xref: /linux/drivers/mfd/mfd-core.c (revision 69050f8d6d075dc01af7a5f2f550a8067510366f)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * drivers/mfd/mfd-core.c
4  *
5  * core MFD support
6  * Copyright (c) 2006 Ian Molton
7  * Copyright (c) 2007,2008 Dmitry Baryshkov
8  */
9 
10 #include <linux/kernel.h>
11 #include <linux/platform_device.h>
12 #include <linux/acpi.h>
13 #include <linux/list.h>
14 #include <linux/property.h>
15 #include <linux/mfd/core.h>
16 #include <linux/pm_runtime.h>
17 #include <linux/slab.h>
18 #include <linux/module.h>
19 #include <linux/irqdomain.h>
20 #include <linux/of.h>
21 #include <linux/of_address.h>
22 #include <linux/regulator/consumer.h>
23 
24 static LIST_HEAD(mfd_of_node_list);
25 static DEFINE_MUTEX(mfd_of_node_mutex);
26 
27 struct mfd_of_node_entry {
28 	struct list_head list;
29 	struct device *dev;
30 	struct device_node *np;
31 };
32 
33 static const struct device_type mfd_dev_type = {
34 	.name	= "mfd_device",
35 };
36 
37 #if IS_ENABLED(CONFIG_ACPI)
38 struct match_ids_walk_data {
39 	struct acpi_device_id *ids;
40 	struct acpi_device *adev;
41 };
42 
43 static int match_device_ids(struct acpi_device *adev, void *data)
44 {
45 	struct match_ids_walk_data *wd = data;
46 
47 	if (!acpi_match_device_ids(adev, wd->ids)) {
48 		wd->adev = adev;
49 		return 1;
50 	}
51 
52 	return 0;
53 }
54 
55 static void mfd_acpi_add_device(const struct mfd_cell *cell,
56 				struct platform_device *pdev)
57 {
58 	const struct mfd_cell_acpi_match *match = cell->acpi_match;
59 	struct acpi_device *adev = NULL;
60 	struct acpi_device *parent;
61 
62 	parent = ACPI_COMPANION(pdev->dev.parent);
63 	if (!parent)
64 		return;
65 
66 	/*
67 	 * MFD child device gets its ACPI handle either from the ACPI device
68 	 * directly under the parent that matches the either _HID or _CID, or
69 	 * _ADR or it will use the parent handle if is no ID is given.
70 	 *
71 	 * Note that use of _ADR is a grey area in the ACPI specification,
72 	 * though at least Intel Galileo Gen 2 is using it to distinguish
73 	 * the children devices.
74 	 */
75 	if (match) {
76 		if (match->pnpid) {
77 			struct acpi_device_id ids[2] = {};
78 			struct match_ids_walk_data wd = {
79 				.adev = NULL,
80 				.ids = ids,
81 			};
82 
83 			strscpy(ids[0].id, match->pnpid, sizeof(ids[0].id));
84 			acpi_dev_for_each_child(parent, match_device_ids, &wd);
85 			adev = wd.adev;
86 		} else {
87 			adev = acpi_find_child_device(parent, match->adr, false);
88 		}
89 	}
90 
91 	device_set_node(&pdev->dev, acpi_fwnode_handle(adev ?: parent));
92 }
93 #else
94 static inline void mfd_acpi_add_device(const struct mfd_cell *cell,
95 				       struct platform_device *pdev)
96 {
97 }
98 #endif
99 
100 static int mfd_match_of_node_to_dev(struct platform_device *pdev,
101 				    struct device_node *np,
102 				    const struct mfd_cell *cell)
103 {
104 	struct mfd_of_node_entry *of_entry;
105 	u64 of_node_addr;
106 
107 	/* Skip if OF node has previously been allocated to a device */
108 	scoped_guard(mutex, &mfd_of_node_mutex) {
109 		list_for_each_entry(of_entry, &mfd_of_node_list, list)
