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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-05-06 01:02:30 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-05-06 01:02:30 +0000
commit76cb841cb886eef6b3bee341a2266c76578724ad (patch)
treef5892e5ba6cc11949952a6ce4ecbe6d516d6ce58 /drivers/gpu/drm/drm_of.c
parentInitial commit. (diff)
downloadlinux-76cb841cb886eef6b3bee341a2266c76578724ad.tar.xz
linux-76cb841cb886eef6b3bee341a2266c76578724ad.zip
Adding upstream version 4.19.249.upstream/4.19.249
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'drivers/gpu/drm/drm_of.c')
-rw-r--r--drivers/gpu/drm/drm_of.c277
1 files changed, 277 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..2763a5ec8
--- /dev/null
+++ b/drivers/gpu/drm/drm_of.c
@@ -0,0 +1,277 @@
+#include <linux/component.h>
+#include <linux/export.h>
+#include <linux/list.h>
+#include <linux/of_graph.h>
+#include <drm/drmP.h>
+#include <drm/drm_bridge.h>
+#include <drm/drm_crtc.h>
+#include <drm/drm_encoder.h>
+#include <drm/drm_panel.h>
+#include <drm/drm_of.h>
+
+/**
+ * DOC: overview
+ *
+ * A set of helper functions to aid DRM drivers in parsing standard DT
+ * properties.
+ */
+
+static void drm_release_of(struct device *dev, void *data)
+{
+ of_node_put(data);
+}
+
+/**
+ * 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, drm_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
+ * @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.
+ *
+ * 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;
+
+ remote = of_graph_get_remote_node(np, port, endpoint);
+ if (!remote)
+ return -ENODEV;
+
+ if (!of_device_is_available(remote)) {
+ of_node_put(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);