xref: /openbmc/linux/drivers/mfd/mfd-core.c (revision fe4549b1)
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 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 	ACPI_COMPANION_SET(&pdev->dev, 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 	pdev->dev.of_node = np;
135 	pdev->dev.fwnode = &np->fwnode;
136 #endif
137 	return 0;
138 }
139 
140 static int mfd_add_device(struct device *parent, int id,
141 			  const struct mfd_cell *cell,
142 			  struct resource *mem_base,
143 			  int irq_base, struct irq_domain *domain)
144 {
145 	struct resource *res;
146 	struct platform_device *pdev;
147 	struct device_node *np = NULL;
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(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 				of_node_put(np);
197 				if (ret)
198 					goto fail_alias;
199 
200 				goto match;
201 			}
202 		}
203 
204 		if (disabled) {
205 			/* Ignore 'disabled' devices error free */
206 			ret = 0;
207 			goto fail_alias;
208 		}
209 
210 match:
211 		if (!pdev->dev.of_node)
212 			pr_warn("%s: Failed to locate of_node [id: %d]\n",
213 				cell->name, platform_id);
214 	}
215 
216 	mfd_acpi_add_device(cell, pdev);
217 
218 	if (cell->pdata_size) {
219 		ret = platform_device_add_data(pdev,
220 					cell->platform_data, cell->pdata_size);
221 		if (ret)
222 			goto fail_of_entry;
223 	}
224 
225 	if (cell->swnode) {
226 		ret = device_add_software_node(&pdev->dev, cell->swnode);
227 		if (ret)
228 			goto fail_of_entry;
229 	}
230 
231 	for (r = 0; r < cell->num_resources; r++) {
232 		res[r].name = cell->resources[r].name;
233 		res[r].flags = cell->resources[r].flags;
234 
235 		/* Find out base to use */
236 		if ((cell->resources[r].flags & IORESOURCE_MEM) && mem_base) {
237 			res[r].parent = mem_base;
238 			res[r].start = mem_base->start +
239 				cell->resources[r].start;
240 			res[r].end = mem_base->start +
241 				cell->resources[r].end;
242 		} else if (cell->resources[r].flags & IORESOURCE_IRQ) {
243 			if (domain) {
244 				/* Unable to create mappings for IRQ ranges. */
245 				WARN_ON(cell->resources[r].start !=
246 					cell->resources[r].end);
247 				res[r].start = res[r].end = irq_create_mapping(
248 					domain, cell->resources[r].start);
249 			} else {
250 				res[r].start = irq_base +
251 					cell->resources[r].start;
252 				res[r].end   = irq_base +
253 					cell->resources[r].end;
254 			}
255 		} else {
256 			res[r].parent = cell->resources[r].parent;
257 			res[r].start = cell->resources[r].start;
258 			res[r].end   = cell->resources[r].end;
259 		}
260 
261 		if (!cell->ignore_resource_conflicts) {
262 			if (has_acpi_companion(&pdev->dev)) {
263 				ret = acpi_check_resource_conflict(&res[r]);
264 				if (ret)
265 					goto fail_res_conflict;
266 			}
267 		}
268 	}
269 
270 	ret = platform_device_add_resources(pdev, res, cell->num_resources);
271 	if (ret)
272 		goto fail_res_conflict;
273 
274 	ret = platform_device_add(pdev);
275 	if (ret)
276 		goto fail_res_conflict;
277 
278 	if (cell->pm_runtime_no_callbacks)
279 		pm_runtime_no_callbacks(&pdev->dev);
280 
281 	kfree(res);
282 
283 	return 0;
284 
285 fail_res_conflict:
286 	if (cell->swnode)
287 		device_remove_software_node(&pdev->dev);
288 fail_of_entry:
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 fail_alias:
295 	regulator_bulk_unregister_supply_alias(&pdev->dev,
296 					       cell->parent_supplies,
297 					       cell->num_parent_supplies);
298 fail_res:
299 	kfree(res);
300 fail_device:
301 	platform_device_put(pdev);
302 fail_alloc:
303 	return ret;
304 }
305 
306 /**
307  * mfd_add_devices - register child devices
308  *
309  * @parent:	Pointer to parent device.
310  * @id:		Can be PLATFORM_DEVID_AUTO to let the Platform API take care
311  *		of device numbering, or will be added to a device's cell_id.
312  * @cells:	Array of (struct mfd_cell)s describing child devices.
313  * @n_devs:	Number of child devices to register.
314  * @mem_base:	Parent register range resource for child devices.
