On 1/28/21 9:09 AM, Sakari Ailus wrote:
> From: Ezequiel Garcia <ezequiel@xxxxxxxxxxxxx>
>
> Change v4l2_async_notifier_add_fwnode_remote_subdev semantics
> so it allocates the struct v4l2_async_subdev pointer.
>
> This makes the API consistent: the v4l2-async subdevice addition
> functions have now a unified usage model. This model is simpler,
> as it makes v4l2-async responsible for the allocation and release
> of the subdevice descriptor, and no longer something the driver
> has to worry about.
>
> On the user side, the change makes the API simpler for the drivers
> to use and less error-prone.
>
> Signed-off-by: Ezequiel Garcia <ezequiel@xxxxxxxxxxxxx>
> Reviewed-by: Laurent Pinchart <laurent.pinchart@xxxxxxxxxxxxxxxx>
> Signed-off-by: Sakari Ailus <sakari.ailus@xxxxxxxxxxxxxxx>
> ---
> drivers/media/pci/intel/ipu3/ipu3-cio2-main.c | 17 ++--
> drivers/media/platform/omap3isp/isp.c | 79 ++++++++-----------
> .../platform/rockchip/rkisp1/rkisp1-dev.c | 15 ++--
> .../platform/sunxi/sun4i-csi/sun4i_csi.c | 9 ++-
> .../platform/sunxi/sun4i-csi/sun4i_csi.h | 1 -
> drivers/media/platform/video-mux.c | 14 +---
> drivers/media/v4l2-core/v4l2-async.c | 24 +++---
> drivers/staging/media/imx/imx-media-csi.c | 14 +---
> drivers/staging/media/imx/imx6-mipi-csi2.c | 19 ++---
> drivers/staging/media/imx/imx7-media-csi.c | 16 ++--
> drivers/staging/media/imx/imx7-mipi-csis.c | 15 +---
> include/media/v4l2-async.h | 15 ++--
> 12 files changed, 95 insertions(+), 143 deletions(-)
>
> diff --git a/drivers/media/pci/intel/ipu3/ipu3-cio2-main.c b/drivers/media/pci/intel/ipu3/ipu3-cio2-main.c
> index 3515df50f3e7..8fd311fee4e7 100644
> --- a/drivers/media/pci/intel/ipu3/ipu3-cio2-main.c
> +++ b/drivers/media/pci/intel/ipu3/ipu3-cio2-main.c
> @@ -1464,7 +1464,8 @@ static int cio2_parse_firmware(struct cio2_device *cio2)
> struct v4l2_fwnode_endpoint vep = {
> .bus_type = V4L2_MBUS_CSI2_DPHY
> };
> - struct sensor_async_subdev *s_asd = NULL;
> + struct sensor_async_subdev *s_asd;
> + struct v4l2_async_subdev *asd;
> struct fwnode_handle *ep;
>
> ep = fwnode_graph_get_endpoint_by_id(
> @@ -1478,27 +1479,23 @@ static int cio2_parse_firmware(struct cio2_device *cio2)
> if (ret)
> goto err_parse;
>
> - s_asd = kzalloc(sizeof(*s_asd), GFP_KERNEL);
> - if (!s_asd) {
> - ret = -ENOMEM;
> + asd = v4l2_async_notifier_add_fwnode_remote_subdev(
> + &cio2->notifier, ep, sizeof(*s_asd));
> + if (IS_ERR(asd)) {
> + ret = PTR_ERR(asd);
> goto err_parse;
> }
>
> + s_asd = container_of(asd, struct sensor_async_subdev, asd);
> s_asd->csi2.port = vep.base.port;
> s_asd->csi2.lanes = vep.bus.mipi_csi2.num_data_lanes;
>
> - ret = v4l2_async_notifier_add_fwnode_remote_subdev(
> - &cio2->notifier, ep, &s_asd->asd);
> - if (ret)
> - goto err_parse;
> -
> fwnode_handle_put(ep);
>
> continue;
>
> err_parse:
> fwnode_handle_put(ep);
> - kfree(s_asd);
