[mirror_ubuntu-bionic-kernel.git] / drivers / media / v4l2-core / v4l2-fwnode.c

/*
 * V4L2 fwnode binding parsing library
 *
 * The origins of the V4L2 fwnode library are in V4L2 OF library that
 * formerly was located in v4l2-of.c.
 *
 * Copyright (c) 2016 Intel Corporation.
 * Author: Sakari Ailus <sakari.ailus@linux.intel.com>
 *
 * 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/acpi.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/of.h>
#include <linux/property.h>
#include <linux/slab.h>
#include <linux/string.h>
#include <linux/types.h>

#include <media/v4l2-fwnode.h>

enum v4l2_fwnode_bus_type {
	V4L2_FWNODE_BUS_TYPE_GUESS = 0,
	V4L2_FWNODE_BUS_TYPE_CSI2_CPHY,
	V4L2_FWNODE_BUS_TYPE_CSI1,
	V4L2_FWNODE_BUS_TYPE_CCP2,
	NR_OF_V4L2_FWNODE_BUS_TYPE,
};

static int v4l2_fwnode_endpoint_parse_csi2_bus(struct fwnode_handle *fwnode,
					       struct v4l2_fwnode_endpoint *vep)
{
	struct v4l2_fwnode_bus_mipi_csi2 *bus = &vep->bus.mipi_csi2;
	bool have_clk_lane = false;
	unsigned int flags = 0, lanes_used = 0;
	unsigned int i;
	u32 v;
	int rval;

	rval = fwnode_property_read_u32_array(fwnode, "data-lanes", NULL, 0);
	if (rval > 0) {
		u32 array[1 + V4L2_FWNODE_CSI2_MAX_DATA_LANES];

		bus->num_data_lanes =
			min_t(int, V4L2_FWNODE_CSI2_MAX_DATA_LANES, rval);

		fwnode_property_read_u32_array(fwnode, "data-lanes", array,
					       bus->num_data_lanes);

		for (i = 0; i < bus->num_data_lanes; i++) {
			if (lanes_used & BIT(array[i]))
				pr_warn("duplicated lane %u in data-lanes\n",
					array[i]);
			lanes_used |= BIT(array[i]);

			bus->data_lanes[i] = array[i];
		}

		rval = fwnode_property_read_u32_array(fwnode,
						      "lane-polarities", NULL,
						      0);
		if (rval > 0) {
			if (rval != 1 + bus->num_data_lanes /* clock+data */) {
				pr_warn("invalid number of lane-polarities entries (need %u, got %u)\n",
					1 + bus->num_data_lanes, rval);
				return -EINVAL;
			}

			fwnode_property_read_u32_array(fwnode,
						       "lane-polarities", array,
						       1 + bus->num_data_lanes);

			for (i = 0; i < 1 + bus->num_data_lanes; i++)
				bus->lane_polarities[i] = array[i];
		}

	}

	if (!fwnode_property_read_u32(fwnode, "clock-lanes", &v)) {
		if (lanes_used & BIT(v))
			pr_warn("duplicated lane %u in clock-lanes\n", v);
		lanes_used |= BIT(v);

		bus->clock_lane = v;
		have_clk_lane = true;
	}

	if (fwnode_property_present(fwnode, "clock-noncontinuous"))
		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;
	vep->bus_type = V4L2_MBUS_CSI2;

	return 0;
}

static void v4l2_fwnode_endpoint_parse_parallel_bus(
	struct fwnode_handle *fwnode, struct v4l2_fwnode_endpoint *vep)
{
	struct v4l2_fwnode_bus_parallel *bus = &vep->bus.parallel;
	unsigned int flags = 0;
	u32 v;

	if (!fwnode_property_read_u32(fwnode, "hsync-active", &v))
		flags |= v ? V4L2_MBUS_HSYNC_ACTIVE_HIGH :
			V4L2_MBUS_HSYNC_ACTIVE_LOW;

	if (!fwnode_property_read_u32(fwnode, "vsync-active", &v))
		flags |= v ? V4L2_MBUS_VSYNC_ACTIVE_HIGH :
			V4L2_MBUS_VSYNC_ACTIVE_LOW;