110 			if (of_entry->np == np)
111 				return -EAGAIN;
112 	}
113 
114 	if (!cell->use_of_reg)
115 		/* No of_reg defined - allocate first free compatible match */
116 		goto allocate_of_node;
117 
118 	/* We only care about each node's first defined address */
119 	if (of_property_read_reg(np, 0, &of_node_addr, NULL))
120 		/* OF node does not contatin a 'reg' property to match to */
121 		return -EAGAIN;
122 
123 	if (cell->of_reg != of_node_addr)
124 		/* No match */
125 		return -EAGAIN;
126 
127 allocate_of_node:
128 	of_entry = kzalloc(sizeof(*of_entry), GFP_KERNEL);
129 	if (!of_entry)
130 		return -ENOMEM;
131 
132 	of_entry->dev = &pdev->dev;
133 	of_entry->np = of_node_get(np);
134 	scoped_guard(mutex, &mfd_of_node_mutex)
135 		list_add_tail(&of_entry->list, &mfd_of_node_list);
136 
137 	device_set_node(&pdev->dev, of_fwnode_handle(np));
138 	return 0;
139 }
140 
141 static int mfd_add_device(struct device *parent, int id,
142 			  const struct mfd_cell *cell,
143 			  struct resource *mem_base,
144 			  int irq_base, struct irq_domain *domain)
145 {
146 	struct resource *res;
147 	struct platform_device *pdev;
148 	struct mfd_of_node_entry *of_entry, *tmp;
149 	bool disabled = false;
150 	int ret = -ENOMEM;
151 	int platform_id;
152 	int r;
153 
154 	if (id == PLATFORM_DEVID_AUTO)
155 		platform_id = id;
156 	else
157 		platform_id = id + cell->id;
158 
159 	pdev = platform_device_alloc(cell->name, platform_id);
160 	if (!pdev)
161 		goto fail_alloc;
162 
163 	pdev->mfd_cell = kmemdup(cell, sizeof(*cell), GFP_KERNEL);
164 	if (!pdev->mfd_cell)
165 		goto fail_device;
166 
167 	res = kcalloc(cell->num_resources, sizeof(*res), GFP_KERNEL);
168 	if (!res)
169 		goto fail_device;
170 
171 	pdev->dev.parent = parent;
172 	pdev->dev.type = &mfd_dev_type;
173 	pdev->dev.dma_mask = parent->dma_mask;
174 	pdev->dev.dma_parms = parent->dma_parms;
175 	pdev->dev.coherent_dma_mask = parent->coherent_dma_mask;
176 
177 	ret = regulator_bulk_register_supply_alias(
178 			&pdev->dev, cell->parent_supplies,
179 			parent, cell->parent_supplies,
180 			cell->num_parent_supplies);
181 	if (ret < 0)
182 		goto fail_res;
183 
184 	if (IS_ENABLED(CONFIG_OF) && parent->of_node && cell->of_compatible) {
185 		for_each_child_of_node_scoped(parent->of_node, np) {
186 			if (of_device_is_compatible(np, cell->of_compatible)) {
187 				/* Skip 'disabled' devices */
188 				if (!of_device_is_available(np)) {
189 					disabled = true;
190 					continue;
191 				}
192 
193 				ret = mfd_match_of_node_to_dev(pdev, np, cell);
194 				if (ret == -EAGAIN)
195 					continue;
196 				if (ret)
197 					goto fail_alias;
198 
199 				goto match;
200 			}
201 		}
202 
203 		if (disabled) {
204 			/* Ignore 'disabled' devices error free */
205 			ret = 0;
206 			goto fail_alias;
207 		}
208 
209 match:
210 		if (!pdev->dev.of_node)
211 			pr_warn("%s: Failed to locate of_node [id: %d]\n",
212 				cell->name, platform_id);
213 	}
214 
215 	mfd_acpi_add_device(cell, pdev);
216 
217 	if (cell->pdata_size) {
218 		ret = platform_device_add_data(pdev,
219 					cell->platform_data, cell->pdata_size);
