1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * V4L2 fwnode binding parsing library
4  *
5  * The origins of the V4L2 fwnode library are in V4L2 OF library that
6  * formerly was located in v4l2-of.c.
7  *
8  * Copyright (c) 2016 Intel Corporation.
9  * Author: Sakari Ailus <sakari.ailus@linux.intel.com>
10  *
11  * Copyright (C) 2012 - 2013 Samsung Electronics Co., Ltd.
12  * Author: Sylwester Nawrocki <s.nawrocki@samsung.com>
13  *
14  * Copyright (C) 2012 Renesas Electronics Corp.
15  * Author: Guennadi Liakhovetski <g.liakhovetski@gmx.de>
16  */
17 #include <linux/acpi.h>
18 #include <linux/kernel.h>
19 #include <linux/mm.h>
20 #include <linux/module.h>
21 #include <linux/of.h>
22 #include <linux/property.h>
23 #include <linux/slab.h>
24 #include <linux/string.h>
25 #include <linux/types.h>
26 
27 #include <media/v4l2-async.h>
28 #include <media/v4l2-fwnode.h>
29 #include <media/v4l2-subdev.h>
30 
31 enum v4l2_fwnode_bus_type {
32 	V4L2_FWNODE_BUS_TYPE_GUESS = 0,
33 	V4L2_FWNODE_BUS_TYPE_CSI2_CPHY,
34 	V4L2_FWNODE_BUS_TYPE_CSI1,
35 	V4L2_FWNODE_BUS_TYPE_CCP2,
36 	V4L2_FWNODE_BUS_TYPE_CSI2_DPHY,
37 	V4L2_FWNODE_BUS_TYPE_PARALLEL,
38 	V4L2_FWNODE_BUS_TYPE_BT656,
39 	NR_OF_V4L2_FWNODE_BUS_TYPE,
40 };
41 
42 static const struct v4l2_fwnode_bus_conv {
43 	enum v4l2_fwnode_bus_type fwnode_bus_type;
44 	enum v4l2_mbus_type mbus_type;
45 	const char *name;
46 } buses[] = {
47 	{
48 		V4L2_FWNODE_BUS_TYPE_GUESS,
49 		V4L2_MBUS_UNKNOWN,
50 		"not specified",
51 	}, {
52 		V4L2_FWNODE_BUS_TYPE_CSI2_CPHY,
53 		V4L2_MBUS_CSI2_CPHY,
54 		"MIPI CSI-2 C-PHY",
55 	}, {
56 		V4L2_FWNODE_BUS_TYPE_CSI1,
57 		V4L2_MBUS_CSI1,
58 		"MIPI CSI-1",
59 	}, {
60 		V4L2_FWNODE_BUS_TYPE_CCP2,
61 		V4L2_MBUS_CCP2,
62 		"compact camera port 2",
63 	}, {
64 		V4L2_FWNODE_BUS_TYPE_CSI2_DPHY,
65 		V4L2_MBUS_CSI2_DPHY,
66 		"MIPI CSI-2 D-PHY",
67 	}, {
68 		V4L2_FWNODE_BUS_TYPE_PARALLEL,
69 		V4L2_MBUS_PARALLEL,
70 		"parallel",
71 	}, {
72 		V4L2_FWNODE_BUS_TYPE_BT656,
73 		V4L2_MBUS_BT656,
74 		"Bt.656",
75 	}
76 };
77 
78 static const struct v4l2_fwnode_bus_conv *
get_v4l2_fwnode_bus_conv_by_fwnode_bus(enum v4l2_fwnode_bus_type type)79 get_v4l2_fwnode_bus_conv_by_fwnode_bus(enum v4l2_fwnode_bus_type type)
80 {
81 	unsigned int i;
82 
83 	for (i = 0; i < ARRAY_SIZE(buses); i++)
84 		if (buses[i].fwnode_bus_type == type)
85 			return &buses[i];
86 
87 	return NULL;
88 }
89 
90 static enum v4l2_mbus_type
v4l2_fwnode_bus_type_to_mbus(enum v4l2_fwnode_bus_type type)91 v4l2_fwnode_bus_type_to_mbus(enum v4l2_fwnode_bus_type type)
92 {
93 	const struct v4l2_fwnode_bus_conv *conv =
94 		get_v4l2_fwnode_bus_conv_by_fwnode_bus(type);
95 
96 	return conv ? conv->mbus_type : V4L2_MBUS_INVALID;
97 }
98 
99 static const char *
v4l2_fwnode_bus_type_to_string(enum v4l2_fwnode_bus_type type)100 v4l2_fwnode_bus_type_to_string(enum v4l2_fwnode_bus_type type)
101 {
102 	const struct v4l2_fwnode_bus_conv *conv =
103 		get_v4l2_fwnode_bus_conv_by_fwnode_bus(type);
104 
105 	return conv ? conv->name : "not found";
106 }
107 
108 static const struct v4l2_fwnode_bus_conv *
get_v4l2_fwnode_bus_conv_by_mbus(enum v4l2_mbus_type type)109 get_v4l2_fwnode_bus_conv_by_mbus(enum v4l2_mbus_type type)
110 {
111 	unsigned int i;
112 
113 	for (i = 0; i < ARRAY_SIZE(buses); i++)
114 		if (buses[i].mbus_type == type)
115 			return &buses[i];
116 
117 	return NULL;
118 }
119 
120 static const char *
v4l2_fwnode_mbus_type_to_string(enum v4l2_mbus_type type)121 v4l2_fwnode_mbus_type_to_string(enum v4l2_mbus_type type)
122 {
123 	const struct v4l2_fwnode_bus_conv *conv =
124 		get_v4l2_fwnode_bus_conv_by_mbus(type);
125 
126 	return conv ? conv->name : "not found";
127 }
128 
v4l2_fwnode_endpoint_parse_csi2_bus(struct fwnode_handle *fwnode, struct v4l2_fwnode_endpoint *vep, enum v4l2_mbus_type bus_type)129 static int v4l2_fwnode_endpoint_parse_csi2_bus(struct fwnode_handle *fwnode,
130 					       struct v4l2_fwnode_endpoint *vep,
131 					       enum v4l2_mbus_type bus_type)
132 {
133 	struct v4l2_fwnode_bus_mipi_csi2 *bus = &vep->bus.mipi_csi2;
134 	bool have_clk_lane = false, have_data_lanes = false,
135 		have_lane_polarities = false;
136 	unsigned int flags = 0, lanes_used = 0;
137 	u32 array[1 + V4L2_FWNODE_CSI2_MAX_DATA_LANES];
138 	u32 clock_lane = 0;
139 	unsigned int num_data_lanes = 0;
140 	bool use_default_lane_mapping = false;
141 	unsigned int i;
142 	u32 v;
143 	int rval;
144 
145 	if (bus_type == V4L2_MBUS_CSI2_DPHY ||
146 	    bus_type == V4L2_MBUS_CSI2_CPHY) {
147 		use_default_lane_mapping = true;
148 
