drivers/media/v4l2-core/v4l2-of.c - kernel/bruno - Git at Google

 /*
  * V4L2 OF binding parsing library
  *
  * Copyright (C) 2012 - 2013 Samsung Electronics Co., Ltd.
  * Author: Sylwester Nawrocki <s.nawrocki@samsung.com>
  *
  * Copyright (C) 2012 Renesas Electronics Corp.
  * Author: Guennadi Liakhovetski <g.liakhovetski@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/slab.h>
 #include <linux/string.h>
 #include <linux/types.h>

 #include <media/v4l2-of.h>

 static int v4l2_of_parse_csi_bus(const struct device_node *node,
 				 struct v4l2_of_endpoint *endpoint)
 {
 	struct v4l2_of_bus_mipi_csi2 *bus = &endpoint->bus.mipi_csi2;
 	struct property *prop;
 	bool have_clk_lane = false;
 	unsigned int flags = 0;
 	u32 v;

 	prop = of_find_property(node, "data-lanes", NULL);
 	if (prop) {
 		const __be32 *lane = NULL;
 		unsigned int i;

 		for (i = 0; i < ARRAY_SIZE(bus->data_lanes); i++) {
 			lane = of_prop_next_u32(prop, lane, &v);
 			if (!lane)
 				break;
 			bus->data_lanes[i] = v;
 		}
 		bus->num_data_lanes = i;
 	}

 	prop = of_find_property(node, "lane-polarities", NULL);
 	if (prop) {
 		const __be32 *polarity = NULL;
 		unsigned int i;

 		for (i = 0; i < ARRAY_SIZE(bus->lane_polarities); i++) {
 			polarity = of_prop_next_u32(prop, polarity, &v);
 			if (!polarity)
 				break;
 			bus->lane_polarities[i] = v;
 		}

 		if (i < 1 + bus->num_data_lanes /* clock + data */) {
 			pr_warn("%s: too few lane-polarities entries (need %u, got %u)\n",
 				node->full_name, 1 + bus->num_data_lanes, i);
 			return -EINVAL;
 		}
 	}

 	if (!of_property_read_u32(node, "clock-lanes", &v)) {
 		bus->clock_lane = v;
 		have_clk_lane = true;
 	}

 	if (of_get_property(node, "clock-noncontinuous", &v))
 		flags |= V4L2_MBUS_CSI2_NONCONTINUOUS_CLOCK;
 	else if (have_clk_lane || bus->num_data_lanes > 0)
 		flags |= V4L2_MBUS_CSI2_CONTINUOUS_CLOCK;

 	bus->flags = flags;
 	endpoint->bus_type = V4L2_MBUS_CSI2;

 	return 0;
 }

 static void v4l2_of_parse_parallel_bus(const struct device_node *node,
 				       struct v4l2_of_endpoint *endpoint)
 {
 	struct v4l2_of_bus_parallel *bus = &endpoint->bus.parallel;
 	unsigned int flags = 0;
 	u32 v;

 	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, "field-even-active", &v))
 		flags |= v ? V4L2_MBUS_FIELD_EVEN_HIGH :
 			V4L2_MBUS_FIELD_EVEN_LOW;
 	if (flags)
 		endpoint->bus_type = V4L2_MBUS_PARALLEL;
 	else
 		endpoint->bus_type = V4L2_MBUS_BT656;

 	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, "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;
 	else
 		flags |= V4L2_MBUS_MASTER;

 	if (!of_property_read_u32(node, "bus-width", &v))
 		bus->bus_width = v;

 	if (!of_property_read_u32(node, "data-shift", &v))
 		bus->data_shift = v;

 	if (!of_property_read_u32(node, "sync-on-green-active", &v))
 		flags |= v ? V4L2_MBUS_VIDEO_SOG_ACTIVE_HIGH :
 			V4L2_MBUS_VIDEO_SOG_ACTIVE_LOW;

 	bus->flags = flags;