	if (!fwnode_property_read_u32(fwnode, "field-even-active", &v))
		flags |= v ? V4L2_MBUS_FIELD_EVEN_HIGH :
			V4L2_MBUS_FIELD_EVEN_LOW;
	if (flags)
		vep->bus_type = V4L2_MBUS_PARALLEL;
	else
		vep->bus_type = V4L2_MBUS_BT656;

	if (!fwnode_property_read_u32(fwnode, "pclk-sample", &v))
		flags |= v ? V4L2_MBUS_PCLK_SAMPLE_RISING :
			V4L2_MBUS_PCLK_SAMPLE_FALLING;

	if (!fwnode_property_read_u32(fwnode, "data-active", &v))
		flags |= v ? V4L2_MBUS_DATA_ACTIVE_HIGH :
			V4L2_MBUS_DATA_ACTIVE_LOW;

	if (fwnode_property_present(fwnode, "slave-mode"))
		flags |= V4L2_MBUS_SLAVE;
	else
		flags |= V4L2_MBUS_MASTER;

	if (!fwnode_property_read_u32(fwnode, "bus-width", &v))
		bus->bus_width = v;

	if (!fwnode_property_read_u32(fwnode, "data-shift", &v))
		bus->data_shift = v;

	if (!fwnode_property_read_u32(fwnode, "sync-on-green-active", &v))
		flags |= v ? V4L2_MBUS_VIDEO_SOG_ACTIVE_HIGH :
			V4L2_MBUS_VIDEO_SOG_ACTIVE_LOW;

	bus->flags = flags;

}

static void
v4l2_fwnode_endpoint_parse_csi1_bus(struct fwnode_handle *fwnode,
				    struct v4l2_fwnode_endpoint *vep,
				    u32 bus_type)
{
	struct v4l2_fwnode_bus_mipi_csi1 *bus = &vep->bus.mipi_csi1;
	u32 v;

	if (!fwnode_property_read_u32(fwnode, "clock-inv", &v))
		bus->clock_inv = v;

	if (!fwnode_property_read_u32(fwnode, "strobe", &v))
		bus->strobe = v;

	if (!fwnode_property_read_u32(fwnode, "data-lanes", &v))
		bus->data_lane = v;

	if (!fwnode_property_read_u32(fwnode, "clock-lanes", &v))
		bus->clock_lane = v;

	if (bus_type == V4L2_FWNODE_BUS_TYPE_CCP2)
		vep->bus_type = V4L2_MBUS_CCP2;
	else
		vep->bus_type = V4L2_MBUS_CSI1;
}

/**
 * v4l2_fwnode_endpoint_parse() - parse all fwnode node properties
 * @fwnode: pointer to the endpoint's fwnode handle
 * @vep: pointer to the V4L2 fwnode 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 @fwnode.
 *
 * NOTE: This function does not parse properties the size of which is variable
 * without a low fixed limit. Please use v4l2_fwnode_endpoint_alloc_parse() in
 * new drivers instead.
 *
 * Return: 0 on success or a negative error code on failure.
 */
int v4l2_fwnode_endpoint_parse(struct fwnode_handle *fwnode,
			       struct v4l2_fwnode_endpoint *vep)
{
	u32 bus_type = 0;
	int rval;

	fwnode_graph_parse_endpoint(fwnode, &vep->base);

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

	fwnode_property_read_u32(fwnode, "bus-type", &bus_type);

	switch (bus_type) {
	case V4L2_FWNODE_BUS_TYPE_GUESS:
		rval = v4l2_fwnode_endpoint_parse_csi2_bus(fwnode, vep);
		if (rval)
			return rval;
		/*
		 * Parse the parallel video bus properties only if none
		 * of the MIPI CSI-2 specific properties were found.
		 */
		if (vep->bus.mipi_csi2.flags == 0)
			v4l2_fwnode_endpoint_parse_parallel_bus(fwnode, vep);

		return 0;
	case V4L2_FWNODE_BUS_TYPE_CCP2:
	case V4L2_FWNODE_BUS_TYPE_CSI1:
		v4l2_fwnode_endpoint_parse_csi1_bus(fwnode, vep, bus_type);

		return 0;
	default:
		pr_warn("unsupported bus type %u\n", bus_type);
		return -EINVAL;
	}
}
EXPORT_SYMBOL_GPL(v4l2_fwnode_endpoint_parse);

