Reset Aver cameras to their home position using an extension unit

Bug: b:139355993
Change-Id: If5a0ddae8b277f7487b7a3a4aa744a312a574181
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1841946Reviewed-by: Zachary Kuznia <zork@chromium.org>
Commit-Queue: Juan Pablo De Lima <jpdelima@chromium.org>
Auto-Submit: Juan Pablo De Lima <jpdelima@chromium.org>
Cr-Commit-Position: refs/heads/master@{#703888}

extensions/browser/api/webcam_private/v4l2_webcam.cc

@@ -21,19 +21,45 @@
 
 // GUID of the Extension Unit for Logitech CC3300e motor control:
 // {212de5ff-3080-2c4e-82d9-f587d00540bd}
-#define UVC_GUID_LOGITECH_CC3000E_MOTORS          \
- {0x21, 0x2d, 0xe5, 0xff, 0x30, 0x80, 0x2c, 0x4e, \
-  0x82, 0xd9, 0xf5, 0x87, 0xd0, 0x05, 0x40, 0xbd}
+#define UVC_GUID_LOGITECH_CC3000E_MOTORS                                    \
+  {                                                                         \
+    0x21, 0x2d, 0xe5, 0xff, 0x30, 0x80, 0x2c, 0x4e, 0x82, 0xd9, 0xf5, 0x87, \
+        0xd0, 0x05, 0x40, 0xbd                                              \
+  }
+
+// GUID of the Extension Unit for AVER XU1 motor control:
+// {cb666936-6e26-a047-8451-96ecf60330d6}
+#define UVC_GUID_AVER                                                       \
+  {                                                                         \
+    0xcb, 0x66, 0x69, 0x36, 0x6e, 0x26, 0xa0, 0x47, 0x84, 0x51, 0x96, 0xec, \
+        0xf6, 0x03, 0x30, 0xd6                                              \
+  }
 
 #define LOGITECH_MOTORCONTROL_PANTILT_CMD 2
+#define AVER_UVCX_UCAM_PRESET 0x12
 
 namespace {
 const int kLogitechMenuIndexGoHome = 2;
+const int kAverMenuIndexGoHome = 1;
 
 const uvc_menu_info kLogitechCmdMenu[] = {
   {1, "Set Preset"}, {2, "Get Preset"}, {3, "Go Home"}
 };
 
+// Preset 0 is equivalent to HOME in Aver cameras.
+const uvc_menu_info kAverPresetMenu[] = {
+    /*0*/ {0x0000, "Set Preset 0"},  /*1*/ {0x0001, "Restore preset 0"},
+    /*2*/ {0x0100, "Set Preset 1"},  /*3*/ {0x0101, "Restore preset 1"},
+    /*4*/ {0x0200, "Set Preset 2"},  /*5*/ {0x0202, "Restore preset 2"},
+    /*6*/ {0x0300, "Set Preset 3"},  /*7*/ {0x0303, "Restore preset 3"},
+    /*8*/ {0x0400, "Set Preset 4"},  /*9*/ {0x0404, "Restore preset 4"},
+    /*10*/ {0x0500, "Set Preset 5"}, /*11*/ {0x0505, "Restore preset 5"},
+    /*12*/ {0x0600, "Set Preset 6"}, /*13*/ {0x0606, "Restore preset 6"},
+    /*14*/ {0x0700, "Set Preset 7"}, /*15*/ {0x0707, "Restore preset 7"},
+    /*16*/ {0x0800, "Set Preset 8"}, /*17*/ {0x0808, "Restore preset 8"},
+    /*18*/ {0x0900, "Set Preset 9"}, /*19*/ {0x0909, "Restore preset 9"},
+};
+
 const uvc_xu_control_mapping kLogitechCmdMapping = {
     V4L2_CID_PANTILT_CMD,
     "Pan/Tilt Go",
@@ -69,6 +95,19 @@ const uvc_xu_control_mapping kLogitechTiltAbsoluteMapping = {
     UVC_CTRL_DATA_TYPE_SIGNED,
 };
 
+const uvc_xu_control_mapping kAverCmdMapping = {
+    V4L2_CID_PANTILT_CMD,
+    "PTZ Preset",
+    UVC_GUID_AVER,
+    AVER_UVCX_UCAM_PRESET,
+    24,
+    0,
+    V4L2_CTRL_TYPE_MENU,
+    UVC_CTRL_DATA_TYPE_ENUM,
+    const_cast<uvc_menu_info*>(kAverPresetMenu),
+    base::size(kAverPresetMenu),
+};
+
 }  // namespace
 
 namespace extensions {
@@ -94,6 +133,14 @@ bool V4L2Webcam::EnsureLogitechCommandsMapped() {
   return res >= 0 || errno == EEXIST || errno == EFAULT;
 }
 
+bool V4L2Webcam::EnsureAverCommandsMapped() {
+  int res = HANDLE_EINTR(ioctl(fd_.get(), UVCIOC_CTRL_MAP, &kAverCmdMapping));
+  // If mapping is successful or it's already mapped, this is an Aver camera.
+  // NOTE: On success, occasionally EFAULT is returned.  On a real error,
+  // ENOMEM, EPERM, EINVAL, or EOVERFLOW should be returned.
+  return res >= 0 || errno == EEXIST || errno == EFAULT;
+}
+
 bool V4L2Webcam::SetWebcamParameter(int fd, uint32_t control_id, int value) {
   // Try to map the V4L2 control to the Logitech extension unit. If the
   // connected camera does not implement these extension unit this will just
@@ -251,6 +298,12 @@ void V4L2Webcam::Reset(bool pan,
         callback.Run(false);
         return;
       }
+    } else if (EnsureAverCommandsMapped()) {
+      if (!SetWebcamParameter(fd_.get(), V4L2_CID_PANTILT_CMD,
+                              kAverMenuIndexGoHome)) {
+        callback.Run(false);
+        return;
+      }
     } else {
       if (pan) {
         struct v4l2_control v4l2_ctrl = {V4L2_CID_PAN_RESET};

extensions/browser/api/webcam_private/v4l2_webcam.h

@@ -22,6 +22,7 @@ class V4L2Webcam : public Webcam {
  private:
   ~V4L2Webcam() override;
   bool EnsureLogitechCommandsMapped();
+  bool EnsureAverCommandsMapped();
   static bool SetWebcamParameter(int fd, uint32_t control_id, int value);
   static bool GetWebcamParameter(int fd,
                                  uint32_t control_id,