Re: [PATCH v2 1/2] Bluetooth: btusb: support link statistics telemetry events

From: Luiz Augusto von Dentz
Date: Tue Apr 13 2021 - 18:02:16 EST


Hi Joseph,

On Tue, Apr 13, 2021 at 12:45 AM Joseph Hwang <josephsih@xxxxxxxxxxxx> wrote:
>
> From: Chethan T N <chethan.tumkur.narayan@xxxxxxxxx>
>
> This patch supports the link statistics telemetry events for
> Intel controllers
>
> To avoid the overhead, this debug feature is disabled by default.
>
> Reviewed-by: Miao-chen Chou <mcchou@xxxxxxxxxxxx>
> Signed-off-by: Chethan T N <chethan.tumkur.narayan@xxxxxxxxx>
> Signed-off-by: Kiran K <kiran.k@xxxxxxxxx>
> Signed-off-by: Joseph Hwang <josephsih@xxxxxxxxxxxx>
> ---
>
> Changes in v2:
> - take care of intel_newgen as well as intel_new
> - fix the long-line issue
>
> drivers/bluetooth/btintel.c | 20 +++++++++++++++++++-
> drivers/bluetooth/btusb.c | 18 ------------------
> 2 files changed, 19 insertions(+), 19 deletions(-)
>
> diff --git a/drivers/bluetooth/btintel.c b/drivers/bluetooth/btintel.c
> index e44b6993cf91..de1dbdc01e5a 100644
> --- a/drivers/bluetooth/btintel.c
> +++ b/drivers/bluetooth/btintel.c
> @@ -1248,8 +1248,10 @@ EXPORT_SYMBOL_GPL(btintel_read_debug_features);
> int btintel_set_debug_features(struct hci_dev *hdev,
> const struct intel_debug_features *features)
> {
> - u8 mask[11] = { 0x0a, 0x92, 0x02, 0x07, 0x00, 0x00, 0x00, 0x00,
> + u8 mask[11] = { 0x0a, 0x92, 0x02, 0x7f, 0x00, 0x00, 0x00, 0x00,
> 0x00, 0x00, 0x00 };
> + u8 period[5] = { 0x04, 0x91, 0x02, 0x01, 0x00 };
> + u8 trace_enable = 0x02;
> struct sk_buff *skb;

Instead of using a byte array and custo opcode I would recommend we
start adding proper defines for Intel vendor opcodes with structs for
them, similar opcodes and structs are also very useful for adding
support for btmon, in fact I would start with btmon first and only
when we have proper decoding support start changing the kernel parts
so you can actually add btmon output to the patch description here.

> if (!features)
> @@ -1266,8 +1268,24 @@ int btintel_set_debug_features(struct hci_dev *hdev,
> PTR_ERR(skb));
> return PTR_ERR(skb);
> }
> + kfree_skb(skb);
> +
> + skb = __hci_cmd_sync(hdev, 0xfc8b, 5, period, HCI_INIT_TIMEOUT);
> + if (IS_ERR(skb)) {
> + bt_dev_err(hdev, "Setting periodicity for link statistics traces failed (%ld)",
> + PTR_ERR(skb));
> + return PTR_ERR(skb);
> + }
> + kfree_skb(skb);
>
> + skb = __hci_cmd_sync(hdev, 0xfca1, 1, &trace_enable, HCI_INIT_TIMEOUT);
> + if (IS_ERR(skb)) {
> + bt_dev_err(hdev, "Enable tracing of link statistics events failed (%ld)",
> + PTR_ERR(skb));
> + return PTR_ERR(skb);
> + }
> kfree_skb(skb);
> +
> return 0;
> }
> EXPORT_SYMBOL_GPL(btintel_set_debug_features);
> diff --git a/drivers/bluetooth/btusb.c b/drivers/bluetooth/btusb.c
> index 192cb8c191bc..f29946f15f59 100644
> --- a/drivers/bluetooth/btusb.c
> +++ b/drivers/bluetooth/btusb.c
> @@ -2811,7 +2811,6 @@ static int btusb_setup_intel_new(struct hci_dev *hdev)
> u32 boot_param;
> char ddcname[64];
> int err;
> - struct intel_debug_features features;
>
> BT_DBG("%s", hdev->name);
>
> @@ -2865,14 +2864,6 @@ static int btusb_setup_intel_new(struct hci_dev *hdev)
> btintel_load_ddc_config(hdev, ddcname);
> }
>
> - /* Read the Intel supported features and if new exception formats
> - * supported, need to load the additional DDC config to enable.
> - */
> - btintel_read_debug_features(hdev, &features);
> -
> - /* Set DDC mask for available debug features */
> - btintel_set_debug_features(hdev, &features);
> -
> /* Read the Intel version information after loading the FW */
> err = btintel_read_version(hdev, &ver);
> if (err)
> @@ -2911,7 +2902,6 @@ static int btusb_setup_intel_newgen(struct hci_dev *hdev)
> u32 boot_param;
> char ddcname[64];
> int err;
> - struct intel_debug_features features;
> struct intel_version_tlv version;
>
> bt_dev_dbg(hdev, "");
> @@ -2961,14 +2951,6 @@ static int btusb_setup_intel_newgen(struct hci_dev *hdev)
> */
> btintel_load_ddc_config(hdev, ddcname);
>
> - /* Read the Intel supported features and if new exception formats
> - * supported, need to load the additional DDC config to enable.
> - */
> - btintel_read_debug_features(hdev, &features);
> -
> - /* Set DDC mask for available debug features */
> - btintel_set_debug_features(hdev, &features);
> -
> /* Read the Intel version information after loading the FW */
> err = btintel_read_version_tlv(hdev, &version);
> if (err)
> --
> 2.31.1.295.g9ea45b61b8-goog
>


--
Luiz Augusto von Dentz