2 * V4L2 fwnode binding parsing library
4 * The origins of the V4L2 fwnode library are in V4L2 OF library that
5 * formerly was located in v4l2-of.c.
7 * Copyright (c) 2016 Intel Corporation.
10 * Copyright (C) 2012 - 2013 Samsung Electronics Co., Ltd.
13 * Copyright (C) 2012 Renesas Electronics Corp.
16 * This program is free software; you can redistribute it and/or modify
17 * it under the terms of version 2 of the GNU General Public License as
18 * published by the Free Software Foundation.
20 #include <linux/acpi.h>
21 #include <linux/kernel.h>
23 #include <linux/module.h>
25 #include <linux/property.h>
26 #include <linux/slab.h>
27 #include <linux/string.h>
28 #include <linux/types.h>
30 #include <media/v4l2-async.h>
31 #include <media/v4l2-fwnode.h>
32 #include <media/v4l2-subdev.h>
34 enum v4l2_fwnode_bus_type {
35 V4L2_FWNODE_BUS_TYPE_GUESS = 0,
36 V4L2_FWNODE_BUS_TYPE_CSI2_CPHY,
37 V4L2_FWNODE_BUS_TYPE_CSI1,
38 V4L2_FWNODE_BUS_TYPE_CCP2,
39 V4L2_FWNODE_BUS_TYPE_CSI2_DPHY,
40 V4L2_FWNODE_BUS_TYPE_PARALLEL,
41 V4L2_FWNODE_BUS_TYPE_BT656,
42 NR_OF_V4L2_FWNODE_BUS_TYPE,
45 static const struct v4l2_fwnode_bus_conv {
46 enum v4l2_fwnode_bus_type fwnode_bus_type;
47 enum v4l2_mbus_type mbus_type;
51 V4L2_FWNODE_BUS_TYPE_GUESS,
55 V4L2_FWNODE_BUS_TYPE_CSI2_CPHY,
59 V4L2_FWNODE_BUS_TYPE_CSI1,
63 V4L2_FWNODE_BUS_TYPE_CCP2,
65 "compact camera port 2",
67 V4L2_FWNODE_BUS_TYPE_CSI2_DPHY,
71 V4L2_FWNODE_BUS_TYPE_PARALLEL,
75 V4L2_FWNODE_BUS_TYPE_BT656,
81 static const struct v4l2_fwnode_bus_conv *
82 get_v4l2_fwnode_bus_conv_by_fwnode_bus(enum v4l2_fwnode_bus_type type)
86 for (i = 0; i < ARRAY_SIZE(buses); i++)
87 if (buses[i].fwnode_bus_type == type)
93 static enum v4l2_mbus_type
94 v4l2_fwnode_bus_type_to_mbus(enum v4l2_fwnode_bus_type type)
96 const struct v4l2_fwnode_bus_conv *conv =
97 get_v4l2_fwnode_bus_conv_by_fwnode_bus(type);
99 return conv ? conv->mbus_type : V4L2_MBUS_UNKNOWN;
103 v4l2_fwnode_bus_type_to_string(enum v4l2_fwnode_bus_type type)
105 const struct v4l2_fwnode_bus_conv *conv =
106 get_v4l2_fwnode_bus_conv_by_fwnode_bus(type);
108 return conv ? conv->name : "not found";
111 static const struct v4l2_fwnode_bus_conv *
112 get_v4l2_fwnode_bus_conv_by_mbus(enum v4l2_mbus_type type)
116 for (i = 0; i < ARRAY_SIZE(buses); i++)
117 if (buses[i].mbus_type == type)
124 v4l2_fwnode_mbus_type_to_string(enum v4l2_mbus_type type)
126 const struct v4l2_fwnode_bus_conv *conv =
127 get_v4l2_fwnode_bus_conv_by_mbus(type);
129 return conv ? conv->name : "not found";
132 static int v4l2_fwnode_endpoint_parse_csi2_bus(struct fwnode_handle *fwnode,
133 struct v4l2_fwnode_endpoint *vep,
134 enum v4l2_mbus_type bus_type)
136 struct v4l2_fwnode_bus_mipi_csi2 *bus = &vep->bus.mipi_csi2;
137 bool have_clk_lane = false, have_data_lanes = false,
138 have_lane_polarities = false;
139 unsigned int flags = 0, lanes_used = 0;
140 u32 array[1 + V4L2_FWNODE_CSI2_MAX_DATA_LANES];
142 unsigned int num_data_lanes = 0;
143 bool use_default_lane_mapping = false;
148 if (bus_type == V4L2_MBUS_CSI2_DPHY ||
149 bus_type == V4L2_MBUS_CSI2_CPHY) {
150 use_default_lane_mapping = true;
