| Message ID | 1393522540-22887-6-git-send-email-p.zabel@pengutronix.de (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On 02/27/2014 06:35 PM, Philipp Zabel wrote: > This patch adds a new struct of_endpoint which is then embedded in struct > v4l2_of_endpoint and contains the endpoint properties that are not V4L2 > (or even media) specific: the port number, endpoint id, local device tree > node and remote endpoint phandle. of_graph_parse_endpoint parses those > properties and is used by v4l2_of_parse_endpoint, which just adds the > V4L2 MBUS information to the containing v4l2_of_endpoint structure. > > Signed-off-by: Philipp Zabel<p.zabel@pengutronix.de> > --- > Changes since v4: > - Fixed users of struct v4l2_of_endpoint > - Removed left-over #include<media/of_graph.h> from v4l2-of.h > --- > drivers/media/platform/exynos4-is/media-dev.c | 10 ++++----- > drivers/media/platform/exynos4-is/mipi-csis.c | 2 +- > drivers/media/v4l2-core/v4l2-of.c | 16 +++----------- > drivers/of/base.c | 31 +++++++++++++++++++++++++++ > include/linux/of_graph.h | 20 +++++++++++++++++ > include/media/v4l2-of.h | 8 ++----- > 6 files changed, 62 insertions(+), 25 deletions(-) > > diff --git a/drivers/media/platform/exynos4-is/media-dev.c b/drivers/media/platform/exynos4-is/media-dev.c > index d0f82da..04d6ecd 100644 > --- a/drivers/media/platform/exynos4-is/media-dev.c > +++ b/drivers/media/platform/exynos4-is/media-dev.c > @@ -469,10 +469,10 @@ static int fimc_md_parse_port_node(struct fimc_md *fmd, > return 0; > > v4l2_of_parse_endpoint(ep,&endpoint); > - if (WARN_ON(endpoint.port == 0) || index>= FIMC_MAX_SENSORS) > + if (WARN_ON(endpoint.base.port == 0) || index>= FIMC_MAX_SENSORS) > return -EINVAL; > > - pd->mux_id = (endpoint.port - 1)& 0x1; > + pd->mux_id = (endpoint.base.port - 1)& 0x1; > > rem = of_graph_get_remote_port_parent(ep); > of_node_put(ep); > @@ -494,13 +494,13 @@ static int fimc_md_parse_port_node(struct fimc_md *fmd, > return -EINVAL; > } > > - if (fimc_input_is_parallel(endpoint.port)) { > + if (fimc_input_is_parallel(endpoint.base.port)) { > if (endpoint.bus_type == V4L2_MBUS_PARALLEL) > pd->sensor_bus_type = FIMC_BUS_TYPE_ITU_601; > else > pd->sensor_bus_type = FIMC_BUS_TYPE_ITU_656; > pd->flags = endpoint.bus.parallel.flags; > - } else if (fimc_input_is_mipi_csi(endpoint.port)) { > + } else if (fimc_input_is_mipi_csi(endpoint.base.port)) { > /* > * MIPI CSI-2: only input mux selection and > * the sensor's clock frequency is needed. > @@ -508,7 +508,7 @@ static int fimc_md_parse_port_node(struct fimc_md *fmd, > pd->sensor_bus_type = FIMC_BUS_TYPE_MIPI_CSI2; > } else { > v4l2_err(&fmd->v4l2_dev, "Wrong port id (%u) at node %s\n", > - endpoint.port, rem->full_name); > + endpoint.base.port, rem->full_name); > } > /* > * For FIMC-IS handled sensors, that are placed under i2c-isp device > diff --git a/drivers/media/platform/exynos4-is/mipi-csis.c b/drivers/media/platform/exynos4-is/mipi-csis.c > index fd1ae65..3678ba5 100644 > --- a/drivers/media/platform/exynos4-is/mipi-csis.c > +++ b/drivers/media/platform/exynos4-is/mipi-csis.c > @@ -772,7 +772,7 @@ static int s5pcsis_parse_dt(struct platform_device *pdev, > /* Get port node and validate MIPI-CSI channel id. */ > v4l2_of_parse_endpoint(node,&endpoint); > > - state->index = endpoint.port - FIMC_INPUT_MIPI_CSI2_0; > + state->index = endpoint.base.port - FIMC_INPUT_MIPI_CSI2_0; > if (state->index< 0 || state->index>= CSIS_MAX_ENTITIES) > return -ENXIO; > > diff --git a/drivers/media/v4l2-core/v4l2-of.c b/drivers/media/v4l2-core/v4l2-of.c > index f919db3..b4ed9a9 100644 > --- a/drivers/media/v4l2-core/v4l2-of.c > +++ b/drivers/media/v4l2-core/v4l2-of.c > @@ -127,17 +127,9 @@ static void v4l2_of_parse_parallel_bus(const struct device_node *node, > int v4l2_of_parse_endpoint(const struct device_node *node, > struct v4l2_of_endpoint *endpoint) > { > - struct device_node *port_node = of_get_parent(node); > - > - memset(endpoint, 0, offsetof(struct v4l2_of_endpoint, head)); > - > - endpoint->local_node = node; > - /* > - * It doesn't matter whether the two calls below succeed. > - * If they don't then the default value 0 is used. > - */ > - of_property_read_u32(port_node, "reg",&endpoint->port); > - of_property_read_u32(node, "reg",&endpoint->id); > + of_graph_parse_endpoint(node,&endpoint->base); > + endpoint->bus_type = 0; > + memset(&endpoint->bus, 0, sizeof(endpoint->bus)); > > v4l2_of_parse_csi_bus(node, endpoint); > /* > @@ -147,8 +139,6 @@ int v4l2_of_parse_endpoint(const struct device_node *node, > if (endpoint->bus.mipi_csi2.flags == 0) > v4l2_of_parse_parallel_bus(node, endpoint); > > - of_node_put(port_node); > - > return 0; > } > EXPORT_SYMBOL(v4l2_of_parse_endpoint); > diff --git a/drivers/of/base.c b/drivers/of/base.c > index 8ecca7a..ba3cfca 100644 > --- a/drivers/of/base.c > +++ b/drivers/of/base.c > @@ -1985,6 +1985,37 @@ struct device_node *of_find_next_cache_node(const struct device_node *np) > } > > /** > + * of_graph_parse_endpoint() - parse common endpoint node properties > + * @node: pointer to endpoint device_node > + * @endpoint: pointer to the OF endpoint data structure > + * > + * All properties are optional. If none are found, we don't set any flags. > + * This means the port has a static configuration and no properties have > + * to be specified explicitly. I don't think these two sentences are needed, it's all described in the DT binding documentation. And struct of_endpoint