From patchwork Tue Jun 11 08:23:44 2013 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Guennadi Liakhovetski X-Patchwork-Id: 2700801 Return-Path: X-Original-To: patchwork-linux-sh@patchwork.kernel.org Delivered-To: patchwork-process-083081@patchwork1.kernel.org Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by patchwork1.kernel.org (Postfix) with ESMTP id 7F86A40077 for ; Tue, 11 Jun 2013 09:27:38 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753403Ab3FKJ1i (ORCPT ); Tue, 11 Jun 2013 05:27:38 -0400 Received: from moutng.kundenserver.de ([212.227.17.10]:60122 "EHLO moutng.kundenserver.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753185Ab3FKJ1e (ORCPT ); Tue, 11 Jun 2013 05:27:34 -0400 Received: from axis700.grange (dslb-178-001-148-081.pools.arcor-ip.net [178.1.148.81]) by mrelayeu.kundenserver.de (node=mrbap3) with ESMTP (Nemesis) id 0M1GfI-1UWiol34zA-00tDo6; Tue, 11 Jun 2013 11:27:17 +0200 Received: from 6a.grange (unknown [192.168.1.11]) by axis700.grange (Postfix) with ESMTPS id 9F9BF40BD6; Tue, 11 Jun 2013 10:24:05 +0200 (CEST) Received: from lyakh by 6a.grange with local (Exim 4.72) (envelope-from ) id 1UmJs5-0002Bx-2G; Tue, 11 Jun 2013 10:24:05 +0200 From: Guennadi Liakhovetski To: linux-media@vger.kernel.org Cc: Laurent Pinchart , Sylwester Nawrocki , Hans Verkuil , linux-sh@vger.kernel.org, Magnus Damm , Sakari Ailus , Prabhakar Lad , Sascha Hauer , Guennadi Liakhovetski Subject: [PATCH v10 17/21] soc-camera: switch I2C subdevice drivers to use v4l2-clk Date: Tue, 11 Jun 2013 10:23:44 +0200 Message-Id: <1370939028-8352-18-git-send-email-g.liakhovetski@gmx.de> X-Mailer: git-send-email 1.7.2.5 In-Reply-To: <1370939028-8352-1-git-send-email-g.liakhovetski@gmx.de> References: <1370939028-8352-1-git-send-email-g.liakhovetski@gmx.de> X-Provags-ID: V02:K0:Rr2W00qA94Cihj0/aDE+fnBgNvWkrJTbhnPqDphKsc1 ZI6numgiPhlC2qdKx0Q3Q7fJWmJQb9mVdsBH3HNKMhiJ3Tto0p SkjkYFLrd+jmZ8FGEWTF8YdDB3f3BBLIPdMkrvHxuYf57wGUNz fL6HrqR2AVcUZfzGVaMdM5FOqNn+Sl0WE/gLkGZMGJjUukjsKw dGL+eHf3C4MqThsALu9RWHb6C/zywxaBjxxabppM9ErcyI7J7v sJhNM2oMr1fjwZYsdasIIeRN7IXaX7RnGUpj2YgqHjaEuOhpnj QTbYhskUzKZVmfliRhAlWweiUotpaaXmz3Ys+qw3CXftaDkY8T dH6TiFLrtsBhFzqZLWb28dwSqAHRLdWLOK6t4s19ZS6XoQitVe yVM0Ksa+qQ5rA== Sender: linux-sh-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-sh@vger.kernel.org Instead of centrally enabling and disabling subdevice master clocks in soc-camera core, let subdevice drivers do that themselves, using the V4L2 clock API and soc-camera convenience wrappers. Signed-off-by: Guennadi Liakhovetski --- drivers/media/i2c/soc_camera/imx074.c | 18 ++- drivers/media/i2c/soc_camera/mt9m001.c | 17 ++- drivers/media/i2c/soc_camera/mt9m111.c | 20 ++- drivers/media/i2c/soc_camera/mt9t031.c | 19 ++- drivers/media/i2c/soc_camera/mt9t112.c | 25 +++- drivers/media/i2c/soc_camera/mt9v022.c | 17 ++- drivers/media/i2c/soc_camera/ov2640.c | 19 ++- drivers/media/i2c/soc_camera/ov5642.c | 20 ++- drivers/media/i2c/soc_camera/ov6650.c | 17 ++- drivers/media/i2c/soc_camera/ov772x.c | 15 ++- drivers/media/i2c/soc_camera/ov9640.c | 17 ++- drivers/media/i2c/soc_camera/ov9640.h | 1 + drivers/media/i2c/soc_camera/ov9740.c | 18 ++- drivers/media/i2c/soc_camera/rj54n1cb0c.c | 17 ++- drivers/media/i2c/soc_camera/tw9910.c | 24 +++- drivers/media/platform/soc_camera/soc_camera.c | 162 +++++++++++++++----- .../platform/soc_camera/soc_camera_platform.c | 2 +- include/media/soc_camera.h | 13 +- 18 files changed, 362 insertions(+), 79 deletions(-) diff --git a/drivers/media/i2c/soc_camera/imx074.c b/drivers/media/i2c/soc_camera/imx074.c index a2a5cbb..a6a5060 100644 --- a/drivers/media/i2c/soc_camera/imx074.c +++ b/drivers/media/i2c/soc_camera/imx074.c @@ -18,6 +18,7 @@ #include #include +#include #include #include @@ -77,6 +78,7 @@ struct imx074_datafmt { struct imx074 { struct v4l2_subdev subdev; const struct imx074_datafmt *fmt; + struct v4l2_clk *clk; }; static const struct imx074_datafmt imx074_colour_fmts[] = { @@ -272,8 +274,9 @@ static int imx074_s_power(struct v4l2_subdev *sd, int on) { struct i2c_client *client = v4l2_get_subdevdata(sd); struct soc_camera_subdev_desc *ssdd = soc_camera_i2c_to_desc(client); + struct imx074 *priv = to_imx074(client); - return soc_camera_set_power(&client->dev, ssdd, on); + return soc_camera_set_power(&client->dev, ssdd, priv->clk, on); } static int imx074_g_mbus_config(struct v4l2_subdev *sd, @@ -431,6 +434,7 @@ static int imx074_probe(struct i2c_client *client, struct imx074 *priv; struct i2c_adapter *adapter = to_i2c_adapter(client->dev.parent); struct soc_camera_subdev_desc *ssdd = soc_camera_i2c_to_desc(client); + int ret; if (!ssdd) { dev_err(&client->dev, "IMX074: missing platform data!