152 num_data_lanes = min_t(u32, bus->num_data_lanes,
153 V4L2_FWNODE_CSI2_MAX_DATA_LANES);
155 clock_lane = bus->clock_lane;
157 use_default_lane_mapping = false;
159 for (i = 0; i < num_data_lanes; i++) {
160 array[i] = bus->data_lanes[i];
162 use_default_lane_mapping = false;
165 if (use_default_lane_mapping)
166 pr_debug("using default lane mapping\n");
169 rval = fwnode_property_read_u32_array(fwnode, "data-lanes", NULL, 0);
172 min_t(int, V4L2_FWNODE_CSI2_MAX_DATA_LANES, rval);
174 fwnode_property_read_u32_array(fwnode, "data-lanes", array,
177 have_data_lanes = true;
180 for (i = 0; i < num_data_lanes; i++) {
181 if (lanes_used & BIT(array[i])) {
182 if (have_data_lanes || !use_default_lane_mapping)
183 pr_warn("duplicated lane %u in data-lanes, using defaults\n",
185 use_default_lane_mapping = true;
187 lanes_used |= BIT(array[i]);
190 pr_debug("lane %u position %u\n", i, array[i]);
193 rval = fwnode_property_read_u32_array(fwnode, "lane-polarities", NULL,
196 if (rval != 1 + num_data_lanes /* clock+data */) {
197 pr_warn("invalid number of lane-polarities entries (need %u, got %u)\n",
198 1 + num_data_lanes, rval);
202 have_lane_polarities = true;
205 if (!fwnode_property_read_u32(fwnode, "clock-lanes", &v)) {
207 pr_debug("clock lane position %u\n", v);
208 have_clk_lane = true;
211 if (lanes_used & BIT(clock_lane)) {
212 if (have_clk_lane || !use_default_lane_mapping)
213 pr_warn("duplicated lane %u in clock-lanes, using defaults\n",
215 use_default_lane_mapping = true;
218 if (fwnode_property_present(fwnode, "clock-noncontinuous")) {
219 flags |= V4L2_MBUS_CSI2_NONCONTINUOUS_CLOCK;
220 pr_debug("non-continuous clock\n");
222 flags |= V4L2_MBUS_CSI2_CONTINUOUS_CLOCK;
225 if (bus_type == V4L2_MBUS_CSI2_DPHY ||
226 bus_type == V4L2_MBUS_CSI2_CPHY || lanes_used ||
227 have_clk_lane || (flags & ~V4L2_MBUS_CSI2_CONTINUOUS_CLOCK)) {
229 if (bus_type == V4L2_MBUS_UNKNOWN)
230 vep->bus_type = V4L2_MBUS_CSI2_DPHY;
231 bus->num_data_lanes = num_data_lanes;
233 if (use_default_lane_mapping) {
235 for (i = 0; i < num_data_lanes; i++)
236 bus->data_lanes[i] = 1 + i;
238 bus->clock_lane = clock_lane;
239 for (i = 0; i < num_data_lanes; i++)
240 bus->data_lanes[i] = array[i];
243 if (have_lane_polarities) {
244 fwnode_property_read_u32_array(fwnode,
245 "lane-polarities", array,
248 for (i = 0; i < 1 + num_data_lanes; i++) {
249 bus->lane_polarities[i] = array[i];
250 pr_debug("lane %u polarity %sinverted",
251 i, array[i] ? "" : "not ");
254 pr_debug("no lane polarities defined, assuming not inverted\n");
261 #define PARALLEL_MBUS_FLAGS (V4L2_MBUS_HSYNC_ACTIVE_HIGH | \
262 V4L2_MBUS_HSYNC_ACTIVE_LOW | \
263 V4L2_MBUS_VSYNC_ACTIVE_HIGH | \
264 V4L2_MBUS_VSYNC_ACTIVE_LOW | \
265 V4L2_MBUS_FIELD_EVEN_HIGH | \
266 V4L2_MBUS_FIELD_EVEN_LOW)
269 v4l2_fwnode_endpoint_parse_parallel_bus(struct fwnode_handle *fwnode,
270 struct v4l2_fwnode_endpoint *vep,
271 enum v4l2_mbus_type bus_type)
273 struct v4l2_fwnode_bus_parallel *bus = &vep->bus.parallel;
274 unsigned int flags = 0;
277 if (bus_type == V4L2_MBUS_PARALLEL || bus_type == V4L2_MBUS_BT656)
280 if (!fwnode_property_read_u32(fwnode, "hsync-active", &v)) {
