use CANON_USB_CONTROL_GET_ZOOM_POS to get and set zoom levels

from "Daniel P. Berrange" <dan@berrange.com>                                                                                                                                                


git-svn-id: https://svn.code.sf.net/p/gphoto/code/trunk/libgphoto2@14148 67ed7778-7388-44ab-90cf-0a291f65f57c

3 files changed, 63 insertions, 3 deletions

diff --git a/camlibs/canon/canon.c b/camlibs/canon/canon.c
index aa99e3636..72819d9e6 100644
--- a/camlibs/canon/canon.c
+++ b/camlibs/canon/canon.c
@@ -2027,6 +2027,65 @@ canon_int_set_zoom (Camera *camera, unsigned char zoom_level,
 
 
 /**
+ * canon_int_get_zoom
+ * @camera: camera to work with
+ * @zoom_level: pointer to hold returned zoom level - A40: 1..10; G1: 0..40 (pMaxOpticalZoomPos*4)
+ * @context: context for error reporting
+ *
+ * Gets the camera's zoom. Only tested for G1 via USB.
+ *
+ * Returns: gphoto2 error code
+ *
+ */
+int
+canon_int_get_zoom (Camera *camera, unsigned char *zoom_level,
+                    GPContext *context)
+{
+        unsigned char *msg = NULL;
+        unsigned int datalen = 0;
+        unsigned char payload[0x4c];
+        int payloadlen;
+        char desc[128];
+
+        *zoom_level = 0;
+        GP_DEBUG ("canon_int_get_zoom() called");
+
+        payloadlen = canon_int_pack_control_subcmd( payload,
+                                                    CANON_USB_CONTROL_GET_ZOOM_POS,
+                                                    0, 0, desc );
+
+        if ( camera->pl->md->model == CANON_CLASS_6 ) {
+                /* Newer protocol uses a different code, but with same
+                 * response. It also needs an extra zero byte at the
+                 * end. */
+                payload[payloadlen++] = 0;
+                msg = canon_usb_dialogue ( camera,
+                                           CANON_USB_FUNCTION_CONTROL_CAMERA_2,
+                                           &datalen, payload, payloadlen );
+        }
+        else
+                msg = canon_usb_dialogue ( camera,
+                                           CANON_USB_FUNCTION_CONTROL_CAMERA,
+                                           &datalen, payload, payloadlen );
+        if ( msg == NULL  && datalen != 0x1c) {
+                /* ERROR */
+                GP_DEBUG ("%s datalen=%x",
+                          desc, datalen);
+                return GP_ERROR_CORRUPTED_DATA;
+        }
+
+        *zoom_level = msg[12];
+
+        msg = NULL;
+        datalen = 0;
+
+        GP_DEBUG ("canon_int_get_zoom() finished successfully level=%d", *zoom_level);
+
+        return GP_OK;
+}
+
+
+/**
  * canon_int_set_image_format
  * @camera: camera to work with
  * @res_byte1: byte 1 of the 3-byte image format code
diff --git a/camlibs/canon/canon.h b/camlibs/canon/canon.h
index d3e6d4422..4905c7db4 100644
--- a/camlibs/canon/canon.h
+++ b/camlibs/canon/canon.h
@@ -713,6 +713,7 @@ int canon_int_end_remote_control(Camera *camera, GPContext *context);
 int canon_int_set_beep(Camera *camera, canonBeepMode beep_mode, GPContext *context);
 int canon_int_set_flash(Camera *camera, canonFlashMode flash_mode, GPContext *context);
 int canon_int_set_zoom(Camera *camera, unsigned char zoom_level, GPContext *context);
+int canon_int_get_zoom(Camera *camera, unsigned char *zoom_level, GPContext *context);
 
 /*
  * introduced for capturing
diff --git a/camlibs/canon/library.c b/camlibs/canon/library.c
index 14eee9b55..6edc641d2 100644
--- a/camlibs/canon/library.c
+++ b/camlibs/canon/library.c
@@ -1577,6 +1577,7 @@ camera_get_config (Camera *camera, CameraWidget **window, GPContext *context)
 	time_t camtime;
 	char formatted_camera_time[30];
 	float zoom;
+	unsigned char zoomVal;
 
 	GP_DEBUG ("camera_get_config()");
 
@@ -1734,9 +1735,8 @@ camera_get_config (Camera *camera, CameraWidget **window, GPContext *context)
 	gp_widget_new (GP_WIDGET_RANGE, _("Zoom"), &t);
 	gp_widget_set_name (t, "zoom");
 	gp_widget_set_range (t, 0, 255, 1);
-	/* Set an unknown zoom level (at the moment we don't read the
-	 * zoom level */
-	zoom = -1;
+	canon_int_get_zoom(camera, &zoomVal, context);
+	zoom = zoomVal;
 	gp_widget_set_value (t, &zoom);
 	gp_widget_append (section, t);