drm/mgag200: Set .detect_ctx() and enable connector polling

Set .detect_ctx() in struct drm_connector_helper_funcs to the
common helper drm_connector_helper_detect_from_ddc() and enable
polling for the connector. Mgag200 will now test for the monitor's
presence by probing the DDC in regular intervals.

Signed-off-by: Thomas Zimmermann <[e-mail]>
Reviewed-by: Jocelyn Falempe <[e-mail]>
Link: https://patchwork.freedesktop.org/patch/msgid/[e-mail]

drivers/gpu/drm/mgag200/mgag200_g200.c

···
 		return ERR_PTR(ret);
 
 	drm_mode_config_reset(dev);
+	drm_kms_helper_poll_init(dev);
 
 	return mdev;
 }

drivers/gpu/drm/mgag200/mgag200_g200eh.c

···
 		return ERR_PTR(ret);
 
 	drm_mode_config_reset(dev);
+	drm_kms_helper_poll_init(dev);
 
 	return mdev;
 }

drivers/gpu/drm/mgag200/mgag200_g200eh3.c

···
 		return ERR_PTR(ret);
 
 	drm_mode_config_reset(dev);
+	drm_kms_helper_poll_init(dev);
 
 	return mdev;
 }

drivers/gpu/drm/mgag200/mgag200_g200er.c

···
 		return ERR_PTR(ret);
 
 	drm_mode_config_reset(dev);
+	drm_kms_helper_poll_init(dev);
 
 	return mdev;
 }

drivers/gpu/drm/mgag200/mgag200_g200ev.c

···
 		return ERR_PTR(ret);
 
 	drm_mode_config_reset(dev);
+	drm_kms_helper_poll_init(dev);
 
 	return mdev;
 }

drivers/gpu/drm/mgag200/mgag200_g200ew3.c

···
 		return ERR_PTR(ret);
 
 	drm_mode_config_reset(dev);
+	drm_kms_helper_poll_init(dev);
 
 	return mdev;
 }

drivers/gpu/drm/mgag200/mgag200_g200se.c

···
 		return ERR_PTR(ret);
 
 	drm_mode_config_reset(dev);
+	drm_kms_helper_poll_init(dev);
 
 	return mdev;
 }

drivers/gpu/drm/mgag200/mgag200_g200wb.c

···
 		return ERR_PTR(ret);
 
 	drm_mode_config_reset(dev);
+	drm_kms_helper_poll_init(dev);
 
 	return mdev;
 }

drivers/gpu/drm/mgag200/mgag200_vga.c

···
 };
 
 static const struct drm_connector_helper_funcs mgag200_vga_connector_helper_funcs = {
-	.get_modes = drm_connector_helper_get_modes
+	.get_modes = drm_connector_helper_get_modes,
+	.detect_ctx = drm_connector_helper_detect_from_ddc
 };
 
 static const struct drm_connector_funcs mgag200_vga_connector_funcs = {
···
 		return ret;
 	}
 	drm_connector_helper_add(connector, &mgag200_vga_connector_helper_funcs);
+
+	connector->polled = DRM_CONNECTOR_POLL_CONNECT |
+			    DRM_CONNECTOR_POLL_DISCONNECT;
 
 	ret = drm_connector_attach_encoder(connector, encoder);
 	if (ret) {