Quelle  aosp.c   Sprache: C

// SPDX-License-Identifier: GPL-2.0-only
/*
 * Copyright (C) 2021 Intel Corporation
 */

#include <net/bluetooth/bluetooth.h>
#include <net/bluetooth/hci_core.h>

#include "aosp.h"

/* Command complete parameters of LE_Get_Vendor_Capabilities_Command
 * The parameters grow over time. The base version that declares the
 * version_supported field is v0.95. Refer to
 * https://cs.android.com/android/platform/superproject/+/master:system/
 *         bt/gd/hci/controller.cc;l=452?q=le_get_vendor_capabilities_handler
 */
struct aosp_rp_le_get_vendor_capa {
 /* v0.95: 15 octets */
 __u8 status;
 __u8 max_advt_instances;
 __u8 offloaded_resolution_of_private_address;
 __le16 total_scan_results_storage;
 __u8 max_irk_list_sz;
 __u8 filtering_support;
 __u8 max_filter;
 __u8 activity_energy_info_support;
 __le16 version_supported;
 __le16 total_num_of_advt_tracked;
 __u8 extended_scan_support;
 __u8 debug_logging_supported;
 /* v0.96: 16 octets */
 __u8 le_address_generation_offloading_support;
 /* v0.98: 21 octets */
 __le32 a2dp_source_offload_capability_mask;
 __u8 bluetooth_quality_report_support;
 /* v1.00: 25 octets */
 __le32 dynamic_audio_buffer_support;
} __packed;

#define VENDOR_CAPA_BASE_SIZE  15
#define VENDOR_CAPA_0_98_SIZE  21

void aosp_do_open(struct hci_dev *hdev)
{
 struct sk_buff *skb;
 struct aosp_rp_le_get_vendor_capa *rp;
 u16 version_supported;

 if (!hdev->aosp_capable)
  return;

 bt_dev_dbg(hdev, "Initialize AOSP extension");

 /* LE Get Vendor Capabilities Command */
 skb = __hci_cmd_sync(hdev, hci_opcode_pack(0x3f, 0x153), 0, NULL,
        HCI_CMD_TIMEOUT);
 if (IS_ERR_OR_NULL(skb)) {
  if (!skb)
   skb = ERR_PTR(-EIO);

  bt_dev_err(hdev, "AOSP get vendor capabilities (%ld)",
      PTR_ERR(skb));
  return;
 }

 /* A basic length check */
 if (skb->len < VENDOR_CAPA_BASE_SIZE)
  goto length_error;

 rp = (struct aosp_rp_le_get_vendor_capa *)skb->data;

 version_supported = le16_to_cpu(rp->version_supported);
 /* AOSP displays the version number like v0.98, v1.00, etc. */
 bt_dev_info(hdev, "AOSP extensions version v%u.%02u",
      version_supported >> 8, version_supported & 0xff);

 /* Do not support very old versions. */
 if (version_supported < 95) {
  bt_dev_warn(hdev, "AOSP capabilities version %u too old",
       version_supported);
  goto done;
 }

 if (version_supported < 98) {
  bt_dev_warn(hdev, "AOSP quality report is not supported");
  goto done;
 }

 if (skb->len < VENDOR_CAPA_0_98_SIZE)
  goto length_error;

 /* The bluetooth_quality_report_support is defined at version
 * v0.98. Refer to
 * https://cs.android.com/android/platform/superproject/+/
 *         master:system/bt/gd/hci/controller.cc;l=477
 */
 if (rp->bluetooth_quality_report_support) {
  hdev->aosp_quality_report = true;
  bt_dev_info(hdev, "AOSP quality report is supported");
 }

 goto done;

length_error:
 bt_dev_err(hdev, "AOSP capabilities length %d too short", skb->len);

done:
 kfree_skb(skb);
}

void aosp_do_close(struct hci_dev *hdev)
{
 if (!hdev->aosp_capable)
  return;

 bt_dev_dbg(hdev, "Cleanup of AOSP extension");
}

/* BQR command */
#define BQR_OPCODE   hci_opcode_pack(0x3f, 0x015e)

/* BQR report action */
#define REPORT_ACTION_ADD  0x00
#define REPORT_ACTION_DELETE  0x01
#define REPORT_ACTION_CLEAR  0x02

/* BQR event masks */
#define QUALITY_MONITORING  BIT(0)
#define APPRAOCHING_LSTO  BIT(1)
#define A2DP_AUDIO_CHOPPY  BIT(2)
#define SCO_VOICE_CHOPPY  BIT(3)

#define DEFAULT_BQR_EVENT_MASK (QUALITY_MONITORING | APPRAOCHING_LSTO | \
     A2DP_AUDIO_CHOPPY | SCO_VOICE_CHOPPY)

/* Reporting at milliseconds so as not to stress the controller too much.
 * Range: 0 ~ 65535 ms
 */
#define DEFALUT_REPORT_INTERVAL_MS 5000

struct aosp_bqr_cp {
 __u8 report_action;
 __u32 event_mask;
 __u16 min_report_interval;
} __packed;

static int enable_quality_report(struct hci_dev *hdev)
{
 struct sk_buff *skb;
 struct aosp_bqr_cp cp;

 cp.report_action = REPORT_ACTION_ADD;
 cp.event_mask = DEFAULT_BQR_EVENT_MASK;
 cp.min_report_interval = DEFALUT_REPORT_INTERVAL_MS;

 skb = __hci_cmd_sync(hdev, BQR_OPCODE, sizeof(cp), &cp,
        HCI_CMD_TIMEOUT);
 if (IS_ERR_OR_NULL(skb)) {
  if (!skb)
   skb = ERR_PTR(-EIO);

  bt_dev_err(hdev, "Enabling Android BQR failed (%ld)",
      PTR_ERR(skb));
  return PTR_ERR(skb);
 }

 kfree_skb(skb);
 return 0;
}

static int disable_quality_report(struct hci_dev *hdev)
{
 struct sk_buff *skb;
 struct aosp_bqr_cp cp = { 0 };

 cp.report_action = REPORT_ACTION_CLEAR;

 skb = __hci_cmd_sync(hdev, BQR_OPCODE, sizeof(cp), &cp,
        HCI_CMD_TIMEOUT);
 if (IS_ERR_OR_NULL(skb)) {
  if (!skb)
   skb = ERR_PTR(-EIO);

  bt_dev_err(hdev, "Disabling Android BQR failed (%ld)",
      PTR_ERR(skb));
  return PTR_ERR(skb);
 }

 kfree_skb(skb);
 return 0;
}

bool aosp_has_quality_report(struct hci_dev *hdev)
{
 return hdev->aosp_quality_report;
}

int aosp_set_quality_report(struct hci_dev *hdev, bool enable)
{
 if (!aosp_has_quality_report(hdev))
  return -EOPNOTSUPP;

 bt_dev_dbg(hdev, "quality report enable %d", enable);

 /* Enable or disable the quality report feature. */
 if (enable)
  return enable_quality_report(hdev);
 else
  return disable_quality_report(hdev);
}