149 		num_data_lanes = min_t(u32, bus->num_data_lanes,
150 				       V4L2_FWNODE_CSI2_MAX_DATA_LANES);
151 
152 		clock_lane = bus->clock_lane;
153 		if (clock_lane)
154 			use_default_lane_mapping = false;
155 
156 		for (i = 0; i < num_data_lanes; i++) {
157 			array[i] = bus->data_lanes[i];
158 			if (array[i])
159 				use_default_lane_mapping = false;
160 		}
161 
162 		if (use_default_lane_mapping)
163 			pr_debug("no lane mapping given, using defaults\n");
164 	}
165 
166 	rval = fwnode_property_count_u32(fwnode, "data-lanes");
167 	if (rval > 0) {
168 		num_data_lanes =
169 			min_t(int, V4L2_FWNODE_CSI2_MAX_DATA_LANES, rval);
170 
171 		fwnode_property_read_u32_array(fwnode, "data-lanes", array,
172 					       num_data_lanes);
173 
174 		have_data_lanes = true;
175 		if (use_default_lane_mapping) {
176 			pr_debug("data-lanes property exists; disabling default mapping\n");
177 			use_default_lane_mapping = false;
178 		}
179 	}
180 
181 	for (i = 0; i < num_data_lanes; i++) {
182 		if (lanes_used & BIT(array[i])) {
183 			if (have_data_lanes || !use_default_lane_mapping)
184 				pr_warn("duplicated lane %u in data-lanes, using defaults\n",
185 					array[i]);
186 			use_default_lane_mapping = true;
187 		}
188 		lanes_used |= BIT(array[i]);
189 
190 		if (have_data_lanes)
191 			pr_debug("lane %u position %u\n", i, array[i]);
192 	}
193 
194 	rval = fwnode_property_count_u32(fwnode, "lane-polarities");
195 	if (rval > 0) {
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);
199 			return -EINVAL;
200 		}
201 
202 		have_lane_polarities = true;
203 	}
204 
205 	if (!fwnode_property_read_u32(fwnode, "clock-lanes", &v)) {
206 		clock_lane = v;
207 		pr_debug("clock lane position %u\n", v);
208 		have_clk_lane = true;
209 	}
210 
211 	if (have_clk_lane && lanes_used & BIT(clock_lane) &&
212 	    !use_default_lane_mapping) {
213 		pr_warn("duplicated lane %u in clock-lanes, using defaults\n",
214 			v);
215 		use_default_lane_mapping = true;
216 	}
217 
218 	if (fwnode_property_present(fwnode, "clock-noncontinuous")) {
219 		flags |= V4L2_MBUS_CSI2_NONCONTINUOUS_CLOCK;
220 		pr_debug("non-continuous clock\n");
221 	} else {
222 		flags |= V4L2_MBUS_CSI2_CONTINUOUS_CLOCK;
223 	}
224 
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)) {
228 		/* Only D-PHY has a clock lane. */
229 		unsigned int dfl_data_lane_index =
230 			bus_type == V4L2_MBUS_CSI2_DPHY;
231 
232 		bus->flags = flags;
233 		if (bus_type == V4L2_MBUS_UNKNOWN)
234 			vep->bus_type = V4L2_MBUS_CSI2_DPHY;
235 		bus->num_data_lanes = num_data_lanes;
236 
237 		if (use_default_lane_mapping) {
238 			bus->clock_lane = 0;
239 			for (i = 0; i < num_data_lanes; i++)
240 				bus->data_lanes[i] = dfl_data_lane_index + i;
241 		} else {
242 			bus->clock_lane = clock_lane;
243 			for (i = 0; i < num_data_lanes; i++)
244 				bus->data_lanes[i] = array[i];
245 		}
246 
247 		if (have_lane_polarities) {
248 			fwnode_property_read_u32_array(fwnode,
249 						       "lane-polarities", array,
250 						       1 + num_data_lanes);
251 
252 			for (i = 0; i < 1 + num_data_lanes; i++) {
253 				bus->lane_polarities[i] = array[i];
254 				pr_debug("lane %u polarity %sinverted",
255 					 i, array[i] ? "" : "not ");
256 			}
257 		} else {
258 			pr_debug("no lane polarities defined, assuming not inverted\n");
259 		}
260 	}
261 
262 	return 0;
263 }
264 
265 #define PARALLEL_MBUS_FLAGS (V4L2_MBUS_HSYNC_ACTIVE_HIGH |	\
266 			     V4L2_MBUS_HSYNC_ACTIVE_LOW |	\
267 			     V4L2_MBUS_VSYNC_ACTIVE_HIGH |	\
268 			     V4L2_MBUS_VSYNC_ACTIVE_LOW |	\
269 			     V4L2_MBUS_FIELD_EVEN_HIGH |	\
270 			     V4L2_MBUS_FIELD_EVEN_LOW)
271 
272 static void
v4l2_fwnode_endpoint_parse_parallel_bus(struct fwnode_handle *fwnode, struct v4l2_fwnode_endpoint *vep, enum v4l2_mbus_type bus_type)273 v4l2_fwnode_endpoint_parse_parallel_bus(struct fwnode_handle *fwnode,
274 					struct v4l2_fwnode_endpoint *vep,
275 					enum v4l2_mbus_type bus_type)
276 {
277 	struct v4l2_fwnode_bus_parallel *bus = &vep->bus.parallel;
278 	unsigned int flags = 0;
279 	u32 v;
280 
281 	if (bus_type == V4L2_MBUS_PARALLEL || bus_type == V4L2_MBUS_BT656)
282 		flags = bus->flags;
283 
284 	if (!fwnode_property_read_u32(fwnode, "hsync-active", &v)) {
285 		flags &= ~(V4L2_MBUS_HSYNC_ACTIVE_HIGH |
286 			   V4L2_MBUS_HSYNC_ACTIVE_LOW);
287 		flags |= v ? V4L2_MBUS_HSYNC_ACTIVE_HIGH :
288 			V4L2_MBUS_HSYNC_ACTIVE_LOW;
289 		pr_debug("hsync-active %s\n", v ? "high" : "low");
290 	}
291 
292 	if (!fwnode_property_read_u32(fwnode, "vsync-active", &v)) {
