Add HAL APIs to query cached scan results

Add HAL API to retrieve the on-chip scan results.

Bug: 232030878
Test: New API works fine
Change-Id: I0487d010078f4e33fef76a951cc87647746ac867

include/hardware_legacy/wifi_cached_scan_results.h

@@ -0,0 +1,92 @@
+/*
+ * Copyright (C) 2022 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#ifndef __WIFI_CACHED_SCAN_RESULTS_H__
+#define __WIFI_CACHED_SCAN_RESULTS_H__
+
+#include "wifi_hal.h"
+
+#define WIFI_CACHED_SCAN_RESULT_FLAGS_NONE                         (0)
+/* Element ID 61 (HT Operation) is present (see HT 7.3.2) */
+#define WIFI_CACHED_SCAN_RESULT_FLAGS_HT_OPS_PRESENT               (1 << 0)
+/* Element ID 192 (VHT Operation) is present (see VHT 8.4.2)  */
+#define WIFI_CACHED_SCAN_RESULT_FLAGS_VHT_OPS_PRESENT              (1 << 1)
+/* Element ID 255 + Extension 36 (HE Operation) is present
+ * (see 802.11ax 9.4.2.1)
+ */
+#define WIFI_CACHED_SCAN_RESULT_FLAGS_HE_OPS_PRESENT               (1 << 2)
+/* Element ID 255 + Extension 106 (HE Operation) is present
+ * (see 802.11be D1.5 9.4.2.1)
+ */
+#define WIFI_CACHED_SCAN_RESULT_FLAGS_EHT_OPS_PRESENT              (1 << 3)
+/* Element ID 127 (Extended Capabilities) is present, and bit 70
+ * (Fine Timing Measurement Responder) is set to 1
+ * (see IEEE Std 802.11-2016 9.4.2.27)
+ */
+#define WIFI_CACHED_SCAN_RESULT_FLAGS_IS_FTM_RESPONDER             (1 << 4)
+
+/**
+ * Provides information about a single access point (AP) detected in a scan.
+ */
+typedef struct {
+    /* Number of milliseconds prior to ts in the enclosing
+     * wifi_cached_scan_result_report struct when
+     * the probe response or beacon frame that
+     * was used to populate this structure was received.
+     */
+    u32 age_ms;
+    /* The Capability Information field */
+    u16 capability;
+    /* null terminated */
+    u8 ssid[33];
+    u8 ssid_len;
+    u8 bssid[6];
+    /* A set of flags from WIFI_CACHED_SCAN_RESULT_FLAGS_* */
+    u8 flags;
+    s8  rssi;
+    wifi_channel_spec chanspec;
+}wifi_cached_scan_result;
+
+/*
+ * Data structure sent with events of type WifiCachedScanResult.
+ */
+typedef struct  {
+    /* time since boot (in microsecond) when the result was retrieved */
+    wifi_timestamp ts;
+    /* If 0, indicates that all frequencies in current regulation were
+     * scanned. Otherwise, indicates the number of frequencies scanned, as
+     * specified in scanned_freq_list.
+     */
+    u16 scanned_freq_num;
+    /* Pointer to an array containing scanned_freq_num values comprising the
+     * set of frequencies that were scanned. Frequencies are specified as
+     * channel center frequencies in MHz. May be NULL if scannedFreqListLen is
+     * 0.
+     */
+    const u32 *scanned_freq_list;
+    /* The total number of cached results returned. */
+    u8 result_cnt;
+    /* Pointer to an array containing result_cnt entries. May be NULL if
+     * result_cnt is 0.
+     */
+    const wifi_cached_scan_result *results;
+} wifi_cached_scan_report;
+
+/* callback for reporting cached scan report */
+typedef struct {
+  void (*on_cached_scan_results) (wifi_cached_scan_report *cache_report);
+} wifi_cached_scan_result_handler;
+#endif

include/hardware_legacy/wifi_hal.h

@@ -578,6 +578,7 @@ typedef struct {
 
 #include "gscan.h"
 #include "link_layer_stats.h"
+#include "wifi_cached_scan_results.h"
 #include "rtt.h"
 #include "tdls.h"
 #include "wifi_logger.h"
@@ -1025,7 +1026,14 @@ typedef struct {
     wifi_error (*wifi_enable_tx_power_limits) (wifi_interface_handle iface,
                                                bool isEnable);
 
-
+    /**@brief wifi_get_cached_scan_results
+     *        Retrieve scan results cached in wifi firmware
+     * @param wifi_interface_handle
+     * @param wifi_cached_scan_result_handler : callback function pointer
+     * @return Synchronous wifi_error
+     */
+    wifi_error (*wifi_get_cached_scan_results)(wifi_interface_handle iface,
+                                               wifi_cached_scan_result_handler handler);
     /*
      * when adding new functions make sure to add stubs in
      * hal_tool.cpp::init_wifi_stub_hal_func_table