 }

 /**
  * v4l2_of_parse_endpoint() - parse all endpoint node properties
  * @node: pointer to endpoint device_node
  * @endpoint: pointer to the 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.
  *
  * NOTE: This function does not parse properties the size of which is
  * variable without a low fixed limit. Please use
  * v4l2_of_alloc_parse_endpoint() in new drivers instead.
  *
  * Return: 0.
  */
 int v4l2_of_parse_endpoint(const struct device_node *node,
 			   struct v4l2_of_endpoint *endpoint)
 {
 	int rval;

 	of_graph_parse_endpoint(node, &endpoint->base);
 	/* Zero fields from bus_type to until the end */
 	memset(&endpoint->bus_type, 0, sizeof(*endpoint) -
 	       offsetof(typeof(*endpoint), bus_type));

 	rval = v4l2_of_parse_csi_bus(node, endpoint);
 	if (rval)
 		return rval;
 	/*
 	 * Parse the parallel video bus properties only if none
 	 * of the MIPI CSI-2 specific properties were found.
 	 */
 	if (endpoint->bus.mipi_csi2.flags == 0)
 		v4l2_of_parse_parallel_bus(node, endpoint);

 	return 0;
 }
 EXPORT_SYMBOL(v4l2_of_parse_endpoint);

 /*
  * v4l2_of_free_endpoint() - free the endpoint acquired by
  * v4l2_of_alloc_parse_endpoint()
  * @endpoint - the endpoint the resources of which are to be released
  *
  * It is safe to call this function with NULL argument or on an
  * endpoint the parsing of which failed.
  */
 void v4l2_of_free_endpoint(struct v4l2_of_endpoint *endpoint)
 {
 	if (IS_ERR_OR_NULL(endpoint))
 		return;

 	kfree(endpoint->link_frequencies);
 	kfree(endpoint);
 }
 EXPORT_SYMBOL(v4l2_of_free_endpoint);

 /**
  * v4l2_of_alloc_parse_endpoint() - parse all endpoint node properties
  * @node: pointer to endpoint device_node
  *
  * 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.
  *
  * v4l2_of_alloc_parse_endpoint() has two important differences to
  * v4l2_of_parse_endpoint():
  *
  * 1. It also parses variable size data and
  *
  * 2. The memory it has allocated to store the variable size data must
  *    be freed using v4l2_of_free_endpoint() when no longer needed.
  *
  * Return: Pointer to v4l2_of_endpoint if successful, on error a
  * negative error code.
  */
 struct v4l2_of_endpoint *v4l2_of_alloc_parse_endpoint(
 	const struct device_node *node)
 {
 	struct v4l2_of_endpoint *endpoint;
 	int len;
 	int rval;

 	endpoint = kzalloc(sizeof(*endpoint), GFP_KERNEL);
 	if (!endpoint)
 		return ERR_PTR(-ENOMEM);

 	rval = v4l2_of_parse_endpoint(node, endpoint);
 	if (rval < 0)
 		goto out_err;

 	if (of_get_property(node, "link-frequencies", &len)) {
 		endpoint->link_frequencies = kmalloc(len, GFP_KERNEL);
 		if (!endpoint->link_frequencies) {
 			rval = -ENOMEM;
 			goto out_err;
 		}

 		endpoint->nr_of_link_frequencies =
 			len / sizeof(*endpoint->link_frequencies);

 		rval = of_property_read_u64_array(
 			node, "link-frequencies", endpoint->link_frequencies,
 			endpoint->nr_of_link_frequencies);
 		if (rval < 0)
 			goto out_err;
 	}

 	return endpoint;

 out_err:
 	v4l2_of_free_endpoint(endpoint);
 	return ERR_PTR(rval);
 }
 EXPORT_SYMBOL(v4l2_of_alloc_parse_endpoint);

