// SPDX-License-Identifier: GPL-2.0-only
#include <linux/component.h>
#include <linux/export.h>
#include <linux/list.h>
#include <linux/media-bus-format.h>
#include <linux/of.h>
#include <linux/of_graph.h>
#include <drm/drm_bridge.h>
#include <drm/drm_crtc.h>
#include <drm/drm_device.h>
#include <drm/drm_encoder.h>
#include <drm/drm_mipi_dsi.h>
#include <drm/drm_of.h>
#include <drm/drm_panel.h>
/**
* DOC: overview
*
* A set of helper functions to aid DRM drivers in parsing standard DT
* properties.
*/
/**
* drm_of_crtc_port_mask - find the mask of a registered CRTC by port OF node
* @dev: DRM device
* @port: port OF node
*
* Given a port OF node, return the possible mask of the corresponding
* CRTC within a device's list of CRTCs. Returns zero if not found.
*/
uint32_t drm_of_crtc_port_mask(struct drm_device *dev,
struct device_node *port)
{
unsigned int index = 0;
struct drm_crtc *tmp;
drm_for_each_crtc(tmp, dev) {
if (tmp->port == port)
return 1 << index;
index++;
}
return 0;
}
EXPORT_SYMBOL(drm_of_crtc_port_mask);
/**
* drm_of_find_possible_crtcs - find the possible CRTCs for an encoder port
* @dev: DRM device
* @port: encoder port to scan for endpoints
*
* Scan all endpoints attached to a port, locate their attached CRTCs,
* and generate the DRM mask of CRTCs which may be attached to this
* encoder.
*
* See Documentation/devicetree/bindings/graph.txt for the bindings.
*/
uint32_t drm_of_find_possible_crtcs(struct drm_device *dev,
struct device_node *port)
{
struct device_node *remote_port, *ep;
uint32_t possible_crtcs = 0;
for_each_endpoint_of_node(port, ep) {
remote_port = of_graph_get_remote_port(ep);
if (!remote_port) {
of_node_put(ep);
return 0;
}
possible_crtcs |= drm_of_crtc_port_mask(dev, remote_port);
of_node_put(remote_port);
}
return possible_crtcs;
}
EXPORT_SYMBOL(drm_of_find_possible_crtcs);
/**
* drm_of_component_match_add - Add a component helper OF node match rule
* @master: master device
* @matchptr: component match pointer
* @compare: compare function used for matching component
* @node: of_node
*/
void drm_of_component_match_add(struct device *master,
struct component_match **matchptr,
int (*compare)(struct device *, void *),
struct device_node *node)
{
of_node_get(node);
component_match_add_release(master, matchptr, component_release_of,
compare, node);
}
EXPORT_SYMBOL_GPL(drm_of_component_match_add);
/**
* drm_of_component_probe - Generic probe function for a component based master
* @dev: master device containing the OF node
* @compare_of: compare function used for matching components
* @m_ops: component master ops to be used
*
* Parse the platform device OF node and bind all the components associated
* with the master. Interface ports are added before the encoders in order to
* satisfy their .bind requirements
* See Documentation/devicetree/bindings/graph.txt for the bindings.
*
* Returns zero if successful, or one of the standard error codes if it fails.
*/
int drm_of_component_probe(struct device *dev,
int (*compare_of)(struct device *, void *),
const struct component_master_ops *m_ops)
{
struct device_node *ep, *port, *remote;
struct component_match *match = NULL;
int i;
if (!dev->of_node)
return -EINVAL;
/*
* Bind the crtc's ports first, so that drm_of_find_possible_crtcs()
* called from encoder's .bind callbacks works as expected
*/
for (i = 0; ; i++) {
port = of_parse_phandle(dev->of_node, "ports", i);
if (!port)
break;
if (of_device_is_available(port->parent))
drm_of_component_match_add(dev, &match, compare_of,
port);
of_node_put(port);
}
if (i == 0) {
dev_err(dev, "missing 'ports' property\n");
return -ENODEV;
}
if (!match) {
dev_err(dev, "no available port\n");
return -ENODEV;
}
/*
* For bound crtcs, bind the encoders attached to their remote endpoint
*/
for (i = 0; ; i++) {
port = of_parse_phandle(dev->of_node, "ports", i);
if (!port)
break;
if (!of_device_is_available(port->parent)) {
of_node_put(port);
continue;
}
for_each_child_of_node(port, ep) {
remote = of_graph_get_remote_port_parent(ep);
if (!remote || !of_device_is_available(remote)) {
of_node_put(remote);
continue;
} else if (!of_device_is_available(remote->parent)) {
dev_warn(dev, "parent device of %pOF is not available\n",
remote);
of_node_put(remote);
continue;
}
drm_of_component_match_add(dev, &match, compare_of,
remote);
of_node_put(remote);
}
of_node_put(port);
}
return component_master_add_with_match(dev, m_ops, match);
}
EXPORT_SYMBOL(drm_of_component_probe);
/*
* drm_of_encoder_active_endpoint - return the active encoder endpoint
* @node: device tree node containing encoder input ports
* @encoder: drm_encoder
*
* Given an encoder device node and a drm_encoder with a connected crtc,
* parse the encoder endpoint connecting to the crtc port.
