xref: /linux/drivers/mfd/mfd-core.c (revision c532de5a67a70f8533d495f8f2aaa9a0491c3ad0)
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 
26 struct mfd_of_node_entry {
27 	struct list_head list;
28 	struct device *dev;
29 	struct device_node *np;
30 };
31 
32 static const struct device_type mfd_dev_type = {
33 	.name	= "mfd_device",
34 };
35 
36 #if IS_ENABLED(CONFIG_ACPI)
37 struct match_ids_walk_data {
38 	struct acpi_device_id *ids;
39 	struct acpi_device *adev;
40 };
41 
42 static int match_device_ids(struct acpi_device *adev, void *data)
43 {
44 	struct match_ids_walk_data *wd = data;
45 
46 	if (!acpi_match_device_ids(adev, wd->ids)) {
47 		wd->adev = adev;
48 		return 1;
49 	}
50 
51 	return 0;
52 }
53 
54 static void mfd_acpi_add_device(const struct mfd_cell *cell,
55 				struct platform_device *pdev)
56 {
57 	const struct mfd_cell_acpi_match *match = cell->acpi_match;
58 	struct acpi_device *adev = NULL;
59 	struct acpi_device *parent;
60 
61 	parent = ACPI_COMPANION(pdev->dev.parent);
62 	if (!parent)
63 		return;
64 
65 	/*
66 	 * MFD child device gets its ACPI handle either from the ACPI device
67 	 * directly under the parent that matches the either _HID or _CID, or
68 	 * _ADR or it will use the parent handle if is no ID is given.
69 	 *
70 	 * Note that use of _ADR is a grey area in the ACPI specification,
71 	 * though at least Intel Galileo Gen 2 is using it to distinguish
72 	 * the children devices.
73 	 */
74 	if (match) {
75 		if (match->pnpid) {
76 			struct acpi_device_id ids[2] = {};
77 			struct match_ids_walk_data wd = {
78 				.adev = NULL,
79 				.ids = ids,
80 			};
81 
82 			strscpy(ids[0].id, match->pnpid, sizeof(ids[0].id));
83 			acpi_dev_for_each_child(parent, match_device_ids, &wd);
84 			adev = wd.adev;
85 		} else {
86 			adev = acpi_find_child_device(parent, match->adr, false);
87 		}
88 	}
89 
90 	device_set_node(&pdev->dev, acpi_fwnode_handle(adev ?: parent));
91 }
92 #else
93 static inline void mfd_acpi_add_device(const struct mfd_cell *cell,
94 				       struct platform_device *pdev)
95 {
96 }
97 #endif
98 
99 static int mfd_match_of_node_to_dev(struct platform_device *pdev,
100 				    struct device_node *np,
101 				    const struct mfd_cell *cell)
102 {
103 #if IS_ENABLED(CONFIG_OF)
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 	list_for_each_entry(of_entry, &mfd_of_node_list, list)
109 		if (of_entry->np == np)
110 			return -EAGAIN;
111 
112 	if (!cell->use_of_reg)
113 		/* No of_reg defined - allocate first free compatible match */
114 		goto allocate_of_node;
115 
116 	/* We only care about each node's first defined address */
117 	if (of_property_read_reg(np, 0, &of_node_addr, NULL))
118 		/* OF node does not contatin a 'reg' property to match to */
119 		return -EAGAIN;
120 
121 	if (cell->of_reg != of_node_addr)
122 		/* No match */
123 		return -EAGAIN;
124 
125 allocate_of_node:
126 	of_entry = kzalloc(sizeof(*of_entry), GFP_KERNEL);
127 	if (!of_entry)
128 		return -ENOMEM;
129 
130 	of_entry->dev = &pdev->dev;
131 	of_entry->np = np;
