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1// SPDX-License-Identifier: GPL-2.0-only
2#include <linux/component.h>
3#include <linux/export.h>
4#include <linux/list.h>
5#include <linux/of_graph.h>
6
7#include <drm/drm_bridge.h>
8#include <drm/drm_crtc.h>
9#include <drm/drm_device.h>
10#include <drm/drm_encoder.h>
11#include <drm/drm_of.h>
12#include <drm/drm_panel.h>
13
14/**
15 * DOC: overview
16 *
17 * A set of helper functions to aid DRM drivers in parsing standard DT
18 * properties.
19 */
20
21static void drm_release_of(struct device *dev, void *data)
22{
23 of_node_put(data);
24}
25
26/**
27 * drm_of_crtc_port_mask - find the mask of a registered CRTC by port OF node
28 * @dev: DRM device
29 * @port: port OF node
30 *
31 * Given a port OF node, return the possible mask of the corresponding
32 * CRTC within a device's list of CRTCs. Returns zero if not found.
33 */
34uint32_t drm_of_crtc_port_mask(struct drm_device *dev,
35 struct device_node *port)
36{
37 unsigned int index = 0;
38 struct drm_crtc *tmp;
39
40 drm_for_each_crtc(tmp, dev) {
41 if (tmp->port == port)
42 return 1 << index;
43
44 index++;
45 }
46
47 return 0;
48}
49EXPORT_SYMBOL(drm_of_crtc_port_mask);
50
51/**
52 * drm_of_find_possible_crtcs - find the possible CRTCs for an encoder port
53 * @dev: DRM device
54 * @port: encoder port to scan for endpoints
55 *
56 * Scan all endpoints attached to a port, locate their attached CRTCs,
57 * and generate the DRM mask of CRTCs which may be attached to this
58 * encoder.
59 *
60 * See Documentation/devicetree/bindings/graph.txt for the bindings.
61 */
62uint32_t drm_of_find_possible_crtcs(struct drm_device *dev,
63 struct device_node *port)
64{
65 struct device_node *remote_port, *ep;
66 uint32_t possible_crtcs = 0;
67
68 for_each_endpoint_of_node(port, ep) {
69 remote_port = of_graph_get_remote_port(ep);
70 if (!remote_port) {
71 of_node_put(ep);
72 return 0;
73 }
74
75 possible_crtcs |= drm_of_crtc_port_mask(dev, remote_port);
76
77 of_node_put(remote_port);
78 }
79
80 return possible_crtcs;
81}
82EXPORT_SYMBOL(drm_of_find_possible_crtcs);
83
84/**
85 * drm_of_component_match_add - Add a component helper OF node match rule
86 * @master: master device
87 * @matchptr: component match pointer
88 * @compare: compare function used for matching component
89 * @node: of_node
90 */
91void drm_of_component_match_add(struct device *master,
92 struct component_match **matchptr,
93 int (*compare)(struct device *, void *),
94 struct device_node *node)
95{
96 of_node_get(node);
97 component_match_add_release(master, matchptr, drm_release_of,
98 compare, node);
99}
100EXPORT_SYMBOL_GPL(drm_of_component_match_add);
101
102/**
103 * drm_of_component_probe - Generic probe function for a component based master
104 * @dev: master device containing the OF node
105 * @compare_of: compare function used for matching components
106 * @m_ops: component master ops to be used
107 *
108 * Parse the platform device OF node and bind all the components associated
109 * with the master. Interface ports are added before the encoders in order to
110 * satisfy their .bind requirements
111 * See Documentation/devicetree/bindings/graph.txt for the bindings.
112 *
113 * Returns zero if successful, or one of the standard error codes if it fails.
