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authorLibravatar Linus Torvalds <torvalds@linux-foundation.org>2023-02-21 18:24:12 -0800
committerLibravatar Linus Torvalds <torvalds@linux-foundation.org>2023-02-21 18:24:12 -0800
commit5b7c4cabbb65f5c469464da6c5f614cbd7f730f2 (patch)
treecc5c2d0a898769fd59549594fedb3ee6f84e59a0 /drivers/gpu/drm/drm_of.c
downloadlinux-5b7c4cabbb65f5c469464da6c5f614cbd7f730f2.tar.gz
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Merge tag 'net-next-6.3' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-nextgrafted
Pull networking updates from Jakub Kicinski: "Core: - Add dedicated kmem_cache for typical/small skb->head, avoid having to access struct page at kfree time, and improve memory use. - Introduce sysctl to set default RPS configuration for new netdevs. - Define Netlink protocol specification format which can be used to describe messages used by each family and auto-generate parsers. Add tools for generating kernel data structures and uAPI headers. - Expose all net/core sysctls inside netns. - Remove 4s sleep in netpoll if carrier is instantly detected on boot. - Add configurable limit of MDB entries per port, and port-vlan. - Continue populating drop reasons throughout the stack. - Retire a handful of legacy Qdiscs and classifiers. Protocols: - Support IPv4 big TCP (TSO frames larger than 64kB). - Add IP_LOCAL_PORT_RANGE socket option, to control local port range on socket by socket basis. - Track and report in procfs number of MPTCP sockets used. - Support mixing IPv4 and IPv6 flows in the in-kernel MPTCP path manager. - IPv6: don't check net.ipv6.route.max_size and rely on garbage collection to free memory (similarly to IPv4). - Support Penultimate Segment Pop (PSP) flavor in SRv6 (RFC8986). - ICMP: add per-rate limit counters. - Add support for user scanning requests in ieee802154. - Remove static WEP support. - Support minimal Wi-Fi 7 Extremely High Throughput (EHT) rate reporting. - WiFi 7 EHT channel puncturing support (client & AP). BPF: - Add a rbtree data structure following the "next-gen data structure" precedent set by recently added linked list, that is, by using kfunc + kptr instead of adding a new BPF map type. - Expose XDP hints via kfuncs with initial support for RX hash and timestamp metadata. - Add BPF_F_NO_TUNNEL_KEY extension to bpf_skb_set_tunnel_key to better support decap on GRE tunnel devices not operating in collect metadata. - Improve x86 JIT's codegen for PROBE_MEM runtime error checks. - Remove the need for trace_printk_lock for bpf_trace_printk and bpf_trace_vprintk helpers. - Extend libbpf's bpf_tracing.h support for tracing arguments of kprobes/uprobes and syscall as a special case. - Significantly reduce the search time for module symbols by livepatch and BPF. - Enable cpumasks to be used as kptrs, which is useful for tracing programs tracking which tasks end up running on which CPUs in different time intervals. - Add support for BPF trampoline on s390x and riscv64. - Add capability to export the XDP features supported by the NIC. - Add __bpf_kfunc tag for marking kernel functions as kfuncs. - Add cgroup.memory=nobpf kernel parameter option to disable BPF memory accounting for container environments. Netfilter: - Remove the CLUSTERIP target. It has been marked as obsolete for years, and we still have WARN splats wrt races of the out-of-band /proc interface installed by this target. - Add 'destroy' commands to nf_tables. They are identical to the existing 'delete' commands, but do not return an error if the referenced object (set, chain, rule...) did not exist. Driver API: - Improve cpumask_local_spread() locality to help NICs set the right IRQ affinity on AMD platforms. - Separate C22 and C45 MDIO bus transactions more clearly. - Introduce new DCB table to control DSCP rewrite on egress. - Support configuration of Physical Layer Collision Avoidance (PLCA) Reconciliation Sublayer (RS) (802.3cg-2019). Modern version of shared medium Ethernet. - Support for MAC Merge layer (IEEE 802.3-2018 clause 99). Allowing preemption of low priority frames by high priority frames. - Add support for controlling MACSec offload using netlink SET. - Rework devlink instance refcounts to allow registration and de-registration under the instance lock. Split the code into multiple files, drop some of the unnecessarily granular locks and factor out common parts of netlink operation handling. - Add TX frame aggregation parameters (for USB drivers). - Add a new attr TCA_EXT_WARN_MSG to report TC (offload) warning messages with notifications for debug. - Allow offloading of UDP NEW connections via act_ct. - Add support for per action HW stats in TC. - Support hardware miss to TC action (continue processing in SW from a specific point in the action chain). - Warn if old Wireless Extension user space interface is used with modern cfg80211/mac80211 drivers. Do not support Wireless Extensions for Wi-Fi 7 devices at all. Everyone should switch to using nl80211 interface instead. - Improve the CAN bit timing configuration. Use extack to return error messages directly to user space, update the SJW handling, including the definition of a new default value that will benefit