate HCI_EV_NUM_COMP_PKTS events:
>
> It's not doing this any more in this version.

Oh yeah, forgot to remove it from the patch description.

> >
> > sco-tester[40]: < SCO Data TX:.. flags 0x00 dlen 9
> > > HCI Event: Number of Completed P.. (0x13) plen 5
> >         Num handles: 1
> >         Handle: 42 Address: 00:AA:01:01:00:00 (Intel Corporation)
> >         Count: 1
> >         #103: len 10 (40 Kb/s)
> >         Latency: 2 msec (2-2 msec ~2 msec)
> >
> > Fixes: 7fedd3bb6b77 ("Bluetooth: Prioritize SCO traffic")
> > Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>
> > ---
> >  include/net/bluetooth/hci.h      | 13 +++++++
> >  include/net/bluetooth/hci_core.h |  1 +
> >  net/bluetooth/hci_core.c         | 67 ++++++++++++++++----------------
> >  net/bluetooth/hci_event.c        |  2 +
> >  net/bluetooth/hci_sync.c         | 24 ++++++++++++
> >  5 files changed, 74 insertions(+), 33 deletions(-)
> >
> > diff --git a/include/net/bluetooth/hci.h b/include/net/bluetooth/hci.h
> > index b99818df8ee7..3c8f95174fcf 100644
> > --- a/include/net/bluetooth/hci.h
> > +++ b/include/net/bluetooth/hci.h
> > @@ -208,6 +208,13 @@ enum {
> >        */
> >       HCI_QUIRK_WIDEBAND_SPEECH_SUPPORTED,
> >
> > +     /* When this quirk is set consider Sync Flow Control as supported by
> > +      * the driver.
> > +      *
> > +      * This quirk must be set before hci_register_dev is called.
> > +      */
> > +     HCI_QUIRK_SYNC_FLOWCTL_SUPPORTED,
> > +
> >       /* When this quirk is set, the LE states reported through the
> >        * HCI_LE_READ_SUPPORTED_STATES are invalid/broken.
> >        *
> > @@ -448,6 +455,7 @@ enum {
> >       HCI_WIDEBAND_SPEECH_ENABLED,
> >       HCI_EVENT_FILTER_CONFIGURED,
> >       HCI_PA_SYNC,
> > +     HCI_SCO_FLOWCTL,
> >
> >       HCI_DUT_MODE,
> >       HCI_VENDOR_DIAG,
> > @@ -1544,6 +1552,11 @@ struct hci_rp_read_tx_power {
> >       __s8     tx_power;
> >  } __packed;
> >
> > +#define HCI_OP_WRITE_SYNC_FLOWCTL    0x0c2f
> > +struct hci_cp_write_sync_flowctl {
> > +     __u8     enable;
> > +} __packed;
> > +
> >  #define HCI_OP_READ_PAGE_SCAN_TYPE   0x0c46
> >  struct hci_rp_read_page_scan_type {
> >       __u8     status;
> > diff --git a/include/net/bluetooth/hci_core.h b/include/net/bluetooth/hci_core.h
> > index 7966db4038cc..f78e4298e39a 100644
> > --- a/include/net/bluetooth/hci_core.h
> > +++ b/include/net/bluetooth/hci_core.h
> > @@ -1858,6 +1858,7 @@ void hci_conn_del_sysfs(struct hci_conn *conn);
> >  #define lmp_hold_capable(dev)      ((dev)->features[0][0] & LMP_HOLD)
> >  #define lmp_sniff_capable(dev)     ((dev)->features[0][0] & LMP_SNIFF)
> >  #define lmp_park_capable(dev)      ((dev)->features[0][1] & LMP_PARK)
> > +#define lmp_sco_capable(dev)       ((dev)->features[0][1] & LMP_SCO)
> >  #define lmp_inq_rssi_capable(dev)  ((dev)->features[0][3] & LMP_RSSI_INQ)
> >  #define lmp_esco_capable(dev)      ((dev)->features[0][3] & LMP_ESCO)
> >  #define lmp_bredr_capable(dev)     (!((dev)->features[0][4] & LMP_NO_BREDR))
> > diff --git a/net/bluetooth/hci_core.c b/net/bluetooth/hci_core.c
> > index 012fc107901a..efba2b539902 100644
> > --- a/net/bluetooth/hci_core.c
> > +++ b/net/bluetooth/hci_core.c
> > @@ -3552,51 +3552,52 @@ static void __check_timeout(struct hci_dev *hdev, unsigned int cnt, u8 type)
> >  }
> >
> >  /* Schedule SCO */
> > -static void hci_sched_sco(struct hci_dev *hdev)
> > +static void hci_sched_sco_type(struct hci_dev *hdev, __u8 type)
> >  {
> >       struct hci_conn *conn;
> >       struct sk_buff *skb;
> >       int quote;
> > +     unsigned int pkts;
> >
> > -     BT_DBG("%s", hdev->name);
> > +     bt_dev_dbg(hdev, "type %u", type);
> >
> > -     if (!hci_conn_num(hdev, SCO_LINK))
> > +     if (!hci_conn_num(hdev, type))
> >               return;
> >
> > -     while (hdev->sco_cnt && (conn = hci_low_sent(hdev, SCO_LINK, &quote))) {
> > +     /* Use sco_pkts if flow control has not been enabled yet which will
> > +      * limit the amount of buffer sent in a row.
> > +      */
> > +     if (!hci_dev_test_flag(hdev, HCI_SCO_FLOWCTL))
> > +             pkts = hdev->sco_pkts;
> > +     else
> > +             pkts = hdev->sco_cnt;
> > +
> > +     if (!pkts)
> > +             return;
> > +
> > +     while (pkts && (conn = hci_low_sent(hdev, type, &quote))) {
> >               while (quote-- && (skb = skb_dequeue(&conn->data_q))) {
>
> hci_low_sent -> hci_quote_sent uses the current value of hdev->sco_cnt
> to determine `quote`, which can then be larger than pkts, possibly
> causing it to underflow here.