> return ret;
> }
>
> diff --git a/drivers/media/platform/omap3isp/isp.c b/drivers/media/platform/omap3isp/isp.c
> index b1fc4518e275..1311b4996ece 100644
> --- a/drivers/media/platform/omap3isp/isp.c
> +++ b/drivers/media/platform/omap3isp/isp.c
> @@ -2126,21 +2126,6 @@ static void isp_parse_of_csi1_endpoint(struct device *dev,
> buscfg->bus.ccp2.crc = 1;
> }
>
> -static int isp_alloc_isd(struct isp_async_subdev **isd,
> - struct isp_bus_cfg **buscfg)
> -{
> - struct isp_async_subdev *__isd;
> -
> - __isd = kzalloc(sizeof(*__isd), GFP_KERNEL);
> - if (!__isd)
> - return -ENOMEM;
> -
> - *isd = __isd;
> - *buscfg = &__isd->bus;
> -
> - return 0;
> -}
> -
> static struct {
> u32 phy;
> u32 csi2_if;
> @@ -2156,7 +2141,7 @@ static int isp_parse_of_endpoints(struct isp_device *isp)
> {
> struct fwnode_handle *ep;
> struct isp_async_subdev *isd = NULL;
> - struct isp_bus_cfg *buscfg;
> + struct v4l2_async_subdev *asd;
> unsigned int i;
>
> ep = fwnode_graph_get_endpoint_by_id(
> @@ -2174,20 +2159,15 @@ static int isp_parse_of_endpoints(struct isp_device *isp)
> ret = v4l2_fwnode_endpoint_parse(ep, &vep);
>
> if (!ret) {
> - ret = isp_alloc_isd(&isd, &buscfg);
> - if (ret)
> - return ret;
> - }
> -
> - if (!ret) {
> - isp_parse_of_parallel_endpoint(isp->dev, &vep, buscfg);
> - ret = v4l2_async_notifier_add_fwnode_remote_subdev(
> - &isp->notifier, ep, &isd->asd);
> + asd = v4l2_async_notifier_add_fwnode_remote_subdev(
> + &isp->notifier, ep, sizeof(*isd));
> + if (!IS_ERR(asd)) {
> + isd = container_of(asd, struct isp_async_subdev, asd);
> + isp_parse_of_parallel_endpoint(isp->dev, &vep, &isd->bus);
> + }
> }
>
> fwnode_handle_put(ep);
> - if (ret)
> - kfree(isd);
> }
>
> for (i = 0; i < ARRAY_SIZE(isp_bus_interfaces); i++) {
> @@ -2206,15 +2186,8 @@ static int isp_parse_of_endpoints(struct isp_device *isp)
> dev_dbg(isp->dev, "parsing serial interface %u, node %pOF\n", i,
> to_of_node(ep));
>
> - ret = isp_alloc_isd(&isd, &buscfg);
> - if (ret)
> - return ret;
> -
> ret = v4l2_fwnode_endpoint_parse(ep, &vep);
> - if (!ret) {
> - buscfg->interface = isp_bus_interfaces[i].csi2_if;
> - isp_parse_of_csi2_endpoint(isp->dev, &vep, buscfg);
> - } else if (ret == -ENXIO) {
> + if (ret == -ENXIO) {
> vep = (struct v4l2_fwnode_endpoint)
> { .bus_type = V4L2_MBUS_CSI1 };
> ret = v4l2_fwnode_endpoint_parse(ep, &vep);
> @@ -2224,21 +2197,35 @@ static int isp_parse_of_endpoints(struct isp_device *isp)
> { .bus_type = V4L2_MBUS_CCP2 };
> ret = v4l2_fwnode_endpoint_parse(ep, &vep);
> }
> - if (!ret) {
> - buscfg->interface =
> - isp_bus_interfaces[i].csi1_if;
> - isp_parse_of_csi1_endpoint(isp->dev, &vep,
> - buscfg);
> - }
> }
>
> - if (!ret)
> - ret = v4l2_async_notifier_add_fwnode_remote_subdev(
> - &isp->notifier, ep, &isd->asd);
> + if (!ret) {
> + asd = v4l2_async_notifier_add_fwnode_remote_subdev(