114 */
115int drm_of_component_probe(struct device *dev,
116 int (*compare_of)(struct device *, void *),
117 const struct component_master_ops *m_ops)
118{
119 struct device_node *ep, *port, *remote;
120 struct component_match *match = NULL;
121 int i;
122
123 if (!dev->of_node)
124 return -EINVAL;
125
126 /*
127 * Bind the crtc's ports first, so that drm_of_find_possible_crtcs()
128 * called from encoder's .bind callbacks works as expected
129 */
130 for (i = 0; ; i++) {
131 port = of_parse_phandle(dev->of_node, "ports", i);
132 if (!port)
133 break;
134
135 if (of_device_is_available(port->parent))
136 drm_of_component_match_add(dev, &match, compare_of,
137 port);
138
139 of_node_put(port);
140 }
141
142 if (i == 0) {
143 dev_err(dev, "missing 'ports' property\n");
144 return -ENODEV;
145 }
146
147 if (!match) {
148 dev_err(dev, "no available port\n");
149 return -ENODEV;
150 }
151
152 /*
153 * For bound crtcs, bind the encoders attached to their remote endpoint
154 */
155 for (i = 0; ; i++) {
156 port = of_parse_phandle(dev->of_node, "ports", i);
157 if (!port)
158 break;
159
160 if (!of_device_is_available(port->parent)) {
161 of_node_put(port);
162 continue;
163 }
164
165 for_each_child_of_node(port, ep) {
166 remote = of_graph_get_remote_port_parent(ep);
167 if (!remote || !of_device_is_available(remote)) {
168 of_node_put(remote);
169 continue;
170 } else if (!of_device_is_available(remote->parent)) {
171 dev_warn(dev, "parent device of %pOF is not available\n",
172 remote);
173 of_node_put(remote);
174 continue;
175 }
176
177 drm_of_component_match_add(dev, &match, compare_of,
178 remote);
179 of_node_put(remote);
180 }
181 of_node_put(port);
182 }
183
184 return component_master_add_with_match(dev, m_ops, match);
185}
186EXPORT_SYMBOL(drm_of_component_probe);
187
188/*
189 * drm_of_encoder_active_endpoint - return the active encoder endpoint
190 * @node: device tree node containing encoder input ports
191 * @encoder: drm_encoder
192 *
193 * Given an encoder device node and a drm_encoder with a connected crtc,
194 * parse the encoder endpoint connecting to the crtc port.
195 */
196int drm_of_encoder_active_endpoint(struct device_node *node,
197 struct drm_encoder *encoder,
198 struct of_endpoint *endpoint)
199{
200 struct device_node *ep;
201 struct drm_crtc *crtc = encoder->crtc;
202 struct device_node *port;
203 int ret;
204
205 if (!node || !crtc)
206 return -EINVAL;
207
208 for_each_endpoint_of_node(node, ep) {
209 port = of_graph_get_remote_port(ep);
210 of_node_put(port);
211 if (port == crtc->port) {
212 ret = of_graph_parse_endpoint(ep, endpoint);
213 of_node_put(ep);
214 return ret;
215 }
216 }
217
218 return -EINVAL;
219}
220EXPORT_SYMBOL_GPL(drm_of_encoder_active_endpoint);
221
222/**
223 * drm_of_find_panel_or_bridge - return connected panel or bridge device
224 * @np: device tree node containing encoder output ports
225 * @port: port in the device tree node
226 * @endpoint: endpoint in the device tree node
227 * @panel: pointer to hold returned drm_panel
228 * @bridge: pointer to hold returned drm_bridge
229 *
230 * Given a DT node's port and endpoint number, find the connected node and
231 * return either the associated struct drm_panel or drm_bridge device. Either
232 * @panel or @bridge must not be NULL.
233 *
234 * Returns zero if successful, or one of the standard error codes if it fails.
235 */
236int drm_of_find_panel_or_bridge(const struct device_node *np,
237 int port, int endpoint,
238 struct drm_panel **panel,
239 struct drm_bridge **bridge)
240{
241 int ret = -EPROBE_DEFER;
242 struct device_node *remote;
243
244 if (!panel && !bridge)
245 return -EINVAL;
246 if (panel)
247 *panel = NULL;
248
249 /*
250 * of_graph_get_remote_node() produces a noisy error message if port
251 * node isn't found and the absence of the port is a legit case here,
252 * so at first we silently check whether graph presents in the
253 * device-tree node.
