On 01/03/2013 06:09 PM, Sylwester Nawrocki wrote: > From: Guennadi Liakhovetski <g.liakhovet...@gmx.de> > > Add a V4L2 OF parser, implementing bindings documented in > Documentation/devicetree/bindings/media/video-interfaces.txt. > > Signed-off-by: Guennadi Liakhovetski <g.liakhovet...@gmx.de> > Signed-off-by: Sylwester Nawrocki <s.nawro...@samsung.com>
Hans, Laurent, Mauro, would you have any comments on this ? Anything that needs to be changed/improved ? I'd like to send a pull request including this patch, together with an updated patch series [1] (v3) adding initial device tree support to the Exynos camera subsystem drivers. [1] http://www.spinics.net/lists/linux-media/msg57947.html Thanks, Sylwester > --- > Changes since v2: > - added missing EXPORT_SYMBOL for v4l2_of_parse_mipi_csi2() > and v4l2_of_parse_parallel_bus() functions, > - include string.h header instead of slab.h. > > drivers/media/v4l2-core/Makefile | 3 + > drivers/media/v4l2-core/v4l2-of.c | 251 > +++++++++++++++++++++++++++++++++++++ > include/media/v4l2-of.h | 79 ++++++++++++ > 3 files changed, 333 insertions(+) > create mode 100644 drivers/media/v4l2-core/v4l2-of.c > create mode 100644 include/media/v4l2-of.h > > diff --git a/drivers/media/v4l2-core/Makefile > b/drivers/media/v4l2-core/Makefile > index c2d61d4..00f64d6 100644 > --- a/drivers/media/v4l2-core/Makefile > +++ b/drivers/media/v4l2-core/Makefile > @@ -9,6 +9,9 @@ videodev-objs := v4l2-dev.o v4l2-ioctl.o v4l2-device.o > v4l2-fh.o \ > ifeq ($(CONFIG_COMPAT),y) > videodev-objs += v4l2-compat-ioctl32.o > endif > +ifeq ($(CONFIG_OF),y) > + videodev-objs += v4l2-of.o > +endif > > obj-$(CONFIG_VIDEO_DEV) += videodev.o v4l2-int-device.o > obj-$(CONFIG_VIDEO_V4L2) += v4l2-common.o > diff --git a/drivers/media/v4l2-core/v4l2-of.c > b/drivers/media/v4l2-core/v4l2-of.c > new file mode 100644 > index 0000000..483245c > --- /dev/null > +++ b/drivers/media/v4l2-core/v4l2-of.c > @@ -0,0 +1,251 @@ > +/* > + * V4L2 OF binding parsing library > + * > + * Copyright (C) 2012 Renesas Electronics Corp. > + * Author: Guennadi Liakhovetski <g.liakhovet...@gmx.de> > + * > + * This program is free software; you can redistribute it and/or modify > + * it under the terms of version 2 of the GNU General Public License as > + * published by the Free Software Foundation. > + */ > +#include <linux/kernel.h> > +#include <linux/module.h> > +#include <linux/of.h> > +#include <linux/string.h> > +#include <linux/types.h> > + > +#include <media/v4l2-of.h> > + > +/** > + * v4l2_of_parse_mipi_csi2() - parse MIPI CSI-2 bus properties > + * @node: pointer to endpoint device_node > + * @endpoint: pointer to v4l2_of_endpoint data structure > + * > + * Return: 0 on success or negative error value otherwise. > + */ > +int v4l2_of_parse_mipi_csi2(const struct device_node *node, > + struct v4l2_of_endpoint *endpoint) > +{ > + struct v4l2_of_mipi_csi2 *mipi_csi2 = &endpoint->mipi_csi_2; > + u32 data_lanes[ARRAY_SIZE(mipi_csi2->data_lanes)]; > + struct property *prop; > + const __be32 *lane = NULL; > + u32 v; > + int i = 0; > + > + prop = of_find_property(node, "data-lanes", NULL); > + if (!prop) > + return -EINVAL; > + do { > + lane = of_prop_next_u32(prop, lane, &data_lanes[i]); > + } while (lane && i++ < ARRAY_SIZE(data_lanes)); > + > + mipi_csi2->num_data_lanes = i; > + while (i--) > + mipi_csi2->data_lanes[i] = data_lanes[i]; > + > + if (!of_property_read_u32(node, "clock-lanes", &v)) > + mipi_csi2->clock_lane = v; > + > + if (of_get_property(node, "clock-noncontinuous", &v)) > + endpoint->mbus_flags |= V4L2_MBUS_CSI2_NONCONTINUOUS_CLOCK; > + > + return 0; > +} > +EXPORT_SYMBOL(v4l2_of_parse_mipi_csi2); > + > +/** > + * v4l2_of_parse_parallel_bus() - parse parallel bus properties > + * @node: pointer to endpoint device_node > + * @endpoint: pointer to v4l2_of_endpoint data structure > + */ > +void v4l2_of_parse_parallel_bus(const struct device_node *node, > + struct v4l2_of_endpoint *endpoint) > +{ > + unsigned int flags = 