/*
 * v4l2_fwnode_endpoint_free() - free the V4L2 fwnode acquired by
 * v4l2_fwnode_endpoint_alloc_parse()
 * @vep - the V4L2 fwnode the resources of which are to be released
 *
 * It is safe to call this function with NULL argument or on a V4L2 fwnode the
 * parsing of which failed.
 */
void v4l2_fwnode_endpoint_free(struct v4l2_fwnode_endpoint *vep)
{
	if (IS_ERR_OR_NULL(vep))
		return;

	kfree(vep->link_frequencies);
	kfree(vep);
}
EXPORT_SYMBOL_GPL(v4l2_fwnode_endpoint_free);

/**
 * v4l2_fwnode_endpoint_alloc_parse() - parse all fwnode node properties
 * @fwnode: pointer to the endpoint's fwnode handle
 *
 * 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 @fwnode.
 *
 * v4l2_fwnode_endpoint_alloc_parse() has two important differences to
 * v4l2_fwnode_endpoint_parse():
 *
 * 1. It also parses variable size data.
 *
 * 2. The memory it has allocated to store the variable size data must be freed
 *    using v4l2_fwnode_endpoint_free() when no longer needed.
 *
 * Return: Pointer to v4l2_fwnode_endpoint if successful, on an error pointer
 * on error.
 */
struct v4l2_fwnode_endpoint *v4l2_fwnode_endpoint_alloc_parse(
	struct fwnode_handle *fwnode)
{
	struct v4l2_fwnode_endpoint *vep;
	int rval;

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

	rval = v4l2_fwnode_endpoint_parse(fwnode, vep);
	if (rval < 0)
		goto out_err;

	rval = fwnode_property_read_u64_array(fwnode, "link-frequencies",
					      NULL, 0);
	if (rval > 0) {
		vep->link_frequencies =
			kmalloc_array(rval, sizeof(*vep->link_frequencies),
				      GFP_KERNEL);
		if (!vep->link_frequencies) {
			rval = -ENOMEM;
			goto out_err;
		}

		vep->nr_of_link_frequencies = rval;

		rval = fwnode_property_read_u64_array(
			fwnode, "link-frequencies", vep->link_frequencies,
			vep->nr_of_link_frequencies);
		if (rval < 0)
			goto out_err;
	}

	return vep;

out_err:
	v4l2_fwnode_endpoint_free(vep);
	return ERR_PTR(rval);
}
EXPORT_SYMBOL_GPL(v4l2_fwnode_endpoint_alloc_parse);

/**
 * v4l2_fwnode_endpoint_parse_link() - parse a link between two endpoints
 * @__fwnode: pointer to the endpoint's fwnode at the local end of the link
 * @link: pointer to the V4L2 fwnode 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_fwnode_endpoint_put_link() to drop the references when done with the
 * link.
 *
 * Return: 0 on success, or -ENOLINK if the remote endpoint fwnode can't be
 * found.
 */
int v4l2_fwnode_parse_link(struct fwnode_handle *__fwnode,
			   struct v4l2_fwnode_link *link)
{
	const char *port_prop = is_of_node(__fwnode) ? "reg" : "port";
	struct fwnode_handle *fwnode;