281 flags &= ~(V4L2_MBUS_HSYNC_ACTIVE_HIGH |
282 V4L2_MBUS_HSYNC_ACTIVE_LOW);
283 flags |= v ? V4L2_MBUS_HSYNC_ACTIVE_HIGH :
284 V4L2_MBUS_HSYNC_ACTIVE_LOW;
285 pr_debug("hsync-active %s\n", v ? "high" : "low");
288 if (!fwnode_property_read_u32(fwnode, "vsync-active", &v)) {
289 flags &= ~(V4L2_MBUS_VSYNC_ACTIVE_HIGH |
290 V4L2_MBUS_VSYNC_ACTIVE_LOW);
291 flags |= v ? V4L2_MBUS_VSYNC_ACTIVE_HIGH :
292 V4L2_MBUS_VSYNC_ACTIVE_LOW;
293 pr_debug("vsync-active %s\n", v ? "high" : "low");
296 if (!fwnode_property_read_u32(fwnode, "field-even-active", &v)) {
297 flags &= ~(V4L2_MBUS_FIELD_EVEN_HIGH |
298 V4L2_MBUS_FIELD_EVEN_LOW);
299 flags |= v ? V4L2_MBUS_FIELD_EVEN_HIGH :
300 V4L2_MBUS_FIELD_EVEN_LOW;
301 pr_debug("field-even-active %s\n", v ? "high" : "low");
304 if (!fwnode_property_read_u32(fwnode, "pclk-sample", &v)) {
305 flags &= ~(V4L2_MBUS_PCLK_SAMPLE_RISING |
306 V4L2_MBUS_PCLK_SAMPLE_FALLING);
307 flags |= v ? V4L2_MBUS_PCLK_SAMPLE_RISING :
308 V4L2_MBUS_PCLK_SAMPLE_FALLING;
309 pr_debug("pclk-sample %s\n", v ? "high" : "low");
312 if (!fwnode_property_read_u32(fwnode, "data-active", &v)) {
313 flags &= ~(V4L2_MBUS_DATA_ACTIVE_HIGH |
314 V4L2_MBUS_DATA_ACTIVE_LOW);
315 flags |= v ? V4L2_MBUS_DATA_ACTIVE_HIGH :
316 V4L2_MBUS_DATA_ACTIVE_LOW;
317 pr_debug("data-active %s\n", v ? "high" : "low");
320 if (fwnode_property_present(fwnode, "slave-mode")) {
321 pr_debug("slave mode\n");
322 flags &= ~V4L2_MBUS_MASTER;
323 flags |= V4L2_MBUS_SLAVE;
325 flags &= ~V4L2_MBUS_SLAVE;
326 flags |= V4L2_MBUS_MASTER;
329 if (!fwnode_property_read_u32(fwnode, "bus-width", &v)) {
331 pr_debug("bus-width %u\n", v);
334 if (!fwnode_property_read_u32(fwnode, "data-shift", &v)) {
336 pr_debug("data-shift %u\n", v);
339 if (!fwnode_property_read_u32(fwnode, "sync-on-green-active", &v)) {
340 flags &= ~(V4L2_MBUS_VIDEO_SOG_ACTIVE_HIGH |
341 V4L2_MBUS_VIDEO_SOG_ACTIVE_LOW);
342 flags |= v ? V4L2_MBUS_VIDEO_SOG_ACTIVE_HIGH :
343 V4L2_MBUS_VIDEO_SOG_ACTIVE_LOW;
344 pr_debug("sync-on-green-active %s\n", v ? "high" : "low");
347 if (!fwnode_property_read_u32(fwnode, "data-enable-active", &v)) {
348 flags &= ~(V4L2_MBUS_DATA_ENABLE_HIGH |
349 V4L2_MBUS_DATA_ENABLE_LOW);
350 flags |= v ? V4L2_MBUS_DATA_ENABLE_HIGH :
351 V4L2_MBUS_DATA_ENABLE_LOW;
352 pr_debug("data-enable-active %s\n", v ? "high" : "low");
358 if (flags & PARALLEL_MBUS_FLAGS)
359 vep->bus_type = V4L2_MBUS_PARALLEL;
361 vep->bus_type = V4L2_MBUS_BT656;
363 case V4L2_MBUS_PARALLEL:
364 vep->bus_type = V4L2_MBUS_PARALLEL;
367 case V4L2_MBUS_BT656:
368 vep->bus_type = V4L2_MBUS_BT656;
369 bus->flags = flags & ~PARALLEL_MBUS_FLAGS;
375 v4l2_fwnode_endpoint_parse_csi1_bus(struct fwnode_handle *fwnode,
376 struct v4l2_fwnode_endpoint *vep,
377 enum v4l2_mbus_type bus_type)
379 struct v4l2_fwnode_bus_mipi_csi1 *bus = &vep->bus.mipi_csi1;
382 if (!fwnode_property_read_u32(fwnode, "clock-inv", &v)) {
384 pr_debug("clock-inv %u\n", v);
387 if (!fwnode_property_read_u32(fwnode, "strobe", &v)) {
389 pr_debug("strobe %u\n", v);
392 if (!fwnode_property_read_u32(fwnode, "data-lanes", &v)) {
394 pr_debug("data-lanes %u\n", v);