 /**
  * v4l2_of_parse_link() - parse a link between two endpoints
  * @node: pointer to the endpoint at the local end of the link
  * @link: pointer to the V4L2 OF link data structure
  *
  * Fill the link structure with the local and remote nodes and port numbers.
  * The local_node and remote_node fields are set to point to the local and
  * remote port's parent nodes respectively (the port parent node being the
  * parent node of the port node if that node isn't a 'ports' node, or the
  * grand-parent node of the port node otherwise).
  *
  * A reference is taken to both the local and remote nodes, the caller must use
  * v4l2_of_put_link() to drop the references when done with the link.
  *
  * Return: 0 on success, or -ENOLINK if the remote endpoint can't be found.
  */
 int v4l2_of_parse_link(const struct device_node *node,
 		       struct v4l2_of_link *link)
 {
 	struct device_node *np;

 	memset(link, 0, sizeof(*link));

 	np = of_get_parent(node);
 	of_property_read_u32(np, "reg", &link->local_port);
 	np = of_get_next_parent(np);
 	if (of_node_cmp(np->name, "ports") == 0)
 		np = of_get_next_parent(np);
 	link->local_node = np;

 	np = of_parse_phandle(node, "remote-endpoint", 0);
 	if (!np) {
 		of_node_put(link->local_node);
 		return -ENOLINK;
 	}

 	np = of_get_parent(np);
 	of_property_read_u32(np, "reg", &link->remote_port);
 	np = of_get_next_parent(np);
 	if (of_node_cmp(np->name, "ports") == 0)
 		np = of_get_next_parent(np);
 	link->remote_node = np;

 	return 0;
 }
 EXPORT_SYMBOL(v4l2_of_parse_link);

 /**
  * v4l2_of_put_link() - drop references to nodes in a link
  * @link: pointer to the V4L2 OF link data structure
  *
  * Drop references to the local and remote nodes in the link. This function must
  * be called on every link parsed with v4l2_of_parse_link().
  */
 void v4l2_of_put_link(struct v4l2_of_link *link)
 {
 	of_node_put(link->local_node);
 	of_node_put(link->remote_node);
 }
 EXPORT_SYMBOL(v4l2_of_put_link);
	/*
	* V4L2 OF binding parsing library
	*
	* Copyright (C) 2012 - 2013 Samsung Electronics Co., Ltd.
	* Author: Sylwester Nawrocki <s.nawrocki@samsung.com>
	*
	* Copyright (C) 2012 Renesas Electronics Corp.
	* Author: Guennadi Liakhovetski <g.liakhovetski@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/slab.h>
	#include <linux/string.h>
	#include <linux/types.h>

	#include <media/v4l2-of.h>

	static int v4l2_of_parse_csi_bus(const struct device_node *node,
	struct v4l2_of_endpoint *endpoint)
	{
	struct v4l2_of_bus_mipi_csi2 *bus = &endpoint->bus.mipi_csi2;
	struct property *prop;
	bool have_clk_lane = false;
	unsigned int flags = 0;
	u32 v;

	prop = of_find_property(node, "data-lanes", NULL);
	if (prop) {
	const __be32 *lane = NULL;
	unsigned int i;

	for (i = 0; i < ARRAY_SIZE(bus->data_lanes); i++) {
	lane = of_prop_next_u32(prop, lane, &v);
	if (!lane)
	break;
	bus->data_lanes[i] = v;
	}
	bus->num_data_lanes = i;
	}

	prop = of_find_property(node, "lane-polarities", NULL);
	if (prop) {
	const __be32 *polarity = NULL;
	unsigned int i;

	for (i = 0; i < ARRAY_SIZE(bus->lane_polarities); i++) {
	polarity = of_prop_next_u32(prop, polarity, &v);
	if (!polarity)
	break;
	bus->lane_polarities[i] = v;
	}