132 	list_add_tail(&of_entry->list, &mfd_of_node_list);
133 
134 	device_set_node(&pdev->dev, of_fwnode_handle(np));
135 #endif
136 	return 0;
137 }
138 
139 static int mfd_add_device(struct device *parent, int id,
140 			  const struct mfd_cell *cell,
141 			  struct resource *mem_base,
142 			  int irq_base, struct irq_domain *domain)
143 {
144 	struct resource *res;
145 	struct platform_device *pdev;
146 	struct device_node *np = NULL;
147 	struct mfd_of_node_entry *of_entry, *tmp;
148 	bool disabled = false;
149 	int ret = -ENOMEM;
150 	int platform_id;
151 	int r;
152 
153 	if (id == PLATFORM_DEVID_AUTO)
154 		platform_id = id;
155 	else
156 		platform_id = id + cell->id;
157 
158 	pdev = platform_device_alloc(cell->name, platform_id);
159 	if (!pdev)
160 		goto fail_alloc;
161 
162 	pdev->mfd_cell = kmemdup(cell, sizeof(*cell), GFP_KERNEL);
163 	if (!pdev->mfd_cell)
164 		goto fail_device;
165 
166 	res = kcalloc(cell->num_resources, sizeof(*res), GFP_KERNEL);
167 	if (!res)
168 		goto fail_device;
169 
170 	pdev->dev.parent = parent;
171 	pdev->dev.type = &mfd_dev_type;
172 	pdev->dev.dma_mask = parent->dma_mask;
173 	pdev->dev.dma_parms = parent->dma_parms;
174 	pdev->dev.coherent_dma_mask = parent->coherent_dma_mask;
175 
176 	ret = regulator_bulk_register_supply_alias(
177 			&pdev->dev, cell->parent_supplies,
178 			parent, cell->parent_supplies,
179 			cell->num_parent_supplies);
180 	if (ret < 0)
181 		goto fail_res;
182 
183 	if (IS_ENABLED(CONFIG_OF) && parent->of_node && cell->of_compatible) {
184 		for_each_child_of_node(parent->of_node, np) {
185 			if (of_device_is_compatible(np, cell->of_compatible)) {
186 				/* Skip 'disabled' devices */
187 				if (!of_device_is_available(np)) {
188 					disabled = true;
189 					continue;
190 				}
191 
192 				ret = mfd_match_of_node_to_dev(pdev, np, cell);
193 				if (ret == -EAGAIN)
194 					continue;
195 				of_node_put(np);
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 	list_for_each_entry_safe(of_entry, tmp, &mfd_of_node_list, list)
289 		if (of_entry->dev == &pdev->dev) {
290 			list_del(&of_entry->list);
291 			kfree(of_entry);
292 		}
293 fail_alias:
294 	regulator_bulk_unregister_supply_alias(&pdev->dev,
295 					       cell->parent_supplies,
296 					       cell->num_parent_supplies);
297 fail_res:
298 	kfree(res);
299 fail_device:
300 	platform_device_put(pdev);
301 fail_alloc:
302 	return ret;
303 }
304 
305 /**
306  * mfd_add_devices - register child devices
307  *
308  * @parent:	Pointer to parent device.
309  * @id:		Can be PLATFORM_DEVID_AUTO to let the Platform API take care
310  *		of device numbering, or will be added to a device's cell_id.
311  * @cells:	Array of (struct mfd_cell)s describing child devices.
312  * @n_devs:	Number of child devices to register.
313  * @mem_base:	Parent register range resource for child devices.
314  * @irq_base:	Base of the range of virtual interrupt numbers allocated for
315  *		this MFD device. Unused if @domain is specified.
316  * @domain:	Interrupt domain to create mappings for hardware interrupts.