\n"); @@ -451,13 +455,23 @@ static int imx074_probe(struct i2c_client *client, priv->fmt = &imx074_colour_fmts[0]; - return imx074_video_probe(client); + priv->clk = v4l2_clk_get(&client->dev, "mclk"); + if (IS_ERR(priv->clk)) + return PTR_ERR(priv->clk); + + ret = imx074_video_probe(client); + if (ret < 0) + v4l2_clk_put(priv->clk); + + return ret; } static int imx074_remove(struct i2c_client *client) { struct soc_camera_subdev_desc *ssdd = soc_camera_i2c_to_desc(client); + struct imx074 *priv = to_imx074(client); + v4l2_clk_put(priv->clk); if (ssdd->free_bus) ssdd->free_bus(ssdd); diff --git a/drivers/media/i2c/soc_camera/mt9m001.c b/drivers/media/i2c/soc_camera/mt9m001.c index dd90898..620f9df 100644 --- a/drivers/media/i2c/soc_camera/mt9m001.c +++ b/drivers/media/i2c/soc_camera/mt9m001.c @@ -16,6 +16,7 @@ #include #include +#include #include #include #include @@ -94,6 +95,7 @@ struct mt9m001 { struct v4l2_ctrl *exposure; }; struct v4l2_rect rect; /* Sensor window */ + struct v4l2_clk *clk; const struct mt9m001_datafmt *fmt; const struct mt9m001_datafmt *fmts; int num_fmts; @@ -381,8 +383,9 @@ static int mt9m001_s_power(struct v4l2_subdev *sd, int on) { struct i2c_client *client = v4l2_get_subdevdata(sd); struct soc_camera_subdev_desc *ssdd = soc_camera_i2c_to_desc(client); + struct mt9m001 *mt9m001 = to_mt9m001(client); - return soc_camera_set_power(&client->dev, ssdd, on); + return soc_camera_set_power(&client->dev, ssdd, mt9m001->clk, on); } static int mt9m001_g_volatile_ctrl(struct v4l2_ctrl *ctrl) @@ -710,9 +713,18 @@ static int mt9m001_probe(struct i2c_client *client, mt9m001->rect.width = MT9M001_MAX_WIDTH; mt9m001->rect.height = MT9M001_MAX_HEIGHT; + mt9m001->clk = v4l2_clk_get(&client->dev, "mclk"); + if (IS_ERR(mt9m001->clk)) { + ret = PTR_ERR(mt9m001->clk); + goto eclkget; + } + ret = mt9m001_video_probe(ssdd, client); - if (ret) + if (ret) { + v4l2_clk_put(mt9m001->clk); +eclkget: v4l2_ctrl_handler_free(&mt9m001->hdl); + } return ret; } @@ -722,6 +734,7 @@ static int mt9m001_remove(struct i2c_client *client) struct mt9m001 *mt9m001 = to_mt9m001(client); struct soc_camera_subdev_desc *ssdd = soc_camera_i2c_to_desc(client); + v4l2_clk_put(mt9m001->clk); v4l2_device_unregister_subdev(&mt9m001->subdev); v4l2_ctrl_handler_free(&mt9m001->hdl); mt9m001_video_remove(ssdd); diff --git a/drivers/media/i2c/soc_camera/mt9m111.c b/drivers/media/i2c/soc_camera/mt9m111.c index 8bd4e0d..5fa9372 100644 --- a/drivers/media/i2c/soc_camera/mt9m111.c +++ b/drivers/media/i2c/soc_camera/mt9m111.c @@ -17,6 +17,7 @@ #include #include +#include #include #include #include @@ -209,6 +210,7 @@ struct mt9m111 { * from v4l2-chip-ident.h */ struct mt9m111_context *ctx; struct v4l2_rect rect; /* cropping rectangle */ + struct v4l2_clk *clk; int width; /* output */ int height; /* sizes */ struct mutex power_lock; /* lock to protect power_count */ @@ -801,14 +803,14 @@ static int mt9m111_power_on(struct mt9m111 *mt9m111) struct soc_camera_subdev_desc *ssdd = soc_camera_i2c_to_desc(client); int ret; - ret = soc_camera_power_on(&client->dev, ssdd); + ret = soc_camera_power_on(&client->dev, ssdd, mt9m111->clk); if (ret < 0) return ret; ret = mt9m111_resume(mt9m111); if (ret < 0) { dev_err(&client->dev, "Failed to resume the sensor: %d\n", ret); - soc_camera_power_off(&client->dev, ssdd); + soc_camera_power_off(&client->dev, ssdd, mt9m111->clk); } return ret; @@ -820,7 +822,7 @@ static void mt9m111_power_off(struct mt9m111 *mt9m111) struct soc_camera_subdev_desc *ssdd = soc_camera_i2c_to_desc(client); mt9m111_suspend(mt9m111); - soc_camera_power_off(&client->dev, ssdd); + soc_camera_power_off(&client->dev, ssdd, mt9m111->clk); } static int mt9m111_s_power(struct v4l2_subdev *sd, int on) @@ -1002,9 +1004,18 @@ static int mt9m111_probe(struct i2c_client *client, mt9m111->lastpage = -1; mutex_init(&mt9m111->power_lock); + mt9m111->clk = v4l2_clk_get(&client->dev, "mclk"); + if (IS_ERR(mt9m111->clk)) { + ret = PTR_ERR(mt9m111->clk); + goto eclkget; + } + ret = mt9m111_video_probe(client); - if (ret) + if (ret) { + v4l2_clk_put(mt9m111->clk); +eclkget: v4l2_ctrl_handler_free(&mt9m111->hdl); + } return ret; } @@ -1013,6 +1024,7 @@ static int mt9m111_remove(struct i2c_client *client) { struct mt9m111 *mt9m111 = to_mt9m111(client); + v4l2_clk_put(mt9m111->clk); v4l2_device_unregister_subdev(&mt9m111->subdev); v4l2_ctrl_handler_free(&mt9m111->hdl); diff --git a/drivers/media/i2c/soc_camera/mt9t031.c b/drivers/media/i2c/soc_camera/mt9t031.c index 191e3f1..1740f43 100644 --- a/drivers/media/i2c/soc_camera/mt9t031.c +++ b/drivers/media/i2c/soc_camera/mt9t031.c @@ -19,6 +19,7 @@ #include #include +#include #include #include @@ -76,6 +77,7 @@ struct mt9t031 { struct v4l2_ctrl *exposure; }; struct v4l2_rect rect; /* Sensor window */ + struct v4l2_clk *clk; int model; /* V4L2_IDENT_MT9T031* codes from v4l2-chip-ident.h */ u16 xskip; u16 yskip; @@ -610,16 +612,17 @@ static int