1 #include <linux/component.h> 2 #include <linux/export.h> 3 #include <linux/list.h> 4 #include <linux/of_graph.h> 5 #include <drm/drmP.h> 6 #include <drm/drm_crtc.h> 7 #include <drm/drm_of.h> 8 9 /** 10 * drm_crtc_port_mask - find the mask of a registered CRTC by port OF node 11 * @dev: DRM device 12 * @port: port OF node 13 * 14 * Given a port OF node, return the possible mask of the corresponding 15 * CRTC within a device's list of CRTCs. Returns zero if not found. 16 */ 17 static uint32_t drm_crtc_port_mask(struct drm_device *dev, 18 struct device_node *port) 19 { 20 unsigned int index = 0; 21 struct drm_crtc *tmp; 22 23 drm_for_each_crtc(tmp, dev) { 24 if (tmp->port == port) 25 return 1 << index; 26 27 index++; 28 } 29 30 return 0; 31 } 32 33 /** 34 * drm_of_find_possible_crtcs - find the possible CRTCs for an encoder port 35 * @dev: DRM device 36 * @port: encoder port to scan for endpoints 37 * 38 * Scan all endpoints attached to a port, locate their attached CRTCs, 39 * and generate the DRM mask of CRTCs which may be attached to this 40 * encoder. 41 * 42 * See Documentation/devicetree/bindings/graph.txt for the bindings. 43 */ 44 uint32_t drm_of_find_possible_crtcs(struct drm_device *dev, 45 struct device_node *port) 46 { 47 struct device_node *remote_port, *ep; 48 uint32_t possible_crtcs = 0; 49 50 for_each_endpoint_of_node(port, ep) { 51 remote_port = of_graph_get_remote_port(ep); 52 if (!remote_port) { 53 of_node_put(ep); 54 return 0; 55 } 56 57 possible_crtcs |= drm_crtc_port_mask(dev, remote_port); 58 59 of_node_put(remote_port); 60 } 61 62 return possible_crtcs; 63 } 64 EXPORT_SYMBOL(drm_of_find_possible_crtcs); 65 66 /** 67 * drm_of_component_probe - Generic probe function for a component based master 68 * @dev: master device containing the OF node 69 * @compare_of: compare function used for matching components 70 * @master_ops: component master ops to be used 71 * 72 * Parse the platform device OF node and bind all the components associated 73 * with the master. Interface ports are added before the encoders in order to 74 * satisfy their .bind requirements 75 * See Documentation/devicetree/bindings/graph.txt for the bindings. 76 * 77 * Returns zero if successful, or one of the standard error codes if it fails. 78 */ 79 int drm_of_component_probe(struct device *dev, 80 int (*compare_of)(struct device *, void *), 81 const struct component_master_ops *m_ops) 82 { 83 struct device_node *ep, *port, *remote; 84 struct component_match *match = NULL; 85 int i; 86 87 if (!dev->of_node) 88 return -EINVAL; 89 90 /* 91 * Bind the crtc's ports first, so that drm_of_find_possible_crtcs() 92 * called from encoder's .bind callbacks works as expected 93 */ 94 for (i = 0; ; i++) { 95 port = of_parse_phandle(dev->of_node, "ports", i); 96 if (!port) 97 break; 98 99 if (!of_device_is_available(port->parent)) { 100 of_node_put(port); 101 continue; 102 } 103 104 component_match_add(dev, &match, compare_of, port); 105 of_node_put(port); 106 } 107 108 if (i == 0) { 109 dev_err(dev, "missing 'ports' property\n"); 110 return -ENODEV; 111 } 112 113 if (!match) { 114 dev_err(dev, "no available port\n"); 115 return -ENODEV; 116 } 117 118 /* 119 * For bound crtcs, bind the encoders attached to their remote endpoint 120 */ 121 for (i = 0; ; i++) { 122 port = of_parse_phandle(dev->of_node, "ports", i); 123 if (!port) 124 break; 125 126 if (!of_device_is_available(port->parent)) { 127 of_node_put(port); 128 continue; 129 } 130 131 for_each_child_of_node(port, ep) { 132 remote = of_graph_get_remote_port_parent(ep); 133 if (!remote || !of_device_is_available(remote)) { 134 of_node_put(remote); 135 continue; 136 } else if (!of_device_is_available(remote->parent)) { 137 dev_warn(dev, "parent device of %s is not available\n", 138 remote->full_name); 139 of_node_put(remote); 140 continue; 141 } 142 143 component_match_add(dev, &match, compare_of, remote); 144 of_node_put(remote); 145 } 146 of_node_put(port); 147 } 148 149 return component_master_add_with_match(dev, m_ops, match); 150 } 151 EXPORT_SYMBOL(drm_of_component_probe); 152 153 /* 154 * drm_of_encoder_active_endpoint - return the active encoder endpoint 155 * @node: device tree node containing encoder input ports 156 * @encoder: drm_encoder 157 * 158 * Given an encoder device node and a drm_encoder with a connected crtc, 159 * parse the encoder endpoint connecting to the crtc port. 160 */ 161 int drm_of_encoder_active_endpoint(struct device_node *node, 162 struct drm_encoder *encoder, 163 struct of_endpoint *endpoint) 164 { 165 struct device_node *ep; 166 struct drm_crtc *crtc = encoder->crtc; 167 struct device_node *port; 168 int ret; 169 170 if (!node || !crtc) 171 return -EINVAL; 172 173 for_each_endpoint_of_node(node, ep) { 174 port = of_graph_get_remote_port(ep); 175 of_node_put(port); 176 if (port == crtc->port) { 177 ret = of_graph_parse_endpoint(ep, endpoint); 178 of_node_put(ep); 179 return ret; 180 } 181 } 182 183 return -EINVAL; 184 } 185 EXPORT_SYMBOL_GPL(drm_of_encoder_active_endpoint); 186