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

	fwnode = fwnode_get_parent(__fwnode);
	fwnode_property_read_u32(fwnode, port_prop, &link->local_port);
	fwnode = fwnode_get_next_parent(fwnode);
	if (is_of_node(fwnode) &&
	    of_node_cmp(to_of_node(fwnode)->name, "ports") == 0)
		fwnode = fwnode_get_next_parent(fwnode);
	link->local_node = fwnode;

	fwnode = fwnode_graph_get_remote_endpoint(__fwnode);
	if (!fwnode) {
		fwnode_handle_put(fwnode);
		return -ENOLINK;
	}

	fwnode = fwnode_get_parent(fwnode);
	fwnode_property_read_u32(fwnode, port_prop, &link->remote_port);
	fwnode = fwnode_get_next_parent(fwnode);
	if (is_of_node(fwnode) &&
	    of_node_cmp(to_of_node(fwnode)->name, "ports") == 0)
		fwnode = fwnode_get_next_parent(fwnode);
	link->remote_node = fwnode;

	return 0;
}
EXPORT_SYMBOL_GPL(v4l2_fwnode_parse_link);

/**
 * v4l2_fwnode_put_link() - drop references to nodes in a link
 * @link: pointer to the V4L2 fwnode 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_fwnode_parse_link().
 */
void v4l2_fwnode_put_link(struct v4l2_fwnode_link *link)
{
	fwnode_handle_put(link->local_node);
	fwnode_handle_put(link->remote_node);
}
EXPORT_SYMBOL_GPL(v4l2_fwnode_put_link);