CAN-FD controllers, by increasing their oscillator tolerance. New hardware / drivers: - Ethernet: - nVidia BlueField-3 support (control traffic driver) - Ethernet support for imx93 SoCs - Motorcomm yt8531 gigabit Ethernet PHY - onsemi NCN26000 10BASE-T1S PHY (with support for PLCA) - Microchip LAN8841 PHY (incl. cable diagnostics and PTP) - Amlogic gxl MDIO mux - WiFi: - RealTek RTL8188EU (rtl8xxxu) - Qualcomm Wi-Fi 7 devices (ath12k) - CAN: - Renesas R-Car V4H Drivers: - Bluetooth: - Set Per Platform Antenna Gain (PPAG) for Intel controllers. - Ethernet NICs: - Intel (1G, igc): - support TSN / Qbv / packet scheduling features of i226 model - Intel (100G, ice): - use GNSS subsystem instead of TTY - multi-buffer XDP support - extend support for GPIO pins to E823 devices - nVidia/Mellanox: - update the shared buffer configuration on PFC commands - implement PTP adjphase function for HW offset control - TC support for Geneve and GRE with VF tunnel offload - more efficient crypto key management method - multi-port eswitch support - Netronome/Corigine: - add DCB IEEE support - support IPsec offloading for NFP3800 - Freescale/NXP (enetc): - support XDP_REDIRECT for XDP non-linear buffers - improve reconfig, avoid link flap and waiting for idle - support MAC Merge layer - Other NICs: - sfc/ef100: add basic devlink support for ef100 - ionic: rx_push mode operation (writing descriptors via MMIO) - bnxt: use the auxiliary bus abstraction for RDMA - r8169: disable ASPM and reset bus in case of tx timeout - cpsw: support QSGMII mode for J721e CPSW9G - cpts: support pulse-per-second output - ngbe: add an mdio bus driver - usbnet: optimize usbnet_bh() by avoiding unnecessary queuing - r8152: handle devices with FW with NCM support - amd-xgbe: support 10Mbps, 2.5GbE speeds and rx-adaptation - virtio-net: support multi buffer XDP - virtio/vsock: replace virtio_vsock_pkt with sk_buff - tsnep: XDP support - Ethernet high-speed switches: - nVidia/Mellanox (mlxsw): - add support for latency TLV (in FW control messages) - Microchip (sparx5): - separate explicit and implicit traffic forwarding rules, make the implicit rules always active - add support for egress DSCP rewrite - IS0 VCAP support (Ingress Classification) - IS2 VCAP filters (protos, L3 addrs, L4 ports, flags, ToS etc.) - ES2 VCAP support (Egress Access Control) - support for Per-Stream Filtering and Policing (802.1Q, 8.6.5.1) - Ethernet embedded switches: - Marvell (mv88e6xxx): - add MAB (port auth) offload support - enable PTP receive for mv88e6390 - NXP (ocelot): - support MAC Merge layer - support for the the vsc7512 internal copper phys - Microchip: - lan9303: convert to PHYLINK - lan966x: support TC flower filter statistics - lan937x: PTP support for KSZ9563/KSZ8563 and LAN937x - lan937x: support Credit Based Shaper configuration - ksz9477: support Energy Efficient Ethernet - other: - qca8k: convert to regmap read/write API, use bulk operations - rswitch: Improve TX timestamp accuracy - Intel WiFi (iwlwifi): - EHT (Wi-Fi 7) rate reporting - STEP equalizer support: transfer some STEP (connection to radio on platforms with integrated wifi) related parameters from the BIOS to the firmware. - Qualcomm 802.11ax WiFi (ath11k): - IPQ5018 support - Fine Timing Measurement (FTM) responder role support - channel 177 support - MediaTek WiFi (mt76): - per-PHY LED support - mt7996: EHT (Wi-Fi 7) support - Wireless Ethernet Dispatch (WED) reset support - switch to using page pool allocator - RealTek WiFi (rtw89): - support new version of Bluetooth co-existance - Mobile: - rmnet: support TX aggregation" * tag 'net-next-6.3' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next: (1872 commits) page_pool: add a comment explaining the fragment counter usage net: ethtool: fix __ethtool_dev_mm_supported() implementation ethtool: pse-pd: Fix double word in comments xsk: add linux/vmalloc.h to xsk.c sefltests: netdevsim: wait for devlink instance after netns removal selftest: fib_tests: Always cleanup before exit net/mlx5e: Align IPsec ASO result memory to be as required by hardware net/mlx5e: TC, Set CT miss to the specific ct action instance net/mlx5e: Rename CHAIN_TO_REG to MAPPED_OBJ_TO_REG net/mlx5: Refactor tc miss handling to a single function net/mlx5: Kconfig: Make tc offload depend on tc skb extension net/sched: flower: Support hardware miss to tc action net/sched: flower: Move filter handle initialization earlier net/sched: cls_api: Support hardware miss to tc action net/sched: Rename user cookie and act cookie sfc: fix builds without CONFIG_RTC_LIB sfc: clean up some inconsistent indentings net/mlx4_en: Introduce flexible array to silence overflow warning net: lan966x: Fix possible deadlock inside PTP net/ulp: Remove redundant ->clone() test in inet_clone_ulp(). ...
Diffstat (limited to 'drivers/gpu/drm/drm_of.c')
-rw-r--r--drivers/gpu/drm/drm_of.c495
1 files changed, 495 insertions, 0 deletions
diff --git a/drivers/gpu/drm/drm_of.c b/drivers/gpu/drm/drm_of.c
new file mode 100644
index 000000000..7bbcb999b
--- /dev/null
+++ b/drivers/gpu/drm/drm_of.c
@@ -0,0 +1,495 @@
+// 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_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);