293 		flags &= ~(V4L2_MBUS_VSYNC_ACTIVE_HIGH |
294 			   V4L2_MBUS_VSYNC_ACTIVE_LOW);
295 		flags |= v ? V4L2_MBUS_VSYNC_ACTIVE_HIGH :
296 			V4L2_MBUS_VSYNC_ACTIVE_LOW;
297 		pr_debug("vsync-active %s\n", v ? "high" : "low");
298 	}
299 
300 	if (!fwnode_property_read_u32(fwnode, "field-even-active", &v)) {
301 		flags &= ~(V4L2_MBUS_FIELD_EVEN_HIGH |
302 			   V4L2_MBUS_FIELD_EVEN_LOW);
303 		flags |= v ? V4L2_MBUS_FIELD_EVEN_HIGH :
304 			V4L2_MBUS_FIELD_EVEN_LOW;
305 		pr_debug("field-even-active %s\n", v ? "high" : "low");
306 	}
307 
308 	if (!fwnode_property_read_u32(fwnode, "pclk-sample", &v)) {
309 		flags &= ~(V4L2_MBUS_PCLK_SAMPLE_RISING |
310 			   V4L2_MBUS_PCLK_SAMPLE_FALLING);
311 		flags |= v ? V4L2_MBUS_PCLK_SAMPLE_RISING :
312 			V4L2_MBUS_PCLK_SAMPLE_FALLING;
313 		pr_debug("pclk-sample %s\n", v ? "high" : "low");
314 	}
315 
316 	if (!fwnode_property_read_u32(fwnode, "data-active", &v)) {
317 		flags &= ~(V4L2_MBUS_DATA_ACTIVE_HIGH |
318 			   V4L2_MBUS_DATA_ACTIVE_LOW);
319 		flags |= v ? V4L2_MBUS_DATA_ACTIVE_HIGH :
320 			V4L2_MBUS_DATA_ACTIVE_LOW;
321 		pr_debug("data-active %s\n", v ? "high" : "low");
322 	}
323 
324 	if (fwnode_property_present(fwnode, "slave-mode")) {
325 		pr_debug("slave mode\n");
326 		flags &= ~V4L2_MBUS_MASTER;
327 		flags |= V4L2_MBUS_SLAVE;
328 	} else {
329 		flags &= ~V4L2_MBUS_SLAVE;
330 		flags |= V4L2_MBUS_MASTER;
331 	}
332 
333 	if (!fwnode_property_read_u32(fwnode, "bus-width", &v)) {
334 		bus->bus_width = v;
335 		pr_debug("bus-width %u\n", v);
336 	}
337 
338 	if (!fwnode_property_read_u32(fwnode, "data-shift", &v)) {
339 		bus->data_shift = v;
340 		pr_debug("data-shift %u\n", v);
341 	}
342 
343 	if (!fwnode_property_read_u32(fwnode, "sync-on-green-active", &v)) {
344 		flags &= ~(V4L2_MBUS_VIDEO_SOG_ACTIVE_HIGH |
345 			   V4L2_MBUS_VIDEO_SOG_ACTIVE_LOW);
346 		flags |= v ? V4L2_MBUS_VIDEO_SOG_ACTIVE_HIGH :
347 			V4L2_MBUS_VIDEO_SOG_ACTIVE_LOW;
348 		pr_debug("sync-on-green-active %s\n", v ? "high" : "low");
349 	}
350 
351 	if (!fwnode_property_read_u32(fwnode, "data-enable-active", &v)) {
352 		flags &= ~(V4L2_MBUS_DATA_ENABLE_HIGH |
353 			   V4L2_MBUS_DATA_ENABLE_LOW);
354 		flags |= v ? V4L2_MBUS_DATA_ENABLE_HIGH :
355 			V4L2_MBUS_DATA_ENABLE_LOW;
356 		pr_debug("data-enable-active %s\n", v ? "high" : "low");
357 	}
358 
359 	switch (bus_type) {
360 	default:
361 		bus->flags = flags;
362 		if (flags & PARALLEL_MBUS_FLAGS)
363 			vep->bus_type = V4L2_MBUS_PARALLEL;
364 		else
365 			vep->bus_type = V4L2_MBUS_BT656;
366 		break;
367 	case V4L2_MBUS_PARALLEL:
368 		vep->bus_type = V4L2_MBUS_PARALLEL;
369 		bus->flags = flags;
370 		break;
371 	case V4L2_MBUS_BT656:
372 		vep->bus_type = V4L2_MBUS_BT656;
373 		bus->flags = flags & ~PARALLEL_MBUS_FLAGS;
374 		break;
375 	}
376 }
377 
378 static void
v4l2_fwnode_endpoint_parse_csi1_bus(struct fwnode_handle *fwnode, struct v4l2_fwnode_endpoint *vep, enum v4l2_mbus_type bus_type)379 v4l2_fwnode_endpoint_parse_csi1_bus(struct fwnode_handle *fwnode,
380 				    struct v4l2_fwnode_endpoint *vep,
381 				    enum v4l2_mbus_type bus_type)
382 {
383 	struct v4l2_fwnode_bus_mipi_csi1 *bus = &vep->bus.mipi_csi1;
384 	u32 v;
385 
386 	if (!fwnode_property_read_u32(fwnode, "clock-inv", &v)) {
387 		bus->clock_inv = v;
388 		pr_debug("clock-inv %u\n", v);
389 	}
390 
391 	if (!fwnode_property_read_u32(fwnode, "strobe", &v)) {
392 		bus->strobe = v;
393 		pr_debug("strobe %u\n", v);
394 	}
395 
396 	if (!fwnode_property_read_u32(fwnode, "data-lanes", &v)) {
397 		bus->data_lane = v;
398 		pr_debug("data-lanes %u\n", v);
399 	}
400 
401 	if (!fwnode_property_read_u32(fwnode, "clock-lanes", &v)) {
402 		bus->clock_lane = v;
403 		pr_debug("clock-lanes %u\n", v);
404 	}
405 
406 	if (bus_type == V4L2_MBUS_CCP2)
407 		vep->bus_type = V4L2_MBUS_CCP2;
408 	else
409 		vep->bus_type = V4L2_MBUS_CSI1;
410 }
411 
__v4l2_fwnode_endpoint_parse(struct fwnode_handle *fwnode, struct v4l2_fwnode_endpoint *vep)412 static int __v4l2_fwnode_endpoint_parse(struct fwnode_handle *fwnode,
413 					struct v4l2_fwnode_endpoint *vep)
414 {
415 	u32 bus_type = V4L2_FWNODE_BUS_TYPE_GUESS;
416 	enum v4l2_mbus_type mbus_type;
417 	int rval;
418 
419 	if (vep->bus_type == V4L2_MBUS_UNKNOWN) {
420 		/* Zero fields from bus union to until the end */
421 		memset(&vep->bus, 0,
422 		       sizeof(*vep) - offsetof(typeof(*vep), bus));
423 	}
424 
425 	pr_debug("===== begin parsing endpoint %pfw\n", fwnode);
426 
427 	/*
428 	 * Zero the fwnode graph endpoint memory in case we don't end up parsing
429 	 * the endpoint.