> + &isp->notifier, ep, sizeof(*isd));
> +
> + if (!IS_ERR(asd)) {
> + isd = container_of(asd, struct isp_async_subdev, asd);
> +
> + switch (vep.bus_type) {
> + case V4L2_MBUS_CSI2_DPHY:
> + isd->bus.interface =
> + isp_bus_interfaces[i].csi2_if;
> + isp_parse_of_csi2_endpoint(isp->dev, &vep, &isd->bus);
> + break;
> + case V4L2_MBUS_CSI1:
> + case V4L2_MBUS_CCP2:
> + isd->bus.interface =
> + isp_bus_interfaces[i].csi1_if;
> + isp_parse_of_csi1_endpoint(isp->dev, &vep,
> + &isd->bus);
> + break;
> + default:
> + break;
> + }
> + }
> + }
>
> fwnode_handle_put(ep);
> - if (ret)
> - kfree(isd);
> }
>
> return 0;
> diff --git a/drivers/media/platform/rockchip/rkisp1/rkisp1-dev.c b/drivers/media/platform/rockchip/rkisp1/rkisp1-dev.c
> index 68da1eed753d..daa1b6d22436 100644
> --- a/drivers/media/platform/rockchip/rkisp1/rkisp1-dev.c
> +++ b/drivers/media/platform/rockchip/rkisp1/rkisp1-dev.c
> @@ -252,6 +252,7 @@ static int rkisp1_subdev_notifier(struct rkisp1_device *rkisp1)
> .bus_type = V4L2_MBUS_CSI2_DPHY
> };
> struct rkisp1_sensor_async *rk_asd = NULL;
> + struct v4l2_async_subdev *asd;
> struct fwnode_handle *ep;
>
> ep = fwnode_graph_get_endpoint_by_id(dev_fwnode(rkisp1->dev),
> @@ -264,21 +265,18 @@ static int rkisp1_subdev_notifier(struct rkisp1_device *rkisp1)
> if (ret)
> goto err_parse;
>
> - rk_asd = kzalloc(sizeof(*rk_asd), GFP_KERNEL);
> - if (!rk_asd) {
> - ret = -ENOMEM;
> + asd = v4l2_async_notifier_add_fwnode_remote_subdev(ntf, ep,
> + sizeof(*rk_asd));
> + if (IS_ERR(asd)) {
> + ret = PTR_ERR(asd);
> goto err_parse;
> }
>
> + rk_asd = container_of(asd, struct rkisp1_sensor_async, asd);
> rk_asd->mbus_type = vep.bus_type;
> rk_asd->mbus_flags = vep.bus.mipi_csi2.flags;
> rk_asd->lanes = vep.bus.mipi_csi2.num_data_lanes;
>
> - ret = v4l2_async_notifier_add_fwnode_remote_subdev(ntf, ep,
> - &rk_asd->asd);
> - if (ret)
> - goto err_parse;
> -
> dev_dbg(rkisp1->dev, "registered ep id %d with %d lanes\n",
> vep.base.id, rk_asd->lanes);
>
> @@ -289,7 +287,6 @@ static int rkisp1_subdev_notifier(struct rkisp1_device *rkisp1)
> continue;
> err_parse:
> fwnode_handle_put(ep);
> - kfree(rk_asd);
> v4l2_async_notifier_cleanup(ntf);
> return ret;
> }
> diff --git a/drivers/media/platform/sunxi/sun4i-csi/sun4i_csi.c b/drivers/media/platform/sunxi/sun4i-csi/sun4i_csi.c
> index ec46cff80fdb..3f94b8c966f3 100644
> --- a/drivers/media/platform/sunxi/sun4i-csi/sun4i_csi.c
> +++ b/drivers/media/platform/sunxi/sun4i-csi/sun4i_csi.c
> @@ -118,6 +118,7 @@ static int sun4i_csi_notifier_init(struct sun4i_csi *csi)
> struct v4l2_fwnode_endpoint vep = {
> .bus_type = V4L2_MBUS_PARALLEL,
> };
> + struct v4l2_async_subdev *asd;
> struct fwnode_handle *ep;
> int ret;
>
> @@ -134,10 +135,12 @@ static int sun4i_csi_notifier_init(struct sun4i_csi *csi)
>
> csi->bus = vep.bus.parallel;
>