doesn't contain any "flags" field. > + * The caller should hold a reference to @node. > + */ > +int of_graph_parse_endpoint(const struct device_node *node, > + struct of_endpoint *endpoint) > +{ > + struct device_node *port_node = of_get_parent(node); > + > + memset(endpoint, 0, sizeof(*endpoint)); > + > + endpoint->local_node = node; > + /* > + * It doesn't matter whether the two calls below succeed. > + * If they don't then the default value 0 is used. > + */ > + of_property_read_u32(port_node, "reg",&endpoint->port); > + of_property_read_u32(node, "reg",&endpoint->id); > + > + of_node_put(port_node); > + > + return 0; > +} > +EXPORT_SYMBOL(of_graph_parse_endpoint); > + > +/** > * of_graph_get_next_endpoint() - get next endpoint node > * @parent: pointer to the parent device node > * @prev: previous endpoint node, or NULL to get first > diff --git a/include/linux/of_graph.h b/include/linux/of_graph.h > index 3bbeb60..2b233db 100644 > --- a/include/linux/of_graph.h > +++ b/include/linux/of_graph.h > @@ -14,7 +14,21 @@ > #ifndef __LINUX_OF_GRAPH_H > #define __LINUX_OF_GRAPH_H > > +/** > + * struct of_endpoint - the OF graph endpoint data structure > + * @port: identifier (value of reg property) of a port this endpoint belongs to > + * @id: identifier (value of reg property) of this endpoint > + * @local_node: pointer to device_node of this endpoint > + */ > +struct of_endpoint { > + unsigned int port; > + unsigned int id; > + const struct device_node *local_node; > +}; > + > #ifdef CONFIG_OF > +int of_graph_parse_endpoint(const struct device_node *node, > + struct of_endpoint *endpoint); > struct device_node *of_graph_get_next_endpoint(const struct device_node *parent, > struct device_node *previous); > struct device_node *of_graph_get_remote_port_parent( > @@ -22,6 +36,12 @@ struct device_node *of_graph_get_remote_port_parent( > struct device_node *of_graph_get_remote_port(const struct device_node *node); > #else > > +static inline int of_graph_parse_endpoint(const struct device_node *node, > + struct of_endpoint *endpoint); > +{ > + return -ENOSYS; > +} > + > static inline struct device_node *of_graph_get_next_endpoint( > const struct device_node *parent, > struct device_node *previous) > diff --git a/include/media/v4l2-of.h b/include/media/v4l2-of.h > index 3a49735..70fa7b7 100644 > --- a/include/media/v4l2-of.h > +++ b/include/media/v4l2-of.h > @@ -51,17 +51,13 @@ struct v4l2_of_bus_parallel { > > /** > * struct v4l2_of_endpoint - the endpoint data structure > - * @port: identifier (value of reg property) of a port this endpoint belongs to > - * @id: identifier (value of reg property) of this endpoint > - * @local_node: pointer to device_node of this endpoint > + * @base: struct of_endpoint containing port, id, and local of_node > * @bus_type: bus type > * @bus: bus configuration data structure > * @head: list head for this structure > */ > struct v4l2_of_endpoint { > - unsigned int port; > - unsigned int id; > - const struct device_node *local_node; > + struct of_endpoint base; > enum v4l2_mbus_type bus_type; > union { > struct v4l2_of_bus_parallel parallel; Otherwise looks good to me. -- To unsubscribe from this list: send the line "unsubscribe linux-media" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
Hi Philipp, On 27/02/14 19:35, Philipp Zabel wrote: > This patch adds a new struct of_endpoint which is then embedded in struct > v4l2_of_endpoint and contains the endpoint properties that are not V4L2 > (or even media) specific: the port number, endpoint id, local device tree > node and remote endpoint phandle. of_graph_parse_endpoint parses those > properties and is used by v4l2_of_parse_endpoint, which just adds the > V4L2 MBUS information to the containing v4l2_of_endpoint structure. <snip> > diff --git a/drivers/of/base.c b/drivers/of/base.c > index 8ecca7a..ba3cfca 100644 > --- a/drivers/of/base.c > +++ b/drivers/of/base.c > @@ -1985,6 +1985,37 @@ struct device_node *of_find_next_cache_node(const struct device_node *np) > } > > /** > + * of_graph_parse_endpoint() - parse common endpoint node properties > + * @node: pointer to endpoint device_node > + * @endpoint: pointer to the OF endpoint data structure > + * > + * All properties are optional. If none are found, we don't set any flags. > + * This means the port has a static configuration and no properties have > + * to be specified explicitly. > + * The caller should hold a reference to @node. > + */ > +int of_graph_parse_endpoint(const struct device_node *node, > + struct of_endpoint *endpoint) > +{ > + struct device_node *port_node = of_get_parent(node); Can port_node be NULL? Probably only if something is quite wrong, but maybe it's safer to return error in that case. > + memset(endpoint, 0, sizeof(*endpoint)); > + > + endpoint->local_node = node; > + /* > + * It doesn't matter whether the two calls below succeed. > + * If they don't then the default value 0 is used. > + */ > + of_property_read_u32(port_node, "reg", &endpoint->port); > + of_property_read_u32(node, "reg", &endpoint->id); If the endpoint does not have 'port' as parent (i.e. the shortened format), the above will return the 'reg' of the device node (with 'device node' I mean the main node, with 'compatible' property). And generally speaking, if struct of_endpoint is needed, maybe it would be better to return the struct of_endpoint when iterating the ports and endpoints. That way there's no need to do parsing "afterwards", trying to figure out if there's a parent port node, but the information is already at hand. > + > + of_node_put(port_node); > + > + return 0; > +} > +EXPORT_SYMBOL(of_graph_parse_endpoint); > + > +/** > * of_graph_get_next_endpoint() - get next endpoint node > * @parent: pointer to the parent device node > * @prev: previous endpoint node, or NULL to get first > diff --git a/include/linux/of_graph.h b/include/linux/of_graph.h > index 3bbeb60..2b233db 100644 > --- a/include/linux/of_graph.h > +++ b/include/linux/of_graph.h > @@ -14,7 +14,21 @@ > #ifndef __LINUX_OF_GRAPH_H > #define __LINUX_OF_GRAPH_H > > +/** > + * struct of_endpoint - the OF graph endpoint data structure > + * @port: identifier (value of reg property) of a port this endpoint belongs to > + * @id: identifier (value of reg property) of this endpoint > + * @local_node: pointer to device_node of this endpoint > + */ > +struct of_endpoint { > + unsigned int port; > + unsigned int id; > + const struct device_node *local_node; > +}; A few thoughts about the iteration, and the API in general. In the omapdss version I separated iterating ports and endpoints, for the two reasons: 1) I think there are cases where you may want to have properties in the port node, for things that are common for all the port's endpoints. 2) if there are multiple ports, I think the driver code is cleaner if you first take the port, decide what port that is and maybe call a sub-function, and then iterate the endpoints for that port only. Both of those are possible with the API in the series, but not very cleanly. Also, if you just want to iterate the endpoints, it's easy to implement a helper using the separate port and endpoint iterations. Then, about the get_remote functions: I think there should be only one function for that purpose, one that returns the device node that contains the remote endpoint. My reasoning is that the ports and endpoints, and their contents, should be private to the device. So the only use to get the remote is to get the actual device, to see if it's been probed, or maybe get some video API for that device. If the driver model used has some kind of master-driver, which goes through all the display entities, I think the above is still valid. When the master-driver follows the remote-link, it still needs to first get the main device node, as the ports and endpoints make no sense without the context of the main device node. Tomi
Am Freitag, den 28.02.2014, 22:09 +0100 schrieb Sylwester Nawrocki: [...] > > --- a/drivers/of/base.c > > +++ b/drivers/of/base.c > > @@ -1985,6 +1985,37 @@ struct device_node *of_find_next_cache_node(const struct device_node *np) > > } > > > > /** > > + * of_graph_parse_endpoint() - parse common endpoint node properties > > + * @node: pointer to endpoint device_node > > + * @endpoint: pointer to the OF endpoint data structure > > + * > > + * All properties are optional. If none are found, we don't set any flags. > > + * This means the port has a static configuration and no properties have > > + * to be specified explicitly. > > I don't think these two sentences are needed, it's all described in the > DT binding documentation. And struct of_endpoint doesn't contain any > "flags" field. Thanks, I'll remove them. regards Philipp -- To unsubscribe from this list: send the line "unsubscribe linux-media" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
Hi Tomi, Am Dienstag, den 04.03.2014, 10:58 +0200 schrieb Tomi Valkeinen: [...] > > +int of_graph_parse_endpoint(const struct device_node *node, > > + struct of_endpoint *endpoint) > > +{ > > + struct device_node *port_node = of_get_parent(node); > > Can port_node be NULL? Probably only if something is quite wrong, but > maybe it's safer to return error in that case. both of_property_read_u32 and of_node_put can handle port_node == NULL. I'll add a WARN_ONCE here as for of_graph_get_next_endpoint and continue on. > > + memset(endpoint, 0, sizeof(*endpoint)); > > + > > + endpoint->local_node = node; > > + /* > > + * It doesn't matter whether the two calls below succeed. > > + * If they don't then the default value 0 is used. > > + */ > > + of_property_read_u32(port_node, "reg", &endpoint->port); > > + of_property_read_u32(node, "reg", &endpoint->id); > > If the endpoint does not have 'port' as parent (i.e. the shortened > format), the above will return the 'reg' of the device node (with > 'device node' I mean the main node, with 'compatible' property). Yes, a check for the port_node name is in order. > And generally speaking, if struct of_endpoint is needed, maybe it would > be better to return the struct of_endpoint when iterating the ports and > endpoints. That way there's no need to do parsing "afterwards", trying > to figure out if there's a parent port node, but the information is > already at hand. I'd like to keep the iteration separate from parsing so we can eventually introduce a for_each_endpoint_of_node helper macro around of_graph_get_next_endpoint. [...] > A few thoughts about the iteration, and the API in general. > > In the omapdss version I separated iterating ports and endpoints, for > the two reasons: > > 1) I think there are cases where you may want to have properties in the > port node, for things that are common for all the port's endpoints. > > 2) if there are multiple ports, I think the driver code is cleaner if > you first take the port, decide what port that is and maybe call a > sub-function, and then iterate the endpoints for that port only. It depends a bit on whether you are actually iterating over individual ports, or if you are just walking the whole endpoint graph to find remote devices that have to be added to the component master's waiting list, for example. > Both of those are possible with the API in the series, but not very cleanly. > > Also, if you just want to iterate the endpoints, it's easy to implement > a helper using the separate port and endpoint iterations. I started out to move an existing (albeit lightly used) API to a common place so others can use it and improve upon it, too. I'm happy to pile on fixes directly in this series, but could we separate the improvement step from the move, for the bigger modifications? I had no immediate use for the port iteration, so I have taken no steps to add a function for this. I see no problem to add this later when somebody needs it, or even rewrite of_graph_get_next_endpoint to use it if it is feasible. Iterating over endpoints on a given port needs no helper, as you can just use for_each_child_of_node. > Then, about the get_remote functions: I think there should be only one > function for that purpose, one that returns the device node that > contains the remote endpoint. > > My reasoning is that the ports and endpoints, and their contents, should > be private to the device. So the only use to get the remote is to get > the actual device, to see if it's been probed, or maybe get some video > API for that device. of_graph_get_remote_port currently is used in the exynos4-is/fimc-is.c v4l2 driver to get the mipi-csi channel id from the remote port, and I've started using it in imx-drm-core.c for two cases: - given an endpoint on the encoder, find the remote port connected to it, get the associated drm_crtc, to obtain its the drm_crtc_mask for encoder->possible_crtcs. - given an encoder and a connected drm_crtc, walk all endpoints to find the remote port associated with the drm_crtc, and then use the local endpoint parent port to determine multiplexer settings. > If the driver model used has some kind of master-driver, which goes > through all the display entities, I think the above is still valid. When > the master-driver follows the remote-link, it still needs to first get > the main device node, as the ports and endpoints make no sense without > the context of the main device node. I'm not sure about this. I might just need the remote port node associated with a remote drm_crtc or drm_encoder structure to find out which local endpoint I should look at to retrieve configuration. regards Philipp -- To unsubscribe from this list: send the line "unsubscribe linux-media" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
On 04/03/14 13:36, Philipp Zabel wrote: > Hi Tomi, > > Am Dienstag, den 04.03.2014, 10:58 +0200 schrieb Tomi Valkeinen: > [...] >>> +int of_graph_parse_endpoint(const struct device_node *node, >>> + struct of_endpoint *endpoint) >>> +{ >>> + struct device_node *port_node = of_get_parent(node); >> >> Can port_node be NULL? Probably only if something is quite wrong, but >> maybe it's safer to return error in that case. > > both of_property_read_u32 and of_node_put can handle port_node == NULL. > I'll add a WARN_ONCE here as for of_graph_get_next_endpoint and continue > on. Isn't it better to return an error? >> And generally speaking, if struct of_endpoint is needed, maybe it would >> be better to return the struct of_endpoint when iterating the ports and >> endpoints. That way there's no need to do parsing "afterwards", trying >> to figure out if there's a parent port node, but the information is >> already at hand. > > I'd like to keep the iteration separate from parsing so we can > eventually introduce a for_each_endpoint_of_node helper macro around > of_graph_get_next_endpoint. > > [...] >> A few thoughts about the iteration, and the API in general. >> >> In the omapdss version I separated iterating ports and endpoints, for >> the two reasons: >> >> 1) I think there are cases where you may want to have properties in the >> port node, for things that are common for all the port's endpoints. >> >> 2) if there are multiple ports, I think the driver code is cleaner if >> you first take the port, decide what port that is and maybe call a >> sub-function, and then iterate the endpoints for that port only. > > It depends a bit on whether you are actually iterating over individual > ports, or if you are just walking the whole endpoint graph to find > remote devices that have to be added to the component master's waiting > list, for example. True, but the latter is easily implemented using the separate port/endpoint iteration. So I see it as a more powerful API. >> Both of those are possible with the API in the series, but not very cleanly. >> >> Also, if you just want to iterate the endpoints, it's easy to implement >> a helper using the separate port and endpoint iterations. > > I started out to move an existing (albeit lightly used) API to a common > place so others can use it and improve upon it, too. I'm happy to pile > on fixes directly in this series, but could we separate the improvement > step from the move, for the bigger modifications? Yes, I understand that. What I wonder is that which is easier: make it a public API now, more or less as it was in v4l2, or make it a public API only when all the improvements we can think of have been made. So my fear