397 if (!fwnode_property_read_u32(fwnode, "clock-lanes", &v)) {
399 pr_debug("clock-lanes %u\n", v);
402 if (bus_type == V4L2_MBUS_CCP2)
403 vep->bus_type = V4L2_MBUS_CCP2;
405 vep->bus_type = V4L2_MBUS_CSI1;
408 static int __v4l2_fwnode_endpoint_parse(struct fwnode_handle *fwnode,
409 struct v4l2_fwnode_endpoint *vep)
411 u32 bus_type = V4L2_FWNODE_BUS_TYPE_GUESS;
412 enum v4l2_mbus_type mbus_type;
415 if (vep->bus_type == V4L2_MBUS_UNKNOWN) {
416 /* Zero fields from bus union to until the end */
418 sizeof(*vep) - offsetof(typeof(*vep), bus));
421 pr_debug("===== begin V4L2 endpoint properties\n");
424 * Zero the fwnode graph endpoint memory in case we don't end up parsing
427 memset(&vep->base, 0, sizeof(vep->base));
429 fwnode_property_read_u32(fwnode, "bus-type", &bus_type);
430 pr_debug("fwnode video bus type %s (%u), mbus type %s (%u)\n",
431 v4l2_fwnode_bus_type_to_string(bus_type), bus_type,
432 v4l2_fwnode_mbus_type_to_string(vep->bus_type),
434 mbus_type = v4l2_fwnode_bus_type_to_mbus(bus_type);
436 if (vep->bus_type != V4L2_MBUS_UNKNOWN) {
437 if (mbus_type != V4L2_MBUS_UNKNOWN &&
438 vep->bus_type != mbus_type) {
439 pr_debug("expecting bus type %s\n",
440 v4l2_fwnode_mbus_type_to_string(vep->bus_type));
444 vep->bus_type = mbus_type;
447 switch (vep->bus_type) {
448 case V4L2_MBUS_UNKNOWN:
449 rval = v4l2_fwnode_endpoint_parse_csi2_bus(fwnode, vep,
454 if (vep->bus_type == V4L2_MBUS_UNKNOWN)
455 v4l2_fwnode_endpoint_parse_parallel_bus(fwnode, vep,
458 pr_debug("assuming media bus type %s (%u)\n",
459 v4l2_fwnode_mbus_type_to_string(vep->bus_type),
465 v4l2_fwnode_endpoint_parse_csi1_bus(fwnode, vep, vep->bus_type);
468 case V4L2_MBUS_CSI2_DPHY:
469 case V4L2_MBUS_CSI2_CPHY:
470 rval = v4l2_fwnode_endpoint_parse_csi2_bus(fwnode, vep,
476 case V4L2_MBUS_PARALLEL:
477 case V4L2_MBUS_BT656:
478 v4l2_fwnode_endpoint_parse_parallel_bus(fwnode, vep,
483 pr_warn("unsupported bus type %u\n", mbus_type);
487 fwnode_graph_parse_endpoint(fwnode, &vep->base);
492 int v4l2_fwnode_endpoint_parse(struct fwnode_handle *fwnode,
493 struct v4l2_fwnode_endpoint *vep)
497 ret = __v4l2_fwnode_endpoint_parse(fwnode, vep);
499 pr_debug("===== end V4L2 endpoint properties\n");
503 EXPORT_SYMBOL_GPL(v4l2_fwnode_endpoint_parse);
505 void v4l2_fwnode_endpoint_free(struct v4l2_fwnode_endpoint *vep)
507 if (IS_ERR_OR_NULL(vep))
510 kfree(vep->link_frequencies);
512 EXPORT_SYMBOL_GPL(v4l2_fwnode_endpoint_free);
514 int v4l2_fwnode_endpoint_alloc_parse(struct fwnode_handle *fwnode,
515 struct v4l2_fwnode_endpoint *vep)
519 rval = __v4l2_fwnode_endpoint_parse(fwnode, vep);
523 rval = fwnode_property_read_u64_array(fwnode, "link-frequencies",
528 vep->link_frequencies =
529 kmalloc_array(rval, sizeof(*vep->link_frequencies),
531 if (!vep->link_frequencies)
534 vep->nr_of_link_frequencies = rval;
536 rval = fwnode_property_read_u64_array(fwnode,
538 vep->link_frequencies,
539 vep->nr_of_link_frequencies);
541 v4l2_fwnode_endpoint_free(vep);
545 for (i = 0; i < vep->nr_of_link_frequencies; i++)
546 pr_info("link-frequencies %u value %llu\n", i,
547 vep->link_frequencies[i]);
550 pr_debug("===== end V4L2 endpoint properties\n");