> - ret = v4l2_async_notifier_add_fwnode_remote_subdev(&csi->notifier,
> - ep, &csi->asd);
> - if (ret)
> + asd = v4l2_async_notifier_add_fwnode_remote_subdev(&csi->notifier,
> + ep, sizeof(*asd));
> + if (IS_ERR(asd)) {
> + ret = PTR_ERR(asd);
> goto out;
> + }
>
> csi->notifier.ops = &sun4i_csi_notify_ops;
>
> diff --git a/drivers/media/platform/sunxi/sun4i-csi/sun4i_csi.h b/drivers/media/platform/sunxi/sun4i-csi/sun4i_csi.h
> index 0f67ff652c2e..a5f61ee0ec4d 100644
> --- a/drivers/media/platform/sunxi/sun4i-csi/sun4i_csi.h
> +++ b/drivers/media/platform/sunxi/sun4i-csi/sun4i_csi.h
> @@ -139,7 +139,6 @@ struct sun4i_csi {
> struct v4l2_mbus_framefmt subdev_fmt;
>
> /* V4L2 Async variables */
> - struct v4l2_async_subdev asd;
> struct v4l2_async_notifier notifier;
> struct v4l2_subdev *src_subdev;
> int src_pad;
> diff --git a/drivers/media/platform/video-mux.c b/drivers/media/platform/video-mux.c
> index 53570250a25d..7b280dfca727 100644
> --- a/drivers/media/platform/video-mux.c
> +++ b/drivers/media/platform/video-mux.c
> @@ -370,19 +370,13 @@ static int video_mux_async_register(struct video_mux *vmux,
> if (!ep)
> continue;
>
> - asd = kzalloc(sizeof(*asd), GFP_KERNEL);
> - if (!asd) {
> - fwnode_handle_put(ep);
> - return -ENOMEM;
> - }
> -
> - ret = v4l2_async_notifier_add_fwnode_remote_subdev(
> - &vmux->notifier, ep, asd);
> + asd = v4l2_async_notifier_add_fwnode_remote_subdev(
> + &vmux->notifier, ep, sizeof(*asd));
>
> fwnode_handle_put(ep);
>
> - if (ret) {
> - kfree(asd);
> + if (IS_ERR(asd)) {
> + ret = PTR_ERR(asd);
> /* OK if asd already exists */
> if (ret != -EEXIST)
> return ret;
> diff --git a/drivers/media/v4l2-core/v4l2-async.c b/drivers/media/v4l2-core/v4l2-async.c
> index 221feb9a8f7b..ed603ae63cad 100644
> --- a/drivers/media/v4l2-core/v4l2-async.c
> +++ b/drivers/media/v4l2-core/v4l2-async.c
> @@ -656,26 +656,26 @@ v4l2_async_notifier_add_fwnode_subdev(struct v4l2_async_notifier *notifier,
> }
> EXPORT_SYMBOL_GPL(v4l2_async_notifier_add_fwnode_subdev);
>
> -int
> +struct v4l2_async_subdev *
> v4l2_async_notifier_add_fwnode_remote_subdev(struct v4l2_async_notifier *notif,
> struct fwnode_handle *endpoint,
> - struct v4l2_async_subdev *asd)
> + unsigned int asd_struct_size)
> {
> + struct v4l2_async_subdev *asd;
> struct fwnode_handle *remote;
> - int ret;
>
> remote = fwnode_graph_get_remote_port_parent(endpoint);
> if (!remote)
> - return -ENOTCONN;
> + return ERR_PTR(-ENOTCONN);
>
> - asd->match_type = V4L2_ASYNC_MATCH_FWNODE;
> - asd->match.fwnode = remote;
> -
> - ret = v4l2_async_notifier_add_subdev(notif, asd);
> - if (ret)
> - fwnode_handle_put(remote);
> -
> - return ret;
> + asd = v4l2_async_notifier_add_fwnode_subdev(notif, remote,
> + asd_struct_size);
> + /*
> + * Calling v4l2_async_notifier_add_fwnode_subdev grabs a refcount,
> + * so drop the one we got in fwnode_graph_get_remote_port_parent.