315  * @irq_base:	Base of the range of virtual interrupt numbers allocated for
316  *		this MFD device. Unused if @domain is specified.
317  * @domain:	Interrupt domain to create mappings for hardware interrupts.
318  */
319 int mfd_add_devices(struct device *parent, int id,
320 		    const struct mfd_cell *cells, int n_devs,
321 		    struct resource *mem_base,
322 		    int irq_base, struct irq_domain *domain)
323 {
324 	int i;
325 	int ret;
326 
327 	for (i = 0; i < n_devs; i++) {
328 		ret = mfd_add_device(parent, id, cells + i, mem_base,
329 				     irq_base, domain);
330 		if (ret)
331 			goto fail;
332 	}
333 
334 	return 0;
335 
336 fail:
337 	if (i)
338 		mfd_remove_devices(parent);
339 
340 	return ret;
341 }
342 EXPORT_SYMBOL(mfd_add_devices);
343 
344 static int mfd_remove_devices_fn(struct device *dev, void *data)
345 {
346 	struct platform_device *pdev;
347 	const struct mfd_cell *cell;
348 	struct mfd_of_node_entry *of_entry, *tmp;
349 	int *level = data;
350 
351 	if (dev->type != &mfd_dev_type)
352 		return 0;
353 
354 	pdev = to_platform_device(dev);
355 	cell = mfd_get_cell(pdev);
356 
357 	if (level && cell->level > *level)
358 		return 0;
359 
360 	if (cell->swnode)
361 		device_remove_software_node(&pdev->dev);
362 
363 	list_for_each_entry_safe(of_entry, tmp, &mfd_of_node_list, list)
364 		if (of_entry->dev == &pdev->dev) {
365 			list_del(&of_entry->list);
366 			kfree(of_entry);
367 		}
368 
369 	regulator_bulk_unregister_supply_alias(dev, cell->parent_supplies,
370 					       cell->num_parent_supplies);
371 
372 	platform_device_unregister(pdev);
373 	return 0;
374 }
375 
376 void mfd_remove_devices_late(struct device *parent)
377 {
378 	int level = MFD_DEP_LEVEL_HIGH;
379 
380 	device_for_each_child_reverse(parent, &level, mfd_remove_devices_fn);
381 }
382 EXPORT_SYMBOL(mfd_remove_devices_late);
383 
384 void mfd_remove_devices(struct device *parent)
385 {
386 	int level = MFD_DEP_LEVEL_NORMAL;
387 
388 	device_for_each_child_reverse(parent, &level, mfd_remove_devices_fn);
389 }
390 EXPORT_SYMBOL(mfd_remove_devices);
391 
392 static void devm_mfd_dev_release(struct device *dev, void *res)
393 {
394 	mfd_remove_devices(dev);
395 }
396 
397 /**
398  * devm_mfd_add_devices - Resource managed version of mfd_add_devices()
399  *
400  * Returns 0 on success or an appropriate negative error number on failure.
401  * All child-devices of the MFD will automatically be removed when it gets
402  * unbinded.
403  *
404  * @dev:	Pointer to parent device.
405  * @id:		Can be PLATFORM_DEVID_AUTO to let the Platform API take care
406  *		of device numbering, or will be added to a device's cell_id.
407  * @cells:	Array of (struct mfd_cell)s describing child devices.
408  * @n_devs:	Number of child devices to register.
409  * @mem_base:	Parent register range resource for child devices.
410  * @irq_base:	Base of the range of virtual interrupt numbers allocated for
411  *		this MFD device. Unused if @domain is specified.
412  * @domain:	Interrupt domain to create mappings for hardware interrupts.
413  */
414 int devm_mfd_add_devices(struct device *dev, int id,
415 			 const struct mfd_cell *cells, int n_devs,
416 			 struct resource *mem_base,
417 			 int irq_base, struct irq_domain *domain)
418 {
419 	struct device **ptr;
420 	int ret;
421 
422 	ptr = devres_alloc(devm_mfd_dev_release, sizeof(*ptr), GFP_KERNEL);
423 	if (!ptr)
424 		return -ENOMEM;
425 
426 	ret = mfd_add_devices(dev, id, cells, n_devs, mem_base,
427 			      irq_base, domain);
428 	if (ret < 0) {
429 		devres_free(ptr);
430 		return ret;
431 	}
432 
433 	*ptr = dev;
434 	devres_add(dev, ptr);
435 
436 	return ret;
437 }
438 EXPORT_SYMBOL(devm_mfd_add_devices);
439 
440 MODULE_LICENSE("GPL");
441 MODULE_AUTHOR("Ian Molton, Dmitry Baryshkov");
442