MODULE_LICENSE("GPL");
MODULE_AUTHOR("Sakari Ailus <sakari.ailus@linux.intel.com>");
MODULE_AUTHOR("Sylwester Nawrocki <s.nawrocki@samsung.com>");
MODULE_AUTHOR("Guennadi Liakhovetski <g.liakhovetski@gmx.de>");
Commit	Line	Data
ca50c197 SA	1	/*
	2	* V4L2 fwnode binding parsing library
	3	*
	4	* The origins of the V4L2 fwnode library are in V4L2 OF library that
	5	* formerly was located in v4l2-of.c.
	6	*
	7	* Copyright (c) 2016 Intel Corporation.
	8	* Author: Sakari Ailus <sakari.ailus@linux.intel.com>
	9	*
	10	* Copyright (C) 2012 - 2013 Samsung Electronics Co., Ltd.
	11	* Author: Sylwester Nawrocki <s.nawrocki@samsung.com>
	12	*
	13	* Copyright (C) 2012 Renesas Electronics Corp.
	14	* Author: Guennadi Liakhovetski <g.liakhovetski@gmx.de>
	15	*
	16	* This program is free software; you can redistribute it and/or modify
	17	* it under the terms of version 2 of the GNU General Public License as
	18	* published by the Free Software Foundation.
	19	*/
	20	#include <linux/acpi.h>
	21	#include <linux/kernel.h>
	22	#include <linux/module.h>
	23	#include <linux/of.h>
	24	#include <linux/property.h>
	25	#include <linux/slab.h>
	26	#include <linux/string.h>
	27	#include <linux/types.h>
	28
	29	#include <media/v4l2-fwnode.h>
	30
e07a41f9 SA	31	enum v4l2_fwnode_bus_type {
	32	V4L2_FWNODE_BUS_TYPE_GUESS = 0,
	33	V4L2_FWNODE_BUS_TYPE_CSI2_CPHY,
	34	V4L2_FWNODE_BUS_TYPE_CSI1,
	35	V4L2_FWNODE_BUS_TYPE_CCP2,
	36	NR_OF_V4L2_FWNODE_BUS_TYPE,
	37	};
	38
f3112735 SA	39	static int v4l2_fwnode_endpoint_parse_csi2_bus(struct fwnode_handle *fwnode,
f3112735 SA	40	struct v4l2_fwnode_endpoint *vep)
ca50c197 SA	41	{
	42	struct v4l2_fwnode_bus_mipi_csi2 *bus = &vep->bus.mipi_csi2;
	43	bool have_clk_lane = false;
	44	unsigned int flags = 0, lanes_used = 0;
	45	unsigned int i;
	46	u32 v;
	47	int rval;
	48
	49	rval = fwnode_property_read_u32_array(fwnode, "data-lanes", NULL, 0);
	50	if (rval > 0) {
ad3cdf3e	51	u32 array[1 + V4L2_FWNODE_CSI2_MAX_DATA_LANES];
ca50c197	52
ad3cdf3e SA	53	bus->num_data_lanes =
ad3cdf3e SA	54	min_t(int, V4L2_FWNODE_CSI2_MAX_DATA_LANES, rval);
ca50c197 SA	55
	56	fwnode_property_read_u32_array(fwnode, "data-lanes", array,
	57	bus->num_data_lanes);
	58
	59	for (i = 0; i < bus->num_data_lanes; i++) {
	60	if (lanes_used & BIT(array[i]))
	61	pr_warn("duplicated lane %u in data-lanes\n",
	62	array[i]);
	63	lanes_used \|= BIT(array[i]);
	64
	65	bus->data_lanes[i] = array[i];
	66	}
ca50c197	67
4ee23621	68	rval = fwnode_property_read_u32_array(fwnode,
b24f0215 SA	69	"lane-polarities", NULL,
b24f0215 SA	70	0);
4ee23621	71	if (rval > 0) {
b24f0215	72	if (rval != 1 + bus->num_data_lanes /* clock+data */) {
4ee23621 MCC	73	pr_warn("invalid number of lane-polarities entries (need %u, got %u)\n",
	74	1 + bus->num_data_lanes, rval);
	75	return -EINVAL;
	76	}
ca50c197	77
b24f0215 SA	78	fwnode_property_read_u32_array(fwnode,
	79	"lane-polarities", array,
	80	1 + bus->num_data_lanes);
ca50c197	81
4ee23621 MCC	82	for (i = 0; i < 1 + bus->num_data_lanes; i++)
	83	bus->lane_polarities[i] = array[i];
	84	}
b24f0215	85
ca50c197 SA	86	}
	87
	88	if (!fwnode_property_read_u32(fwnode, "clock-lanes", &v)) {
	89	if (lanes_used & BIT(v))
	90	pr_warn("duplicated lane %u in clock-lanes\n", v);
	91	lanes_used \|= BIT(v);
	92
	93	bus->clock_lane = v;
	94	have_clk_lane = true;
	95	}
	96
	97	if (fwnode_property_present(fwnode, "clock-noncontinuous"))
	98	flags \|= V4L2_MBUS_CSI2_NONCONTINUOUS_CLOCK;