> + */
> + fwnode_handle_put(remote);
> + return asd;
> }
> EXPORT_SYMBOL_GPL(v4l2_async_notifier_add_fwnode_remote_subdev);
>
> diff --git a/drivers/staging/media/imx/imx-media-csi.c b/drivers/staging/media/imx/imx-media-csi.c
> index db77fef07654..6344389e6afa 100644
> --- a/drivers/staging/media/imx/imx-media-csi.c
> +++ b/drivers/staging/media/imx/imx-media-csi.c
> @@ -1922,19 +1922,13 @@ static int imx_csi_async_register(struct csi_priv *priv)
> port, 0,
> FWNODE_GRAPH_ENDPOINT_NEXT);
> if (ep) {
> - asd = kzalloc(sizeof(*asd), GFP_KERNEL);
> - if (!asd) {
> - fwnode_handle_put(ep);
> - return -ENOMEM;
> - }
> -
> - ret = v4l2_async_notifier_add_fwnode_remote_subdev(
> - &priv->notifier, ep, asd);
> + asd = v4l2_async_notifier_add_fwnode_remote_subdev(
> + &priv->notifier, ep, sizeof(*asd));
>
> fwnode_handle_put(ep);
>
> - if (ret) {
> - kfree(asd);
> + if (IS_ERR(asd)) {
> + ret = PTR_ERR(asd);
> /* OK if asd already exists */
> if (ret != -EEXIST)
> return ret;
> diff --git a/drivers/staging/media/imx/imx6-mipi-csi2.c b/drivers/staging/media/imx/imx6-mipi-csi2.c
> index 6b58899dcefe..a79ab38158e2 100644
> --- a/drivers/staging/media/imx/imx6-mipi-csi2.c
> +++ b/drivers/staging/media/imx/imx6-mipi-csi2.c
> @@ -641,7 +641,7 @@ static int csi2_async_register(struct csi2_dev *csi2)
> struct v4l2_fwnode_endpoint vep = {
> .bus_type = V4L2_MBUS_CSI2_DPHY,
> };
> - struct v4l2_async_subdev *asd = NULL;
> + struct v4l2_async_subdev *asd;
> struct fwnode_handle *ep;
> int ret;
>
> @@ -661,19 +661,13 @@ static int csi2_async_register(struct csi2_dev *csi2)
> dev_dbg(csi2->dev, "data lanes: %d\n", vep.bus.mipi_csi2.num_data_lanes);
> dev_dbg(csi2->dev, "flags: 0x%08x\n", vep.bus.mipi_csi2.flags);
>
> - asd = kzalloc(sizeof(*asd), GFP_KERNEL);
> - if (!asd) {
> - ret = -ENOMEM;
> - goto err_parse;
> - }
> -
> - ret = v4l2_async_notifier_add_fwnode_remote_subdev(
> - &csi2->notifier, ep, asd);
> - if (ret)
> - goto err_parse;
> -
> + asd = v4l2_async_notifier_add_fwnode_remote_subdev(
> + &csi2->notifier, ep, sizeof(*asd));
> fwnode_handle_put(ep);
>
> + if (IS_ERR(asd))
> + return PTR_ERR(asd);
> +
> csi2->notifier.ops = &csi2_notify_ops;
>
> ret = v4l2_async_subdev_notifier_register(&csi2->sd,
> @@ -685,7 +679,6 @@ static int csi2_async_register(struct csi2_dev *csi2)
>
> err_parse:
> fwnode_handle_put(ep);
> - kfree(asd);
> return ret;
> }
>
> diff --git a/drivers/staging/media/imx/imx7-media-csi.c b/drivers/staging/media/imx/imx7-media-csi.c
> index ac52b1daf991..6c59485291ca 100644
> --- a/drivers/staging/media/imx/imx7-media-csi.c
> +++ b/drivers/staging/media/imx/imx7-media-csi.c
> @@ -1191,7 +1191,7 @@ static const struct v4l2_async_notifier_operations imx7_csi_notify_ops = {
>
> static int imx7_csi_async_register(struct imx7_csi *csi)
> {
> - struct v4l2_async_subdev *asd = NULL;
> + struct v4l2_async_subdev *asd;
> struct fwnode_handle *ep;
> int ret;
>
> @@ -1200,19 +1200,13 @@ static int imx7_csi_async_register(struct imx7_csi *csi)
> ep = fwnode_graph_get_endpoint_by_id(dev_fwnode(csi->dev), 0, 0,
> FWNODE_GRAPH_ENDPOINT_NEXT);
> if (ep) {
> - asd = kzalloc(sizeof(*asd), GFP_KERNEL);
> - if (!asd) {
> - fwnode_handle_put(ep);
> - return -ENOMEM;
> - }
> -
> - ret = v4l2_async_notifier_add_fwnode_remote_subdev(
> - &csi->notifier, ep, asd);
> + asd = v4l2_async_notifier_add_fwnode_remote_subdev(
> + &csi->notifier, ep, sizeof(*asd));
