| Message ID | 20240516122539.30787-3-sakari.ailus@linux.intel.com |
|---|---|
| State | Superseded |
| Headers | show |
| Series | Use V4L2 mbus config for conveying MEI CSI link frequency | expand |
On Thu, May 16, 2024 at 03:25:37PM GMT, Sakari Ailus wrote: > Add link_freq field to struct v4l2_mbus_config in order to pass the link > frequency to the receiving sub-device. > > Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com> > --- > drivers/media/v4l2-core/v4l2-common.c | 11 ++++++++--- > include/media/v4l2-mediabus.h | 2 ++ > 2 files changed, 10 insertions(+), 3 deletions(-) > > diff --git a/drivers/media/v4l2-core/v4l2-common.c b/drivers/media/v4l2-core/v4l2-common.c > index 01650aed7c30..ff859a340c5d 100644 > --- a/drivers/media/v4l2-core/v4l2-common.c > +++ b/drivers/media/v4l2-core/v4l2-common.c > @@ -506,13 +506,18 @@ EXPORT_SYMBOL_GPL(__v4l2_get_link_freq_ctrl); > s64 __v4l2_get_link_freq_pad(struct media_pad *pad, unsigned int mul, > unsigned int div) > { > + struct v4l2_mbus_config mbus_config = {}; > struct v4l2_subdev *sd; > + int ret; > > sd = media_entity_to_v4l2_subdev(pad->entity); > - if (!sd) > - return -ENODEV; > + ret = v4l2_subdev_call(sd, pad, get_mbus_config, pad->index, > + &mbus_config); > + if (ret < 0 && ret != -ENOIOCTLCMD) > + return ret; Should we do like what we did with endpoint matching ? (let alone the fact we then backtracked on that.. :) WARN to encourage tx drivers to implement get_mbus_config and advertise the link freq through it ? > > - return __v4l2_get_link_freq_ctrl(sd->ctrl_handler, mul, div); > + return mbus_config.link_freq ?: > + __v4l2_get_link_freq_ctrl(sd->ctrl_handler, mul, div); > } > EXPORT_SYMBOL_GPL(__v4l2_get_link_freq_pad); > #endif /* CONFIG_MEDIA_CONTROLLER */ > diff --git a/include/media/v4l2-mediabus.h b/include/media/v4l2-mediabus.h > index 5bce6e423e94..cc5f776dc662 100644 > --- a/include/media/v4l2-mediabus.h > +++ b/include/media/v4l2-mediabus.h > @@ -148,6 +148,7 @@ enum v4l2_mbus_type { > /** > * struct v4l2_mbus_config - media bus configuration > * @type: interface type > + * @link_freq: The link frequency. See also V4L2_CID_LINK_FREQ control. > * @bus: bus configuration data structure > * @bus.parallel: embedded &struct v4l2_mbus_config_parallel. > * Used if the bus is parallel or BT.656. > @@ -162,6 +163,7 @@ enum v4l2_mbus_type { > */ > struct v4l2_mbus_config { > enum v4l2_mbus_type type; > + u64 link_freq; I will retaliate that link_freq has different meaning for serial and parallel busses, and it would feel more natural having something like mipi_csi2.link_freq parallel.pixel_clock or do you think it's an overkill ? > union { > struct v4l2_mbus_config_parallel parallel; > struct v4l2_mbus_config_mipi_csi1 mipi_csi1; > -- > 2.39.2 >
Hi Sakari On Tue, May 28, 2024 at 06:09:12AM GMT, Sakari Ailus wrote: > Hi Jacopo, > > On Fri, May 17, 2024 at 12:31:43PM +0200, Jacopo Mondi wrote: > > On Thu, May 16, 2024 at 03:25:37PM GMT, Sakari Ailus wrote: > > > Add link_freq field to struct v4l2_mbus_config in order to pass the link > > > frequency to the receiving sub-device. > > > > > > Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com> > > > --- > > > drivers/media/v4l2-core/v4l2-common.c | 11 ++++++++--- > > > include/media/v4l2-mediabus.h | 2 ++ > > > 2 files changed, 10 insertions(+), 3 deletions(-) > > > > > > diff --git a/drivers/media/v4l2-core/v4l2-common.c b/drivers/media/v4l2-core/v4l2-common.c > > > index 01650aed7c30..ff859a340c5d 100644 > > > --- a/drivers/media/v4l2-core/v4l2-common.c > > > +++ b/drivers/media/v4l2-core/v4l2-common.c > > > @@ -506,13 +506,18 @@ EXPORT_SYMBOL_GPL(__v4l2_get_link_freq_ctrl); > > > s64 __v4l2_get_link_freq_pad(struct media_pad *pad, unsigned int mul, > > > unsigned int div) > > > { > > > + struct v4l2_mbus_config mbus_config = {}; > > > struct v4l2_subdev *sd; > > > + int ret; > > > > > > sd = media_entity_to_v4l2_subdev(pad->entity); > > > - if (!sd) > > > - return -ENODEV; > > > + ret = v4l2_subdev_call(sd, pad, get_mbus_config, pad->index, > > > + &mbus_config); > > > + if (ret < 0 && ret != -ENOIOCTLCMD) > > > + return ret; > > > > Should we do like what we did with endpoint matching ? (let alone the > > fact we then backtracked on that.. :) > > Hmm. What exactly are you suggesting? > See below > > > > WARN to encourage tx drivers to implement get_mbus_config and > > advertise the link freq through it ? > > Why? If the value is conveyed by the control, there's no reason to copy it > here, is it? > My understanding is that using get_mbus_config() is preferred, but yes, if the control is in place the same value should be propagated through both path, which is probably a biy silly, yeah. Ok, ignore the suggestion then > > > > > > > > - return __v4l2_get_link_freq_ctrl(sd->ctrl_handler, mul, div); > > > + return mbus_config.link_freq ?: > > > + __v4l2_get_link_freq_ctrl(sd->ctrl_handler, mul, div); > > > } > > > EXPORT_SYMBOL_GPL(__v4l2_get_link_freq_pad); > > > #endif /* CONFIG_MEDIA_CONTROLLER */ > > > diff --git a/include/media/v4l2-mediabus.h b/include/media/v4l2-mediabus.h > > > index 5bce6e423e94..cc5f776dc662 100644 > > > --- a/include/media/v4l2-mediabus.h > > > +++ b/include/media/v4l2-mediabus.h > > > @@ -148,6 +148,7 @@ enum v4l2_mbus_type { > > > /** > > > * struct v4l2_mbus_config - media bus configuration > > > * @type: interface type > > > + * @link_freq: The link frequency. See also V4L2_CID_LINK_FREQ control. > > > * @bus: bus configuration data structure > > > * @bus.parallel: embedded &struct v4l2_mbus_config_parallel. > > > * Used if the bus is parallel or BT.656. > > > @@ -162,6 +163,7 @@ enum v4l2_mbus_type { > > > */ > > > struct v4l2_mbus_config { > > > enum v4l2_mbus_type type; > > > + u64 link_freq; > > > > I will retaliate that link_freq has different meaning for serial and > > parallel busses, and it would feel more natural having something like > > > > mipi_csi2.link_freq > > parallel.pixel_clock > > > > or do you think it's an overkill ? > > How is the meaning different? The value reflects the frequency on both > buses. The meaning is slightly different. For a parallel bus the "link_freq" is actually the pixel clock (and thus "link_freq" is an ill-defined concept for parallel busses ?). For serial busses there actually is a "link frequency" which corresponds to the clock lane frequency. In general, however we define it, the link_freq is a bus property and feels better placed inside the per-bus structures to me. Up to you > > > > > > union { > > > struct v4l2_mbus_config_parallel parallel; > > > struct v4l2_mbus_config_mipi_csi1 mipi_csi1; > > -- > Kind regards, > > Sakari Ailus
diff --git a/drivers/media/v4l2-core/v4l2-common.c b/drivers/media/v4l2-core/v4l2-common.c index 01650aed7c30..ff859a340c5d 100644 --- a/drivers/media/v4l2-core/v4l2-common.c +++ b/drivers/media/v4l2-core/v4l2-common.c @@ -506,13 +506,18 @@ EXPORT_SYMBOL_GPL(__v4l2_get_link_freq_ctrl); s64 __v4l2_get_link_freq_pad(struct media_pad *pad, unsigned int mul, unsigned int div) { + struct v4l2_mbus_config mbus_config = {}; struct v4l2_subdev *sd; + int ret; sd = media_entity_to_v4l2_subdev(pad->entity); - if (!sd) - return -ENODEV; + ret = v4l2_subdev_call(sd, pad, get_mbus_config, pad->index, + &mbus_config); + if (ret < 0 && ret != -ENOIOCTLCMD) + return ret; - return __v4l2_get_link_freq_ctrl(sd->ctrl_handler, mul, div); + return mbus_config.link_freq ?: + __v4l2_get_link_freq_ctrl(sd->ctrl_handler, mul, div); } EXPORT_SYMBOL_GPL(__v4l2_get_link_freq_pad); #endif /* CONFIG_MEDIA_CONTROLLER */ diff --git a/include/media/v4l2-mediabus.h b/include/media/v4l2-mediabus.h index 5bce6e423e94..cc5f776dc662 100644 --- a/include/media/v4l2-mediabus.h +++ b/include/media/v4l2-mediabus.h @@ -148,6 +148,7 @@ enum v4l2_mbus_type { /** * struct v4l2_mbus_config - media bus configuration * @type: interface type + * @link_freq: The link frequency. See also V4L2_CID_LINK_FREQ control. * @bus: bus configuration data structure * @bus.parallel: embedded &struct v4l2_mbus_config_parallel. * Used if the bus is parallel or BT.656. @@ -162,6 +163,7 @@ enum v4l2_mbus_type { */ struct v4l2_mbus_config { enum v4l2_mbus_type type; + u64 link_freq; union { struct v4l2_mbus_config_parallel parallel; struct v4l2_mbus_config_mipi_csi1 mipi_csi1;
Add link_freq field to struct v4l2_mbus_config in order to pass the link frequency to the receiving sub-device. Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com> --- drivers/media/v4l2-core/v4l2-common.c | 11 ++++++++--- include/media/v4l2-mediabus.h | 2 ++ 2 files changed, 10 insertions(+), 3 deletions(-)