xref: /openbmc/linux/drivers/mfd/mfd-core.c (revision 12cecbf9)
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 int mfd_cell_enable(struct platform_device *pdev)
37 {
38 	const struct mfd_cell *cell = mfd_get_cell(pdev);
39 
40 	if (!cell->enable) {
41 		dev_dbg(&pdev->dev, "No .enable() call-back registered\n");
42 		return 0;
43 	}
44 
45 	return cell->enable(pdev);
46 }
47 EXPORT_SYMBOL(mfd_cell_enable);
48 
49 int mfd_cell_disable(struct platform_device *pdev)
50 {
51 	const struct mfd_cell *cell = mfd_get_cell(pdev);
52 
53 	if (!cell->disable) {
54 		dev_dbg(&pdev->dev, "No .disable() call-back registered\n");
55 		return 0;
56 	}
57 
58 	return cell->disable(pdev);
59 }
60 EXPORT_SYMBOL(mfd_cell_disable);
61 
62 #if IS_ENABLED(CONFIG_ACPI)
63 struct match_ids_walk_data {
64 	struct acpi_device_id *ids;
65 	struct acpi_device *adev;
66 };
67 
68 static int match_device_ids(struct acpi_device *adev, void *data)
69 {
70 	struct match_ids_walk_data *wd = data;
71 
72 	if (!acpi_match_device_ids(adev, wd->ids)) {
73 		wd->adev = adev;
74 		return 1;
75 	}
76 
77 	return 0;
78 }
79 
80 static void mfd_acpi_add_device(const struct mfd_cell *cell,
81 				struct platform_device *pdev)
82 {
83 	const struct mfd_cell_acpi_match *match = cell->acpi_match;
84 	struct acpi_device *adev = NULL;
85 	struct acpi_device *parent;
86 
87 	parent = ACPI_COMPANION(pdev->dev.parent);
88 	if (!parent)
89 		return;
90 
91 	/*
92 	 * MFD child device gets its ACPI handle either from the ACPI device
93 	 * directly under the parent that matches the either _HID or _CID, or
94 	 * _ADR or it will use the parent handle if is no ID is given.
95 	 *
96 	 * Note that use of _ADR is a grey area in the ACPI specification,
97 	 * though at least Intel Galileo Gen 2 is using it to distinguish
98 	 * the children devices.
99 	 */
100 	if (match) {
101 		if (match->pnpid) {
102 			struct acpi_device_id ids[2] = {};
103 			struct match_ids_walk_data wd = {
104 				.adev = NULL,
105 				.ids = ids,
106 			};
107 
108 			strlcpy(ids[0].id, match->pnpid, sizeof(ids[0].id));
109 			acpi_dev_for_each_child(parent, match_device_ids, &wd);
110 			adev = wd.adev;
111 		} else {
112 			adev = acpi_find_child_device(parent, match->adr, false);
113 		}
114 	}
115 
116 	ACPI_COMPANION_SET(&pdev->dev, adev ?: parent);
117 }
118 #else
119 static inline void mfd_acpi_add_device(const struct mfd_cell *cell,
120 				       struct platform_device *pdev)
121 {
122 }
123 #endif
124 
125 static int mfd_match_of_node_to_dev(struct platform_device *pdev,
126 				    struct device_node *np,
127 				    const struct mfd_cell *cell)
128 {
129 #if IS_ENABLED(CONFIG_OF)
130 	struct mfd_of_node_entry *of_entry;
131 	const __be32 *reg;
132 	u64 of_node_addr;
133 
134 	/* Skip if OF node has previously been allocated to a device */
135 	list_for_each_entry(of_entry, &mfd_of_node_list, list)
136 		if (of_entry->np == np)
137 			return -EAGAIN;
138 
139 	if (!cell->use_of_reg)
140 		/* No of_reg defined - allocate first free compatible match */
141 		goto allocate_of_node;
142 
143 	/* We only care about each node's first defined address */
144 	reg = of_get_address(np, 0, NULL, NULL);
145 	if (!reg)
146 		/* OF node does not contatin a 'reg' property to match to */
147 		return -EAGAIN;
148 
149 	of_node_addr = of_read_number(reg, of_n_addr_cells(np));
150 
151 	if (cell->of_reg != of_node_addr)
152 		/* No match */
153 		return -EAGAIN;
154 
155 allocate_of_node:
156 	of_entry = kzalloc(sizeof(*of_entry), GFP_KERNEL);
157 	if (!of_entry)
158 		return -ENOMEM;
159 
160 	of_entry->dev = &pdev->dev;
161 	of_entry->np = np;
162 	list_add_tail(&of_entry->list, &mfd_of_node_list);
163 
164 	pdev->dev.of_node = np;
165 	pdev->dev.fwnode = &np->fwnode;
166 #endif
167 	return 0;
168 }
169 
170 static int mfd_add_device(struct device *parent, int id,
171 			  const struct mfd_cell *cell,
172 			  struct resource *mem_base,
173 			  int irq_base, struct irq_domain *domain)
174 {
175 	struct resource *res;
176 	struct platform_device *pdev;
177 	struct device_node *np = NULL;
178 	struct mfd_of_node_entry *of_entry, *tmp;
179 	int ret = -ENOMEM;
180 	int platform_id;
181 	int r;
182 
183 	if (id == PLATFORM_DEVID_AUTO)