	if (i < 1 + bus->num_data_lanes /* clock + data */) {
	pr_warn("%s: too few lane-polarities entries (need %u, got %u)\n",
	node->full_name, 1 + bus->num_data_lanes, i);
	return -EINVAL;
	}
	}

	if (!of_property_read_u32(node, "clock-lanes", &v)) {
	bus->clock_lane = v;
	have_clk_lane = true;
	}

	if (of_get_property(node, "clock-noncontinuous", &v))
	flags \|= V4L2_MBUS_CSI2_NONCONTINUOUS_CLOCK;
	else if (have_clk_lane \|\| bus->num_data_lanes > 0)
	flags \|= V4L2_MBUS_CSI2_CONTINUOUS_CLOCK;

	bus->flags = flags;
	endpoint->bus_type = V4L2_MBUS_CSI2;

	return 0;
	}

	static void v4l2_of_parse_parallel_bus(const struct device_node *node,
	struct v4l2_of_endpoint *endpoint)
	{
	struct v4l2_of_bus_parallel *bus = &endpoint->bus.parallel;
	unsigned int flags = 0;
	u32 v;

	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, "field-even-active", &v))
	flags \|= v ? V4L2_MBUS_FIELD_EVEN_HIGH :
	V4L2_MBUS_FIELD_EVEN_LOW;
	if (flags)
	endpoint->bus_type = V4L2_MBUS_PARALLEL;
	else
	endpoint->bus_type = V4L2_MBUS_BT656;

	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, "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;
	else
	flags \|= V4L2_MBUS_MASTER;

	if (!of_property_read_u32(node, "bus-width", &v))
	bus->bus_width = v;

	if (!of_property_read_u32(node, "data-shift", &v))
	bus->data_shift = v;

	if (!of_property_read_u32(node, "sync-on-green-active", &v))
	flags \|= v ? V4L2_MBUS_VIDEO_SOG_ACTIVE_HIGH :
	V4L2_MBUS_VIDEO_SOG_ACTIVE_LOW;

	bus->flags = flags;

	}

	/**
	* v4l2_of_parse_endpoint() - parse all endpoint node properties
	* @node: pointer to endpoint device_node
	* @endpoint: pointer to the 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.
	*
	* NOTE: This function does not parse properties the size of which is
	* variable without a low fixed limit. Please use
	* v4l2_of_alloc_parse_endpoint() in new drivers instead.
	*
	* Return: 0.
	*/
	int v4l2_of_parse_endpoint(const struct device_node *node,
	struct v4l2_of_endpoint *endpoint)
	{
	int rval;

	of_graph_parse_endpoint(node, &endpoint->base);
	/* Zero fields from bus_type to until the end */
	memset(&endpoint->bus_type, 0, sizeof(*endpoint) -
	offsetof(typeof(*endpoint), bus_type));

	rval = v4l2_of_parse_csi_bus(node, endpoint);
	if (rval)
	return rval;
	/*
	* Parse the parallel video bus properties only if none
	* of the MIPI CSI-2 specific properties were found.
	*/
	if (endpoint->bus.mipi_csi2.flags == 0)
	v4l2_of_parse_parallel_bus(node, endpoint);

	return 0;
	}
	EXPORT_SYMBOL(v4l2_of_parse_endpoint);

	/*
	* v4l2_of_free_endpoint() - free the endpoint acquired by
	* v4l2_of_alloc_parse_endpoint()
	* @endpoint - the endpoint the resources of which are to be released
	*
	* It is safe to call this function with NULL argument or on an
	* endpoint the parsing of which failed.
	*/
	void v4l2_of_free_endpoint(struct v4l2_of_endpoint *endpoint)
	{
	if (IS_ERR_OR_NULL(endpoint))
	return;

	kfree(endpoint->link_frequencies);
	kfree(endpoint);
	}
	EXPORT_SYMBOL(v4l2_of_free_endpoint);