mt9t031_s_power(struct v4l2_subdev *sd, int on) struct i2c_client *client = v4l2_get_subdevdata(sd); struct soc_camera_subdev_desc *ssdd = soc_camera_i2c_to_desc(client); struct video_device *vdev = soc_camera_i2c_to_vdev(client); + struct mt9t031 *mt9t031 = to_mt9t031(client); int ret; if (on) { - ret = soc_camera_power_on(&client->dev, ssdd); + ret = soc_camera_power_on(&client->dev, ssdd, mt9t031->clk); if (ret < 0) return ret; vdev->dev.type = &mt9t031_dev_type; } else { vdev->dev.type = NULL; - soc_camera_power_off(&client->dev, ssdd); + soc_camera_power_off(&client->dev, ssdd, mt9t031->clk); } return 0; @@ -812,9 +815,18 @@ static int mt9t031_probe(struct i2c_client *client, mt9t031->xskip = 1; mt9t031->yskip = 1; + mt9t031->clk = v4l2_clk_get(&client->dev, "mclk"); + if (IS_ERR(mt9t031->clk)) { + ret = PTR_ERR(mt9t031->clk); + goto eclkget; + } + ret = mt9t031_video_probe(client); - if (ret) + if (ret) { + v4l2_clk_put(mt9t031->clk); +eclkget: v4l2_ctrl_handler_free(&mt9t031->hdl); + } return ret; } @@ -823,6 +835,7 @@ static int mt9t031_remove(struct i2c_client *client) { struct mt9t031 *mt9t031 = to_mt9t031(client); + v4l2_clk_put(mt9t031->clk); v4l2_device_unregister_subdev(&mt9t031->subdev); v4l2_ctrl_handler_free(&mt9t031->hdl); diff --git a/drivers/media/i2c/soc_camera/mt9t112.c b/drivers/media/i2c/soc_camera/mt9t112.c index 0af29a4..577cdea 100644 --- a/drivers/media/i2c/soc_camera/mt9t112.c +++ b/drivers/media/i2c/soc_camera/mt9t112.c @@ -28,6 +28,7 @@ #include #include #include +#include #include /* you can check PLL/clock info */ @@ -90,6 +91,7 @@ struct mt9t112_priv { struct mt9t112_camera_info *info; struct i2c_client *client; struct v4l2_rect frame; + struct v4l2_clk *clk; const struct mt9t112_format *format; int model; int num_formats; @@ -781,8 +783,9 @@ static int mt9t112_s_power(struct v4l2_subdev *sd, int on) { struct i2c_client *client = v4l2_get_subdevdata(sd); struct soc_camera_subdev_desc *ssdd = soc_camera_i2c_to_desc(client); + struct mt9t112_priv *priv = to_mt9t112(client); - return soc_camera_set_power(&client->dev, ssdd, on); + return soc_camera_set_power(&client->dev, ssdd, priv->clk, on); } static struct v4l2_subdev_core_ops mt9t112_subdev_core_ops = { @@ -1108,16 +1111,29 @@ static int mt9t112_probe(struct i2c_client *client, v4l2_i2c_subdev_init(&priv->subdev, client, &mt9t112_subdev_ops); + priv->clk = v4l2_clk_get(&client->dev, "mclk"); + if (IS_ERR(priv->clk)) + return PTR_ERR(priv->clk); + ret = mt9t112_camera_probe(client); - if (ret) - return ret; /* Cannot fail: using the default supported pixel code */ - mt9t112_set_params(priv, &rect, V4L2_MBUS_FMT_UYVY8_2X8); + if (!ret) + mt9t112_set_params(priv, &rect, V4L2_MBUS_FMT_UYVY8_2X8); + else + v4l2_clk_put(priv->clk); return ret; } +static int mt9t112_remove(struct i2c_client *client) +{ + struct mt9t112_priv *priv = to_mt9t112(client); + + v4l2_clk_put(priv->clk); + return 0; +} + static const struct i2c_device_id mt9t112_id[] = { { "mt9t112", 0 }, { } @@ -1129,6 +1145,7 @@ static struct i2c_driver mt9t112_i2c_driver = { .name = "mt9t112", }, .probe = mt9t112_probe, + .remove = mt9t112_remove, .id_table = mt9t112_id, }; diff --git a/drivers/media/i2c/soc_camera/mt9v022.c b/drivers/media/i2c/soc_camera/mt9v022.c index a295e59..3164f56 100644 --- a/drivers/media/i2c/soc_camera/mt9v022.c +++ b/drivers/media/i2c/soc_camera/mt9v022.c @@ -20,6 +20,7 @@ #include #include #include +#include #include /* @@ -149,6 +150,7 @@ struct mt9v022 { struct v4l2_ctrl *hblank; struct v4l2_ctrl *vblank; struct v4l2_rect rect; /* Sensor window */ + struct v4l2_clk *clk; const struct mt9v022_datafmt *fmt; const struct mt9v022_datafmt *fmts; const struct mt9v02x_register *reg; @@ -518,8 +520,9 @@ static int mt9v022_s_power(struct v4l2_subdev *sd, int on) { struct i2c_client *client = v4l2_get_subdevdata(sd); struct soc_camera_subdev_desc *ssdd = soc_camera_i2c_to_desc(client); + struct mt9v022 *mt9v022 = to_mt9v022(client); - return soc_camera_set_power(&client->dev, ssdd, on); + return soc_camera_set_power(&client->dev, ssdd, mt9v022->clk, on); } static int mt9v022_g_volatile_ctrl(struct v4l2_ctrl *ctrl) @@ -957,9 +960,18 @@ static int mt9v022_probe(struct i2c_client *client, mt9v022->rect.width = MT9V022_MAX_WIDTH; mt9v022->rect.height = MT9V022_MAX_HEIGHT; + mt9v022->clk = v4l2_clk_get(&client->dev, "mclk"); + if (IS_ERR(mt9v022->clk)) { + ret = PTR_ERR(mt9v022->clk); + goto eclkget; + } + ret = mt9v022_video_probe(client); - if (ret) + if (ret) { + v4l2_clk_put(mt9v022->clk); +eclkget: v4l2_ctrl_handler_free(&mt9v022->hdl); + } return ret; } @@ -969,6 +981,7 @@ static int mt9v022_remove(struct i2c_client *client) struct mt9v022 *mt9v022 = to_mt9v022(client); struct soc_camera_subdev_desc *ssdd = soc_camera_i2c_to_desc(client); + v4l2_clk_put(mt9v022->clk); v4l2_device_unregister_subdev(&mt9v022->subdev); if (ssdd->free_bus) ssdd->free_bus(ssdd); diff --git a/drivers/media/i2c/soc_camera/ov2640.c b/drivers/media/i2c/soc_camera/ov2640.c index e316842..0c97b8c 100644 --- a/drivers/media/i2c/soc_camera/ov2640.c +++ b/drivers/media/i2c/soc_camera/ov2640.c @@ -23,6 +23,7 @@ #include #include +#include #include #include @@ -303,6 +304,7 @@ struct ov2640_priv { struct v4l2_subdev subdev; struct v4l2_ctrl_handler hdl; enum v4l2_mbus_pixelcode cfmt_code; + struct v4l2_clk *clk; const struct ov2640_win_size *win; int model; }; @@ -772,8 +774,9 @@ static int ov2640_s_power(struct v4l2_subdev *sd, int on) { struct i2c_client *client = v4l2_get_subdevdata(sd); struct soc_camera_subdev_desc *ssdd = soc_camera_i2c_to_desc(client); + struct ov2640_priv *priv = to_ov2640(client); - return soc_camera_set_power(&client->dev, ssdd, on); + return soc_camera_set_power(&client->dev, ssdd, priv->clk, on); } /* Select the nearest higher resolution for capture */ @@ -1113,11 +1116,20 @@ static int ov2640_probe(struct i2c_client *client, if (priv->hdl.error) return priv->hdl.error; + priv->clk = v4l2_clk_get(&client->dev, "mclk"); + if (IS_ERR(priv->clk)) { + ret = PTR_ERR(priv->clk); + goto eclkget; + } + ret = ov2640_video_probe(client); - if (ret) + if (ret) { + v4l2_clk_put(priv->clk); +eclkget: v4l2_ctrl_handler_free(&priv->hdl); - else + } else { dev_info(&adapter->dev, "OV2640 Probed\n"); + } return ret; } @@ -1126,6 +1138,7 @@ static int ov2640_remove(struct i2c_client *client) { struct ov2640_priv *priv = to_ov2640(client); + v4l2_clk_put(priv->clk); v4l2_device_unregister_subdev(&priv->subdev); v4l2_ctrl_handler_free(&priv->hdl); return 0; diff --git a/drivers/media/i2c/soc_camera/ov5642.c b/drivers/media/i2c/soc_camera/ov5642.c index 9aa56de..8ffc8f9 100644 --- a/drivers/media/i2c/soc_camera/ov5642.c +++ b/drivers/media/i2c/soc_camera/ov5642.c @@ -25,6 +25,7 @@ #include #include +#include #include /* OV5642 registers */ @@ -610,6 +611,7 @@ struct ov5642 { struct v4l2_subdev subdev; const struct ov5642_datafmt *fmt; struct v4l2_rect crop_rect; + struct v4l2_clk *clk; /* blanking information */ int total_width; @@ -935,12 +937,13 @@ static int ov5642_s_power(struct v4l2_subdev *sd, int on) { struct i2c_client *client = v4l2_get_subdevdata(sd); struct soc_camera_subdev_desc *ssdd = soc_camera_i2c_to_desc(client); + struct ov5642 *priv = to_ov5642(client); int ret; if (!on) - return soc_camera_power_off(&client->dev, ssdd); + return soc_camera_power_off(&client->dev, ssdd, priv->clk); - ret = soc_camera_power_on(&client->dev, ssdd); + ret = soc_camera_power_on(&client->dev, ssdd, priv->clk); if (ret < 0) return ret; @@ -1021,6 +1024,7 @@ static int ov5642_probe(struct i2c_client *client, { struct ov5642 *priv; struct soc_camera_subdev_desc *ssdd = soc_camera_i2c_to_desc(client); + int ret; if (!ssdd) { dev_err(&client->dev, "OV5642: missing platform data!\n"); @@ -1042,13 +1046,23 @@ static int ov5642_probe(struct i2c_client *client, priv->total_width = OV5642_DEFAULT_WIDTH + BLANKING_EXTRA_WIDTH; priv->total_height = BLANKING_MIN_HEIGHT; - return ov5642_video_probe(client); + priv->clk = v4l2_clk_get(&client->dev, "mclk"); + if (IS_ERR(priv->clk)) + return PTR_ERR(priv->clk); + + ret = ov5642_video_probe(client); + if (ret < 0) + v4l2_clk_put(priv->clk); + + return ret; } static int ov5642_remove(struct i2c_client *client) { struct soc_camera_subdev_desc *ssdd = soc_camera_i2c_to_desc(client); + struct ov5642 *priv = to_ov5642(client); + v4l2_clk_put(priv->clk); if (ssdd->free_bus) ssdd->free_bus(ssdd); diff --git a/drivers/media/i2c/soc_camera/ov6650.c b/drivers/media/i2c/soc_camera/ov6650.c index 991202d..2389aa2 100644 --- a/drivers/media/i2c/soc_camera/ov6650.c +++ b/drivers/media/i2c/soc_camera/ov6650.c @@ -33,6 +33,7 @@ #include #include +#include #include /* Register definitions */ @@ -196,6 +197,7 @@ struct ov6650 { struct v4l2_ctrl *blue; struct v4l2_ctrl *red; }; + struct v4l2_clk *clk; bool half_scale; /* scale down output by 2 */ struct v4l2_rect rect; /* sensor cropping window */ unsigned long pclk_limit; /* from host */ @@ -436,8 +438,9 @@ static int ov6650_s_power(struct v4l2_subdev *sd, int on) { struct i2c_client *client = v4l2_get_subdevdata(sd); struct soc_camera_subdev_desc *ssdd = soc_camera_i2c_to_desc(client); + struct ov6650 *priv = to_ov6650(client); - return soc_camera_set_power(&client->dev, ssdd, on); + return soc_camera_set_power(&client->dev, ssdd, priv->clk, on); } static int ov6650_g_crop(struct v4l2_subdev *sd, struct v4l2_crop *a) @@ -1025,9 +1028,18 @@ static int ov6650_probe(struct i2c_client *client, priv->code = V4L2_MBUS_FMT_YUYV8_2X8; priv->colorspace = V4L2_COLORSPACE_JPEG; + priv->clk = v4l2_clk_get(&client->dev, "mclk"); + if (IS_ERR(priv->clk)) { + ret = PTR_ERR(priv->clk); + goto eclkget; + } + ret = ov6650_video_probe(client); - if (ret) + if (ret) { + v4l2_clk_put(priv->clk); +eclkget: v4l2_ctrl_handler_free(&priv->hdl); + } return ret; } @@ -1036,6 +1048,7 @@ static int ov6650_remove(struct i2c_client *client) { struct ov6650 *priv = to_ov6650(client); + v4l2_clk_put(priv->clk); v4l2_device_unregister_subdev(&priv->subdev); v4l2_ctrl_handler_free(&priv->hdl); return 0; diff --git a/drivers/media/i2c/soc_camera/ov772x.c b/drivers/media/i2c/soc_camera/ov772x.c index 713d62e..d643b69 100644 --- a/drivers/media/i2c/soc_camera/ov772x.c +++ b/drivers/media/i2c/soc_camera/ov772x.c @@ -26,6 +26,7 @@ #include #include +#include #include #include #include @@ -396,6 +397,7 @@ struct ov772x_win_size { struct ov772x_priv { struct v4l2_subdev subdev; struct v4l2_ctrl_handler hdl; + struct v4l2_clk *clk; struct ov772x_camera_info *info; const struct ov772x_color_format *cfmt; const struct ov772x_win_size *win; @@ -668,8 +670,9 @@ static int ov772x_s_power(struct v4l2_subdev *sd, int on) { struct i2c_client *client = v4l2_get_subdevdata(sd); struct soc_camera_subdev_desc *ssdd = soc_camera_i2c_to_desc(client); + struct ov772x_priv *priv = to_ov772x(sd); - return soc_camera_set_power(&client->dev, ssdd, on); + return soc_camera_set_power(&client->dev, ssdd, priv->clk, on); } static const struct ov772x_win_size *ov772x_select_win(u32 width, u32 height) @@ -1088,13 +1091,22 @@ static int ov772x_probe(struct i2c_client *client, if (priv->hdl.error) return priv->hdl.error; + priv->clk = v4l2_clk_get(&client->dev, "mclk"); + if (IS_ERR(priv->clk)) { + ret = PTR_ERR(priv->clk); + goto eclkget; + } + ret = ov772x_video_probe(priv); if (ret < 0) { + v4l2_clk_put(priv->clk); +eclkget: v4l2_ctrl_handler_free(&priv->hdl); } else { priv->cfmt = &ov772x_cfmts[0]; priv->win = &ov772x_win_sizes[0]; } + return ret; } @@ -1102,6 +1114,7 @@ static int ov772x_remove(struct i2c_client *client) { struct ov772x_priv *priv = to_ov772x(i2c_get_clientdata(client)); + v4l2_clk_put(priv->clk); v4l2_device_unregister_subdev(&priv->subdev); v4l2_ctrl_handler_free(&priv->hdl); return 0; diff --git a/drivers/media/i2c/soc_camera/ov9640.c b/drivers/media/i2c/soc_camera/ov9640.c index f4eba1b..681ed7e 100644 --- a/drivers/media/i2c/soc_camera/ov9640.c +++ b/drivers/media/i2c/soc_camera/ov9640.c @@ -29,6 +29,7 @@ #include #include +#include #include #include @@ -337,8 +338,9 @@ static int ov9640_s_power(struct v4l2_subdev *sd, int on) { struct i2c_client *client = v4l2_get_subdevdata(sd); struct soc_camera_subdev_desc *ssdd = soc_camera_i2c_to_desc(client); + struct ov9640_priv *priv = to_ov9640_sensor(sd); - return soc_camera_set_power(&client->dev, ssdd, on); + return soc_camera_set_power(&client->dev, ssdd, priv->clk, on); } /* select nearest higher resolution for capture */ @@ -716,10 +718,18 @@ static int ov9640_probe(struct i2c_client *client, if (priv->hdl.error) return priv->hdl.error; - ret = ov9640_video_probe(client); + priv->clk = v4l2_clk_get(&client->dev, "mclk"); + if (IS_ERR(priv->clk)) { + ret = PTR_ERR(priv->clk); + goto eclkget; + } - if (ret) + ret = ov9640_video_probe(client); + if (ret) { + v4l2_clk_put(priv->clk); +eclkget: v4l2_ctrl_handler_free(&priv->hdl); + } return ret; } @@ -729,6 +739,7 @@ static int ov9640_remove(struct i2c_client *client) struct v4l2_subdev *sd = i2c_get_clientdata(client); struct ov9640_priv *priv = to_ov9640_sensor(sd); + v4l2_clk_put(priv->clk); v4l2_device_unregister_subdev(&priv->subdev); v4l2_ctrl_handler_free(&priv->hdl); return 0; diff --git a/drivers/media/i2c/soc_camera/ov9640.h b/drivers/media/i2c/soc_camera/ov9640.h index 6b33a97..65d13ff 100644 --- a/drivers/media/i2c/soc_camera/ov9640.h +++ b/drivers/media/i2c/soc_camera/ov9640.h @@ -199,6 +199,7 @@ struct ov9640_reg { struct ov9640_priv { struct v4l2_subdev subdev; struct v4l2_ctrl_handler hdl; + struct v4l2_clk *clk; int model; int revision; diff --git a/drivers/media/i2c/soc_camera/ov9740.c b/drivers/media/i2c/soc_camera/ov9740.c index 012bd62..6a5e164 100644 --- a/drivers/media/i2c/soc_camera/ov9740.c +++ b/drivers/media/i2c/soc_camera/ov9740.c @@ -18,6 +18,7 @@ #include #include +#include #include #define to_ov9740(sd) container_of(sd, struct ov9740_priv, subdev) @@ -196,6 +197,7 @@ struct ov9740_reg { struct ov9740_priv { struct v4l2_subdev subdev; struct v4l2_ctrl_handler hdl; + struct v4l2_clk *clk; int ident; u16 model; @@ -792,7 +794,7 @@ static int ov9740_s_power(struct v4l2_subdev *sd, int on) int ret; if (on) { - ret = soc_camera_power_on(&client->dev, ssdd); + ret = soc_camera_power_on(&client->dev, ssdd, priv->clk); if (ret < 0) return ret; @@ -806,7 +808,7 @@ static int ov9740_s_power(struct v4l2_subdev *sd, int on) priv->current_enable = true; } - soc_camera_power_off(&client->dev, ssdd); + soc_camera_power_off(&client->dev, ssdd, priv->clk); } return 0; @@ -975,9 +977,18 @@ static int ov9740_probe(struct i2c_client *client, if (priv->hdl.error) return priv->hdl.error; + priv->clk = v4l2_clk_get(&client->dev, "mclk"); + if (IS_ERR(priv->clk)) { + ret = PTR_ERR(priv->clk); + goto eclkget; + } + ret = ov9740_video_probe(client); - if (ret < 0) + if (ret < 0) { + v4l2_clk_put(priv->clk); +eclkget: v4l2_ctrl_handler_free(&priv->hdl); + } return ret; } @@ -986,6 +997,7 @@ static int ov9740_remove(struct i2c_client *client) { struct ov9740_priv *priv = i2c_get_clientdata(client); + v4l2_clk_put(priv->clk); v4l2_device_unregister_subdev(&priv->subdev); v4l2_ctrl_handler_free(&priv->hdl); return 0; diff --git a/drivers/media/i2c/soc_camera/rj54n1cb0c.c b/drivers/media/i2c/soc_camera/rj54n1cb0c.c index 1f9ec3b..93db388 100644 --- a/drivers/media/i2c/soc_camera/rj54n1cb0c.c +++ b/drivers/media/i2c/soc_camera/rj54n1cb0c.c @@ -17,6 +17,7 @@ #include #include +#include #include #include #include @@ -151,6 +152,7 @@ struct rj54n1_clock_div { struct rj54n1 { struct v4l2_subdev subdev; struct v4l2_ctrl_handler hdl; + struct v4l2_clk *clk; struct rj54n1_clock_div clk_div; const struct rj54n1_datafmt *fmt; struct v4l2_rect rect; /* Sensor window */ @@ -1184,8 +1186,9 @@ static int rj54n1_s_power(struct v4l2_subdev *sd, int on) { struct i2c_client *client = v4l2_get_subdevdata(sd); struct soc_camera_subdev_desc *ssdd = soc_camera_i2c_to_desc(client); + struct rj54n1 *rj54n1 = to_rj54n1(client); - return soc_camera_set_power(&client->dev, ssdd, on); + return soc_camera_set_power(&client->dev, ssdd, rj54n1->clk, on); } static int rj54n1_s_ctrl(struct v4l2_ctrl *ctrl) @@ -1382,9 +1385,18 @@ static int rj54n1_probe(struct i2c_client *client, rj54n1->tgclk_mhz = (rj54n1_priv->mclk_freq / PLL_L * PLL_N) / (clk_div.ratio_tg + 1) / (clk_div.ratio_t + 1); + rj54n1->clk = v4l2_clk_get(&client->dev, "mclk"); + if (IS_ERR(rj54n1->clk)) { + ret = PTR_ERR(rj54n1->clk); + goto eclkget; + } + ret = rj54n1_video_probe(client, rj54n1_priv); - if (ret < 0) + if (ret < 0) { + v4l2_clk_put(rj54n1->clk); +eclkget: v4l2_ctrl_handler_free(&rj54n1->hdl); + } return ret; } @@ -1394,6 +1406,7 @@ static int rj54n1_remove(struct i2c_client *client) struct rj54n1 *rj54n1 = to_rj54n1(client); struct soc_camera_subdev_desc *ssdd = soc_camera_i2c_to_desc(client); + v4l2_clk_put(rj54n1->clk); v4l2_device_unregister_subdev(&rj54n1->subdev); if (ssdd->free_bus) ssdd->free_bus(ssdd); diff --git a/drivers/media/i2c/soc_camera/tw9910.c b/drivers/media/i2c/soc_camera/tw9910.c index 6b9cc2a..fe43591 100644 --- a/drivers/media/i2c/soc_camera/tw9910.c +++ b/drivers/media/i2c/soc_camera/tw9910.c @@ -28,6 +28,7 @@ #include #include #include +#include #include #define GET_ID(val) ((val & 0xF8) >> 3) @@ -228,6 +229,7 @@ struct tw9910_scale_ctrl { struct tw9910_priv { struct v4l2_subdev subdev; + struct v4l2_clk *clk; struct tw9910_video_info *info; const struct tw9910_scale_ctrl *scale; v4l2_std_id norm; @@ -570,8 +572,9 @@ static int tw9910_s_power(struct v4l2_subdev *sd, int on) { struct i2c_client *client = v4l2_get_subdevdata(sd); struct soc_camera_subdev_desc *ssdd = soc_camera_i2c_to_desc(client); + struct tw9910_priv *priv = to_tw9910(client); - return soc_camera_set_power(&client->dev, ssdd, on); + return soc_camera_set_power(&client->dev, ssdd, priv->clk, on); } static int tw9910_set_frame(struct v4l2_subdev *sd, u32 *width, u32 *height) @@ -912,6 +915,7 @@ static int tw9910_probe(struct i2c_client *client, struct i2c_adapter *adapter = to_i2c_adapter(client->dev.parent); struct soc_camera_subdev_desc *ssdd = soc_camera_i2c_to_desc(client); + int ret; if (!ssdd || !ssdd->drv_priv) { dev_err(&client->dev, "TW9910: missing platform data!\n"); @@ -935,7 +939,22 @@ static int tw9910_probe(struct i2c_client *client, v4l2_i2c_subdev_init(&priv->subdev, client, &tw9910_subdev_ops); - return tw9910_video_probe(client); + priv->clk = v4l2_clk_get(&client->dev, "mclk"); + if (IS_ERR(priv->clk)) + return PTR_ERR(priv->clk); + + ret = tw9910_video_probe(client); + if (ret < 0) + v4l2_clk_put(priv->clk); + + return ret; +} + +static int tw9910_remove(struct i2c_client *client) +{ + struct tw9910_priv *priv = to_tw9910(client); + v4l2_clk_put(priv->clk); + return 0; } static const struct i2c_device_id tw9910_id[] = { @@ -949,6 +968,7 @@ static struct i2c_driver tw9910_i2c_driver = { .name = "tw9910", }, .probe = tw9910_probe, + .remove = tw9910_remove, .id_table = tw9910_id, }; diff --git a/drivers/media/platform/soc_camera/soc_camera.c b/drivers/media/platform/soc_camera/soc_camera.c index ac98bcb..5845916 100644 --- a/drivers/media/platform/soc_camera/soc_camera.c +++ b/drivers/media/platform/soc_camera/soc_camera.c @@ -30,6 +30,7 @@ #include #include +#include #include #include #include @@ -50,13 +51,19 @@ static LIST_HEAD(hosts); static LIST_HEAD(devices); static DEFINE_MUTEX(list_lock); /* Protects the list of hosts */ -int soc_camera_power_on(struct device *dev, struct soc_camera_subdev_desc *ssdd) +int soc_camera_power_on(struct device *dev, struct soc_camera_subdev_desc *ssdd, + struct v4l2_clk *clk) { - int ret = regulator_bulk_enable(ssdd->num_regulators, + int ret = clk ? v4l2_clk_enable(clk) : 0; + if (ret < 0) { + dev_err(dev, "Cannot enable clock\n"); + return ret; + } + ret = regulator_bulk_enable(ssdd->num_regulators, ssdd->regulators); if (ret < 0) { dev_err(dev, "Cannot enable regulators\n"); - return ret; + goto eregenable;; } if (ssdd->power) { @@ -64,16 +71,25 @@ int soc_camera_power_on(struct device *dev, struct soc_camera_subdev_desc *ssdd) if (ret < 0) { dev_err(dev, "Platform failed to power-on the camera.\n"); - regulator_bulk_disable(ssdd->num_regulators, - ssdd->regulators); + goto epwron; } } + return 0; + +epwron: + regulator_bulk_disable(ssdd->num_regulators, + ssdd->regulators); +eregenable: + if (clk) + v4l2_clk_disable(clk); + return ret; } EXPORT_SYMBOL(soc_camera_power_on); -int soc_camera_power_off(struct device *dev, struct soc_camera_subdev_desc *ssdd) +int soc_camera_power_off(struct device *dev, struct soc_camera_subdev_desc *ssdd, + struct v4l2_clk *clk) { int ret = 0; int err; @@ -94,6 +110,9 @@ int soc_camera_power_off(struct device *dev, struct soc_camera_subdev_desc *ssdd ret = ret ? : err; } + if (clk) + v4l2_clk_disable(clk); + return ret; } EXPORT_SYMBOL(soc_camera_power_off); @@ -513,9 +532,11 @@ static int soc_camera_add_device(struct soc_camera_device *icd) if (ici->icd) return -EBUSY; - ret = ici->ops->clock_start(ici); - if (ret < 0) - return ret; + if (!icd->clk) { + ret = ici->ops->clock_start(ici); + if (ret < 0) + return ret; + } if (ici->ops->add) { ret = ici->ops->add(icd); @@ -528,7 +549,8 @@ static int soc_camera_add_device(struct soc_camera_device *icd) return 0; eadd: - ici->ops->clock_stop(ici); + if (!icd->clk) + ici->ops->clock_stop(ici); return ret; } @@ -541,7 +563,8 @@ static void soc_camera_remove_device(struct soc_camera_device *icd) if (ici->ops->remove) ici->ops->remove(icd); - ici->ops->clock_stop(ici); + if (!icd->clk) + ici->ops->clock_stop(ici); ici->icd = NULL; } @@ -1124,6 +1147,57 @@ static void scan_add_host(struct soc_camera_host *ici) mutex_unlock(&list_lock); } +/* + * It is invalid to call v4l2_clk_enable() after a successful probing + * asynchronously outside of V4L2 operations, i.e. with .host_lock not held. + */ +static int soc_camera_clk_enable(struct v4l2_clk *clk) +{ + struct soc_camera_device *icd = clk->priv; + struct soc_camera_host *ici; + + if (!icd || !icd->parent) + return -ENODEV; + + ici = to_soc_camera_host(icd->parent); + + if (!try_module_get(ici->ops->owner)) + return -ENODEV; + + /* + * If a different client is currently being probed, the host will tell + * you to go + */ + return ici->ops->clock_start(ici); +} + +static void soc_camera_clk_disable(struct v4l2_clk *clk) +{ + struct soc_camera_device *icd = clk->priv; + struct soc_camera_host *ici; + + if (!icd || !icd->parent) + return; + + ici = to_soc_camera_host(icd->parent); + + ici->ops->clock_stop(ici); + + module_put(ici->ops->owner); +} + +/* + * Eventually, it would be more logical to make the respective host the clock + * owner, but then we would have to copy this struct for each ici. Besides, it + * would introduce the circular dependency problem, unless we port all client + * drivers to release the clock, when not in use. + */ +static const struct v4l2_clk_ops soc_camera_clk_ops = { + .owner = THIS_MODULE, + .enable = soc_camera_clk_enable, + .disable = soc_camera_clk_disable, +}; + #ifdef CONFIG_I2C_BOARDINFO static int soc_camera_init_i2c(struct soc_camera_device *icd, struct soc_camera_desc *sdesc) @@ -1133,19 +1207,32 @@ static int soc_camera_init_i2c(struct soc_camera_device *icd, struct soc_camera_host_desc *shd = &sdesc->host_desc; struct i2c_adapter *adap = i2c_get_adapter(shd->i2c_adapter_id); struct v4l2_subdev *subdev; + char clk_name[V4L2_SUBDEV_NAME_SIZE]; + int ret; if (!adap) { dev_err(icd->pdev, "Cannot get I2C adapter #%d. No driver?