220 		if (ret)
221 			goto fail_of_entry;
222 	}
223 
224 	if (cell->swnode) {
225 		ret = device_add_software_node(&pdev->dev, cell->swnode);
226 		if (ret)
227 			goto fail_of_entry;
228 	}
229 
230 	for (r = 0; r < cell->num_resources; r++) {
231 		res[r].name = cell->resources[r].name;
232 		res[r].flags = cell->resources[r].flags;
233 
234 		/* Find out base to use */
235 		if ((cell->resources[r].flags & IORESOURCE_MEM) && mem_base) {
236 			res[r].parent = mem_base;
237 			res[r].start = mem_base->start +
238 				cell->resources[r].start;
239 			res[r].end = mem_base->start +
240 				cell->resources[r].end;
241 		} else if (cell->resources[r].flags & IORESOURCE_IRQ) {
242 			if (domain) {
243 				/* Unable to create mappings for IRQ ranges. */
244 				WARN_ON(cell->resources[r].start !=
245 					cell->resources[r].end);
246 				res[r].start = res[r].end = irq_create_mapping(
247 					domain, cell->resources[r].start);
248 			} else {
249 				res[r].start = irq_base +
250 					cell->resources[r].start;
251 				res[r].end   = irq_base +
252 					cell->resources[r].end;
253 			}
254 		} else {
255 			res[r].parent = cell->resources[r].parent;
256 			res[r].start = cell->resources[r].start;
257 			res[r].end   = cell->resources[r].end;
258 		}
259 
260 		if (!cell->ignore_resource_conflicts) {
261 			if (has_acpi_companion(&pdev->dev)) {
262 				ret = acpi_check_resource_conflict(&res[r]);
263 				if (ret)
264 					goto fail_res_conflict;
265 			}
266 		}
267 	}
268 
269 	ret = platform_device_add_resources(pdev, res, cell->num_resources);
270 	if (ret)
271 		goto fail_res_conflict;
272 
273 	ret = platform_device_add(pdev);
274 	if (ret)
275 		goto fail_res_conflict;
276 
277 	if (cell->pm_runtime_no_callbacks)
278 		pm_runtime_no_callbacks(&pdev->dev);
279 
280 	kfree(res);
281 
282 	return 0;
283 
284 fail_res_conflict:
285 	if (cell->swnode)
286 		device_remove_software_node(&pdev->dev);
287 fail_of_entry:
288 	scoped_guard(mutex, &mfd_of_node_mutex) {
289 		list_for_each_entry_safe(of_entry, tmp, &mfd_of_node_list, list)
290 			if (of_entry->dev == &pdev->dev) {
291 				list_del(&of_entry->list);
292 				kfree(of_entry);
293 			}
294 	}
295 fail_alias:
296 	regulator_bulk_unregister_supply_alias(&pdev->dev,
297 					       cell->parent_supplies,
298 					       cell->num_parent_supplies);
299 fail_res:
300 	kfree(res);
301 fail_device:
302 	platform_device_put(pdev);
303 fail_alloc:
304 	return ret;
305 }
306 
307 /**
308  * mfd_add_devices - register child devices
309  *
310  * @parent:	Pointer to parent device.
311  * @id:		Can be PLATFORM_DEVID_AUTO to let the Platform API take care
312  *		of device numbering, or will be added to a device's cell_id.
313  * @cells:	Array of (struct mfd_cell)s describing child devices.
314  * @n_devs:	Number of child devices to register.
315  * @mem_base:	Parent register range resource for child devices.
316  * @irq_base:	Base of the range of virtual interrupt numbers allocated for
317  *		this MFD device. Unused if @domain is specified.
318  * @domain:	Interrupt domain to create mappings for hardware interrupts.
