linux/drivers/media/v4l2-core/v4l2-fwnode.c

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/*
* 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>");