0; > + u32 v; > + > + if (WARN_ON(!endpoint)) > + return; > + > + if (!of_property_read_u32(node, "hsync-active", &v)) > + flags |= v ? V4L2_MBUS_HSYNC_ACTIVE_HIGH : > + V4L2_MBUS_HSYNC_ACTIVE_LOW; > + > + if (!of_property_read_u32(node, "vsync-active", &v)) > + flags |= v ? V4L2_MBUS_VSYNC_ACTIVE_HIGH : > + V4L2_MBUS_VSYNC_ACTIVE_LOW; > + > + if (!of_property_read_u32(node, "pclk-sample", &v)) > + flags |= v ? V4L2_MBUS_PCLK_SAMPLE_RISING : > + V4L2_MBUS_PCLK_SAMPLE_FALLING; > + > + if (!of_property_read_u32(node, "field-even-active", &v)) > + flags |= v ? V4L2_MBUS_FIELD_EVEN_HIGH : > + V4L2_MBUS_FIELD_EVEN_LOW; > + if (flags) > + endpoint->mbus_type = V4L2_MBUS_PARALLEL; > + else > + endpoint->mbus_type = V4L2_MBUS_BT656; > + > + if (!of_property_read_u32(node, "data-active", &v)) > + flags |= v ? V4L2_MBUS_DATA_ACTIVE_HIGH : > + V4L2_MBUS_DATA_ACTIVE_LOW; > + > + if (of_get_property(node, "slave-mode", &v)) > + flags |= V4L2_MBUS_SLAVE; > + > + if (!of_property_read_u32(node, "bus-width", &v)) > + endpoint->parallel.bus_width = v; > + > + if (!of_property_read_u32(node, "data-shift", &v)) > + endpoint->parallel.data_shift = v; > + > + endpoint->mbus_flags = flags; > +} > +EXPORT_SYMBOL(v4l2_of_parse_parallel_bus); > + > +/** > + * v4l2_of_parse_endpoint() - parse all endpoint node properties > + * @node: pointer to endpoint device_node > + * @endpoint: pointer to v4l2_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. > + * If any properties that identify the bus as parallel are found and > + * slave-mode isn't set, we set V4L2_MBUS_MASTER. Similarly, if we recognise > + * the bus as serial CSI-2 and clock-noncontinuous isn't set, we set the > + * V4L2_MBUS_CSI2_CONTINUOUS_CLOCK flag. > + * The caller should hold a reference to @node. > + */ > +void v4l2_of_parse_endpoint(const struct device_node *node, > + struct v4l2_of_endpoint *endpoint) > +{ > + const struct device_node *port_node = of_get_parent(node); > + bool data_lanes_present = false; > + > + memset(endpoint, 0, sizeof(*endpoint)); > + > + endpoint->local_node = node; > + > + /* Doesn't matter, whether the below two calls succeed */ > + of_property_read_u32(port_node, "reg", &endpoint->port); > + of_property_read_u32(node, "reg", &endpoint->addr); > + > + v4l2_of_parse_parallel_bus(node, endpoint); > + > + /* If any parallel bus properties have been found, skip serial ones */ > + if (endpoint->parallel.bus_width || endpoint->parallel.data_shift || > + endpoint->mbus_flags) { > + /* Default parallel bus-master */ > + if (!(endpoint->mbus_flags & V4L2_MBUS_SLAVE)) > + endpoint->mbus_flags |= V4L2_MBUS_MASTER; > + return; > + } > + > + endpoint->mbus_type = V4L2_MBUS_CSI2; > + > + if (!v4l2_of_parse_mipi_csi2(node, endpoint)) > + data_lanes_present = true; > + > + if ((endpoint->mipi_csi_2.clock_lane || data_lanes_present) && > + !(endpoint->mbus_flags & V4L2_MBUS_CSI2_NONCONTINUOUS_CLOCK)) { > + /* Default CSI-2: continuous clock */ > + endpoint->mbus_flags |= V4L2_MBUS_CSI2_CONTINUOUS_CLOCK; > + } > +} > +EXPORT_SYMBOL(v4l2_of_parse_endpoint); > + > +/* > + * Return a refcounted next "endpoint" DT node. Contrary to the common OF > + * practice, we do not drop the reference to previous, users have to do it > + * themselves, when they're done with the node. > + */ > +struct device_node *v4l2_of_get_next_endpoint(const struct device_node > *parent, > + struct device_node *previous) > +{ > + struct device_node *child, *port; > + > + if (!parent) > + return NULL; > + > + if (!previous) { > + /* > + * If this is the first call, we have to find a port within this > + * node > + */ > + for_each_child_of_node(parent, port) { > + if (!of_node_cmp(port->name, "port")) > + break; > + } > + if (port) { > + /* Found a port, get a link */ > + child = of_get_next_child(port, NULL); > + of_node_put(port); > + } else { > + child = NULL; > + } > + if (!child) > + pr_err("%s(): Invalid DT: %s has no link children!