Well there is a check for pkts not underflow (< 0), or do you mean
something else?

> I guess this is why the other sched() functions are doing the (*cnt)--
> thing.

Right, we might want to switch to do that here as well, that said
perhaps hci_low_sent shouldn't be using sco_cnt if HCI_SCO_FLOWCTL is
not enabled.

>
> >                       BT_DBG("skb %p len %d", skb, skb->len);
> >                       hci_send_frame(hdev, skb);
> >
> > +                     pkts--;
> > +
> > +                     if (hdev->sco_cnt > 0)
> > +                             hdev->sco_cnt--;
> > +
> >                       conn->sent++;
> >                       if (conn->sent == ~0)
> >                               conn->sent = 0;
> >               }
> >       }
> > -}
> >
> > -static void hci_sched_esco(struct hci_dev *hdev)
> > -{
> > -     struct hci_conn *conn;
> > -     struct sk_buff *skb;
> > -     int quote;
> > -
> > -     BT_DBG("%s", hdev->name);
> > -
> > -     if (!hci_conn_num(hdev, ESCO_LINK))
> > -             return;
> > -
> > -     while (hdev->sco_cnt && (conn = hci_low_sent(hdev, ESCO_LINK,
> > -                                                  &quote))) {
> > -             while (quote-- && (skb = skb_dequeue(&conn->data_q))) {
> > -                     BT_DBG("skb %p len %d", skb, skb->len);
> > -                     hci_send_frame(hdev, skb);
> > -
> > -                     conn->sent++;
> > -                     if (conn->sent == ~0)
> > -                             conn->sent = 0;
> > -             }
> > -     }
> > +     /* Rescheduled if all packets were sent and flow control is not enabled
> > +      * as there could be more packets queued that could not be sent and
> > +      * since no HCI_EV_NUM_COMP_PKTS event will be generated the reschedule
> > +      * needs to be forced.
> > +      */
> > +     if (!pkts && !hci_dev_test_flag(hdev, HCI_SCO_FLOWCTL))
> > +             queue_work(hdev->workqueue, &hdev->tx_work);
> >  }
> >
> >  static void hci_sched_acl_pkt(struct hci_dev *hdev)
> > @@ -3632,8 +3633,8 @@ static void hci_sched_acl_pkt(struct hci_dev *hdev)
> >                       chan->conn->sent++;
> >
> >                       /* Send pending SCO packets right away */
> > -                     hci_sched_sco(hdev);
> > -                     hci_sched_esco(hdev);
> > +                     hci_sched_sco_type(hdev, SCO_LINK);
> > +                     hci_sched_sco_type(hdev, ESCO_LINK);
> >               }
> >       }
> >
> > @@ -3688,8 +3689,8 @@ static void hci_sched_le(struct hci_dev *hdev)
> >                       chan->conn->sent++;
> >
> >                       /* Send pending SCO packets right away */
> > -                     hci_sched_sco(hdev);
> > -                     hci_sched_esco(hdev);
> > +                     hci_sched_sco_type(hdev, SCO_LINK);
> > +                     hci_sched_sco_type(hdev, ESCO_LINK);
> >               }
> >       }
> >
> > @@ -3734,8 +3735,8 @@ static void hci_tx_work(struct work_struct *work)
> >
> >       if (!hci_dev_test_flag(hdev, HCI_USER_CHANNEL)) {
> >               /* Schedule queues and send stuff to HCI driver */
> > -             hci_sched_sco(hdev);
> > -             hci_sched_esco(hdev);