	99	else if (have_clk_lane \|\| bus->num_data_lanes > 0)
	100	flags \|= V4L2_MBUS_CSI2_CONTINUOUS_CLOCK;
	101
	102	bus->flags = flags;
	103	vep->bus_type = V4L2_MBUS_CSI2;
	104
	105	return 0;
	106	}
	107
	108	static void v4l2_fwnode_endpoint_parse_parallel_bus(
	109	struct fwnode_handle fwnode, struct v4l2_fwnode_endpoint vep)
	110	{
	111	struct v4l2_fwnode_bus_parallel *bus = &vep->bus.parallel;
	112	unsigned int flags = 0;
	113	u32 v;
	114
	115	if (!fwnode_property_read_u32(fwnode, "hsync-active", &v))
	116	flags \|= v ? V4L2_MBUS_HSYNC_ACTIVE_HIGH :
	117	V4L2_MBUS_HSYNC_ACTIVE_LOW;
	118
	119	if (!fwnode_property_read_u32(fwnode, "vsync-active", &v))
	120	flags \|= v ? V4L2_MBUS_VSYNC_ACTIVE_HIGH :
	121	V4L2_MBUS_VSYNC_ACTIVE_LOW;
	122
	123	if (!fwnode_property_read_u32(fwnode, "field-even-active", &v))
	124	flags \|= v ? V4L2_MBUS_FIELD_EVEN_HIGH :
	125	V4L2_MBUS_FIELD_EVEN_LOW;
	126	if (flags)
	127	vep->bus_type = V4L2_MBUS_PARALLEL;
	128	else
	129	vep->bus_type = V4L2_MBUS_BT656;
	130
	131	if (!fwnode_property_read_u32(fwnode, "pclk-sample", &v))
	132	flags \|= v ? V4L2_MBUS_PCLK_SAMPLE_RISING :
	133	V4L2_MBUS_PCLK_SAMPLE_FALLING;
	134
	135	if (!fwnode_property_read_u32(fwnode, "data-active", &v))
	136	flags \|= v ? V4L2_MBUS_DATA_ACTIVE_HIGH :
	137	V4L2_MBUS_DATA_ACTIVE_LOW;
	138
	139	if (fwnode_property_present(fwnode, "slave-mode"))
	140	flags \|= V4L2_MBUS_SLAVE;
	141	else
	142	flags \|= V4L2_MBUS_MASTER;
	143
	144	if (!fwnode_property_read_u32(fwnode, "bus-width", &v))
	145	bus->bus_width = v;
	146
	147	if (!fwnode_property_read_u32(fwnode, "data-shift", &v))
	148	bus->data_shift = v;
	149
150	if (!fwnode_property_read_u32(fwnode, "sync-on-green-active", &v))
151	flags \|= v ? V4L2_MBUS_VIDEO_SOG_ACTIVE_HIGH :
152	V4L2_MBUS_VIDEO_SOG_ACTIVE_LOW;
153
154	bus->flags = flags;
155
156	}
157
abc5b2cb MCC	158	static void
	159	v4l2_fwnode_endpoint_parse_csi1_bus(struct fwnode_handle *fwnode,
	160	struct v4l2_fwnode_endpoint *vep,
	161	u32 bus_type)
97bbdf02 SA	162	{
	163	struct v4l2_fwnode_bus_mipi_csi1 *bus = &vep->bus.mipi_csi1;
	164	u32 v;
	165
	166	if (!fwnode_property_read_u32(fwnode, "clock-inv", &v))
	167	bus->clock_inv = v;
	168
	169	if (!fwnode_property_read_u32(fwnode, "strobe", &v))
	170	bus->strobe = v;
	171
	172	if (!fwnode_property_read_u32(fwnode, "data-lanes", &v))
	173	bus->data_lane = v;
	174
	175	if (!fwnode_property_read_u32(fwnode, "clock-lanes", &v))
	176	bus->clock_lane = v;
	177
	178	if (bus_type == V4L2_FWNODE_BUS_TYPE_CCP2)
	179	vep->bus_type = V4L2_MBUS_CCP2;
	180	else
	181	vep->bus_type = V4L2_MBUS_CSI1;
	182	}
	183
ca50c197 SA	184	/**
	185	* v4l2_fwnode_endpoint_parse() - parse all fwnode node properties
	186	* @fwnode: pointer to the endpoint's fwnode handle
	187	* @vep: pointer to the V4L2 fwnode data structure
	188	*
	189	* All properties are optional. If none are found, we don't set any flags. This
	190	* means the port has a static configuration and no properties have to be
	191	* specified explicitly. If any properties that identify the bus as parallel
	192	* are found and slave-mode isn't set, we set V4L2_MBUS_MASTER. Similarly, if
	193	* we recognise the bus as serial CSI-2 and clock-noncontinuous isn't set, we
	194	* set the V4L2_MBUS_CSI2_CONTINUOUS_CLOCK flag. The caller should hold a
	195	* reference to @fwnode.
	196	*
	197	* NOTE: This function does not parse properties the size of which is variable
	198	* without a low fixed limit. Please use v4l2_fwnode_endpoint_alloc_parse() in