is that the API is now made public, and you and others start to use it. But I can't use it, as I need things like separate port/endpoint iteration. I need to add those, which also means that I need to change all the users of the API, making the task more difficult than I'd like. However, this is more of "thinking out loud" than "I don't like the series". It's a good series =). > I had no immediate use for the port iteration, so I have taken no steps > to add a function for this. I see no problem to add this later when > somebody needs it, or even rewrite of_graph_get_next_endpoint to use it > if it is feasible. Iterating over endpoints on a given port needs no > helper, as you can just use for_each_child_of_node. I would have a helper, which should do some sanity checks, like that the node names are "endpoint". >> Then, about the get_remote functions: I think there should be only one >> function for that purpose, one that returns the device node that >> contains the remote endpoint. >> >> My reasoning is that the ports and endpoints, and their contents, should >> be private to the device. So the only use to get the remote is to get >> the actual device, to see if it's been probed, or maybe get some video >> API for that device. > > of_graph_get_remote_port currently is used in the exynos4-is/fimc-is.c > v4l2 driver to get the mipi-csi channel id from the remote port, and > I've started using it in imx-drm-core.c for two cases: > - given an endpoint on the encoder, find the remote port connected to > it, get the associated drm_crtc, to obtain its the drm_crtc_mask > for encoder->possible_crtcs. > - given an encoder and a connected drm_crtc, walk all endpoints to find > the remote port associated with the drm_crtc, and then use the local > endpoint parent port to determine multiplexer settings. Ok. In omapdss each driver handles only the ports and endpoints defined for its device, and they can be considered private to that device. The only reason to look for the remote endpoint is to find the remote device. To me the omapdss model makes sense, and feels logical and sane =). So I have to say I'm not really familiar with the model you're using. Of course, the different get_remove_* funcs do no harm, even if we have a bunch of them. My point was only about enforcing the correct use of the model, where "correct" is of course subjective =). >> If the driver model used has some kind of master-driver, which goes >> through all the display entities, I think the above is still valid. When >> the master-driver follows the remote-link, it still needs to first get >> the main device node, as the ports and endpoints make no sense without >> the context of the main device node. > > I'm not sure about this. I might just need the remote port node > associated with a remote drm_crtc or drm_encoder structure to find out > which local endpoint I should look at to retrieve configuration. Ok. I guess if you have a fixed model for the video pipeline elements it works out. For omapdss we don't know what's there on the remote side, as we can have arbitrary amount of video pipeline elements. Tomi
Am Dienstag, den 04.03.2014, 14:21 +0200 schrieb Tomi Valkeinen: > On 04/03/14 13:36, Philipp Zabel wrote: [...] > >> Can port_node be NULL? Probably only if something is quite wrong, but > >> maybe it's safer to return error in that case. > > > > both of_property_read_u32 and of_node_put can handle port_node == NULL. > > I'll add a WARN_ONCE here as for of_graph_get_next_endpoint and continue > > on. > > Isn't it better to return an error? I am not sure. We can still correctly parse the endpoint properties of a parentless node. All current users ignore the return value anyway. So as long as we still do the memset and and set local_node and id, returning an error effectively won't change the current behaviour. [...] > > It depends a bit on whether you are actually iterating over individual > > ports, or if you are just walking the whole endpoint graph to find > > remote devices that have to be added to the component master's waiting > > list, for example. > > True, but the latter is easily implemented using the separate > port/endpoint iteration. So I see it as a more powerful API. Indeed. I see no problem in adding an of_graph_get_next_port function. But I'd like to keep the current of_graph_get_next_endpoint function iterating over all endpoints of the device. > >> Both of those are possible with the API in the series, but not very cleanly. > >> > >> Also, if you just want to iterate the endpoints, it's easy to implement > >> a helper using the separate port and endpoint iterations. > > > > I started out to move an existing (albeit lightly used) API to a common > > place so others can use it and improve upon it, too. I'm happy to pile > > on fixes directly in this series, but could we separate the improvement > > step from the move, for the bigger modifications? > > Yes, I understand that. What I wonder is that which is easier: make it a > public API now, more or less as it was in v4l2, or make it a public API > only when all the improvements we can think of have been made. > > So my fear is that the API is now made public, and you and others start > to use it. And I fear that this series might outgrow maintainer attention spans if I keep adding to it. > But I can't use it, as I need things like separate > port/endpoint iteration. I need to add those, which also means that I > need