319  */
320 int mfd_add_devices(struct device *parent, int id,
321 		    const struct mfd_cell *cells, int n_devs,
322 		    struct resource *mem_base,
323 		    int irq_base, struct irq_domain *domain)
324 {
325 	int i;
326 	int ret;
327 
328 	for (i = 0; i < n_devs; i++) {
329 		ret = mfd_add_device(parent, id, cells + i, mem_base,
330 				     irq_base, domain);
331 		if (ret)
332 			goto fail;
333 	}
334 
335 	return 0;
336 
337 fail:
338 	if (i)
339 		mfd_remove_devices(parent);
340 
341 	return ret;
342 }
343 EXPORT_SYMBOL(mfd_add_devices);
344 
345 static int mfd_remove_devices_fn(struct device *dev, void *data)
346 {
347 	struct platform_device *pdev;
348 	const struct mfd_cell *cell;
349 	struct mfd_of_node_entry *of_entry, *tmp;
350 	int *level = data;
351 
352 	if (dev->type != &mfd_dev_type)
353 		return 0;
354 
355 	pdev = to_platform_device(dev);
356 	cell = mfd_get_cell(pdev);
357 
358 	if (level && cell->level > *level)
359 		return 0;
360 
361 	if (cell->swnode)
362 		device_remove_software_node(&pdev->dev);
363 
364 	scoped_guard(mutex, &mfd_of_node_mutex) {
365 		list_for_each_entry_safe(of_entry, tmp, &mfd_of_node_list, list)
366 			if (of_entry->dev == &pdev->dev) {
367 				list_del(&of_entry->list);
368 				kfree(of_entry);
369 			}
370 	}
371 
372 	regulator_bulk_unregister_supply_alias(dev, cell->parent_supplies,
373 					       cell->num_parent_supplies);
374 
375 	platform_device_unregister(pdev);
376 	return 0;
377 }
378 
379 void mfd_remove_devices_late(struct device *parent)
380 {
381 	int level = MFD_DEP_LEVEL_HIGH;
382 
383 	device_for_each_child_reverse(parent, &level, mfd_remove_devices_fn);
384 }
385 EXPORT_SYMBOL(mfd_remove_devices_late);
386 
387 void mfd_remove_devices(struct device *parent)
388 {
389 	int level = MFD_DEP_LEVEL_NORMAL;
390 
391 	device_for_each_child_reverse(parent, &level, mfd_remove_devices_fn);
392 }
393 EXPORT_SYMBOL(mfd_remove_devices);
394 
395 static void devm_mfd_dev_release(struct device *dev, void *res)
396 {
397 	mfd_remove_devices(dev);
398 }
399 
400 /**
401  * devm_mfd_add_devices - Resource managed version of mfd_add_devices()
402  *
403  * Returns 0 on success or an appropriate negative error number on failure.
404  * All child-devices of the MFD will automatically be removed when it gets
405  * unbinded.
406  *
407  * @dev:	Pointer to parent device.
408  * @id:		Can be PLATFORM_DEVID_AUTO to let the Platform API take care
409  *		of device numbering, or will be added to a device's cell_id.
410  * @cells:	Array of (struct mfd_cell)s describing child devices.
411  * @n_devs:	Number of child devices to register.
412  * @mem_base:	Parent register range resource for child devices.
413  * @irq_base:	Base of the range of virtual interrupt numbers allocated for
414  *		this MFD device. Unused if @domain is specified.
415  * @domain:	Interrupt domain to create mappings for hardware interrupts.
416  */
417 int devm_mfd_add_devices(struct device *dev, int id,
418 			 const struct mfd_cell *cells, int n_devs,
419 			 struct resource *mem_base,
420 			 int irq_base, struct irq_domain *domain)
421 {
422 	struct device **ptr;
423 	int ret;
424 
425 	ptr = devres_alloc(devm_mfd_dev_release, sizeof(*ptr), GFP_KERNEL);
426 	if (!ptr)
427 		return -ENOMEM;
428 
429 	ret = mfd_add_devices(dev, id, cells, n_devs, mem_base,
430 			      irq_base, domain);
431 	if (ret < 0) {
432 		devres_free(ptr);
433 		return ret;
434 	}
435 
436 	*ptr = dev;
437 	devres_add(dev, ptr);
438 
439 	return ret;
440 }
441 EXPORT_SYMBOL(devm_mfd_add_devices);
442 
443 MODULE_DESCRIPTION("Core MFD support");
444 MODULE_LICENSE("GPL");
445 MODULE_AUTHOR("Ian Molton, Dmitry Baryshkov");
446