\n", > + __func__, parent->name); > + } else { > + port = of_get_parent(previous); > + if (!port) > + /* Hm, has someone given us the root node?... */ > + return NULL; > + > + /* Avoid dropping previous refcount to 0 */ > + of_node_get(previous); > + child = of_get_next_child(port, previous); > + if (child) { > + of_node_put(port); > + return child; > + } > + > + /* No more links under this port, try the next one */ > + do { > + port = of_get_next_child(parent, port); > + if (!port) > + return NULL; > + } while (of_node_cmp(port->name, "port")); > + > + /* Pick up the first link on this port */ > + child = of_get_next_child(port, NULL); > + of_node_put(port); > + } > + > + return child; > +} > +EXPORT_SYMBOL(v4l2_of_get_next_endpoint); > + > +/** > + * v4l2_of_get_remote_port_parent() - get remote port's parent node > + * @node: pointer to local endpoint device_node > + * > + * Return: Remote device node associated with remote endpoint node linked > + * to @node. Use of_node_put() on it when done. > + */ > +struct device_node *v4l2_of_get_remote_port_parent( > + const struct device_node *node) > +{ > + struct device_node *re, *tmp; > + > + /* Get remote endpoint DT node. */ > + re = of_parse_phandle(node, "remote-endpoint", 0); > + if (!re) > + return NULL; > + > + /* Remote port. */ > + tmp = of_get_parent(re); > + of_node_put(re); > + if (!tmp) > + return NULL; > + > + /* Remote device node. */ > + re = of_get_parent(tmp); > + of_node_put(tmp); > + > + return re; > +} > +EXPORT_SYMBOL(v4l2_of_get_remote_port_parent); > diff --git a/include/media/v4l2-of.h b/include/media/v4l2-of.h > new file mode 100644 > index 0000000..1aba3b3 > --- /dev/null > +++ b/include/media/v4l2-of.h > @@ -0,0 +1,79 @@ > +/* > + * V4L2 OF binding parsing library > + * > + * Copyright (C) 2012 Renesas Electronics Corp. > + * Author: Guennadi Liakhovetski <g.liakhovet...@gmx.de> > + * > + * This program is free software; you can redistribute it and/or modify > + * it under the terms of version 2 of the GNU General Public License as > + * published by the Free Software Foundation. > + */ > +#ifndef _V4L2_OF_H > +#define _V4L2_OF_H > + > +#include <linux/list.h> > +#include <linux/types.h> > +#include <linux/errno.h> > + > +#include <media/v4l2-mediabus.h> > + > +struct device_node; > + > +struct v4l2_of_mipi_csi2 { > + unsigned char data_lanes[4]; > + unsigned char clock_lane; > + unsigned short num_data_lanes; > +}; > + > +struct v4l2_of_endpoint { > + unsigned int port; > + unsigned int addr; > + struct list_head head; > + const struct device_node *local_node; > + const __be32 *remote; > + enum v4l2_mbus_type mbus_type; > + unsigned int mbus_flags; > + union { > + struct { > + unsigned char bus_width; > + unsigned char data_shift; > + } parallel; > + struct v4l2_of_mipi_csi2 mipi_csi_2; > + }; > +}; > + > +#ifdef CONFIG_OF > +int v4l2_of_parse_mipi_csi2(const struct device_node *node, > + struct v4l2_of_endpoint *endpoint); > +void v4l2_of_parse_parallel_bus(const struct device_node *node, > + struct v4l2_of_endpoint *endpoint); > +void v4l2_of_parse_endpoint(const struct device_node *node, > + struct v4l2_of_endpoint *link); > +struct device_node *v4l2_of_get_next_endpoint(const struct device_node > *parent, > + struct device_node *previous); > +struct device_node *v4l2_of_get_remote_port_parent( > + const struct device_node *node); > +#else /* CONFIG_OF */ > + > +static inline int v4l2_of_parse_endpoint(const struct device_node *node, > + struct v4l2_of_endpoint *link) > +{ > + return -ENOSYS; > +} > + > +static inline struct device_node *v4l2_of_get_next_endpoint( > + const struct device_node *parent, > + struct device_node *previous) > +{ > + return NULL; > +} > + > +static inline struct device_node *v4l2_of_get_remote_endpoint( > + const struct device_node *node) > +{ > + return NULL; > +} > + > +#endif /* CONFIG_OF */ > + > +#endif /* _V4L2_OF_H */ > -- > 1.7.9.5 -- To unsubscribe from this list: send the line "unsubscribe linux-media" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