to change all the users of the API, making the task more difficult > than I'd like. > > However, this is more of "thinking out loud" than "I don't like the > series". It's a good series =). Thanks. How about I follow this up with a split port/endpoint parsing helpers after I get some acks? > > I had no immediate use for the port iteration, so I have taken no steps > > to add a function for this. I see no problem to add this later when > > somebody needs it, or even rewrite of_graph_get_next_endpoint to use it > > if it is feasible. Iterating over endpoints on a given port needs no > > helper, as you can just use for_each_child_of_node. > > I would have a helper, which should do some sanity checks, like that the > node names are "endpoint". I'd prefer this to be a generic function of_get_next_child_by_name and possibly a macro for_each_named_child_of_node wrapping that. [...] > In omapdss each driver handles only the ports and endpoints defined for > its device, and they can be considered private to that device. The only > reason to look for the remote endpoint is to find the remote device. To > me the omapdss model makes sense, and feels logical and sane =). So I > have to say I'm not really familiar with the model you're using. The main difference I see is that a single IPU device will have two port nodes handled by the DRM driver and two port nodes handled by the V4L2 driver, so we can't go back up to the IPU device tree node and iterate over all its ports in either the DRM or V4L2 drivers. You could argue that all the device tree parsing should be done from the IPU drivers, and the DRM and V4L2 drivers should use preparsed internal graph structures. But then we are getting into using struct media_entity in DRM drivers territory, and rather not go there right now. regards Philipp -- To unsubscribe from this list: send the line "unsubscribe linux-media" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
On 04/03/14 17:47, Philipp Zabel wrote: > Am Dienstag, den 04.03.2014, 14:21 +0200 schrieb Tomi Valkeinen: >> On 04/03/14 13:36, Philipp Zabel wrote: > [...] >>>> Can port_node be NULL? Probably only if something is quite wrong, but >>>> maybe it's safer to return error in that case. >>> >>> both of_property_read_u32 and of_node_put can handle port_node == NULL. >>> I'll add a WARN_ONCE here as for of_graph_get_next_endpoint and continue >>> on. >> >> Isn't it better to return an error? > > I am not sure. We can still correctly parse the endpoint properties of a > parentless node. All current users ignore the return value anyway. So as > long as we still do the memset and and set local_node and id, returning > an error effectively won't change the current behaviour. Is the parentless node case an error or not? If it's not, we can handle it silently and return 0, no WARN needed. If it is an error, we should return an error, even if nobody is currently handling that (which is a bug in itself, as the function does return an error value, and callers should handle it). Tomi
Hi Tomi, On Tuesday 04 March 2014 14:21:09 Tomi Valkeinen wrote: > On 04/03/14 13:36, Philipp Zabel wrote: > > Am Dienstag, den 04.03.2014, 10:58 +0200 schrieb Tomi Valkeinen: > > [...] [snip] > >> Then, about the get_remote functions: I think there should be only one > >> function for that purpose, one that returns the device node that > >> contains the remote endpoint. > >> > >> My reasoning is that the ports and endpoints, and their contents, should > >> be private to the device. So the only use to get the remote is to get > >> the actual device, to see if it's been probed, or maybe get some video > >> API for that device. > > > > of_graph_get_remote_port currently is used in the exynos4-is/fimc-is.c > > v4l2 driver to get the mipi-csi channel id from the remote port, and > > I've started using it in imx-drm-core.c for two cases: > > - given an endpoint on the encoder, find the remote port connected to > > it, get the associated drm_crtc, to obtain its the drm_crtc_mask > > for encoder->possible_crtcs. > > > > - given an encoder and a connected drm_crtc, walk all endpoints to find > > the remote port associated with the drm_crtc, and then use the local > > endpoint parent port to determine multiplexer settings. > > Ok. > > In omapdss each driver handles only the ports and endpoints defined for > its device, and they can be considered private to that device. The only > reason to look for the remote endpoint is to find the remote device. To > me the omapdss model makes sense, and feels logical and sane =). So I > have to say I'm not really familiar with the model you're using. I agree with you that most of the content of the remote endpoint should be considered private to the remote device and not accessed by the local device driver. There is, however, one piece of information from the remote endpoint useful to the local device driver, it's the remote port identifier. This can be expressed by a phandle, a remote port number, a media entity pad pointer, or any other mean, but the information is useful for the local device driver to communicate with the remote device driver. For instance a driver could use it to ask its video stream source to start the video stream on a given port. > Of course, the different get_remove_* funcs do no harm, even if we have > a bunch of them. My point was only about enforcing the correct use of > the model, where "correct" is of course subjective =).