184 		platform_id = id;
185 	else
186 		platform_id = id + cell->id;
187 
188 	pdev = platform_device_alloc(cell->name, platform_id);
189 	if (!pdev)
190 		goto fail_alloc;
191 
192 	pdev->mfd_cell = kmemdup(cell, sizeof(*cell), GFP_KERNEL);
193 	if (!pdev->mfd_cell)
194 		goto fail_device;
195 
196 	res = kcalloc(cell->num_resources, sizeof(*res), GFP_KERNEL);
197 	if (!res)
198 		goto fail_device;
199 
200 	pdev->dev.parent = parent;
201 	pdev->dev.type = &mfd_dev_type;
202 	pdev->dev.dma_mask = parent->dma_mask;
203 	pdev->dev.dma_parms = parent->dma_parms;
204 	pdev->dev.coherent_dma_mask = parent->coherent_dma_mask;
205 
206 	ret = regulator_bulk_register_supply_alias(
207 			&pdev->dev, cell->parent_supplies,
208 			parent, cell->parent_supplies,
209 			cell->num_parent_supplies);
210 	if (ret < 0)
211 		goto fail_res;
212 
213 	if (IS_ENABLED(CONFIG_OF) && parent->of_node && cell->of_compatible) {
214 		for_each_child_of_node(parent->of_node, np) {
215 			if (of_device_is_compatible(np, cell->of_compatible)) {
216 				/* Ignore 'disabled' devices error free */
217 				if (!of_device_is_available(np)) {
218 					of_node_put(np);
219 					ret = 0;
220 					goto fail_alias;
221 				}
222 
223 				ret = mfd_match_of_node_to_dev(pdev, np, cell);
224 				if (ret == -EAGAIN)
225 					continue;
226 				of_node_put(np);
227 				if (ret)
228 					goto fail_alias;
229 
230 				break;
231 			}
232 		}
233 
234 		if (!pdev->dev.of_node)
235 			pr_warn("%s: Failed to locate of_node [id: %d]\n",
236 				cell->name, platform_id);
237 	}
238 
239 	mfd_acpi_add_device(cell, pdev);
240 
241 	if (cell->pdata_size) {
242 		ret = platform_device_add_data(pdev,
243 					cell->platform_data, cell->pdata_size);
244 		if (ret)
245 			goto fail_of_entry;
246 	}
247 
248 	if (cell->swnode) {
249 		ret = device_add_software_node(&pdev->dev, cell->swnode);
250 		if (ret)
251 			goto fail_of_entry;
252 	}
253 
254 	for (r = 0; r < cell->num_resources; r++) {
255 		res[r].name = cell->resources[r].name;
256 		res[r].flags = cell->resources[r].flags;
257 
258 		/* Find out base to use */
259 		if ((cell->resources[r].flags & IORESOURCE_MEM) && mem_base) {
260 			res[r].parent = mem_base;
261 			res[r].start = mem_base->start +
262 				cell->resources[r].start;
263 			res[r].end = mem_base->start +
264 				cell->resources[r].end;
265 		} else if (cell->resources[r].flags & IORESOURCE_IRQ) {
266 			if (domain) {
267 				/* Unable to create mappings for IRQ ranges. */
268 				WARN_ON(cell->resources[r].start !=
269 					cell->resources[r].end);
270 				res[r].start = res[r].end = irq_create_mapping(
271 					domain, cell->resources[r].start);
272 			} else {
273 				res[r].start = irq_base +
274 					cell->resources[r].start;
275 				res[r].end   = irq_base +
276 					cell->resources[r].end;
277 			}
278 		} else {
279 			res[r].parent = cell->resources[r].parent;
280 			res[r].start = cell->resources[r].start;
281 			res[r].end   = cell->resources[r].end;
282 		}
283 
284 		if (!cell->ignore_resource_conflicts) {
285 			if (has_acpi_companion(&pdev->dev)) {
286 				ret = acpi_check_resource_conflict(&res[r]);
287 				if (ret)
288 					goto fail_res_conflict;
289 			}
290 		}
291 	}
292 
293 	ret = platform_device_add_resources(pdev, res, cell->num_resources);
294 	if (ret)
295 		goto fail_res_conflict;
296 
297 	ret = platform_device_add(pdev);
298 	if (ret)
299 		goto fail_res_conflict;
300 
301 	if (cell->pm_runtime_no_callbacks)
302 		pm_runtime_no_callbacks(&pdev->dev);
303 
304 	kfree(res);
305 
306 	return 0;
307 
308 fail_res_conflict:
309 	if (cell->swnode)
310 		device_remove_software_node(&pdev->dev);
311 fail_of_entry:
312 	list_for_each_entry_safe(of_entry, tmp, &mfd_of_node_list, list)
313 		if (of_entry->dev == &pdev->dev) {
314 			list_del(&of_entry->list);
315 			kfree(of_entry);
316 		}
317 fail_alias:
318 	regulator_bulk_unregister_supply_alias(&pdev->dev,
319 					       cell->parent_supplies,
320 					       cell->num_parent_supplies);
321 fail_res:
322 	kfree(res);
323 fail_device:
324 	platform_device_put(pdev);
325 fail_alloc:
326 	return ret;
327 }
328 
329 /**
330  * mfd_add_devices - register child devices
331  *
332  * @parent:	Pointer to parent device.