254 */
255 if (!of_graph_is_present(np))
256 return -ENODEV;
257
258 remote = of_graph_get_remote_node(np, port, endpoint);
259 if (!remote)
260 return -ENODEV;
261
262 if (panel) {
263 *panel = of_drm_find_panel(remote);
264 if (!IS_ERR(*panel))
265 ret = 0;
266 else
267 *panel = NULL;
268 }
269
270 /* No panel found yet, check for a bridge next. */
271 if (bridge) {
272 if (ret) {
273 *bridge = of_drm_find_bridge(remote);
274 if (*bridge)
275 ret = 0;
276 } else {
277 *bridge = NULL;
278 }
279
280 }
281
282 of_node_put(remote);
283 return ret;
284}
285EXPORT_SYMBOL_GPL(drm_of_find_panel_or_bridge);
286
287enum drm_of_lvds_pixels {
288 DRM_OF_LVDS_EVEN = BIT(0),
289 DRM_OF_LVDS_ODD = BIT(1),
290};
291
292static int drm_of_lvds_get_port_pixels_type(struct device_node *port_node)
293{
294 bool even_pixels =
295 of_property_read_bool(port_node, "dual-lvds-even-pixels");
296 bool odd_pixels =
297 of_property_read_bool(port_node, "dual-lvds-odd-pixels");
298
299 return (even_pixels ? DRM_OF_LVDS_EVEN : 0) |
300 (odd_pixels ? DRM_OF_LVDS_ODD : 0);
301}
302
303static int drm_of_lvds_get_remote_pixels_type(
304 const struct device_node *port_node)
305{
306 struct device_node *endpoint = NULL;
307 int pixels_type = -EPIPE;
308
309 for_each_child_of_node(port_node, endpoint) {
310 struct device_node *remote_port;
311 int current_pt;
312
313 if (!of_node_name_eq(endpoint, "endpoint"))
314 continue;
315
316 remote_port = of_graph_get_remote_port(endpoint);
317 if (!remote_port) {
318 of_node_put(remote_port);
319 return -EPIPE;
320 }
321
322 current_pt = drm_of_lvds_get_port_pixels_type(remote_port);
323 of_node_put(remote_port);
324 if (pixels_type < 0)
325 pixels_type = current_pt;
326
327 /*
328 * Sanity check, ensure that all remote endpoints have the same
329 * pixel type. We may lift this restriction later if we need to
330 * support multiple sinks with different dual-link
331 * configurations by passing the endpoints explicitly to
332 * drm_of_lvds_get_dual_link_pixel_order().
333 */
334 if (!current_pt || pixels_type != current_pt)
335 return -EINVAL;
336 }
337
338 return pixels_type;
339}
340
341/**
342 * drm_of_lvds_get_dual_link_pixel_order - Get LVDS dual-link pixel order
343 * @port1: First DT port node of the Dual-link LVDS source
344 * @port2: Second DT port node of the Dual-link LVDS source
345 *
346 * An LVDS dual-link connection is made of two links, with even pixels
347 * transitting on one link, and odd pixels on the other link. This function
348 * returns, for two ports of an LVDS dual-link source, which port shall transmit
349 * the even and odd pixels, based on the requirements of the connected sink.
350 *
351 * The pixel order is determined from the dual-lvds-even-pixels and
352 * dual-lvds-odd-pixels properties in the sink's DT port nodes. If those
353 * properties are not present, or if their usage is not valid, this function
354 * returns -EINVAL.
355 *
356 * If either port is not connected, this function returns -EPIPE.
357 *
358 * @port1 and @port2 are typically DT sibling nodes, but may have different
359 * parents when, for instance, two separate LVDS encoders carry the even and odd
360 * pixels.