430 	 */
431 	memset(&vep->base, 0, sizeof(vep->base));
432 
433 	fwnode_property_read_u32(fwnode, "bus-type", &bus_type);
434 	pr_debug("fwnode video bus type %s (%u), mbus type %s (%u)\n",
435 		 v4l2_fwnode_bus_type_to_string(bus_type), bus_type,
436 		 v4l2_fwnode_mbus_type_to_string(vep->bus_type),
437 		 vep->bus_type);
438 	mbus_type = v4l2_fwnode_bus_type_to_mbus(bus_type);
439 	if (mbus_type == V4L2_MBUS_INVALID) {
440 		pr_debug("unsupported bus type %u\n", bus_type);
441 		return -EINVAL;
442 	}
443 
444 	if (vep->bus_type != V4L2_MBUS_UNKNOWN) {
445 		if (mbus_type != V4L2_MBUS_UNKNOWN &&
446 		    vep->bus_type != mbus_type) {
447 			pr_debug("expecting bus type %s\n",
448 				 v4l2_fwnode_mbus_type_to_string(vep->bus_type));
449 			return -ENXIO;
450 		}
451 	} else {
452 		vep->bus_type = mbus_type;
453 	}
454 
455 	switch (vep->bus_type) {
456 	case V4L2_MBUS_UNKNOWN:
457 		rval = v4l2_fwnode_endpoint_parse_csi2_bus(fwnode, vep,
458 							   V4L2_MBUS_UNKNOWN);
459 		if (rval)
460 			return rval;
461 
462 		if (vep->bus_type == V4L2_MBUS_UNKNOWN)
463 			v4l2_fwnode_endpoint_parse_parallel_bus(fwnode, vep,
464 								V4L2_MBUS_UNKNOWN);
465 
466 		pr_debug("assuming media bus type %s (%u)\n",
467 			 v4l2_fwnode_mbus_type_to_string(vep->bus_type),
468 			 vep->bus_type);
469 
470 		break;
471 	case V4L2_MBUS_CCP2:
472 	case V4L2_MBUS_CSI1:
473 		v4l2_fwnode_endpoint_parse_csi1_bus(fwnode, vep, vep->bus_type);
474 
475 		break;
476 	case V4L2_MBUS_CSI2_DPHY:
477 	case V4L2_MBUS_CSI2_CPHY:
478 		rval = v4l2_fwnode_endpoint_parse_csi2_bus(fwnode, vep,
479 							   vep->bus_type);
480 		if (rval)
481 			return rval;
482 
483 		break;
484 	case V4L2_MBUS_PARALLEL:
485 	case V4L2_MBUS_BT656:
486 		v4l2_fwnode_endpoint_parse_parallel_bus(fwnode, vep,
487 							vep->bus_type);
488 
489 		break;
490 	default:
491 		pr_warn("unsupported bus type %u\n", mbus_type);
492 		return -EINVAL;
493 	}
494 
495 	fwnode_graph_parse_endpoint(fwnode, &vep->base);
496 
497 	return 0;
498 }
499 
v4l2_fwnode_endpoint_parse(struct fwnode_handle *fwnode, struct v4l2_fwnode_endpoint *vep)500 int v4l2_fwnode_endpoint_parse(struct fwnode_handle *fwnode,
501 			       struct v4l2_fwnode_endpoint *vep)
502 {
503 	int ret;
504 
505 	ret = __v4l2_fwnode_endpoint_parse(fwnode, vep);
506 
507 	pr_debug("===== end parsing endpoint %pfw\n", fwnode);
508 
509 	return ret;
510 }
511 EXPORT_SYMBOL_GPL(v4l2_fwnode_endpoint_parse);
512 
v4l2_fwnode_endpoint_free(struct v4l2_fwnode_endpoint *vep)513 void v4l2_fwnode_endpoint_free(struct v4l2_fwnode_endpoint *vep)
514 {
515 	if (IS_ERR_OR_NULL(vep))
516 		return;
517 
518 	kfree(vep->link_frequencies);
519 	vep->link_frequencies = NULL;
520 }
521 EXPORT_SYMBOL_GPL(v4l2_fwnode_endpoint_free);
522 
v4l2_fwnode_endpoint_alloc_parse(struct fwnode_handle *fwnode, struct v4l2_fwnode_endpoint *vep)523 int v4l2_fwnode_endpoint_alloc_parse(struct fwnode_handle *fwnode,
524 				     struct v4l2_fwnode_endpoint *vep)
525 {
526 	int rval;
527 
528 	rval = __v4l2_fwnode_endpoint_parse(fwnode, vep);
529 	if (rval < 0)
530 		return rval;
531 
532 	rval = fwnode_property_count_u64(fwnode, "link-frequencies");
533 	if (rval > 0) {
534 		unsigned int i;
535 
536 		vep->link_frequencies =
537 			kmalloc_array(rval, sizeof(*vep->link_frequencies),
538 				      GFP_KERNEL);
539 		if (!vep->link_frequencies)
540 			return -ENOMEM;
541 
542 		vep->nr_of_link_frequencies = rval;
543 
544 		rval = fwnode_property_read_u64_array(fwnode,
545 						      "link-frequencies",
546 						      vep->link_frequencies,
547 						      vep->nr_of_link_frequencies);
548 		if (rval < 0) {
549 			v4l2_fwnode_endpoint_free(vep);
550 			return rval;
551 		}
552 
553 		for (i = 0; i < vep->nr_of_link_frequencies; i++)
554 			pr_debug("link-frequencies %u value %llu\n", i,
555 				 vep->link_frequencies[i]);
556 	}
557 
558 	pr_debug("===== end parsing endpoint %pfw\n", fwnode);
559 
560 	return 0;
561 }
562 EXPORT_SYMBOL_GPL(v4l2_fwnode_endpoint_alloc_parse);
563 
v4l2_fwnode_parse_link(struct fwnode_handle *fwnode, struct v4l2_fwnode_link *link)564 int v4l2_fwnode_parse_link(struct fwnode_handle *fwnode,
565 			   struct v4l2_fwnode_link *link)
566 {
567 	struct fwnode_endpoint fwep;
568 
569 	memset(link, 0, sizeof(*link));
570 
571 	fwnode_graph_parse_endpoint(fwnode, &fwep);
572 	link->local_id = fwep.id;
573 	link->local_port = fwep.port;
574 	link->local_node = fwnode_graph_get_port_parent(fwnode);
575 	if (!link->local_node)
576 		return -ENOLINK;
577 
578 	fwnode = fwnode_graph_get_remote_endpoint(fwnode);
579 	if (!fwnode)
580 		goto err_put_local_node;
581 
582 	fwnode_graph_parse_endpoint(fwnode, &fwep);
583 	link->remote_id = fwep.id;
584 	link->remote_port = fwep.port;
585 	link->remote_node = fwnode_graph_get_port_parent(fwnode);
586 	if (!link->remote_node)
587 		goto err_put_remote_endpoint;
588 
589 	return 0;
590 
591 err_put_remote_endpoint:
592 	fwnode_handle_put(fwnode);
593 
594 err_put_local_node:
595 	fwnode_handle_put(link->local_node);
596 
597 	return -ENOLINK;
598 }
599 EXPORT_SYMBOL_GPL(v4l2_fwnode_parse_link);
600 
v4l2_fwnode_put_link(struct v4l2_fwnode_link *link)601 void v4l2_fwnode_put_link(struct v4l2_fwnode_link *link)
602 {
603 	fwnode_handle_put(link->local_node);
604 	fwnode_handle_put(link->remote_node);
605 }
606 EXPORT_SYMBOL_GPL(v4l2_fwnode_put_link);
607 
608 static const struct v4l2_fwnode_connector_conv {
609 	enum v4l2_connector_type type;
610 	const char *compatible;
611 } connectors[] = {
612 	{
613 		.type = V4L2_CONN_COMPOSITE,
614 		.compatible = "composite-video-connector",
615 	}, {
616 		.type = V4L2_CONN_SVIDEO,
617 		.compatible = "svideo-connector",
618 	},
619 };
620 
621 static enum v4l2_connector_type
v4l2_fwnode_string_to_connector_type(const char *con_str)622 v4l2_fwnode_string_to_connector_type(const char *con_str)
623 {
624 	unsigned int i;
625 
626 	for (i = 0; i < ARRAY_SIZE(connectors); i++)
627 		if (!strcmp(con_str, connectors[i].compatible))
628 			return connectors[i].type;
629 
630 	return V4L2_CONN_UNKNOWN;
631 }
632 
633 static void
v4l2_fwnode_connector_parse_analog(struct fwnode_handle *fwnode, struct v4l2_fwnode_connector *vc)634 v4l2_fwnode_connector_parse_analog(struct fwnode_handle *fwnode,