554 EXPORT_SYMBOL_GPL(v4l2_fwnode_endpoint_alloc_parse);
556 int v4l2_fwnode_parse_link(struct fwnode_handle *__fwnode,
557 struct v4l2_fwnode_link *link)
559 const char *port_prop = is_of_node(__fwnode) ? "reg" : "port";
560 struct fwnode_handle *fwnode;
562 memset(link, 0, sizeof(*link));
564 fwnode = fwnode_get_parent(__fwnode);
565 fwnode_property_read_u32(fwnode, port_prop, &link->local_port);
566 fwnode = fwnode_get_next_parent(fwnode);
567 if (is_of_node(fwnode) && of_node_name_eq(to_of_node(fwnode), "ports"))
568 fwnode = fwnode_get_next_parent(fwnode);
569 link->local_node = fwnode;
571 fwnode = fwnode_graph_get_remote_endpoint(__fwnode);
573 fwnode_handle_put(fwnode);
577 fwnode = fwnode_get_parent(fwnode);
578 fwnode_property_read_u32(fwnode, port_prop, &link->remote_port);
579 fwnode = fwnode_get_next_parent(fwnode);
580 if (is_of_node(fwnode) && of_node_name_eq(to_of_node(fwnode), "ports"))
581 fwnode = fwnode_get_next_parent(fwnode);
582 link->remote_node = fwnode;
586 EXPORT_SYMBOL_GPL(v4l2_fwnode_parse_link);
588 void v4l2_fwnode_put_link(struct v4l2_fwnode_link *link)
590 fwnode_handle_put(link->local_node);
591 fwnode_handle_put(link->remote_node);
593 EXPORT_SYMBOL_GPL(v4l2_fwnode_put_link);
596 v4l2_async_notifier_fwnode_parse_endpoint(struct device *dev,
597 struct v4l2_async_notifier *notifier,
598 struct fwnode_handle *endpoint,
599 unsigned int asd_struct_size,
600 parse_endpoint_func parse_endpoint)
602 struct v4l2_fwnode_endpoint vep = { .bus_type = 0 };
603 struct v4l2_async_subdev *asd;
606 asd = kzalloc(asd_struct_size, GFP_KERNEL);
610 asd->match_type = V4L2_ASYNC_MATCH_FWNODE;
612 fwnode_graph_get_remote_port_parent(endpoint);
613 if (!asd->match.fwnode) {
614 dev_dbg(dev, "no remote endpoint found\n");
619 ret = v4l2_fwnode_endpoint_alloc_parse(endpoint, &vep);
621 dev_warn(dev, "unable to parse V4L2 fwnode endpoint (%d)\n",
626 ret = parse_endpoint ? parse_endpoint(dev, &vep, asd) : 0;
627 if (ret == -ENOTCONN)
628 dev_dbg(dev, "ignoring port@%u/endpoint@%u\n", vep.base.port,
632 "driver could not parse port@%u/endpoint@%u (%d)\n",
633 vep.base.port, vep.base.id, ret);
634 v4l2_fwnode_endpoint_free(&vep);
638 ret = v4l2_async_notifier_add_subdev(notifier, asd);
640 /* not an error if asd already exists */
649 fwnode_handle_put(asd->match.fwnode);
652 return ret == -ENOTCONN ? 0 : ret;
656 __v4l2_async_notifier_parse_fwnode_ep(struct device *dev,
657 struct v4l2_async_notifier *notifier,
658 size_t asd_struct_size,
661 parse_endpoint_func parse_endpoint)
663 struct fwnode_handle *fwnode;
666 if (WARN_ON(asd_struct_size < sizeof(struct v4l2_async_subdev)))
669 fwnode_graph_for_each_endpoint(dev_fwnode(dev), fwnode) {
670 struct fwnode_handle *dev_fwnode;
673 dev_fwnode = fwnode_graph_get_port_parent(fwnode);
674 is_available = fwnode_device_is_available(dev_fwnode);
675 fwnode_handle_put(dev_fwnode);
680 struct fwnode_endpoint ep;
682 ret = fwnode_graph_parse_endpoint(fwnode, &ep);
690 ret = v4l2_async_notifier_fwnode_parse_endpoint(dev,
699 fwnode_handle_put(fwnode);
705 v4l2_async_notifier_parse_fwnode_endpoints(struct device *dev,