361 *
362 * Return:
363 * * DRM_LVDS_DUAL_LINK_EVEN_ODD_PIXELS - @port1 carries even pixels and @port2
364 * carries odd pixels
365 * * DRM_LVDS_DUAL_LINK_ODD_EVEN_PIXELS - @port1 carries odd pixels and @port2
366 * carries even pixels
367 * * -EINVAL - @port1 and @port2 are not connected to a dual-link LVDS sink, or
368 * the sink configuration is invalid
369 * * -EPIPE - when @port1 or @port2 are not connected
370 */
371int drm_of_lvds_get_dual_link_pixel_order(const struct device_node *port1,
372 const struct device_node *port2)
373{
374 int remote_p1_pt, remote_p2_pt;
375
376 if (!port1 || !port2)
377 return -EINVAL;
378
379 remote_p1_pt = drm_of_lvds_get_remote_pixels_type(port1);
380 if (remote_p1_pt < 0)
381 return remote_p1_pt;
382
383 remote_p2_pt = drm_of_lvds_get_remote_pixels_type(port2);
384 if (remote_p2_pt < 0)
385 return remote_p2_pt;
386
387 /*
388 * A valid dual-lVDS bus is found when one remote port is marked with
389 * "dual-lvds-even-pixels", and the other remote port is marked with
390 * "dual-lvds-odd-pixels", bail out if the markers are not right.
391 */
392 if (remote_p1_pt + remote_p2_pt != DRM_OF_LVDS_EVEN + DRM_OF_LVDS_ODD)
393 return -EINVAL;
394
395 return remote_p1_pt == DRM_OF_LVDS_EVEN ?
396 DRM_LVDS_DUAL_LINK_EVEN_ODD_PIXELS :
397 DRM_LVDS_DUAL_LINK_ODD_EVEN_PIXELS;
398}
399EXPORT_SYMBOL_GPL(drm_of_lvds_get_dual_link_pixel_order);
1// SPDX-License-Identifier: GPL-2.0-only
2#include <linux/component.h>
3#include <linux/export.h>
4#include <linux/list.h>
5#include <linux/media-bus-format.h>
6#include <linux/of.h>
7#include <linux/of_graph.h>
8
9#include <drm/drm_bridge.h>
10#include <drm/drm_crtc.h>
11#include <drm/drm_device.h>
12#include <drm/drm_encoder.h>
13#include <drm/drm_of.h>
14#include <drm/drm_panel.h>
15
16/**
17 * DOC: overview
18 *
19 * A set of helper functions to aid DRM drivers in parsing standard DT
20 * properties.
21 */
22
23/**
24 * drm_of_crtc_port_mask - find the mask of a registered CRTC by port OF node
25 * @dev: DRM device
26 * @port: port OF node
27 *
28 * Given a port OF node, return the possible mask of the corresponding
29 * CRTC within a device's list of CRTCs. Returns zero if not found.
30 */
31uint32_t drm_of_crtc_port_mask(struct drm_device *dev,
32 struct device_node *port)
33{
34 unsigned int index = 0;
35 struct drm_crtc *tmp;
36
37 drm_for_each_crtc(tmp, dev) {
38 if (tmp->port == port)
39 return 1 << index;
40
41 index++;
42 }
43
44 return 0;
45}
46EXPORT_SYMBOL(drm_of_crtc_port_mask);
47
48/**
49 * drm_of_find_possible_crtcs - find the possible CRTCs for an encoder port
50 * @dev: DRM device
51 * @port: encoder port to scan for endpoints
52 *
53 * Scan all endpoints attached to a port, locate their attached CRTCs,
54 * and generate the DRM mask of CRTCs which may be attached to this
55 * encoder.
56 *
57 * See Documentation/devicetree/bindings/graph.txt for the bindings.