*/
int drm_of_encoder_active_endpoint(struct device_node *node,
struct drm_encoder *encoder,
struct of_endpoint *endpoint)
{
struct device_node *ep;
struct drm_crtc *crtc = encoder->crtc;
struct device_node *port;
int ret;
if (!node || !crtc)
return -EINVAL;
for_each_endpoint_of_node(node, ep) {
port = of_graph_get_remote_port(ep);
of_node_put(port);
if (port == crtc->port) {
ret = of_graph_parse_endpoint(ep, endpoint);
of_node_put(ep);
return ret;
}
}
return -EINVAL;
}
EXPORT_SYMBOL_GPL(drm_of_encoder_active_endpoint);
/**
* drm_of_find_panel_or_bridge - return connected panel or bridge device
* @np: device tree node containing encoder output ports
* @port: port in the device tree node
* @endpoint: endpoint in the device tree node
* @panel: pointer to hold returned drm_panel
* @bridge: pointer to hold returned drm_bridge
*
* Given a DT node's port and endpoint number, find the connected node and
* return either the associated struct drm_panel or drm_bridge device. Either
* @panel or @bridge must not be NULL.
*
* This function is deprecated and should not be used in new drivers. Use
* devm_drm_of_get_bridge() instead.
*
* Returns zero if successful, or one of the standard error codes if it fails.
*/
int drm_of_find_panel_or_bridge(const struct device_node *np,
int port, int endpoint,
struct drm_panel **panel,
struct drm_bridge **bridge)
{
int ret = -EPROBE_DEFER;
struct device_node *remote;
if (!panel && !bridge)
return -EINVAL;
if (panel)
*panel = NULL;
/*
* of_graph_get_remote_node() produces a noisy error message if port
* node isn't found and the absence of the port is a legit case here,
* so at first we silently check whether graph presents in the
* device-tree node.
*/
if (!of_graph_is_present(np))
return -ENODEV;
remote = of_graph_get_remote_node(np, port, endpoint);
if (!remote)
return -ENODEV;
if (panel) {
*panel = of_drm_find_panel(remote);
if (!IS_ERR(*panel))
ret = 0;
else
*panel = NULL;
}
/* No panel found yet, check for a bridge next. */
if (bridge) {
if (ret) {
*bridge = of_drm_find_bridge(remote);
if (*bridge)
ret = 0;
} else {
*bridge = NULL;
}
}
of_node_put(remote);
return ret;
}
EXPORT_SYMBOL_GPL(drm_of_find_panel_or_bridge);
enum drm_of_lvds_pixels {
DRM_OF_LVDS_EVEN = BIT(0),
DRM_OF_LVDS_ODD = BIT(1),
};
static int drm_of_lvds_get_port_pixels_type(struct device_node *port_node)
{
bool even_pixels =
of_property_read_bool(port_node, "dual-lvds-even-pixels");
bool odd_pixels =
of_property_read_bool(port_node, "dual-lvds-odd-pixels");
return (even_pixels ? DRM_OF_LVDS_EVEN : 0) |
(odd_pixels ? DRM_OF_LVDS_ODD : 0);
}
static int drm_of_lvds_get_remote_pixels_type(
const struct device_node *port_node)
{
struct device_node *endpoint = NULL;
int pixels_type = -EPIPE;
for_each_child_of_node(port_node, endpoint) {
struct device_node *remote_port;
int current_pt;
if (!of_node_name_eq(endpoint, "endpoint"))
continue;
remote_port = of_graph_get_remote_port(endpoint);
if (!remote_port) {
of_node_put(endpoint);
return -EPIPE;
}
current_pt = drm_of_lvds_get_port_pixels_type(remote_port);
of_node_put(remote_port);
if (pixels_type < 0)
pixels_type = current_pt;
/*
* Sanity check, ensure that all remote endpoints have the same
* pixel type. We may lift this restriction later if we need to
* support multiple sinks with different dual-link
* configurations by passing the endpoints explicitly to
* drm_of_lvds_get_dual_link_pixel_order().