706 struct v4l2_async_notifier *notifier,
707 size_t asd_struct_size,
708 parse_endpoint_func parse_endpoint)
710 return __v4l2_async_notifier_parse_fwnode_ep(dev, notifier,
712 false, parse_endpoint);
714 EXPORT_SYMBOL_GPL(v4l2_async_notifier_parse_fwnode_endpoints);
717 v4l2_async_notifier_parse_fwnode_endpoints_by_port(struct device *dev,
718 struct v4l2_async_notifier *notifier,
719 size_t asd_struct_size,
721 parse_endpoint_func parse_endpoint)
723 return __v4l2_async_notifier_parse_fwnode_ep(dev, notifier,
728 EXPORT_SYMBOL_GPL(v4l2_async_notifier_parse_fwnode_endpoints_by_port);
731 * v4l2_fwnode_reference_parse - parse references for async sub-devices
732 * @dev: the device node the properties of which are parsed for references
733 * @notifier: the async notifier where the async subdevs will be added
734 * @prop: the name of the property
736 * Return: 0 on success
737 * -ENOENT if no entries were found
738 * -ENOMEM if memory allocation failed
739 * -EINVAL if property parsing failed
741 static int v4l2_fwnode_reference_parse(struct device *dev,
742 struct v4l2_async_notifier *notifier,
745 struct fwnode_reference_args args;
750 !(ret = fwnode_property_get_reference_args(dev_fwnode(dev),
754 fwnode_handle_put(args.fwnode);
760 * Note that right now both -ENODATA and -ENOENT may signal
761 * out-of-bounds access. Return the error in cases other than that.
763 if (ret != -ENOENT && ret != -ENODATA)
767 !fwnode_property_get_reference_args(dev_fwnode(dev), prop, NULL,
770 struct v4l2_async_subdev *asd;
772 asd = v4l2_async_notifier_add_fwnode_subdev(notifier,
777 /* not an error if asd already exists */
778 if (ret == -EEXIST) {
779 fwnode_handle_put(args.fwnode);
790 fwnode_handle_put(args.fwnode);
795 * v4l2_fwnode_reference_get_int_prop - parse a reference with integer
797 * @fwnode: fwnode to read @prop from
798 * @notifier: notifier for @dev
799 * @prop: the name of the property
800 * @index: the index of the reference to get
801 * @props: the array of integer property names
802 * @nprops: the number of integer property names in @nprops
804 * First find an fwnode referred to by the reference at @index in @prop.
806 * Then under that fwnode, @nprops times, for each property in @props,
807 * iteratively follow child nodes starting from fwnode such that they have the
808 * property in @props array at the index of the child node distance from the
809 * root node and the value of that property matching with the integer argument
810 * of the reference, at the same index.
812 * The child fwnode reached at the end of the iteration is then returned to the
815 * The core reason for this is that you cannot refer to just any node in ACPI.
816 * So to refer to an endpoint (easy in DT) you need to refer to a device, then
817 * provide a list of (property name, property value) tuples where each tuple
818 * uniquely identifies a child node. The first tuple identifies a child directly
819 * underneath the device fwnode, the next tuple identifies a child node
820 * underneath the fwnode identified by the previous tuple, etc. until you
821 * reached the fwnode you need.