diff --git a/drivers/media/platform/exynos4-is/media-dev.c b/drivers/media/platform/exynos4-is/media-dev.c index d0f82da..04d6ecd 100644 --- a/drivers/media/platform/exynos4-is/media-dev.c +++ b/drivers/media/platform/exynos4-is/media-dev.c @@ -469,10 +469,10 @@ static int fimc_md_parse_port_node(struct fimc_md *fmd, return 0; v4l2_of_parse_endpoint(ep, &endpoint); - if (WARN_ON(endpoint.port == 0) || index >= FIMC_MAX_SENSORS) + if (WARN_ON(endpoint.base.port == 0) || index >= FIMC_MAX_SENSORS) return -EINVAL; - pd->mux_id = (endpoint.port - 1) & 0x1; + pd->mux_id = (endpoint.base.port - 1) & 0x1; rem = of_graph_get_remote_port_parent(ep); of_node_put(ep); @@ -494,13 +494,13 @@ static int fimc_md_parse_port_node(struct fimc_md *fmd, return -EINVAL; } - if (fimc_input_is_parallel(endpoint.port)) { + if (fimc_input_is_parallel(endpoint.base.port)) { if (endpoint.bus_type == V4L2_MBUS_PARALLEL) pd->sensor_bus_type = FIMC_BUS_TYPE_ITU_601; else pd->sensor_bus_type = FIMC_BUS_TYPE_ITU_656; pd->flags = endpoint.bus.parallel.flags; - } else if (fimc_input_is_mipi_csi(endpoint.port)) { + } else if (fimc_input_is_mipi_csi(endpoint.base.port)) { /* * MIPI CSI-2: only input mux selection and * the sensor's clock frequency is needed. @@ -508,7 +508,7 @@ static int fimc_md_parse_port_node(struct fimc_md *fmd, pd->sensor_bus_type = FIMC_BUS_TYPE_MIPI_CSI2; } else { v4l2_err(&fmd->v4l2_dev, "Wrong port id (%u) at node %s\n", - endpoint.port, rem->full_name); + endpoint.base.port, rem->full_name); } /* * For FIMC-IS handled sensors, that are placed under i2c-isp device diff --git a/drivers/media/platform/exynos4-is/mipi-csis.c b/drivers/media/platform/exynos4-is/mipi-csis.c index fd1ae65..3678ba5 100644 --- a/drivers/media/platform/exynos4-is/mipi-csis.c +++ b/drivers/media/platform/exynos4-is/mipi-csis.c @@ -772,7 +772,7 @@ static int s5pcsis_parse_dt(struct platform_device *pdev, /* Get port node and validate MIPI-CSI channel id. */ v4l2_of_parse_endpoint(node, &endpoint); - state->index = endpoint.port - FIMC_INPUT_MIPI_CSI2_0; + state->index = endpoint.base.port - FIMC_INPUT_MIPI_CSI2_0; if (state->index < 0 || state->index >= CSIS_MAX_ENTITIES) return -ENXIO; diff --git a/drivers/media/v4l2-core/v4l2-of.c b/drivers/media/v4l2-core/v4l2-of.c index f919db3..b4ed9a9 100644 --- a/drivers/media/v4l2-core/v4l2-of.c +++ b/drivers/media/v4l2-core/v4l2-of.c @@ -127,17 +127,9 @@ static void v4l2_of_parse_parallel_bus(const struct device_node *node, int v4l2_of_parse_endpoint(const struct device_node *node, struct v4l2_of_endpoint *endpoint) { - struct device_node *port_node = of_get_parent(node); - - memset(endpoint, 0, offsetof(struct v4l2_of_endpoint, head)); - - endpoint->local_node = node; - /* - * It doesn't matter whether the two calls below succeed. - * If they don't then the default value 0 is used. - */ - of_property_read_u32(port_node, "reg", &endpoint->port); - of_property_read_u32(node, "reg", &endpoint->id); + of_graph_parse_endpoint(node, &endpoint->base); + endpoint->bus_type = 0; + memset(&endpoint->bus, 0, sizeof(endpoint->bus)); v4l2_of_parse_csi_bus(node, endpoint); /* @@ -147,8 +139,6 @@ int v4l2_of_parse_endpoint(const struct device_node *node, if (endpoint->bus.mipi_csi2.flags == 0) v4l2_of_parse_parallel_bus(node, endpoint); - of_node_put(port_node); - return 0; } EXPORT_SYMBOL(v4l2_of_parse_endpoint); diff --git a/drivers/of/base.c b/drivers/of/base.c index 8ecca7a..ba3cfca 100644 --- a/drivers/of/base.c +++ b/drivers/of/base.c @@ -1985,6 +1985,37 @@ struct device_node *of_find_next_cache_node(const struct device_node *np) } /** + * of_graph_parse_endpoint() - parse common endpoint node properties + * @node: pointer to endpoint device_node + * @endpoint: pointer to the OF endpoint data structure + * + * All properties are optional. If none are found, we don't set any flags. + * This means the port has a static configuration and no properties