> > +             hci_sched_sco_type(hdev, SCO_LINK);
> > +             hci_sched_sco_type(hdev, ESCO_LINK);
> >               hci_sched_iso(hdev);
> >               hci_sched_acl(hdev);
> >               hci_sched_le(hdev);
> > diff --git a/net/bluetooth/hci_event.c b/net/bluetooth/hci_event.c
> > index 19e19c9f5e68..6d0138b778aa 100644
> > --- a/net/bluetooth/hci_event.c
> > +++ b/net/bluetooth/hci_event.c
> > @@ -4445,9 +4445,11 @@ static void hci_num_comp_pkts_evt(struct hci_dev *hdev, void *data,
> >                       break;
> >
> >               case SCO_LINK:
> > +             case ESCO_LINK:
> >                       hdev->sco_cnt += count;
> >                       if (hdev->sco_cnt > hdev->sco_pkts)
> >                               hdev->sco_cnt = hdev->sco_pkts;
> > +
> >                       break;
> >
> >               case ISO_LINK:
> > diff --git a/net/bluetooth/hci_sync.c b/net/bluetooth/hci_sync.c
> > index c4c2cf51b219..609b035e5c90 100644
> > --- a/net/bluetooth/hci_sync.c
> > +++ b/net/bluetooth/hci_sync.c
> > @@ -3769,6 +3769,28 @@ static int hci_write_ca_timeout_sync(struct hci_dev *hdev)
> >                                    sizeof(param), &param, HCI_CMD_TIMEOUT);
> >  }
> >
> > +/* Enable SCO flow control if supported */
> > +static int hci_write_sync_flowctl_sync(struct hci_dev *hdev)
> > +{
> > +     struct hci_cp_write_sync_flowctl cp;
> > +     int err;
> > +
> > +     /* Check if the controller supports SCO and HCI_OP_WRITE_SYNC_FLOWCTL */
> > +     if (!lmp_sco_capable(hdev) || !(hdev->commands[10] & BIT(4)) ||
> > +         !test_bit(HCI_QUIRK_SYNC_FLOWCTL_SUPPORTED, &hdev->quirks))
> > +             return 0;
> > +
> > +     memset(&cp, 0, sizeof(cp));
> > +     cp.enable = 0x01;
> > +
> > +     err = __hci_cmd_sync_status(hdev, HCI_OP_WRITE_SYNC_FLOWCTL,
> > +                                 sizeof(cp), &cp, HCI_CMD_TIMEOUT);
> > +     if (!err)
> > +             hci_dev_set_flag(hdev, HCI_SCO_FLOWCTL);
> > +
> > +     return err;
> > +}
> > +
> >  /* BR Controller init stage 2 command sequence */
> >  static const struct hci_init_stage br_init2[] = {
> >       /* HCI_OP_READ_BUFFER_SIZE */
> > @@ -3787,6 +3809,8 @@ static const struct hci_init_stage br_init2[] = {
> >       HCI_INIT(hci_clear_event_filter_sync),
> >       /* HCI_OP_WRITE_CA_TIMEOUT */
> >       HCI_INIT(hci_write_ca_timeout_sync),
> > +     /* HCI_OP_WRITE_SYNC_FLOWCTL */
> > +     HCI_INIT(hci_write_sync_flowctl_sync),
> >       {}
> >  };
> >
>
diff mbox series

Patch

diff --git a/include/net/bluetooth/hci.h b/include/net/bluetooth/hci.h
index b99818df8ee7..3c8f95174fcf 100644
--- a/include/net/bluetooth/hci.h
+++ b/include/net/bluetooth/hci.h
@@ -208,6 +208,13 @@  enum {
 	 */
 	HCI_QUIRK_WIDEBAND_SPEECH_SUPPORTED,
 
+	/* When this quirk is set consider Sync Flow Control as supported by
+	 * the driver.
+	 *
+	 * This quirk must be set before hci_register_dev is called.
+	 */
+	HCI_QUIRK_SYNC_FLOWCTL_SUPPORTED,
+
 	/* When this quirk is set, the LE states reported through the
 	 * HCI_LE_READ_SUPPORTED_STATES are invalid/broken.
 	 *
@@ -448,6 +455,7 @@  enum {
 	HCI_WIDEBAND_SPEECH_ENABLED,
 	HCI_EVENT_FILTER_CONFIGURED,
 	HCI_PA_SYNC,
+	HCI_SCO_FLOWCTL,
 