58 */
59uint32_t drm_of_find_possible_crtcs(struct drm_device *dev,
60 struct device_node *port)
61{
62 struct device_node *remote_port, *ep;
63 uint32_t possible_crtcs = 0;
64
65 for_each_endpoint_of_node(port, ep) {
66 remote_port = of_graph_get_remote_port(ep);
67 if (!remote_port) {
68 of_node_put(ep);
69 return 0;
70 }
71
72 possible_crtcs |= drm_of_crtc_port_mask(dev, remote_port);
73
74 of_node_put(remote_port);
75 }
76
77 return possible_crtcs;
78}
79EXPORT_SYMBOL(drm_of_find_possible_crtcs);
80
81/**
82 * drm_of_component_match_add - Add a component helper OF node match rule
83 * @master: master device
84 * @matchptr: component match pointer
85 * @compare: compare function used for matching component
86 * @node: of_node
87 */
88void drm_of_component_match_add(struct device *master,
89 struct component_match **matchptr,
90 int (*compare)(struct device *, void *),
91 struct device_node *node)
92{
93 of_node_get(node);
94 component_match_add_release(master, matchptr, component_release_of,
95 compare, node);
96}
97EXPORT_SYMBOL_GPL(drm_of_component_match_add);
98
99/**
100 * drm_of_component_probe - Generic probe function for a component based master
101 * @dev: master device containing the OF node
102 * @compare_of: compare function used for matching components
103 * @m_ops: component master ops to be used
104 *
105 * Parse the platform device OF node and bind all the components associated
106 * with the master. Interface ports are added before the encoders in order to
107 * satisfy their .bind requirements
108 * See Documentation/devicetree/bindings/graph.txt for the bindings.
109 *
110 * Returns zero if successful, or one of the standard error codes if it fails.
111 */
112int drm_of_component_probe(struct device *dev,
113 int (*compare_of)(struct device *, void *),
114 const struct component_master_ops *m_ops)
115{
116 struct device_node *ep, *port, *remote;
117 struct component_match *match = NULL;
118 int i;
119
120 if (!dev->of_node)
121 return -EINVAL;
122
123 /*
124 * Bind the crtc's ports first, so that drm_of_find_possible_crtcs()
125 * called from encoder's .bind callbacks works as expected
126 */
127 for (i = 0; ; i++) {
128 port = of_parse_phandle(dev->of_node, "ports", i);
129 if (!port)
130 break;
131
132 if (of_device_is_available(port->parent))
133 drm_of_component_match_add(dev, &match, compare_of,
134 port);
135
136 of_node_put(port);
137 }
138
139 if (i == 0) {
140 dev_err(dev, "missing 'ports' property\n");
141 return -ENODEV;
142 }
143
144 if (!match) {
145 dev_err(dev, "no available port\n");
146 return -ENODEV;
147 }
148
149 /*
150 * For bound crtcs, bind the encoders attached to their remote endpoint
151 */
152 for (i = 0; ; i++) {
153 port = of_parse_phandle(dev->of_node, "ports", i);
154 if (!port)
155 break;
156
157 if (!of_device_is_available(port->parent)) {
158 of_node_put(port);
159 continue;
160 }
161
162 for_each_child_of_node(port, ep) {
163 remote = of_graph_get_remote_port_parent(ep);
164 if (!remote || !of_device_is_available(remote)) {
165 of_node_put(remote);
166 continue;
167 } else if (!of_device_is_available(remote->parent)) {
168 dev_warn(dev, "parent device of %pOF is not available\n",
169 remote);
170 of_node_put(remote);
171 continue;
172 }
173
174 drm_of_component_match_add(dev, &match, compare_of,
175 remote);
176 of_node_put(remote);
177 }
178 of_node_put(port);
179 }
180
181 return component_master_add_with_match(dev, m_ops, match);
182}
183EXPORT_SYMBOL(drm_of_component_probe);
184
185/*
186 * drm_of_encoder_active_endpoint - return the active encoder endpoint
187 * @node: device tree node containing encoder input ports
188 * @encoder: drm_encoder
189 *
190 * Given an encoder device node and a drm_encoder with a connected crtc,
191 * parse the encoder endpoint connecting to the crtc port.