*/
if (!current_pt || pixels_type != current_pt) {
of_node_put(endpoint);
return -EINVAL;
}
}
return pixels_type;
}
/**
* drm_of_lvds_get_dual_link_pixel_order - Get LVDS dual-link pixel order
* @port1: First DT port node of the Dual-link LVDS source
* @port2: Second DT port node of the Dual-link LVDS source
*
* An LVDS dual-link connection is made of two links, with even pixels
* transitting on one link, and odd pixels on the other link. This function
* returns, for two ports of an LVDS dual-link source, which port shall transmit
* the even and odd pixels, based on the requirements of the connected sink.
*
* The pixel order is determined from the dual-lvds-even-pixels and
* dual-lvds-odd-pixels properties in the sink's DT port nodes. If those
* properties are not present, or if their usage is not valid, this function
* returns -EINVAL.
*
* If either port is not connected, this function returns -EPIPE.
*
* @port1 and @port2 are typically DT sibling nodes, but may have different
* parents when, for instance, two separate LVDS encoders carry the even and odd
* pixels.
*
* Return:
* * DRM_LVDS_DUAL_LINK_EVEN_ODD_PIXELS - @port1 carries even pixels and @port2
* carries odd pixels
* * DRM_LVDS_DUAL_LINK_ODD_EVEN_PIXELS - @port1 carries odd pixels and @port2
* carries even pixels
* * -EINVAL - @port1 and @port2 are not connected to a dual-link LVDS sink, or
* the sink configuration is invalid
* * -EPIPE - when @port1 or @port2 are not connected
*/
int drm_of_lvds_get_dual_link_pixel_order(const struct device_node *port1,
const struct device_node *port2)
{
int remote_p1_pt, remote_p2_pt;
if (!port1 || !port2)
return -EINVAL;
remote_p1_pt = drm_of_lvds_get_remote_pixels_type(port1);
if (remote_p1_pt < 0)
return remote_p1_pt;
remote_p2_pt = drm_of_lvds_get_remote_pixels_type(port2);
if (remote_p2_pt < 0)
return remote_p2_pt;
/*
* A valid dual-lVDS bus is found when one remote port is marked with
* "dual-lvds-even-pixels", and the other remote port is marked with
* "dual-lvds-odd-pixels", bail out if the markers are not right.
*/
if (remote_p1_pt + remote_p2_pt != DRM_OF_LVDS_EVEN + DRM_OF_LVDS_ODD)
return -EINVAL;
return remote_p1_pt == DRM_OF_LVDS_EVEN ?
DRM_LVDS_DUAL_LINK_EVEN_ODD_PIXELS :
DRM_LVDS_DUAL_LINK_ODD_EVEN_PIXELS;
}
EXPORT_SYMBOL_GPL(drm_of_lvds_get_dual_link_pixel_order);
/**
* drm_of_lvds_get_data_mapping - Get LVDS data mapping
* @port: DT port node of the LVDS source or sink
*
* Convert DT "data-mapping" property string value into media bus format value.
