Re: [PATCH v5 2/4] Bluetooth: btbcm: Support pcm configuration

From: Marcel Holtmann
Date: Fri Nov 15 2019 - 02:54:32 EST


Hi Abhishek,

> Add BCM vendor specific command to configure PCM parameters. The new
> vendor opcode allows us to set the sco routing, the pcm interface rate,
> and a few other pcm specific options (frame sync, sync mode, and clock
> mode). See broadcom-bluetooth.txt in Documentation for more information
> about valid values for those settings.
>
> Here is an example trace where this opcode was used to configure
> a BCM4354:
>
> < HCI Command: Vendor (0x3f|0x001c) plen 5
> 01 02 00 01 01
>> HCI Event: Command Complete (0x0e) plen 4
> Vendor (0x3f|0x001c) ncmd 1
> Status: Success (0x00)
>
> We can read back the values as well with ocf 0x001d to confirm the
> values that were set:
> $ hcitool cmd 0x3f 0x001d
> < HCI Command: ogf 0x3f, ocf 0x001d, plen 0
>> HCI Event: 0x0e plen 9
> 01 1D FC 00 01 02 00 01 01
>
> Signed-off-by: Abhishek Pandit-Subedi <abhishekpandit@xxxxxxxxxxxx>
> ---
>
> Changes in v5: None
> Changes in v4: None
> Changes in v3: None
> Changes in v2: None
>
> drivers/bluetooth/btbcm.c | 19 +++++++++++++++++++
> drivers/bluetooth/btbcm.h | 8 ++++++++
> 2 files changed, 27 insertions(+)
>
> diff --git a/drivers/bluetooth/btbcm.c b/drivers/bluetooth/btbcm.c
> index 2d2e6d862068..53fd66a96e69 100644
> --- a/drivers/bluetooth/btbcm.c
> +++ b/drivers/bluetooth/btbcm.c
> @@ -105,6 +105,25 @@ int btbcm_set_bdaddr(struct hci_dev *hdev, const bdaddr_t *bdaddr)
> }
> EXPORT_SYMBOL_GPL(btbcm_set_bdaddr);
>
> +int btbcm_set_pcm_int_params(struct hci_dev *hdev,
> + const struct bcm_set_pcm_int_params *int_params)
> +{
> + struct sk_buff *skb;
> + int err;
> +
> + /* Vendor ocf 0x001c sets the pcm parameters and 0x001d reads it */

drop this comment.

> + skb = __hci_cmd_sync(hdev, 0xfc1c, 5, int_params, HCI_INIT_TIMEOUT);
> + if (IS_ERR(skb)) {
> + err = PTR_ERR(skb);
> + bt_dev_err(hdev, "BCM: Set PCM int params failed (%d)", err);
> + return err;
> + }
> + kfree_skb(skb);
> +
> + return 0;
> +}
> +EXPORT_SYMBOL_GPL(btbcm_set_pcm_int_params);
> +

Lets introduce two function here. btbcm_write_pcm_int_param and btbcm_read_pcm_int_param.

Regards

Marcel