317  */
318 int mfd_add_devices(struct device *parent, int id,
319 		    const struct mfd_cell *cells, int n_devs,
320 		    struct resource *mem_base,
321 		    int irq_base, struct irq_domain *domain)
322 {
323 	int i;
324 	int ret;
325 
326 	for (i = 0; i < n_devs; i++) {
327 		ret = mfd_add_device(parent, id, cells + i, mem_base,
328 				     irq_base, domain);
329 		if (ret)
330 			goto fail;
331 	}
332 
333 	return 0;
334 
335 fail:
336 	if (i)
337 		mfd_remove_devices(parent);
338 
339 	return ret;
340 }
341 EXPORT_SYMBOL(mfd_add_devices);
342 
343 static int mfd_remove_devices_fn(struct device *dev, void *data)
344 {
345 	struct platform_device *pdev;
346 	const struct mfd_cell *cell;
347 	struct mfd_of_node_entry *of_entry, *tmp;
348 	int *level = data;
349 
350 	if (dev->type != &mfd_dev_type)
351 		return 0;
352 
353 	pdev = to_platform_device(dev);
354 	cell = mfd_get_cell(pdev);
355 
356 	if (level && cell->level > *level)
357 		return 0;
358 
359 	if (cell->swnode)
360 		device_remove_software_node(&pdev->dev);
361 
362 	list_for_each_entry_safe(of_entry, tmp, &mfd_of_node_list, list)
363 		if (of_entry->dev == &pdev->dev) {
364 			list_del(&of_entry->list);
365 			kfree(of_entry);
366 		}
367 
368 	regulator_bulk_unregister_supply_alias(dev, cell->parent_supplies,
369 					       cell->num_parent_supplies);
370 
371 	platform_device_unregister(pdev);
372 	return 0;
373 }
374 
375 void mfd_remove_devices_late(struct device *parent)
376 {
377 	int level = MFD_DEP_LEVEL_HIGH;
378 
379 	device_for_each_child_reverse(parent, &level, mfd_remove_devices_fn);
380 }
381 EXPORT_SYMBOL(mfd_remove_devices_late);
382 
383 void mfd_remove_devices(struct device *parent)
384 {
385 	int level = MFD_DEP_LEVEL_NORMAL;
386 
387 	device_for_each_child_reverse(parent, &level, mfd_remove_devices_fn);
388 }
389 EXPORT_SYMBOL(mfd_remove_devices);
390 
391 static void devm_mfd_dev_release(struct device *dev, void *res)
392 {
393 	mfd_remove_devices(dev);
394 }
395 
396 /**
397  * devm_mfd_add_devices - Resource managed version of mfd_add_devices()
398  *
399  * Returns 0 on success or an appropriate negative error number on failure.
400  * All child-devices of the MFD will automatically be removed when it gets
401  * unbinded.
402  *
403  * @dev:	Pointer to parent device.
404  * @id:		Can be PLATFORM_DEVID_AUTO to let the Platform API take care
405  *		of device numbering, or will be added to a device's cell_id.
406  * @cells:	Array of (struct mfd_cell)s describing child devices.
407  * @n_devs:	Number of child devices to register.
408  * @mem_base:	Parent register range resource for child devices.
409  * @irq_base:	Base of the range of virtual interrupt numbers allocated for
410  *		this MFD device. Unused if @domain is specified.
411  * @domain:	Interrupt domain to create mappings for hardware interrupts.
412  */
413 int devm_mfd_add_devices(struct device *dev, int id,
414 			 const struct mfd_cell *cells, int n_devs,
415 			 struct resource *mem_base,
416 			 int irq_base, struct irq_domain *domain)
417 {
418 	struct device **ptr;
419 	int ret;
420 
421 	ptr = devres_alloc(devm_mfd_dev_release, sizeof(*ptr), GFP_KERNEL);
422 	if (!ptr)
423 		return -ENOMEM;
424 
425 	ret = mfd_add_devices(dev, id, cells, n_devs, mem_base,
426 			      irq_base, domain);
427 	if (ret < 0) {
428 		devres_free(ptr);
429 		return ret;
430 	}
431 
432 	*ptr = dev;
433 	devres_add(dev, ptr);
434 
435 	return ret;
436 }
437 EXPORT_SYMBOL(devm_mfd_add_devices);
438 
439 MODULE_DESCRIPTION("Core MFD support");
440 MODULE_LICENSE("GPL");
441 MODULE_AUTHOR("Ian Molton, Dmitry Baryshkov");
442