*
* Return:
* * MEDIA_BUS_FMT_RGB666_1X7X3_SPWG - data-mapping is "jeida-18"
* * MEDIA_BUS_FMT_RGB888_1X7X4_JEIDA - data-mapping is "jeida-24"
* * MEDIA_BUS_FMT_RGB888_1X7X4_SPWG - data-mapping is "vesa-24"
* * -EINVAL - the "data-mapping" property is unsupported
* * -ENODEV - the "data-mapping" property is missing
*/
int drm_of_lvds_get_data_mapping(const struct device_node *port)
{
const char *mapping;
int ret;
ret = of_property_read_string(port, "data-mapping", &mapping);
if (ret < 0)
return -ENODEV;
if (!strcmp(mapping, "jeida-18"))
return MEDIA_BUS_FMT_RGB666_1X7X3_SPWG;
if (!strcmp(mapping, "jeida-24"))
return MEDIA_BUS_FMT_RGB888_1X7X4_JEIDA;
if (!strcmp(mapping, "vesa-24"))
return MEDIA_BUS_FMT_RGB888_1X7X4_SPWG;
return -EINVAL;
}
EXPORT_SYMBOL_GPL(drm_of_lvds_get_data_mapping);
/**
* drm_of_get_data_lanes_count - Get DSI/(e)DP data lane count
* @endpoint: DT endpoint node of the DSI/(e)DP source or sink
* @min: minimum supported number of data lanes
* @max: maximum supported number of data lanes
*
* Count DT "data-lanes" property elements and check for validity.
*
* Return:
* * min..max - positive integer count of "data-lanes" elements
* * -ve - the "data-lanes" property is missing or invalid
* * -EINVAL - the "data-lanes" property is unsupported
*/
int drm_of_get_data_lanes_count(const struct device_node *endpoint,
const unsigned int min, const unsigned int max)
{
int ret;
ret = of_property_count_u32_elems(endpoint, "data-lanes");
if (ret < 0)
return ret;
if (ret < min || ret > max)
return -EINVAL;
return ret;
}
EXPORT_SYMBOL_GPL(drm_of_get_data_lanes_count);
/**
* drm_of_get_data_lanes_count_ep - Get DSI/(e)DP data lane count by endpoint
* @port: DT port node of the DSI/(e)DP source or sink
* @port_reg: identifier (value of reg property) of the parent port node
* @reg: identifier (value of reg property) of the endpoint node
* @min: minimum supported number of data lanes
* @max: maximum supported number of data lanes
*
* Count DT "data-lanes" property elements and check for validity.
* This variant uses endpoint specifier.
*
* Return:
* * min..max - positive integer count of "data-lanes" elements
* * -EINVAL - the "data-mapping" property is unsupported
* * -ENODEV - the "data-mapping" property is missing
*/
int drm_of_get_data_lanes_count_ep(const struct device_node *port,
int port_reg, int reg,
const unsigned int min,
const unsigned int max)
{
struct device_node *endpoint;
int ret;
endpoint = of_graph_get_endpoint_by_regs(port, port_reg, reg);
ret = drm_of_get_data_lanes_count(endpoint, min, max);
of_node_put(endpoint);
return ret;
}
EXPORT_SYMBOL_GPL(drm_of_get_data_lanes_count_ep);
#if IS_ENABLED(CONFIG_DRM_MIPI_DSI)
/**
* drm_of_get_dsi_bus - find the DSI bus for a given device
* @dev: parent device of display (SPI, I2C)
*
* Gets parent DSI bus for a DSI device controlled through a bus other
* than MIPI-DCS (SPI, I2C, etc.) using the Device Tree.
*
* Returns pointer to mipi_dsi_host if successful, -EINVAL if the
* request is unsupported, -EPROBE_DEFER if the DSI host is found but
* not available, or -ENODEV otherwise.
*/
struct mipi_dsi_host *drm_of_get_dsi_bus(struct device *dev)
{
struct mipi_dsi_host *dsi_host;
struct device_node *endpoint, *dsi_host_node;
/*
* Get first endpoint child from device.
*/
endpoint = of_graph_get_next_endpoint(dev->of_node, NULL);
if (!endpoint)
return ERR_PTR(-ENODEV);
/*
* Follow the first endpoint to get the DSI host node and then
* release the endpoint since we no longer need it.
*/
dsi_host_node = of_graph_get_remote_port_parent(endpoint);
of_node_put(endpoint);
if (!dsi_host_node)
return ERR_PTR(-ENODEV);
/*
* Get the DSI host from the DSI host node. If we get an error
* or the return is null assume we're not ready to probe just
* yet. Release the DSI host node since we're done with it.
*/
dsi_host = of_find_mipi_dsi_host_by_node(dsi_host_node);
of_node_put(dsi_host_node);
if (IS_ERR_OR_NULL(dsi_host))
return ERR_PTR(-EPROBE_DEFER);
return dsi_host;
}
EXPORT_SYMBOL_GPL(drm_of_get_dsi_bus);
#endif /* CONFIG_DRM_MIPI_DSI */
