Bluetooth: Add support for setting SSP debug mode

Enabling and disabling SSP debug mode is useful for development. This
adds a debugfs entry that allows to configure the SSP debug mode.

On purpose this has been implemented as debugfs entry and not a public
API since it is really only useful during testing and development.

Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>

4 files changed, 58 insertions, 1 deletions

diff --git a/include/net/bluetooth/hci.h b/include/net/bluetooth/hci.h
index 77a971aefcff..ac9c4a75e314 100644
--- a/include/net/bluetooth/hci.h
+++ b/include/net/bluetooth/hci.h
@@ -1043,6 +1043,8 @@ struct hci_rp_write_remote_amp_assoc {
         __u8     phy_handle;
 } __packed;
 
+#define HCI_OP_WRITE_SSP_DEBUG_MODE     0x1804
+
 #define HCI_OP_LE_SET_EVENT_MASK        0x2001
 struct hci_cp_le_set_event_mask {
         __u8     mask[8];
diff --git a/include/net/bluetooth/hci_core.h b/include/net/bluetooth/hci_core.h
index c689bcf4a0f7..d50cc7aca4e4 100644
--- a/include/net/bluetooth/hci_core.h
+++ b/include/net/bluetooth/hci_core.h
@@ -169,6 +169,7 @@ struct hci_dev {
         __u8            page_scan_type;
         __u16           le_scan_interval;
         __u16           le_scan_window;
+        __u8            ssp_debug_mode;
 
         __u16           devid_source;
         __u16           devid_vendor;
diff --git a/net/bluetooth/hci_core.c b/net/bluetooth/hci_core.c
index 384b9db16f69..2a9e92503fd6 100644
--- a/net/bluetooth/hci_core.c
+++ b/net/bluetooth/hci_core.c
@@ -303,6 +303,55 @@ static int auto_accept_delay_get(void *data, u64 *val)
 DEFINE_SIMPLE_ATTRIBUTE(auto_accept_delay_fops, auto_accept_delay_get,
                         auto_accept_delay_set, "%llu\n");
 
+static int ssp_debug_mode_set(void *data, u64 val)
+{
+        struct hci_dev *hdev = data;
+        struct sk_buff *skb;
+        __u8 mode;
+        int err;
+
+        if (val != 0 && val != 1)
+                return -EINVAL;
+
+        if (!test_bit(HCI_UP, &hdev->flags))
+                return -ENETDOWN;
+
+        hci_req_lock(hdev);
+        mode = val;
+        skb = __hci_cmd_sync(hdev, HCI_OP_WRITE_SSP_DEBUG_MODE, sizeof(mode),
+                             &mode, HCI_CMD_TIMEOUT);
+        hci_req_unlock(hdev);
+
+        if (IS_ERR(skb))
+                return PTR_ERR(skb);
+
+        err = -bt_to_errno(skb->data[0]);
+        kfree_skb(skb);
+
+        if (err < 0)
+                return err;
+
+        hci_dev_lock(hdev);
+        hdev->ssp_debug_mode = val;
+        hci_dev_unlock(hdev);
+
+        return 0;
+}
+
+static int ssp_debug_mode_get(void *data, u64 *val)
+{
+        struct hci_dev *hdev = data;
+
+        hci_dev_lock(hdev);
+        *val = hdev->ssp_debug_mode;
+        hci_dev_unlock(hdev);
+
+        return 0;
+}
+
+DEFINE_SIMPLE_ATTRIBUTE(ssp_debug_mode_fops, ssp_debug_mode_get,
+                        ssp_debug_mode_set, "%llu\n");
+
 static int idle_timeout_set(void *data, u64 val)
 {
         struct hci_dev *hdev = data;
@@ -1199,9 +1248,12 @@ static int __hci_init(struct hci_dev *hdev)
                                     hdev, &voice_setting_fops);
         }
 
-        if (lmp_ssp_capable(hdev))
+        if (lmp_ssp_capable(hdev)) {
                 debugfs_create_file("auto_accept_delay", 0644, hdev->debugfs,
                                     hdev, &auto_accept_delay_fops);
+                debugfs_create_file("ssp_debug_mode", 0644, hdev->debugfs,
+                                    hdev, &ssp_debug_mode_fops);
+        }
 
         if (lmp_sniff_capable(hdev)) {
                 debugfs_create_file("idle_timeout", 0644, hdev->debugfs,
diff --git a/net/bluetooth/hci_event.c b/net/bluetooth/hci_event.c
index 1214d4b6f541..5935f748c0f9 100644
--- a/net/bluetooth/hci_event.c
+++ b/net/bluetooth/hci_event.c
@@ -198,6 +198,8 @@ static void hci_cc_reset(struct hci_dev *hdev, struct sk_buff *skb)
 
         memset(hdev->scan_rsp_data, 0, sizeof(hdev->scan_rsp_data));
         hdev->scan_rsp_data_len = 0;
+
+        hdev->ssp_debug_mode = 0;
 }
 
 static void hci_cc_write_local_name(struct hci_dev *hdev, struct sk_buff *skb)