>
> fwnode_handle_put(ep);
>
> - if (ret) {
> - kfree(asd);
> + if (IS_ERR(asd)) {
> + ret = PTR_ERR(asd);
> /* OK if asd already exists */
> if (ret != -EEXIST)
> return ret;
> diff --git a/drivers/staging/media/imx/imx7-mipi-csis.c b/drivers/staging/media/imx/imx7-mipi-csis.c
> index 7612993cc1d6..32d8e7a824d4 100644
> --- a/drivers/staging/media/imx/imx7-mipi-csis.c
> +++ b/drivers/staging/media/imx/imx7-mipi-csis.c
> @@ -1004,7 +1004,7 @@ static int mipi_csis_async_register(struct csi_state *state)
> struct v4l2_fwnode_endpoint vep = {
> .bus_type = V4L2_MBUS_CSI2_DPHY,
> };
> - struct v4l2_async_subdev *asd = NULL;
> + struct v4l2_async_subdev *asd;
> struct fwnode_handle *ep;
> int ret;
>
> @@ -1024,15 +1024,9 @@ static int mipi_csis_async_register(struct csi_state *state)
> dev_dbg(state->dev, "data lanes: %d\n", state->bus.num_data_lanes);
> dev_dbg(state->dev, "flags: 0x%08x\n", state->bus.flags);
>
> - asd = kzalloc(sizeof(*asd), GFP_KERNEL);
> - if (!asd) {
> - ret = -ENOMEM;
> - goto err_parse;
> - }
> -
> - ret = v4l2_async_notifier_add_fwnode_remote_subdev(
> - &state->notifier, ep, asd);
> - if (ret)
> + asd = v4l2_async_notifier_add_fwnode_remote_subdev(
> + &state->notifier, ep, sizeof(*asd));
> + if (IS_ERR(asd))
> goto err_parse;
Missing ret = PTR_ERR(asd); here
With this change:
Reviewed-by: Helen Koike <helen.koike@xxxxxxxxxxxxx>
Thanks
Helen
>
> fwnode_handle_put(ep);
> @@ -1048,7 +1042,6 @@ static int mipi_csis_async_register(struct csi_state *state)
>
> err_parse:
> fwnode_handle_put(ep);
> - kfree(asd);
>
> return ret;
> }
> diff --git a/include/media/v4l2-async.h b/include/media/v4l2-async.h
> index 0ddc06e36c08..8815e233677e 100644
> --- a/include/media/v4l2-async.h
> +++ b/include/media/v4l2-async.h
> @@ -174,9 +174,11 @@ v4l2_async_notifier_add_fwnode_subdev(struct v4l2_async_notifier *notifier,
> *
> * @notif: pointer to &struct v4l2_async_notifier
> * @endpoint: local endpoint pointing to the remote sub-device to be matched
> - * @asd: Async sub-device struct allocated by the caller. The &struct
> - * v4l2_async_subdev shall be the first member of the driver's async
> - * sub-device struct, i.e. both begin at the same memory address.
> + * @asd_struct_size: size of the driver's async sub-device struct, including
> + * sizeof(struct v4l2_async_subdev). The &struct
> + * v4l2_async_subdev shall be the first member of
> + * the driver's async sub-device struct, i.e. both
> + * begin at the same memory address.
> *
> * Gets the remote endpoint of a given local endpoint, set it up for fwnode
> * matching and adds the async sub-device to the notifier's @asd_list. The
> @@ -184,13 +186,12 @@ v4l2_async_notifier_add_fwnode_subdev(struct v4l2_async_notifier *notifier,
> * notifier cleanup time.
> *
> * This is just like @v4l2_async_notifier_add_fwnode_subdev, but with the
> - * exception that the fwnode refers to a local endpoint, not the remote one, and
> - * the function relies on the caller to allocate the async sub-device struct.
> + * exception that the fwnode refers to a local endpoint, not the remote one.
> */
> -int
> +struct v4l2_async_subdev *
> v4l2_async_notifier_add_fwnode_remote_subdev(struct v4l2_async_notifier *notif,
> struct fwnode_handle *endpoint,
> - struct v4l2_async_subdev *asd);
> + unsigned int asd_struct_size);
>
> /**
> * v4l2_async_notifier_add_i2c_subdev - Allocate and add an i2c async
>