823 * An example with a graph, as defined in Documentation/acpi/dsd/graph.txt:
825 * Scope (\_SB.PCI0.I2C2)
829 * Name (_DSD, Package () {
830 * ToUUID("daffd814-6eba-4d8c-8a91-bc9bbf4aa301"),
834 * Package () { "nokia,smia" }
837 * ToUUID("dbb8e3e6-5886-4ba6-8795-1319f52a966b"),
839 * Package () { "port0", "PRT0" },
842 * Name (PRT0, Package() {
843 * ToUUID("daffd814-6eba-4d8c-8a91-bc9bbf4aa301"),
845 * Package () { "port", 0 },
847 * ToUUID("dbb8e3e6-5886-4ba6-8795-1319f52a966b"),
849 * Package () { "endpoint0", "EP00" },
852 * Name (EP00, Package() {
853 * ToUUID("daffd814-6eba-4d8c-8a91-bc9bbf4aa301"),
855 * Package () { "endpoint", 0 },
859 * \_SB.PCI0.ISP, 4, 0
871 * Name (_DSD, Package () {
872 * ToUUID("dbb8e3e6-5886-4ba6-8795-1319f52a966b"),
874 * Package () { "port4", "PRT4" },
878 * Name (PRT4, Package() {
879 * ToUUID("daffd814-6eba-4d8c-8a91-bc9bbf4aa301"),
881 * Package () { "port", 4 },
883 * ToUUID("dbb8e3e6-5886-4ba6-8795-1319f52a966b"),
885 * Package () { "endpoint0", "EP40" },
889 * Name (EP40, Package() {
890 * ToUUID("daffd814-6eba-4d8c-8a91-bc9bbf4aa301"),
892 * Package () { "endpoint", 0 },
896 * \_SB.PCI0.I2C2.CAM0,
905 * From the EP40 node under ISP device, you could parse the graph remote
906 * endpoint using v4l2_fwnode_reference_get_int_prop with these arguments:
908 * @fwnode: fwnode referring to EP40 under ISP.
909 * @prop: "remote-endpoint"
911 * @props: "port", "endpoint"
914 * And you'd get back fwnode referring to EP00 under CAM0.
916 * The same works the other way around: if you use EP00 under CAM0 as the
917 * fwnode, you'll get fwnode referring to EP40 under ISP.
919 * The same example in DT syntax would look like this:
922 * compatible = "nokia,smia";
928 * remote-endpoint = <&isp 4 0>;
939 * remote-endpoint = <&cam 0 0>;
945 * Return: 0 on success
946 * -ENOENT if no entries (or the property itself) were found
947 * -EINVAL if property parsing otherwise failed
948 * -ENOMEM if memory allocation failed
950 static struct fwnode_handle *
951 v4l2_fwnode_reference_get_int_prop(struct fwnode_handle *fwnode,
954 const char * const *props,
957 struct fwnode_reference_args fwnode_args;
958 u64 *args = fwnode_args.args;
959 struct fwnode_handle *child;
963 * Obtain remote fwnode as well as the integer arguments.
965 * Note that right now both -ENODATA and -ENOENT may signal
966 * out-of-bounds access. Return -ENOENT in that case.
968 ret = fwnode_property_get_reference_args(fwnode, prop, NULL, nprops,
969 index, &fwnode_args);
971 return ERR_PTR(ret == -ENODATA ? -ENOENT : ret);
974 * Find a node in the tree under the referred fwnode corresponding to
975 * the integer arguments.
977 fwnode = fwnode_args.fwnode;
981 /* Loop over all child nodes under fwnode. */
982 fwnode_for_each_child_node(fwnode, child) {
983 if (fwnode_property_read_u32(child, *props, &val))
986 /* Found property, see if its value matches. */
991 fwnode_handle_put(fwnode);
993 /* No property found; return an error here. */
995 fwnode = ERR_PTR(-ENOENT);
1007 struct v4l2_fwnode_int_props {
1009 const char * const *props;
1010 unsigned int nprops;
1014 * v4l2_fwnode_reference_parse_int_props - parse references for async
1016 * @dev: struct device pointer
1017 * @notifier: notifier for @dev
1018 * @prop: the name of the property
1019 * @props: the array of integer property names
1020 * @nprops: the number of integer properties
1022 * Use v4l2_fwnode_reference_get_int_prop to find fwnodes through reference in
1023 * property @prop with integer arguments with child nodes matching in properties
1024 * @props. Then, set up V4L2 async sub-devices for those fwnodes in the notifier
1027 * While it is technically possible to use this function on DT, it is only
1028 * meaningful on ACPI. On Device tree you can refer to any node in the tree but
1029 * on ACPI the references are limited to devices.