	/**
	* v4l2_of_alloc_parse_endpoint() - parse all endpoint node properties
	* @node: pointer to endpoint device_node
	*
	* 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.
	*
	* v4l2_of_alloc_parse_endpoint() has two important differences to
	* v4l2_of_parse_endpoint():
	*
	* 1. It also parses variable size data and
	*
	* 2. The memory it has allocated to store the variable size data must
	* be freed using v4l2_of_free_endpoint() when no longer needed.
	*
	* Return: Pointer to v4l2_of_endpoint if successful, on error a
	* negative error code.
	*/
	struct v4l2_of_endpoint *v4l2_of_alloc_parse_endpoint(
	const struct device_node *node)
	{
	struct v4l2_of_endpoint *endpoint;
	int len;
	int rval;

	endpoint = kzalloc(sizeof(*endpoint), GFP_KERNEL);
	if (!endpoint)
	return ERR_PTR(-ENOMEM);

	rval = v4l2_of_parse_endpoint(node, endpoint);
	if (rval < 0)
	goto out_err;

	if (of_get_property(node, "link-frequencies", &len)) {
	endpoint->link_frequencies = kmalloc(len, GFP_KERNEL);
	if (!endpoint->link_frequencies) {
	rval = -ENOMEM;
	goto out_err;
	}

	endpoint->nr_of_link_frequencies =
	len / sizeof(*endpoint->link_frequencies);

	rval = of_property_read_u64_array(
	node, "link-frequencies", endpoint->link_frequencies,
	endpoint->nr_of_link_frequencies);
	if (rval < 0)
	goto out_err;
	}

	return endpoint;

	out_err:
	v4l2_of_free_endpoint(endpoint);
	return ERR_PTR(rval);
	}
	EXPORT_SYMBOL(v4l2_of_alloc_parse_endpoint);

	/**
	* v4l2_of_parse_link() - parse a link between two endpoints
	* @node: pointer to the endpoint at the local end of the link
	* @link: pointer to the V4L2 OF link data structure
	*
	* Fill the link structure with the local and remote nodes and port numbers.
	* The local_node and remote_node fields are set to point to the local and
	* remote port's parent nodes respectively (the port parent node being the
	* parent node of the port node if that node isn't a 'ports' node, or the
	* grand-parent node of the port node otherwise).
	*
	* A reference is taken to both the local and remote nodes, the caller must use
	* v4l2_of_put_link() to drop the references when done with the link.
	*
	* Return: 0 on success, or -ENOLINK if the remote endpoint can't be found.
	*/
	int v4l2_of_parse_link(const struct device_node *node,
	struct v4l2_of_link *link)
	{
	struct device_node *np;

	memset(link, 0, sizeof(*link));

	np = of_get_parent(node);
	of_property_read_u32(np, "reg", &link->local_port);
	np = of_get_next_parent(np);
	if (of_node_cmp(np->name, "ports") == 0)
	np = of_get_next_parent(np);
	link->local_node = np;

	np = of_parse_phandle(node, "remote-endpoint", 0);
	if (!np) {
	of_node_put(link->local_node);
	return -ENOLINK;
	}

	np = of_get_parent(np);
	of_property_read_u32(np, "reg", &link->remote_port);
	np = of_get_next_parent(np);
	if (of_node_cmp(np->name, "ports") == 0)
	np = of_get_next_parent(np);
	link->remote_node = np;

	return 0;
	}
	EXPORT_SYMBOL(v4l2_of_parse_link);

	/**
	* v4l2_of_put_link() - drop references to nodes in a link
	* @link: pointer to the V4L2 OF link data structure
	*
	* Drop references to the local and remote nodes in the link. This function must
	* be called on every link parsed with v4l2_of_parse_link().
	*/
	void v4l2_of_put_link(struct v4l2_of_link *link)
	{
	of_node_put(link->local_node);
	of_node_put(link->remote_node);
	}
	EXPORT_SYMBOL(v4l2_of_put_link);