\n", shd->i2c_adapter_id); - goto ei2cga; + return -ENODEV; } shd->board_info->platform_data = &sdesc->subdev_desc; + snprintf(clk_name, sizeof(clk_name), "%d-%04x", + shd->i2c_adapter_id, shd->board_info->addr); + + icd->clk = v4l2_clk_register(&soc_camera_clk_ops, clk_name, "mclk", icd); + if (IS_ERR(icd->clk)) { + ret = PTR_ERR(icd->clk); + goto eclkreg; + } + subdev = v4l2_i2c_new_subdev_board(&ici->v4l2_dev, adap, shd->board_info, NULL); - if (!subdev) + if (!subdev) { + ret = -ENODEV; goto ei2cnd; + } client = v4l2_get_subdevdata(subdev); @@ -1154,9 +1241,11 @@ static int soc_camera_init_i2c(struct soc_camera_device *icd, return 0; ei2cnd: + v4l2_clk_unregister(icd->clk); + icd->clk = NULL; +eclkreg: i2c_put_adapter(adap); -ei2cga: - return -ENODEV; + return ret; } static void soc_camera_free_i2c(struct soc_camera_device *icd) @@ -1169,6 +1258,8 @@ static void soc_camera_free_i2c(struct soc_camera_device *icd) v4l2_device_unregister_subdev(i2c_get_clientdata(client)); i2c_unregister_device(client); i2c_put_adapter(adap); + v4l2_clk_unregister(icd->clk); + icd->clk = NULL; } #else #define soc_camera_init_i2c(icd, sdesc) (-ENODEV) @@ -1206,26 +1297,31 @@ static int soc_camera_probe(struct soc_camera_device *icd) if (ssdd->reset) ssdd->reset(icd->pdev); - mutex_lock(&ici->host_lock); - ret = ici->ops->clock_start(ici); - mutex_unlock(&ici->host_lock); - if (ret < 0) - goto eadd; - /* Must have icd->vdev before registering the device */ ret = video_dev_create(icd); if (ret < 0) goto evdc; + /* + * ..._video_start() will create a device node, video_register_device() + * itself is protected against concurrent open() calls, but we also have + * to protect our data also during client probing. + */ + mutex_lock(&ici->host_lock); + /* Non-i2c cameras, e.g., soc_camera_platform, have no board_info */ if (shd->board_info) { ret = soc_camera_init_i2c(icd, sdesc); if (ret < 0) - goto eadddev; + goto eadd; } else if (!shd->add_device || !shd->del_device) { ret = -EINVAL; - goto eadddev; + goto eadd; } else { + ret = ici->ops->clock_start(ici); + if (ret < 0) + goto eadd; + if (shd->module_name) ret = request_module(shd->module_name); @@ -1261,13 +1357,6 @@ static int soc_camera_probe(struct soc_camera_device *icd) icd->field = V4L2_FIELD_ANY; - /* - * ..._video_start() will create a device node, video_register_device() - * itself is protected against concurrent open() calls, but we also have - * to protect our data. - */ - mutex_lock(&ici->host_lock); - ret = soc_camera_video_start(icd); if (ret < 0) goto evidstart; @@ -1280,14 +1369,14 @@ static int soc_camera_probe(struct soc_camera_device *icd) icd->field = mf.field; } - ici->ops->clock_stop(ici); + if (!shd->board_info) + ici->ops->clock_stop(ici); mutex_unlock(&ici->host_lock); return 0; evidstart: - mutex_unlock(&ici->host_lock); soc_camera_free_user_formats(icd); eiufmt: ectrl: @@ -1296,16 +1385,15 @@ ectrl: } else { shd->del_device(icd); module_put(control->driver->owner); - } enodrv: eadddev: + ici->ops->clock_stop(ici); + } +eadd: video_device_release(icd->vdev); icd->vdev = NULL; -evdc: - mutex_lock(&ici->host_lock); - ici->ops->clock_stop(ici); mutex_unlock(&ici->host_lock); -eadd: +evdc: v4l2_ctrl_handler_free(&icd->ctrl_handler); return ret; } diff --git a/drivers/media/platform/soc_camera/soc_camera_platform.c b/drivers/media/platform/soc_camera/soc_camera_platform.c index bdf909d..ceaddfb 100644 --- a/drivers/media/platform/soc_camera/soc_camera_platform.c +++ b/drivers/media/platform/soc_camera/soc_camera_platform.c @@ -54,7 +54,7 @@ static int soc_camera_platform_s_power(struct v4l2_subdev *sd, int on) { struct soc_camera_platform_info *p = v4l2_get_subdevdata(sd); - return soc_camera_set_power(p->icd->control, &p->icd->sdesc->subdev_desc, on); + return soc_camera_set_power(p->icd->control, &p->icd->sdesc->subdev_desc, NULL, on); } static struct v4l2_subdev_core_ops platform_subdev_core_ops = { diff --git a/include/media/soc_camera.h b/include/media/soc_camera.h index 64415ee..f8c1ffe 100644 --- a/include/media/soc_camera.h +++ b/include/media/soc_camera.h @@ -49,6 +49,7 @@ struct soc_camera_device { /* soc_camera.c private count. Only accessed with .host_lock held */ int use_count; struct file *streamer; /* stream owner */ + struct v4l2_clk *clk; union { struct videobuf_queue vb_vidq; struct vb2_queue vb2_vidq; @@ -325,14 +326,16 @@ static inline void soc_camera_limit_side(int *start, int *length, unsigned long soc_camera_apply_board_flags(struct soc_camera_subdev_desc *ssdd, const struct v4l2_mbus_config *cfg); -int soc_camera_power_on(struct device *dev, struct soc_camera_subdev_desc *ssdd); -int soc_camera_power_off(struct device *dev, struct soc_camera_subdev_desc *ssdd); +int soc_camera_power_on(struct device *dev, struct soc_camera_subdev_desc *ssdd, + struct v4l2_clk *clk); +int soc_camera_power_off(struct device *dev, struct soc_camera_subdev_desc *ssdd, + struct v4l2_clk *clk); static inline int soc_camera_set_power(struct device *dev, - struct soc_camera_subdev_desc *ssdd, bool on) + struct soc_camera_subdev_desc *ssdd, struct v4l2_clk *clk, bool on) { - return on ? soc_camera_power_on(dev, ssdd) - : soc_camera_power_off(dev, ssdd); + return on ? soc_camera_power_on(dev, ssdd, clk) + : soc_camera_power_off(dev, ssdd, clk); } /* This is only temporary here - until v4l2-subdev begins to link to video_device */