192 */
193int drm_of_encoder_active_endpoint(struct device_node *node,
194 struct drm_encoder *encoder,
195 struct of_endpoint *endpoint)
196{
197 struct device_node *ep;
198 struct drm_crtc *crtc = encoder->crtc;
199 struct device_node *port;
200 int ret;
201
202 if (!node || !crtc)
203 return -EINVAL;
204
205 for_each_endpoint_of_node(node, ep) {
206 port = of_graph_get_remote_port(ep);
207 of_node_put(port);
208 if (port == crtc->port) {
209 ret = of_graph_parse_endpoint(ep, endpoint);
210 of_node_put(ep);
211 return ret;
212 }
213 }
214
215 return -EINVAL;
216}
217EXPORT_SYMBOL_GPL(drm_of_encoder_active_endpoint);
218
219/**
220 * drm_of_find_panel_or_bridge - return connected panel or bridge device
221 * @np: device tree node containing encoder output ports
222 * @port: port in the device tree node
223 * @endpoint: endpoint in the device tree node
224 * @panel: pointer to hold returned drm_panel
225 * @bridge: pointer to hold returned drm_bridge
226 *
227 * Given a DT node's port and endpoint number, find the connected node and
228 * return either the associated struct drm_panel or drm_bridge device. Either
229 * @panel or @bridge must not be NULL.
230 *
231 * This function is deprecated and should not be used in new drivers. Use
232 * devm_drm_of_get_bridge() instead.
233 *
234 * Returns zero if successful, or one of the standard error codes if it fails.
235 */
236int drm_of_find_panel_or_bridge(const struct device_node *np,
237 int port, int endpoint,
238 struct drm_panel **panel,
239 struct drm_bridge **bridge)
240{
241 int ret = -EPROBE_DEFER;
242 struct device_node *remote;
243
244 if (!panel && !bridge)
245 return -EINVAL;
246 if (panel)
247 *panel = NULL;
248
249 /*
250 * of_graph_get_remote_node() produces a noisy error message if port
251 * node isn't found and the absence of the port is a legit case here,
252 * so at first we silently check whether graph presents in the
253 * device-tree node.
254 */
255 if (!of_graph_is_present(np))
256 return -ENODEV;
257
258 remote = of_graph_get_remote_node(np, port, endpoint);
259 if (!remote)
260 return -ENODEV;
261
262 if (panel) {
263 *panel = of_drm_find_panel(remote);
264 if (!IS_ERR(*panel))
265 ret = 0;
266 else
267 *panel = NULL;
268 }
269
270 /* No panel found yet, check for a bridge next. */
271 if (bridge) {
272 if (ret) {
273 *bridge = of_drm_find_bridge(remote);
274 if (*bridge)
275 ret = 0;
276 } else {
277 *bridge = NULL;
278 }
279
280 }
281
282 of_node_put(remote);
283 return ret;
284}
285EXPORT_SYMBOL_GPL(drm_of_find_panel_or_bridge);
286
287enum drm_of_lvds_pixels {
288 DRM_OF_LVDS_EVEN = BIT(0),
289 DRM_OF_LVDS_ODD = BIT(1),
290};
291
292static int drm_of_lvds_get_port_pixels_type(struct device_node *port_node)
293{
294 bool even_pixels =
295 of_property_read_bool(port_node, "dual-lvds-even-pixels");
296 bool odd_pixels =
297 of_property_read_bool(port_node, "dual-lvds-odd-pixels");
298
299 return (even_pixels ? DRM_OF_LVDS_EVEN : 0) |
300 (odd_pixels ? DRM_OF_LVDS_ODD : 0);
301}
302
303static int drm_of_lvds_get_remote_pixels_type(
304 const struct device_node *port_node)
305{
306 struct device_node *endpoint = NULL;
307 int pixels_type = -EPIPE;
308
309 for_each_child_of_node(port_node, endpoint) {
310 struct device_node *remote_port;
311 int current_pt;
312
313 if (!of_node_name_eq(endpoint, "endpoint"))
314 continue;
315
316 remote_port = of_graph_get_remote_port(endpoint);
317 if (!remote_port) {
318 of_node_put(endpoint);
319 return -EPIPE;
320 }
321
322 current_pt = drm_of_lvds_get_port_pixels_type(remote_port);
323 of_node_put(remote_port);
324 if (pixels_type < 0)
325 pixels_type = current_pt;
326
327 /*
328 * Sanity check, ensure that all remote endpoints have the same
329 * pixel type. We may lift this restriction later if we need to
330 * support multiple sinks with different dual-link
331 * configurations by passing the endpoints explicitly to
332 * drm_of_lvds_get_dual_link_pixel_order().