	199	* new drivers instead.
	200	*
	201	* Return: 0 on success or a negative error code on failure.
	202	*/
	203	int v4l2_fwnode_endpoint_parse(struct fwnode_handle *fwnode,
	204	struct v4l2_fwnode_endpoint *vep)
	205	{
e07a41f9	206	u32 bus_type = 0;
ca50c197 SA	207	int rval;
	208
	209	fwnode_graph_parse_endpoint(fwnode, &vep->base);
	210
	211	/* Zero fields from bus_type to until the end */
	212	memset(&vep->bus_type, 0, sizeof(*vep) -
	213	offsetof(typeof(*vep), bus_type));
	214
e07a41f9 SA	215	fwnode_property_read_u32(fwnode, "bus-type", &bus_type);
e07a41f9 SA	216
97bbdf02 SA	217	switch (bus_type) {
	218	case V4L2_FWNODE_BUS_TYPE_GUESS:
	219	rval = v4l2_fwnode_endpoint_parse_csi2_bus(fwnode, vep);
	220	if (rval)
	221	return rval;
	222	/*
	223	* Parse the parallel video bus properties only if none
	224	* of the MIPI CSI-2 specific properties were found.
	225	*/
	226	if (vep->bus.mipi_csi2.flags == 0)
	227	v4l2_fwnode_endpoint_parse_parallel_bus(fwnode, vep);
	228
	229	return 0;
	230	case V4L2_FWNODE_BUS_TYPE_CCP2:
	231	case V4L2_FWNODE_BUS_TYPE_CSI1:
	232	v4l2_fwnode_endpoint_parse_csi1_bus(fwnode, vep, bus_type);
	233
	234	return 0;
	235	default:
	236	pr_warn("unsupported bus type %u\n", bus_type);
	237	return -EINVAL;
	238	}
ca50c197 SA	239	}
	240	EXPORT_SYMBOL_GPL(v4l2_fwnode_endpoint_parse);
	241
	242	/*
	243	* v4l2_fwnode_endpoint_free() - free the V4L2 fwnode acquired by
	244	* v4l2_fwnode_endpoint_alloc_parse()
	245	* @vep - the V4L2 fwnode the resources of which are to be released
	246	*
	247	* It is safe to call this function with NULL argument or on a V4L2 fwnode the
	248	* parsing of which failed.
	249	*/
	250	void v4l2_fwnode_endpoint_free(struct v4l2_fwnode_endpoint *vep)
	251	{
	252	if (IS_ERR_OR_NULL(vep))
	253	return;
	254
	255	kfree(vep->link_frequencies);
	256	kfree(vep);
	257	}
	258	EXPORT_SYMBOL_GPL(v4l2_fwnode_endpoint_free);
	259
	260	/**
	261	* v4l2_fwnode_endpoint_alloc_parse() - parse all fwnode node properties
	262	* @fwnode: pointer to the endpoint's fwnode handle
	263	*
	264	* All properties are optional. If none are found, we don't set any flags. This
	265	* means the port has a static configuration and no properties have to be
	266	* specified explicitly. If any properties that identify the bus as parallel
	267	* are found and slave-mode isn't set, we set V4L2_MBUS_MASTER. Similarly, if
	268	* we recognise the bus as serial CSI-2 and clock-noncontinuous isn't set, we
	269	* set the V4L2_MBUS_CSI2_CONTINUOUS_CLOCK flag. The caller should hold a
	270	* reference to @fwnode.
	271	*
	272	* v4l2_fwnode_endpoint_alloc_parse() has two important differences to
	273	* v4l2_fwnode_endpoint_parse():
	274	*
	275	* 1. It also parses variable size data.
	276	*
	277	* 2. The memory it has allocated to store the variable size data must be freed
	278	* using v4l2_fwnode_endpoint_free() when no longer needed.
	279	*
	280	* Return: Pointer to v4l2_fwnode_endpoint if successful, on an error pointer
	281	* on error.
	282	*/
	283	struct v4l2_fwnode_endpoint *v4l2_fwnode_endpoint_alloc_parse(
	284	struct fwnode_handle *fwnode)
	285	{
	286	struct v4l2_fwnode_endpoint *vep;
	287	int rval;
	288
	289	vep = kzalloc(sizeof(*vep), GFP_KERNEL);
	290	if (!vep)
	291	return ERR_PTR(-ENOMEM);
	292
	293	rval = v4l2_fwnode_endpoint_parse(fwnode, vep);
	294	if (rval < 0)
	295	goto out_err;
	296
	297	rval = fwnode_property_read_u64_array(fwnode, "link-frequencies",