have + * to be specified explicitly. + * The caller should hold a reference to @node. + */ +int of_graph_parse_endpoint(const struct device_node *node, + struct of_endpoint *endpoint) +{ + struct device_node *port_node = of_get_parent(node); + + memset(endpoint, 0, sizeof(*endpoint)); + + endpoint->local_node = node; + /* + * It doesn't matter whether the two calls below succeed. + * If they don't then the default value 0 is used. + */ + of_property_read_u32(port_node, "reg", &endpoint->port); + of_property_read_u32(node, "reg", &endpoint->id); + + of_node_put(port_node); + + return 0; +} +EXPORT_SYMBOL(of_graph_parse_endpoint); + +/** * of_graph_get_next_endpoint() - get next endpoint node * @parent: pointer to the parent device node * @prev: previous endpoint node, or NULL to get first diff --git a/include/linux/of_graph.h b/include/linux/of_graph.h index 3bbeb60..2b233db 100644 --- a/include/linux/of_graph.h +++ b/include/linux/of_graph.h @@ -14,7 +14,21 @@ #ifndef __LINUX_OF_GRAPH_H #define __LINUX_OF_GRAPH_H +/** + * struct of_endpoint - the OF graph endpoint data structure + * @port: identifier (value of reg property) of a port this endpoint belongs to + * @id: identifier (value of reg property) of this endpoint + * @local_node: pointer to device_node of this endpoint + */ +struct of_endpoint { + unsigned int port; + unsigned int id; + const struct device_node *local_node; +}; + #ifdef CONFIG_OF +int of_graph_parse_endpoint(const struct device_node *node, + struct of_endpoint *endpoint); struct device_node *of_graph_get_next_endpoint(const struct device_node *parent, struct device_node *previous); struct device_node *of_graph_get_remote_port_parent( @@ -22,6 +36,12 @@ struct device_node *of_graph_get_remote_port_parent( struct device_node *of_graph_get_remote_port(const struct device_node *node); #else +static inline int of_graph_parse_endpoint(const struct device_node *node, + struct of_endpoint *endpoint); +{ + return -ENOSYS; +} + static inline struct device_node *of_graph_get_next_endpoint( const struct device_node *parent, struct device_node *previous) diff --git a/include/media/v4l2-of.h b/include/media/v4l2-of.h index 3a49735..70fa7b7 100644 --- a/include/media/v4l2-of.h +++ b/include/media/v4l2-of.h @@ -51,17 +51,13 @@ struct v4l2_of_bus_parallel { /** * struct v4l2_of_endpoint - the endpoint data structure - * @port: identifier (value of reg property) of a port this endpoint belongs to - * @id: identifier (value of reg property) of this endpoint - * @local_node: pointer to device_node of this endpoint + * @base: struct of_endpoint containing port, id, and local of_node * @bus_type: bus type * @bus: bus configuration data structure * @head: list head for this structure */ struct v4l2_of_endpoint { - unsigned int port; - unsigned int id; - const struct device_node *local_node; + struct of_endpoint base; enum v4l2_mbus_type bus_type; union { struct v4l2_of_bus_parallel parallel;
This patch adds a new struct of_endpoint which is then embedded in struct v4l2_of_endpoint and contains the endpoint properties that are not V4L2 (or even media) specific: the port number, endpoint id, local device tree node and remote endpoint phandle. of_graph_parse_endpoint parses those properties and is used by v4l2_of_parse_endpoint, which just adds the V4L2 MBUS information to the containing v4l2_of_endpoint structure. Signed-off-by: Philipp Zabel <p.zabel@pengutronix.de> --- Changes since v4: - Fixed users of struct v4l2_of_endpoint - Removed left-over #include <media/of_graph.h> from v4l2-of.h --- drivers/media/platform/exynos4-is/media-dev.c | 10 ++++----- drivers/media/platform/exynos4-is/mipi-csis.c | 2 +- drivers/media/v4l2-core/v4l2-of.c | 16 +++----------- drivers/of/base.c | 31 +++++++++++++++++++++++++++ include/linux/of_graph.h | 20 +++++++++++++++++ include/media/v4l2-of.h | 8 ++----- 6 files changed, 62 insertions(+), 25 deletions(-)