333 */
334 if (!current_pt || pixels_type != current_pt) {
335 of_node_put(endpoint);
336 return -EINVAL;
337 }
338 }
339
340 return pixels_type;
341}
342
343/**
344 * drm_of_lvds_get_dual_link_pixel_order - Get LVDS dual-link pixel order
345 * @port1: First DT port node of the Dual-link LVDS source
346 * @port2: Second DT port node of the Dual-link LVDS source
347 *
348 * An LVDS dual-link connection is made of two links, with even pixels
349 * transitting on one link, and odd pixels on the other link. This function
350 * returns, for two ports of an LVDS dual-link source, which port shall transmit
351 * the even and odd pixels, based on the requirements of the connected sink.
352 *
353 * The pixel order is determined from the dual-lvds-even-pixels and
354 * dual-lvds-odd-pixels properties in the sink's DT port nodes. If those
355 * properties are not present, or if their usage is not valid, this function
356 * returns -EINVAL.
357 *
358 * If either port is not connected, this function returns -EPIPE.
359 *
360 * @port1 and @port2 are typically DT sibling nodes, but may have different
361 * parents when, for instance, two separate LVDS encoders carry the even and odd
362 * pixels.
363 *
364 * Return:
365 * * DRM_LVDS_DUAL_LINK_EVEN_ODD_PIXELS - @port1 carries even pixels and @port2
366 * carries odd pixels
367 * * DRM_LVDS_DUAL_LINK_ODD_EVEN_PIXELS - @port1 carries odd pixels and @port2
368 * carries even pixels
369 * * -EINVAL - @port1 and @port2 are not connected to a dual-link LVDS sink, or
370 * the sink configuration is invalid
371 * * -EPIPE - when @port1 or @port2 are not connected
372 */
373int drm_of_lvds_get_dual_link_pixel_order(const struct device_node *port1,
374 const struct device_node *port2)
375{
376 int remote_p1_pt, remote_p2_pt;
377
378 if (!port1 || !port2)
379 return -EINVAL;
380
381 remote_p1_pt = drm_of_lvds_get_remote_pixels_type(port1);
382 if (remote_p1_pt < 0)
383 return remote_p1_pt;
384
385 remote_p2_pt = drm_of_lvds_get_remote_pixels_type(port2);
386 if (remote_p2_pt < 0)
387 return remote_p2_pt;
388
389 /*
390 * A valid dual-lVDS bus is found when one remote port is marked with
391 * "dual-lvds-even-pixels", and the other remote port is marked with
392 * "dual-lvds-odd-pixels", bail out if the markers are not right.
393 */
394 if (remote_p1_pt + remote_p2_pt != DRM_OF_LVDS_EVEN + DRM_OF_LVDS_ODD)
395 return -EINVAL;
396
397 return remote_p1_pt == DRM_OF_LVDS_EVEN ?