635 				   struct v4l2_fwnode_connector *vc)
636 {
637 	u32 stds;
638 	int ret;
639 
640 	ret = fwnode_property_read_u32(fwnode, "sdtv-standards", &stds);
641 
642 	/* The property is optional. */
643 	vc->connector.analog.sdtv_stds = ret ? V4L2_STD_ALL : stds;
644 }
645 
v4l2_fwnode_connector_free(struct v4l2_fwnode_connector *connector)646 void v4l2_fwnode_connector_free(struct v4l2_fwnode_connector *connector)
647 {
648 	struct v4l2_connector_link *link, *tmp;
649 
650 	if (IS_ERR_OR_NULL(connector) || connector->type == V4L2_CONN_UNKNOWN)
651 		return;
652 
653 	list_for_each_entry_safe(link, tmp, &connector->links, head) {
654 		v4l2_fwnode_put_link(&link->fwnode_link);
655 		list_del(&link->head);
656 		kfree(link);
657 	}
658 
659 	kfree(connector->label);
660 	connector->label = NULL;
661 	connector->type = V4L2_CONN_UNKNOWN;
662 }
663 EXPORT_SYMBOL_GPL(v4l2_fwnode_connector_free);
664 
665 static enum v4l2_connector_type
v4l2_fwnode_get_connector_type(struct fwnode_handle *fwnode)666 v4l2_fwnode_get_connector_type(struct fwnode_handle *fwnode)
667 {
668 	const char *type_name;
669 	int err;
670 
671 	if (!fwnode)
672 		return V4L2_CONN_UNKNOWN;
673 
674 	/* The connector-type is stored within the compatible string. */
675 	err = fwnode_property_read_string(fwnode, "compatible", &type_name);
676 	if (err)
677 		return V4L2_CONN_UNKNOWN;
678 
679 	return v4l2_fwnode_string_to_connector_type(type_name);
680 }
681 
v4l2_fwnode_connector_parse(struct fwnode_handle *fwnode, struct v4l2_fwnode_connector *connector)682 int v4l2_fwnode_connector_parse(struct fwnode_handle *fwnode,
683 				struct v4l2_fwnode_connector *connector)
684 {
685 	struct fwnode_handle *connector_node;
686 	enum v4l2_connector_type connector_type;
687 	const char *label;
688 	int err;
689 
690 	if (!fwnode)
691 		return -EINVAL;
692 
693 	memset(connector, 0, sizeof(*connector));
694 
695 	INIT_LIST_HEAD(&connector->links);
696 
697 	connector_node = fwnode_graph_get_port_parent(fwnode);
698 	connector_type = v4l2_fwnode_get_connector_type(connector_node);
699 	if (connector_type == V4L2_CONN_UNKNOWN) {
700 		fwnode_handle_put(connector_node);
701 		connector_node = fwnode_graph_get_remote_port_parent(fwnode);
702 		connector_type = v4l2_fwnode_get_connector_type(connector_node);
703 	}
704 
705 	if (connector_type == V4L2_CONN_UNKNOWN) {
706 		pr_err("Unknown connector type\n");
707 		err = -ENOTCONN;
708 		goto out;
709 	}
710 
711 	connector->type = connector_type;
712 	connector->name = fwnode_get_name(connector_node);
713 	err = fwnode_property_read_string(connector_node, "label", &label);
714 	connector->label = err ? NULL : kstrdup_const(label, GFP_KERNEL);
715 
716 	/* Parse the connector specific properties. */
717 	switch (connector->type) {
718 	case V4L2_CONN_COMPOSITE:
719 	case V4L2_CONN_SVIDEO:
720 		v4l2_fwnode_connector_parse_analog(connector_node, connector);
721 		break;
722 	/* Avoid compiler warnings */
723 	case V4L2_CONN_UNKNOWN:
724 		break;
725 	}
726 
727 out:
728 	fwnode_handle_put(connector_node);
729 
730 	return err;
731 }
732 EXPORT_SYMBOL_GPL(v4l2_fwnode_connector_parse);
733 
v4l2_fwnode_connector_add_link(struct fwnode_handle *fwnode, struct v4l2_fwnode_connector *connector)734 int v4l2_fwnode_connector_add_link(struct fwnode_handle *fwnode,
735 				   struct v4l2_fwnode_connector *connector)
736 {
737 	struct fwnode_handle *connector_ep;
738 	struct v4l2_connector_link *link;
739 	int err;
740 
741 	if (!fwnode || !connector || connector->type == V4L2_CONN_UNKNOWN)
742 		return -EINVAL;
743 
744 	connector_ep = fwnode_graph_get_remote_endpoint(fwnode);
745 	if (!connector_ep)
746 		return -ENOTCONN;
747 
748 	link = kzalloc(sizeof(*link), GFP_KERNEL);
749 	if (!link) {
750 		err = -ENOMEM;
751 		goto err;
752 	}
753 
754 	err = v4l2_fwnode_parse_link(connector_ep, &link->fwnode_link);
755 	if (err)
756 		goto err;
757 
758 	fwnode_handle_put(connector_ep);
759 
760 	list_add(&link->head, &connector->links);
761 	connector->nr_of_links++;
762 
763 	return 0;
764 
765 err:
766 	kfree(link);
767 	fwnode_handle_put(connector_ep);
768 
769 	return err;
770 }
771 EXPORT_SYMBOL_GPL(v4l2_fwnode_connector_add_link);
772 
v4l2_fwnode_device_parse(struct device *dev, struct v4l2_fwnode_device_properties *props)773 int v4l2_fwnode_device_parse(struct device *dev,
774 			     struct v4l2_fwnode_device_properties *props)
775 {
776 	struct fwnode_handle *fwnode = dev_fwnode(dev);
777 	u32 val;
778 	int ret;
779 
780 	memset(props, 0, sizeof(*props));
781 
782 	props->orientation = V4L2_FWNODE_PROPERTY_UNSET;
783 	ret = fwnode_property_read_u32(fwnode, "orientation", &val);
784 	if (!ret) {
785 		switch (val) {
786 		case V4L2_FWNODE_ORIENTATION_FRONT:
787 		case V4L2_FWNODE_ORIENTATION_BACK:
788 		case V4L2_FWNODE_ORIENTATION_EXTERNAL:
789 			break;
790 		default:
791 			dev_warn(dev, "Unsupported device orientation: %u\n", val);
792 			return -EINVAL;
793 		}
794 
795 		props->orientation = val;
796 		dev_dbg(dev, "device orientation: %u\n", val);
797 	}
798 
799 	props->rotation = V4L2_FWNODE_PROPERTY_UNSET;
800 	ret = fwnode_property_read_u32(fwnode, "rotation", &val);
801 	if (!ret) {
802 		if (val >= 360) {
803 			dev_warn(dev, "Unsupported device rotation: %u\n", val);
804 			return -EINVAL;
805 		}
806 
807 		props->rotation = val;
808 		dev_dbg(dev, "device rotation: %u\n", val);
809 	}
810 
811 	return 0;
812 }
813 EXPORT_SYMBOL_GPL(v4l2_fwnode_device_parse);
814 
815 static int
v4l2_async_notifier_fwnode_parse_endpoint(struct device *dev, struct v4l2_async_notifier *notifier, struct fwnode_handle *endpoint, unsigned int asd_struct_size, parse_endpoint_func parse_endpoint)816 v4l2_async_notifier_fwnode_parse_endpoint(struct device *dev,
817 					  struct v4l2_async_notifier *notifier,
818 					  struct fwnode_handle *endpoint,
819 					  unsigned int asd_struct_size,
820 					  parse_endpoint_func parse_endpoint)
821 {
822 	struct v4l2_fwnode_endpoint vep = { .bus_type = 0 };
823 	struct v4l2_async_subdev *asd;
824 	int ret;
825 
826 	asd = kzalloc(asd_struct_size, GFP_KERNEL);
827 	if (!asd)
828 		return -ENOMEM;
829 