 	HCI_DUT_MODE,
 	HCI_VENDOR_DIAG,
@@ -1544,6 +1552,11 @@  struct hci_rp_read_tx_power {
 	__s8     tx_power;
 } __packed;
 
+#define HCI_OP_WRITE_SYNC_FLOWCTL	0x0c2f
+struct hci_cp_write_sync_flowctl {
+	__u8     enable;
+} __packed;
+
 #define HCI_OP_READ_PAGE_SCAN_TYPE	0x0c46
 struct hci_rp_read_page_scan_type {
 	__u8     status;
diff --git a/include/net/bluetooth/hci_core.h b/include/net/bluetooth/hci_core.h
index 7966db4038cc..f78e4298e39a 100644
--- a/include/net/bluetooth/hci_core.h
+++ b/include/net/bluetooth/hci_core.h
@@ -1858,6 +1858,7 @@  void hci_conn_del_sysfs(struct hci_conn *conn);
 #define lmp_hold_capable(dev)      ((dev)->features[0][0] & LMP_HOLD)
 #define lmp_sniff_capable(dev)     ((dev)->features[0][0] & LMP_SNIFF)
 #define lmp_park_capable(dev)      ((dev)->features[0][1] & LMP_PARK)
+#define lmp_sco_capable(dev)       ((dev)->features[0][1] & LMP_SCO)
 #define lmp_inq_rssi_capable(dev)  ((dev)->features[0][3] & LMP_RSSI_INQ)
 #define lmp_esco_capable(dev)      ((dev)->features[0][3] & LMP_ESCO)
 #define lmp_bredr_capable(dev)     (!((dev)->features[0][4] & LMP_NO_BREDR))
diff --git a/net/bluetooth/hci_core.c b/net/bluetooth/hci_core.c
index 012fc107901a..efba2b539902 100644
--- a/net/bluetooth/hci_core.c
+++ b/net/bluetooth/hci_core.c
@@ -3552,51 +3552,52 @@  static void __check_timeout(struct hci_dev *hdev, unsigned int cnt, u8 type)
 }
 
 /* Schedule SCO */
-static void hci_sched_sco(struct hci_dev *hdev)
+static void hci_sched_sco_type(struct hci_dev *hdev, __u8 type)
 {
 	struct hci_conn *conn;
 	struct sk_buff *skb;
 	int quote;
+	unsigned int pkts;
 
-	BT_DBG("%s", hdev->name);
+	bt_dev_dbg(hdev, "type %u", type);
 
-	if (!hci_conn_num(hdev, SCO_LINK))
+	if (!hci_conn_num(hdev, type))
 		return;
 
-	while (hdev->sco_cnt && (conn = hci_low_sent(hdev, SCO_LINK, &quote))) {
+	/* Use sco_pkts if flow control has not been enabled yet which will
+	 * limit the amount of buffer sent in a row.
+	 */
+	if (!hci_dev_test_flag(hdev, HCI_SCO_FLOWCTL))
+		pkts = hdev->sco_pkts;
+	else
+		pkts = hdev->sco_cnt;
+
+	if (!pkts)
+		return;
+
+	while (pkts && (conn = hci_low_sent(hdev, type, &quote))) {
 		while (quote-- && (skb = skb_dequeue(&conn->data_q))) {
 			BT_DBG("skb %p len %d", skb, skb->len);
 			hci_send_frame(hdev, skb);
 
+			pkts--;
+
+			if (hdev->sco_cnt > 0)
+				hdev->sco_cnt--;
+
 			conn->sent++;
 			if (conn->sent == ~0)
 				conn->sent = 0;
 		}
 	}
-}
 
-static void hci_sched_esco(struct hci_dev *hdev)
-{
-	struct hci_conn *conn;
-	struct sk_buff *skb;
-	int quote;
-
-	BT_DBG("%s", hdev->name);
-
-	if (!hci_conn_num(hdev, ESCO_LINK))
-		return;
-
-	while (hdev->sco_cnt && (conn = hci_low_sent(hdev, ESCO_LINK,
-						     &quote))) {
-		while (quote-- && (skb = skb_dequeue(&conn->data_q))) {
-			BT_DBG("skb %p len %d", skb, skb->len);
-			hci_send_frame(hdev, skb);
-
-			conn->sent++;
-			if (conn->sent == ~0)
-				conn->sent = 0;
-		}
-	}
+	/* Rescheduled if all packets were sent and flow control is not enabled
+	 * as there could be more packets queued that could not be sent and
+	 * since no HCI_EV_NUM_COMP_PKTS event will be generated the reschedule
+	 * needs to be forced.
+	 */
+	if (!pkts && !hci_dev_test_flag(hdev, HCI_SCO_FLOWCTL))
+		queue_work(hdev->workqueue, &hdev->tx_work);
 }
 
 static void hci_sched_acl_pkt(struct hci_dev *hdev)
@@ -3632,8 +3633,8 @@  static void hci_sched_acl_pkt(struct hci_dev *hdev)
 			chan->conn->sent++;
 