1031 * Return: 0 on success
1032 * -ENOENT if no entries (or the property itself) were found
1033 * -EINVAL if property parsing otherwisefailed
1034 * -ENOMEM if memory allocation failed
1037 v4l2_fwnode_reference_parse_int_props(struct device *dev,
1038 struct v4l2_async_notifier *notifier,
1039 const struct v4l2_fwnode_int_props *p)
1041 struct fwnode_handle *fwnode;
1044 const char *prop = p->name;
1045 const char * const *props = p->props;
1046 unsigned int nprops = p->nprops;
1050 fwnode = v4l2_fwnode_reference_get_int_prop(dev_fwnode(dev),
1053 if (IS_ERR(fwnode)) {
1055 * Note that right now both -ENODATA and -ENOENT may
1056 * signal out-of-bounds access. Return the error in
1057 * cases other than that.
1059 if (PTR_ERR(fwnode) != -ENOENT &&
1060 PTR_ERR(fwnode) != -ENODATA)
1061 return PTR_ERR(fwnode);
1064 fwnode_handle_put(fwnode);
1069 !IS_ERR((fwnode = v4l2_fwnode_reference_get_int_prop(dev_fwnode(dev),
1074 struct v4l2_async_subdev *asd;
1076 asd = v4l2_async_notifier_add_fwnode_subdev(notifier, fwnode,
1080 /* not an error if asd already exists */
1081 if (ret == -EEXIST) {
1082 fwnode_handle_put(fwnode);
1090 return PTR_ERR(fwnode) == -ENOENT ? 0 : PTR_ERR(fwnode);
1093 fwnode_handle_put(fwnode);
1097 int v4l2_async_notifier_parse_fwnode_sensor_common(struct device *dev,
1098 struct v4l2_async_notifier *notifier)
1100 static const char * const led_props[] = { "led" };
1101 static const struct v4l2_fwnode_int_props props[] = {
1102 { "flash-leds", led_props, ARRAY_SIZE(led_props) },
1103 { "lens-focus", NULL, 0 },
1107 for (i = 0; i < ARRAY_SIZE(props); i++) {
1110 if (props[i].props && is_acpi_node(dev_fwnode(dev)))
1111 ret = v4l2_fwnode_reference_parse_int_props(dev,
1115 ret = v4l2_fwnode_reference_parse(dev, notifier,
1117 if (ret && ret != -ENOENT) {
1118 dev_warn(dev, "parsing property \"%s\" failed (%d)\n",
1119 props[i].name, ret);
1126 EXPORT_SYMBOL_GPL(v4l2_async_notifier_parse_fwnode_sensor_common);
1128 int v4l2_async_register_subdev_sensor_common(struct v4l2_subdev *sd)
1130 struct v4l2_async_notifier *notifier;
1133 if (WARN_ON(!sd->dev))
1136 notifier = kzalloc(sizeof(*notifier), GFP_KERNEL);
1140 v4l2_async_notifier_init(notifier);
1142 ret = v4l2_async_notifier_parse_fwnode_sensor_common(sd->dev,
1147 ret = v4l2_async_subdev_notifier_register(sd, notifier);
1151 ret = v4l2_async_register_subdev(sd);
1153 goto out_unregister;
1155 sd->subdev_notifier = notifier;
1160 v4l2_async_notifier_unregister(notifier);
1163 v4l2_async_notifier_cleanup(notifier);
1168 EXPORT_SYMBOL_GPL(v4l2_async_register_subdev_sensor_common);
1170 int v4l2_async_register_fwnode_subdev(struct v4l2_subdev *sd,
1171 size_t asd_struct_size,
1172 unsigned int *ports,
1173 unsigned int num_ports,
1174 parse_endpoint_func parse_endpoint)
1176 struct v4l2_async_notifier *notifier;
1177 struct device *dev = sd->dev;
1178 struct fwnode_handle *fwnode;
1184 fwnode = dev_fwnode(dev);
1185 if (!fwnode_device_is_available(fwnode))
1188 notifier = kzalloc(sizeof(*notifier), GFP_KERNEL);
1192 v4l2_async_notifier_init(notifier);
1195 ret = v4l2_async_notifier_parse_fwnode_endpoints(dev, notifier,
1203 for (i = 0; i < num_ports; i++) {
1204 ret = v4l2_async_notifier_parse_fwnode_endpoints_by_port(dev, notifier, asd_struct_size, ports[i], parse_endpoint);
1210 ret = v4l2_async_subdev_notifier_register(sd, notifier);
1214 ret = v4l2_async_register_subdev(sd);
1216 goto out_unregister;
1218 sd->subdev_notifier = notifier;
1223 v4l2_async_notifier_unregister(notifier);
1225 v4l2_async_notifier_cleanup(notifier);
1230 EXPORT_SYMBOL_GPL(v4l2_async_register_fwnode_subdev);
1232 MODULE_LICENSE("GPL");