830 	asd->match_type = V4L2_ASYNC_MATCH_FWNODE;
831 	asd->match.fwnode =
832 		fwnode_graph_get_remote_port_parent(endpoint);
833 	if (!asd->match.fwnode) {
834 		dev_dbg(dev, "no remote endpoint found\n");
835 		ret = -ENOTCONN;
836 		goto out_err;
837 	}
838 
839 	ret = v4l2_fwnode_endpoint_alloc_parse(endpoint, &vep);
840 	if (ret) {
841 		dev_warn(dev, "unable to parse V4L2 fwnode endpoint (%d)\n",
842 			 ret);
843 		goto out_err;
844 	}
845 
846 	ret = parse_endpoint ? parse_endpoint(dev, &vep, asd) : 0;
847 	if (ret == -ENOTCONN)
848 		dev_dbg(dev, "ignoring port@%u/endpoint@%u\n", vep.base.port,
849 			vep.base.id);
850 	else if (ret < 0)
851 		dev_warn(dev,
852 			 "driver could not parse port@%u/endpoint@%u (%d)\n",
853 			 vep.base.port, vep.base.id, ret);
854 	v4l2_fwnode_endpoint_free(&vep);
855 	if (ret < 0)
856 		goto out_err;
857 
858 	ret = v4l2_async_notifier_add_subdev(notifier, asd);
859 	if (ret < 0) {
860 		/* not an error if asd already exists */
861 		if (ret == -EEXIST)
862 			ret = 0;
863 		goto out_err;
864 	}
865 
866 	return 0;
867 
868 out_err:
869 	fwnode_handle_put(asd->match.fwnode);
870 	kfree(asd);
871 
872 	return ret == -ENOTCONN ? 0 : ret;
873 }
874 
875 static int
__v4l2_async_notifier_parse_fwnode_ep(struct device *dev, struct v4l2_async_notifier *notifier, size_t asd_struct_size, unsigned int port, bool has_port, parse_endpoint_func parse_endpoint)876 __v4l2_async_notifier_parse_fwnode_ep(struct device *dev,
877 				      struct v4l2_async_notifier *notifier,
878 				      size_t asd_struct_size,
879 				      unsigned int port,
880 				      bool has_port,
881 				      parse_endpoint_func parse_endpoint)
882 {
883 	struct fwnode_handle *fwnode;
884 	int ret = 0;
885 
886 	if (WARN_ON(asd_struct_size < sizeof(struct v4l2_async_subdev)))
887 		return -EINVAL;
888 
889 	fwnode_graph_for_each_endpoint(dev_fwnode(dev), fwnode) {
890 		struct fwnode_handle *dev_fwnode;
891 		bool is_available;
892 
893 		dev_fwnode = fwnode_graph_get_port_parent(fwnode);
894 		is_available = fwnode_device_is_available(dev_fwnode);
895 		fwnode_handle_put(dev_fwnode);
896 		if (!is_available)
897 			continue;
898 
899 		if (has_port) {
900 			struct fwnode_endpoint ep;
901 
902 			ret = fwnode_graph_parse_endpoint(fwnode, &ep);
903 			if (ret)
904 				break;
905 
906 			if (ep.port != port)
907 				continue;
908 		}
909 
910 		ret = v4l2_async_notifier_fwnode_parse_endpoint(dev,
911 								notifier,
912 								fwnode,
913 								asd_struct_size,
914 								parse_endpoint);
915 		if (ret < 0)
916 			break;
917 	}
918 
919 	fwnode_handle_put(fwnode);
920 
921 	return ret;
922 }
923 
924 int
v4l2_async_notifier_parse_fwnode_endpoints(struct device *dev, struct v4l2_async_notifier *notifier, size_t asd_struct_size, parse_endpoint_func parse_endpoint)925 v4l2_async_notifier_parse_fwnode_endpoints(struct device *dev,
926 					   struct v4l2_async_notifier *notifier,
927 					   size_t asd_struct_size,
928 					   parse_endpoint_func parse_endpoint)
929 {
930 	return __v4l2_async_notifier_parse_fwnode_ep(dev, notifier,
931 						     asd_struct_size, 0,
932 						     false, parse_endpoint);
933 }
934 EXPORT_SYMBOL_GPL(v4l2_async_notifier_parse_fwnode_endpoints);
935 
936 int
v4l2_async_notifier_parse_fwnode_endpoints_by_port(struct device *dev, struct v4l2_async_notifier *notifier, size_t asd_struct_size, unsigned int port, parse_endpoint_func parse_endpoint)937 v4l2_async_notifier_parse_fwnode_endpoints_by_port(struct device *dev,
938 						   struct v4l2_async_notifier *notifier,
939 						   size_t asd_struct_size,
940 						   unsigned int port,
941 						   parse_endpoint_func parse_endpoint)
942 {
943 	return __v4l2_async_notifier_parse_fwnode_ep(dev, notifier,
944 						     asd_struct_size,
945 						     port, true,
946 						     parse_endpoint);
947 }
948 EXPORT_SYMBOL_GPL(v4l2_async_notifier_parse_fwnode_endpoints_by_port);
949 
950 /*
951  * v4l2_fwnode_reference_parse - parse references for async sub-devices
952  * @dev: the device node the properties of which are parsed for references
953  * @notifier: the async notifier where the async subdevs will be added
954  * @prop: the name of the property
955  *
956  * Return: 0 on success
957  *	   -ENOENT if no entries were found
958  *	   -ENOMEM if memory allocation failed
959  *	   -EINVAL if property parsing failed
960  */
v4l2_fwnode_reference_parse(struct device *dev, struct v4l2_async_notifier *notifier, const char *prop)961 static int v4l2_fwnode_reference_parse(struct device *dev,
962 				       struct v4l2_async_notifier *notifier,
963 				       const char *prop)
964 {
965 	struct fwnode_reference_args args;
966 	unsigned int index;
967 	int ret;
968 
969 	for (index = 0;
970 	     !(ret = fwnode_property_get_reference_args(dev_fwnode(dev),
971 							prop, NULL, 0,
972 							index, &args));
973 	     index++)
974 		fwnode_handle_put(args.fwnode);
975 
976 	if (!index)
977 		return -ENOENT;
978 
979 	/*
980 	 * Note that right now both -ENODATA and -ENOENT may signal
981 	 * out-of-bounds access. Return the error in cases other than that.
982 	 */
983 	if (ret != -ENOENT && ret != -ENODATA)
984 		return ret;
985 
986 	for (index = 0;
987 	     !fwnode_property_get_reference_args(dev_fwnode(dev), prop, NULL,
988 						 0, index, &args);
989 	     index++) {
990 		struct v4l2_async_subdev *asd;
991 
992 		asd = v4l2_async_notifier_add_fwnode_subdev(notifier,
993 							    args.fwnode,
994 							    sizeof(*asd));
995 		fwnode_handle_put(args.fwnode);
996 		if (IS_ERR(asd)) {
997 			/* not an error if asd already exists */
998 			if (PTR_ERR(asd) == -EEXIST)
999 				continue;
1000 
1001 			return PTR_ERR(asd);
1002 		}
1003 	}
1004 
1005 	return 0;
1006 }
1007 
1008 /*
1009  * v4l2_fwnode_reference_get_int_prop - parse a reference with integer
1010  *					arguments
1011  * @fwnode: fwnode to read @prop from
1012  * @notifier: notifier for @dev
1013  * @prop: the name of the property
1014  * @index: the index of the reference to get
1015  * @props: the array of integer property names
1016  * @nprops: the number of integer property names in @nprops
1017  *
1018  * First find an fwnode referred to by the reference at @index in @prop.