 			/* Send pending SCO packets right away */
-			hci_sched_sco(hdev);
-			hci_sched_esco(hdev);
+			hci_sched_sco_type(hdev, SCO_LINK);
+			hci_sched_sco_type(hdev, ESCO_LINK);
 		}
 	}
 
@@ -3688,8 +3689,8 @@  static void hci_sched_le(struct hci_dev *hdev)
 			chan->conn->sent++;
 
 			/* Send pending SCO packets right away */
-			hci_sched_sco(hdev);
-			hci_sched_esco(hdev);
+			hci_sched_sco_type(hdev, SCO_LINK);
+			hci_sched_sco_type(hdev, ESCO_LINK);
 		}
 	}
 
@@ -3734,8 +3735,8 @@  static void hci_tx_work(struct work_struct *work)
 
 	if (!hci_dev_test_flag(hdev, HCI_USER_CHANNEL)) {
 		/* Schedule queues and send stuff to HCI driver */
-		hci_sched_sco(hdev);
-		hci_sched_esco(hdev);
+		hci_sched_sco_type(hdev, SCO_LINK);
+		hci_sched_sco_type(hdev, ESCO_LINK);
 		hci_sched_iso(hdev);
 		hci_sched_acl(hdev);
 		hci_sched_le(hdev);
diff --git a/net/bluetooth/hci_event.c b/net/bluetooth/hci_event.c
index 19e19c9f5e68..6d0138b778aa 100644
--- a/net/bluetooth/hci_event.c
+++ b/net/bluetooth/hci_event.c
@@ -4445,9 +4445,11 @@  static void hci_num_comp_pkts_evt(struct hci_dev *hdev, void *data,
 			break;
 
 		case SCO_LINK:
+		case ESCO_LINK:
 			hdev->sco_cnt += count;
 			if (hdev->sco_cnt > hdev->sco_pkts)
 				hdev->sco_cnt = hdev->sco_pkts;
+
 			break;
 
 		case ISO_LINK:
diff --git a/net/bluetooth/hci_sync.c b/net/bluetooth/hci_sync.c
index c4c2cf51b219..609b035e5c90 100644
--- a/net/bluetooth/hci_sync.c
+++ b/net/bluetooth/hci_sync.c
@@ -3769,6 +3769,28 @@  static int hci_write_ca_timeout_sync(struct hci_dev *hdev)
 				     sizeof(param), &param, HCI_CMD_TIMEOUT);
 }
 
+/* Enable SCO flow control if supported */
+static int hci_write_sync_flowctl_sync(struct hci_dev *hdev)
+{
+	struct hci_cp_write_sync_flowctl cp;
+	int err;
+
+	/* Check if the controller supports SCO and HCI_OP_WRITE_SYNC_FLOWCTL */
+	if (!lmp_sco_capable(hdev) || !(hdev->commands[10] & BIT(4)) ||
+	    !test_bit(HCI_QUIRK_SYNC_FLOWCTL_SUPPORTED, &hdev->quirks))
+		return 0;
+
+	memset(&cp, 0, sizeof(cp));
+	cp.enable = 0x01;
+
+	err = __hci_cmd_sync_status(hdev, HCI_OP_WRITE_SYNC_FLOWCTL,
+				    sizeof(cp), &cp, HCI_CMD_TIMEOUT);
+	if (!err)
+		hci_dev_set_flag(hdev, HCI_SCO_FLOWCTL);
+
+	return err;
+}
+
 /* BR Controller init stage 2 command sequence */
 static const struct hci_init_stage br_init2[] = {
 	/* HCI_OP_READ_BUFFER_SIZE */
@@ -3787,6 +3809,8 @@  static const struct hci_init_stage br_init2[] = {
 	HCI_INIT(hci_clear_event_filter_sync),
 	/* HCI_OP_WRITE_CA_TIMEOUT */
 	HCI_INIT(hci_write_ca_timeout_sync),
+	/* HCI_OP_WRITE_SYNC_FLOWCTL */
+	HCI_INIT(hci_write_sync_flowctl_sync),
 	{}
 };