333  * @id:		Can be PLATFORM_DEVID_AUTO to let the Platform API take care
334  *		of device numbering, or will be added to a device's cell_id.
335  * @cells:	Array of (struct mfd_cell)s describing child devices.
336  * @n_devs:	Number of child devices to register.
337  * @mem_base:	Parent register range resource for child devices.
338  * @irq_base:	Base of the range of virtual interrupt numbers allocated for
339  *		this MFD device. Unused if @domain is specified.
340  * @domain:	Interrupt domain to create mappings for hardware interrupts.
341  */
342 int mfd_add_devices(struct device *parent, int id,
343 		    const struct mfd_cell *cells, int n_devs,
344 		    struct resource *mem_base,
345 		    int irq_base, struct irq_domain *domain)
346 {
347 	int i;
348 	int ret;
349 
350 	for (i = 0; i < n_devs; i++) {
351 		ret = mfd_add_device(parent, id, cells + i, mem_base,
352 				     irq_base, domain);
353 		if (ret)
354 			goto fail;
355 	}
356 
357 	return 0;
358 
359 fail:
360 	if (i)
361 		mfd_remove_devices(parent);
362 
363 	return ret;
364 }
365 EXPORT_SYMBOL(mfd_add_devices);
366 
367 static int mfd_remove_devices_fn(struct device *dev, void *data)
368 {
369 	struct platform_device *pdev;
370 	const struct mfd_cell *cell;
371 	int *level = data;
372 
373 	if (dev->type != &mfd_dev_type)
374 		return 0;
375 
376 	pdev = to_platform_device(dev);
377 	cell = mfd_get_cell(pdev);
378 
379 	if (level && cell->level > *level)
380 		return 0;
381 
382 	if (cell->swnode)
383 		device_remove_software_node(&pdev->dev);
384 
385 	regulator_bulk_unregister_supply_alias(dev, cell->parent_supplies,
386 					       cell->num_parent_supplies);
387 
388 	platform_device_unregister(pdev);
389 	return 0;
390 }
391 
392 void mfd_remove_devices_late(struct device *parent)
393 {
394 	int level = MFD_DEP_LEVEL_HIGH;
395 
396 	device_for_each_child_reverse(parent, &level, mfd_remove_devices_fn);
397 }
398 EXPORT_SYMBOL(mfd_remove_devices_late);
399 
400 void mfd_remove_devices(struct device *parent)
401 {
402 	int level = MFD_DEP_LEVEL_NORMAL;
403 
404 	device_for_each_child_reverse(parent, &level, mfd_remove_devices_fn);
405 }
406 EXPORT_SYMBOL(mfd_remove_devices);
407 
408 static void devm_mfd_dev_release(struct device *dev, void *res)
409 {
410 	mfd_remove_devices(dev);
411 }
412 
413 /**
414  * devm_mfd_add_devices - Resource managed version of mfd_add_devices()
415  *
416  * Returns 0 on success or an appropriate negative error number on failure.
417  * All child-devices of the MFD will automatically be removed when it gets
418  * unbinded.
419  *
420  * @dev:	Pointer to parent device.
421  * @id:		Can be PLATFORM_DEVID_AUTO to let the Platform API take care
422  *		of device numbering, or will be added to a device's cell_id.
423  * @cells:	Array of (struct mfd_cell)s describing child devices.
424  * @n_devs:	Number of child devices to register.
425  * @mem_base:	Parent register range resource for child devices.
426  * @irq_base:	Base of the range of virtual interrupt numbers allocated for
427  *		this MFD device. Unused if @domain is specified.
428  * @domain:	Interrupt domain to create mappings for hardware interrupts.
429  */
430 int devm_mfd_add_devices(struct device *dev, int id,
431 			 const struct mfd_cell *cells, int n_devs,
432 			 struct resource *mem_base,
433 			 int irq_base, struct irq_domain *domain)
434 {
435 	struct device **ptr;
436 	int ret;
437 
438 	ptr = devres_alloc(devm_mfd_dev_release, sizeof(*ptr), GFP_KERNEL);
439 	if (!ptr)
440 		return -ENOMEM;
441 
442 	ret = mfd_add_devices(dev, id, cells, n_devs, mem_base,
443 			      irq_base, domain);
444 	if (ret < 0) {
445 		devres_free(ptr);
446 		return ret;
447 	}
448 
449 	*ptr = dev;
450 	devres_add(dev, ptr);
451 
452 	return ret;
453 }
454 EXPORT_SYMBOL(devm_mfd_add_devices);
455 
456 MODULE_LICENSE("GPL");
457 MODULE_AUTHOR("Ian Molton, Dmitry Baryshkov");
458