	298	NULL, 0);
06f81520 SA	299	if (rval > 0) {
	300	vep->link_frequencies =
	301	kmalloc_array(rval, sizeof(*vep->link_frequencies),
	302	GFP_KERNEL);
	303	if (!vep->link_frequencies) {
	304	rval = -ENOMEM;
	305	goto out_err;
	306	}
ca50c197	307
06f81520	308	vep->nr_of_link_frequencies = rval;
ca50c197	309
06f81520 SA	310	rval = fwnode_property_read_u64_array(
	311	fwnode, "link-frequencies", vep->link_frequencies,
	312	vep->nr_of_link_frequencies);
	313	if (rval < 0)
	314	goto out_err;
	315	}
ca50c197 SA	316
	317	return vep;
	318
	319	out_err:
	320	v4l2_fwnode_endpoint_free(vep);
	321	return ERR_PTR(rval);
	322	}
	323	EXPORT_SYMBOL_GPL(v4l2_fwnode_endpoint_alloc_parse);
	324
	325	/**
	326	* v4l2_fwnode_endpoint_parse_link() - parse a link between two endpoints
	327	* @__fwnode: pointer to the endpoint's fwnode at the local end of the link
	328	* @link: pointer to the V4L2 fwnode link data structure
	329	*
	330	* Fill the link structure with the local and remote nodes and port numbers.
	331	* The local_node and remote_node fields are set to point to the local and
	332	* remote port's parent nodes respectively (the port parent node being the
	333	* parent node of the port node if that node isn't a 'ports' node, or the
	334	* grand-parent node of the port node otherwise).
	335	*
	336	* A reference is taken to both the local and remote nodes, the caller must use
	337	* v4l2_fwnode_endpoint_put_link() to drop the references when done with the
	338	* link.
	339	*
	340	* Return: 0 on success, or -ENOLINK if the remote endpoint fwnode can't be
	341	* found.
	342	*/
	343	int v4l2_fwnode_parse_link(struct fwnode_handle *__fwnode,
	344	struct v4l2_fwnode_link *link)
	345	{
	346	const char *port_prop = is_of_node(__fwnode) ? "reg" : "port";
	347	struct fwnode_handle *fwnode;
	348
	349	memset(link, 0, sizeof(*link));
	350
	351	fwnode = fwnode_get_parent(__fwnode);
	352	fwnode_property_read_u32(fwnode, port_prop, &link->local_port);
	353	fwnode = fwnode_get_next_parent(fwnode);
	354	if (is_of_node(fwnode) &&
	355	of_node_cmp(to_of_node(fwnode)->name, "ports") == 0)
	356	fwnode = fwnode_get_next_parent(fwnode);
	357	link->local_node = fwnode;
	358
	359	fwnode = fwnode_graph_get_remote_endpoint(__fwnode);
	360	if (!fwnode) {
	361	fwnode_handle_put(fwnode);
	362	return -ENOLINK;
	363	}
	364
	365	fwnode = fwnode_get_parent(fwnode);
	366	fwnode_property_read_u32(fwnode, port_prop, &link->remote_port);
	367	fwnode = fwnode_get_next_parent(fwnode);
	368	if (is_of_node(fwnode) &&
	369	of_node_cmp(to_of_node(fwnode)->name, "ports") == 0)
	370	fwnode = fwnode_get_next_parent(fwnode);
	371	link->remote_node = fwnode;
	372
	373	return 0;
	374	}
	375	EXPORT_SYMBOL_GPL(v4l2_fwnode_parse_link);
	376
	377	/**
	378	* v4l2_fwnode_put_link() - drop references to nodes in a link
	379	* @link: pointer to the V4L2 fwnode link data structure
380	*
381	* Drop references to the local and remote nodes in the link. This function
382	* must be called on every link parsed with v4l2_fwnode_parse_link().
383	*/
384	void v4l2_fwnode_put_link(struct v4l2_fwnode_link *link)
385	{
386	fwnode_handle_put(link->local_node);
387	fwnode_handle_put(link->remote_node);
388	}
389	EXPORT_SYMBOL_GPL(v4l2_fwnode_put_link);
390
391	MODULE_LICENSE("GPL");
392	MODULE_AUTHOR("Sakari Ailus <sakari.ailus@linux.intel.com>");
393	MODULE_AUTHOR("Sylwester Nawrocki <s.nawrocki@samsung.com>");
394	MODULE_AUTHOR("Guennadi Liakhovetski <g.liakhovetski@gmx.de>");