1019  *
1020  * Then under that fwnode, @nprops times, for each property in @props,
1021  * iteratively follow child nodes starting from fwnode such that they have the
1022  * property in @props array at the index of the child node distance from the
1023  * root node and the value of that property matching with the integer argument
1024  * of the reference, at the same index.
1025  *
1026  * The child fwnode reached at the end of the iteration is then returned to the
1027  * caller.
1028  *
1029  * The core reason for this is that you cannot refer to just any node in ACPI.
1030  * So to refer to an endpoint (easy in DT) you need to refer to a device, then
1031  * provide a list of (property name, property value) tuples where each tuple
1032  * uniquely identifies a child node. The first tuple identifies a child directly
1033  * underneath the device fwnode, the next tuple identifies a child node
1034  * underneath the fwnode identified by the previous tuple, etc. until you
1035  * reached the fwnode you need.
1036  *
1037  * THIS EXAMPLE EXISTS MERELY TO DOCUMENT THIS FUNCTION. DO NOT USE IT AS A
1038  * REFERENCE IN HOW ACPI TABLES SHOULD BE WRITTEN!! See documentation under
1039  * Documentation/firmware-guide/acpi/dsd/ instead and especially graph.txt,
1040  * data-node-references.txt and leds.txt .
1041  *
1042  *	Scope (\_SB.PCI0.I2C2)
1043  *	{
1044  *		Device (CAM0)
1045  *		{
1046  *			Name (_DSD, Package () {
1047  *				ToUUID("daffd814-6eba-4d8c-8a91-bc9bbf4aa301"),
1048  *				Package () {
1049  *					Package () {
1050  *						"compatible",
1051  *						Package () { "nokia,smia" }
1052  *					},
1053  *				},
1054  *				ToUUID("dbb8e3e6-5886-4ba6-8795-1319f52a966b"),
1055  *				Package () {
1056  *					Package () { "port0", "PRT0" },
1057  *				}
1058  *			})
1059  *			Name (PRT0, Package() {
1060  *				ToUUID("daffd814-6eba-4d8c-8a91-bc9bbf4aa301"),
1061  *				Package () {
1062  *					Package () { "port", 0 },
1063  *				},
1064  *				ToUUID("dbb8e3e6-5886-4ba6-8795-1319f52a966b"),
1065  *				Package () {
1066  *					Package () { "endpoint0", "EP00" },
1067  *				}
1068  *			})
1069  *			Name (EP00, Package() {
1070  *				ToUUID("daffd814-6eba-4d8c-8a91-bc9bbf4aa301"),
1071  *				Package () {
1072  *					Package () { "endpoint", 0 },
1073  *					Package () {
1074  *						"remote-endpoint",
1075  *						Package() {
1076  *							\_SB.PCI0.ISP, 4, 0
1077  *						}
1078  *					},
1079  *				}
1080  *			})
1081  *		}
1082  *	}
1083  *
1084  *	Scope (\_SB.PCI0)
1085  *	{
1086  *		Device (ISP)
1087  *		{
1088  *			Name (_DSD, Package () {
1089  *				ToUUID("dbb8e3e6-5886-4ba6-8795-1319f52a966b"),
1090  *				Package () {
1091  *					Package () { "port4", "PRT4" },
1092  *				}
1093  *			})
1094  *
1095  *			Name (PRT4, Package() {
1096  *				ToUUID("daffd814-6eba-4d8c-8a91-bc9bbf4aa301"),
1097  *				Package () {
1098  *					Package () { "port", 4 },
1099  *				},
1100  *				ToUUID("dbb8e3e6-5886-4ba6-8795-1319f52a966b"),
1101  *				Package () {
1102  *					Package () { "endpoint0", "EP40" },
1103  *				}
1104  *			})
1105  *
1106  *			Name (EP40, Package() {
1107  *				ToUUID("daffd814-6eba-4d8c-8a91-bc9bbf4aa301"),
1108  *				Package () {
1109  *					Package () { "endpoint", 0 },
1110  *					Package () {
1111  *						"remote-endpoint",
1112  *						Package () {
1113  *							\_SB.PCI0.I2C2.CAM0,
1114  *							0, 0
1115  *						}
1116  *					},
1117  *				}
1118  *			})
1119  *		}
1120  *	}
1121  *
1122  * From the EP40 node under ISP device, you could parse the graph remote
1123  * endpoint using v4l2_fwnode_reference_get_int_prop with these arguments:
1124  *
1125  *  @fwnode: fwnode referring to EP40 under ISP.
1126  *  @prop: "remote-endpoint"
1127  *  @index: 0
1128  *  @props: "port", "endpoint"
1129  *  @nprops: 2
1130  *
1131  * And you'd get back fwnode referring to EP00 under CAM0.
1132  *
1133  * The same works the other way around: if you use EP00 under CAM0 as the
1134  * fwnode, you'll get fwnode referring to EP40 under ISP.
1135  *
1136  * The same example in DT syntax would look like this:
1137  *
1138  * cam: cam0 {
1139  *	compatible = "nokia,smia";
1140  *
1141  *	port {
1142  *		port = <0>;
1143  *		endpoint {
1144  *			endpoint = <0>;
1145  *			remote-endpoint = <&isp 4 0>;
1146  *		};
1147  *	};
1148  * };
1149  *
1150  * isp: isp {
1151  *	ports {
1152  *		port@4 {
1153  *			port = <4>;
1154  *			endpoint {
1155  *				endpoint = <0>;
1156  *				remote-endpoint = <&cam 0 0>;
1157  *			};
1158  *		};
1159  *	};
1160  * };
1161  *
1162  * Return: 0 on success
1163  *	   -ENOENT if no entries (or the property itself) were found
1164  *	   -EINVAL if property parsing otherwise failed
1165  *	   -ENOMEM if memory allocation failed
1166  */
1167 static struct fwnode_handle *
v4l2_fwnode_reference_get_int_prop(struct fwnode_handle *fwnode, const char *prop, unsigned int index, const char * const *props, unsigned int nprops)1168 v4l2_fwnode_reference_get_int_prop(struct fwnode_handle *fwnode,
1169 				   const char *prop,
1170 				   unsigned int index,
1171 				   const char * const *props,
1172 				   unsigned int nprops)
1173 {
1174 	struct fwnode_reference_args fwnode_args;
1175 	u64 *args = fwnode_args.args;
1176 	struct fwnode_handle *child;
1177 	int ret;
1178 
1179 	/*
1180 	 * Obtain remote fwnode as well as the integer arguments.
1181 	 *
1182 	 * Note that right now both -ENODATA and -ENOENT may signal
1183 	 * out-of-bounds access. Return -ENOENT in that case.
1184 	 */
1185 	ret = fwnode_property_get_reference_args(fwnode, prop, NULL, nprops,
1186 						 index, &fwnode_args);
1187 	if (ret)
1188 		return ERR_PTR(ret == -ENODATA ? -ENOENT : ret);
1189 
1190 	/*
1191 	 * Find a node in the tree under the referred fwnode corresponding to
1192 	 * the integer arguments.