398 DRM_LVDS_DUAL_LINK_EVEN_ODD_PIXELS :
399 DRM_LVDS_DUAL_LINK_ODD_EVEN_PIXELS;
400}
401EXPORT_SYMBOL_GPL(drm_of_lvds_get_dual_link_pixel_order);
402
403/**
404 * drm_of_lvds_get_data_mapping - Get LVDS data mapping
405 * @port: DT port node of the LVDS source or sink
406 *
407 * Convert DT "data-mapping" property string value into media bus format value.
408 *
409 * Return:
410 * * MEDIA_BUS_FMT_RGB666_1X7X3_SPWG - data-mapping is "jeida-18"
411 * * MEDIA_BUS_FMT_RGB888_1X7X4_JEIDA - data-mapping is "jeida-24"
412 * * MEDIA_BUS_FMT_RGB888_1X7X4_SPWG - data-mapping is "vesa-24"
413 * * -EINVAL - the "data-mapping" property is unsupported
414 * * -ENODEV - the "data-mapping" property is missing
415 */
416int drm_of_lvds_get_data_mapping(const struct device_node *port)
417{
418 const char *mapping;
419 int ret;
420
421 ret = of_property_read_string(port, "data-mapping", &mapping);
422 if (ret < 0)
423 return -ENODEV;
424
425 if (!strcmp(mapping, "jeida-18"))
426 return MEDIA_BUS_FMT_RGB666_1X7X3_SPWG;
427 if (!strcmp(mapping, "jeida-24"))
428 return MEDIA_BUS_FMT_RGB888_1X7X4_JEIDA;
429 if (!strcmp(mapping, "vesa-24"))
430 return MEDIA_BUS_FMT_RGB888_1X7X4_SPWG;
431
432 return -EINVAL;
433}
434EXPORT_SYMBOL_GPL(drm_of_lvds_get_data_mapping);
435
436/**
437 * drm_of_get_data_lanes_count - Get DSI/(e)DP data lane count
438 * @endpoint: DT endpoint node of the DSI/(e)DP source or sink
439 * @min: minimum supported number of data lanes
440 * @max: maximum supported number of data lanes
441 *
442 * Count DT "data-lanes" property elements and check for validity.
443 *
444 * Return:
445 * * min..max - positive integer count of "data-lanes" elements
446 * * -ve - the "data-lanes" property is missing or invalid
447 * * -EINVAL - the "data-lanes" property is unsupported
448 */
449int drm_of_get_data_lanes_count(const struct device_node *endpoint,
450 const unsigned int min, const unsigned int max)
451{
452 int ret;
453
454 ret = of_property_count_u32_elems(endpoint, "data-lanes");
455 if (ret < 0)
456 return ret;
457
458 if (ret < min || ret > max)
459 return -EINVAL;
460
461 return ret;
462}
463EXPORT_SYMBOL_GPL(drm_of_get_data_lanes_count);
464
465/**
466 * drm_of_get_data_lanes_count_ep - Get DSI/(e)DP data lane count by endpoint
467 * @port: DT port node of the DSI/(e)DP source or sink
468 * @port_reg: identifier (value of reg property) of the parent port node
469 * @reg: identifier (value of reg property) of the endpoint node
470 * @min: minimum supported number of data lanes
471 * @max: maximum supported number of data lanes
472 *
473 * Count DT "data-lanes" property elements and check for validity.
474 * This variant uses endpoint specifier.
475 *
476 * Return:
477 * * min..max - positive integer count of "data-lanes" elements
478 * * -EINVAL - the "data-mapping" property is unsupported
479 * * -ENODEV - the "data-mapping" property is missing
480 */
481int drm_of_get_data_lanes_count_ep(const struct device_node *port,
482 int port_reg, int reg,
483 const unsigned int min,
484 const unsigned int max)
485{
486 struct device_node *endpoint;
487 int ret;
488
489 endpoint = of_graph_get_endpoint_by_regs(port, port_reg, reg);
490 ret = drm_of_get_data_lanes_count(endpoint, min, max);
491 of_node_put(endpoint);
492
493 return ret;
494}
495EXPORT_SYMBOL_GPL(drm_of_get_data_lanes_count_ep);