1193 	 */
1194 	fwnode = fwnode_args.fwnode;
1195 	while (nprops--) {
1196 		u32 val;
1197 
1198 		/* Loop over all child nodes under fwnode. */
1199 		fwnode_for_each_child_node(fwnode, child) {
1200 			if (fwnode_property_read_u32(child, *props, &val))
1201 				continue;
1202 
1203 			/* Found property, see if its value matches. */
1204 			if (val == *args)
1205 				break;
1206 		}
1207 
1208 		fwnode_handle_put(fwnode);
1209 
1210 		/* No property found; return an error here. */
1211 		if (!child) {
1212 			fwnode = ERR_PTR(-ENOENT);
1213 			break;
1214 		}
1215 
1216 		props++;
1217 		args++;
1218 		fwnode = child;
1219 	}
1220 
1221 	return fwnode;
1222 }
1223 
1224 struct v4l2_fwnode_int_props {
1225 	const char *name;
1226 	const char * const *props;
1227 	unsigned int nprops;
1228 };
1229 
1230 /*
1231  * v4l2_fwnode_reference_parse_int_props - parse references for async
1232  *					   sub-devices
1233  * @dev: struct device pointer
1234  * @notifier: notifier for @dev
1235  * @prop: the name of the property
1236  * @props: the array of integer property names
1237  * @nprops: the number of integer properties
1238  *
1239  * Use v4l2_fwnode_reference_get_int_prop to find fwnodes through reference in
1240  * property @prop with integer arguments with child nodes matching in properties
1241  * @props. Then, set up V4L2 async sub-devices for those fwnodes in the notifier
1242  * accordingly.
1243  *
1244  * While it is technically possible to use this function on DT, it is only
1245  * meaningful on ACPI. On Device tree you can refer to any node in the tree but
1246  * on ACPI the references are limited to devices.
1247  *
1248  * Return: 0 on success
1249  *	   -ENOENT if no entries (or the property itself) were found
1250  *	   -EINVAL if property parsing otherwisefailed
1251  *	   -ENOMEM if memory allocation failed
1252  */
1253 static int
v4l2_fwnode_reference_parse_int_props(struct device *dev, struct v4l2_async_notifier *notifier, const struct v4l2_fwnode_int_props *p)1254 v4l2_fwnode_reference_parse_int_props(struct device *dev,
1255 				      struct v4l2_async_notifier *notifier,
1256 				      const struct v4l2_fwnode_int_props *p)
1257 {
1258 	struct fwnode_handle *fwnode;
1259 	unsigned int index;
1260 	int ret;
1261 	const char *prop = p->name;
1262 	const char * const *props = p->props;
1263 	unsigned int nprops = p->nprops;
1264 
1265 	index = 0;
1266 	do {
1267 		fwnode = v4l2_fwnode_reference_get_int_prop(dev_fwnode(dev),
1268 							    prop, index,
1269 							    props, nprops);
1270 		if (IS_ERR(fwnode)) {
1271 			/*
1272 			 * Note that right now both -ENODATA and -ENOENT may
1273 			 * signal out-of-bounds access. Return the error in
1274 			 * cases other than that.
1275 			 */
1276 			if (PTR_ERR(fwnode) != -ENOENT &&
1277 			    PTR_ERR(fwnode) != -ENODATA)
1278 				return PTR_ERR(fwnode);
1279 			break;
1280 		}
1281 		fwnode_handle_put(fwnode);
1282 		index++;
1283 	} while (1);
1284 
1285 	for (index = 0;
1286 	     !IS_ERR((fwnode = v4l2_fwnode_reference_get_int_prop(dev_fwnode(dev),
1287 								  prop, index,
1288 								  props,
1289 								  nprops)));
1290 	     index++) {
1291 		struct v4l2_async_subdev *asd;
1292 
1293 		asd = v4l2_async_notifier_add_fwnode_subdev(notifier, fwnode,
1294 							    sizeof(*asd));
1295 		fwnode_handle_put(fwnode);
1296 		if (IS_ERR(asd)) {
1297 			ret = PTR_ERR(asd);
1298 			/* not an error if asd already exists */
1299 			if (ret == -EEXIST)
1300 				continue;
1301 
1302 			return PTR_ERR(asd);
1303 		}
1304 	}
1305 
1306 	return !fwnode || PTR_ERR(fwnode) == -ENOENT ? 0 : PTR_ERR(fwnode);
1307 }
1308 
v4l2_async_notifier_parse_fwnode_sensor_common(struct device *dev, struct v4l2_async_notifier *notifier)1309 int v4l2_async_notifier_parse_fwnode_sensor_common(struct device *dev,
1310 						   struct v4l2_async_notifier *notifier)
1311 {
1312 	static const char * const led_props[] = { "led" };
1313 	static const struct v4l2_fwnode_int_props props[] = {
1314 		{ "flash-leds", led_props, ARRAY_SIZE(led_props) },
1315 		{ "lens-focus", NULL, 0 },
1316 	};
1317 	unsigned int i;
1318 
1319 	for (i = 0; i < ARRAY_SIZE(props); i++) {
1320 		int ret;
1321 
1322 		if (props[i].props && is_acpi_node(dev_fwnode(dev)))
1323 			ret = v4l2_fwnode_reference_parse_int_props(dev,
1324 								    notifier,
1325 								    &props[i]);
1326 		else
1327 			ret = v4l2_fwnode_reference_parse(dev, notifier,
1328 							  props[i].name);
1329 		if (ret && ret != -ENOENT) {
1330 			dev_warn(dev, "parsing property \"%s\" failed (%d)\n",
1331 				 props[i].name, ret);
1332 			return ret;
1333 		}
1334 	}
1335 
1336 	return 0;
1337 }
1338 EXPORT_SYMBOL_GPL(v4l2_async_notifier_parse_fwnode_sensor_common);
1339 
v4l2_async_register_subdev_sensor_common(struct v4l2_subdev *sd)1340 int v4l2_async_register_subdev_sensor_common(struct v4l2_subdev *sd)
1341 {
1342 	struct v4l2_async_notifier *notifier;
1343 	int ret;
1344 
1345 	if (WARN_ON(!sd->dev))
1346 		return -ENODEV;
1347 
1348 	notifier = kzalloc(sizeof(*notifier), GFP_KERNEL);
1349 	if (!notifier)
1350 		return -ENOMEM;
1351 
1352 	v4l2_async_notifier_init(notifier);
1353 
1354 	ret = v4l2_async_notifier_parse_fwnode_sensor_common(sd->dev,
1355 							     notifier);
1356 	if (ret < 0)
1357 		goto out_cleanup;
1358 
1359 	ret = v4l2_async_subdev_notifier_register(sd, notifier);
1360 	if (ret < 0)
1361 		goto out_cleanup;
1362 
1363 	ret = v4l2_async_register_subdev(sd);
1364 	if (ret < 0)
1365 		goto out_unregister;
1366 
1367 	sd->subdev_notifier = notifier;
1368 
1369 	return 0;
1370 
1371 out_unregister:
1372 	v4l2_async_notifier_unregister(notifier);
1373 
1374 out_cleanup:
1375 	v4l2_async_notifier_cleanup(notifier);
1376 	kfree(notifier);
1377 
1378 	return ret;
1379 }
1380 EXPORT_SYMBOL_GPL(v4l2_async_register_subdev_sensor_common);
1381 
1382 MODULE_LICENSE("GPL");
1383 MODULE_AUTHOR("Sakari Ailus <sakari.ailus@linux.intel.com>");
1384 MODULE_AUTHOR("Sylwester Nawrocki <s.nawrocki@samsung.com>");
1385 MODULE_AUTHOR("Guennadi Liakhovetski <g.liakhovetski@gmx.de>");
1386