xref: /openbmc/linux/drivers/mfd/mfd-core.c (revision 31e67366)
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 static void mfd_acpi_add_device(const struct mfd_cell *cell,
64 				struct platform_device *pdev)
65 {
66 	const struct mfd_cell_acpi_match *match = cell->acpi_match;
67 	struct acpi_device *parent, *child;
68 	struct acpi_device *adev;
69 
70 	parent = ACPI_COMPANION(pdev->dev.parent);
71 	if (!parent)
72 		return;
73 
74 	/*
75 	 * MFD child device gets its ACPI handle either from the ACPI device
76 	 * directly under the parent that matches the either _HID or _CID, or
77 	 * _ADR or it will use the parent handle if is no ID is given.
78 	 *
79 	 * Note that use of _ADR is a grey area in the ACPI specification,
80 	 * though Intel Galileo Gen2 is using it to distinguish the children
81 	 * devices.
82 	 */
83 	adev = parent;
84 	if (match) {
85 		if (match->pnpid) {
86 			struct acpi_device_id ids[2] = {};
87 
88 			strlcpy(ids[0].id, match->pnpid, sizeof(ids[0].id));
89 			list_for_each_entry(child, &parent->children, node) {
90 				if (!acpi_match_device_ids(child, ids)) {
91 					adev = child;
92 					break;
93 				}
94 			}
95 		} else {
96 			unsigned long long adr;
97 			acpi_status status;
98 
99 			list_for_each_entry(child, &parent->children, node) {
100 				status = acpi_evaluate_integer(child->handle,
101 							       "_ADR", NULL,
102 							       &adr);
103 				if (ACPI_SUCCESS(status) && match->adr == adr) {
104 					adev = child;
105 					break;
106 				}
107 			}
108 		}
109 	}
110 
111 	ACPI_COMPANION_SET(&pdev->dev, adev);
112 }
113 #else
114 static inline void mfd_acpi_add_device(const struct mfd_cell *cell,
115 				       struct platform_device *pdev)
116 {
117 }
118 #endif
119 
120 static int mfd_match_of_node_to_dev(struct platform_device *pdev,
121 				    struct device_node *np,
122 				    const struct mfd_cell *cell)
123 {
124 #if IS_ENABLED(CONFIG_OF)
125 	struct mfd_of_node_entry *of_entry;
126 	const __be32 *reg;
127 	u64 of_node_addr;
128 
129 	/* Skip if OF node has previously been allocated to a device */
130 	list_for_each_entry(of_entry, &mfd_of_node_list, list)
131 		if (of_entry->np == np)
132 			return -EAGAIN;
133 
134 	if (!cell->use_of_reg)
135 		/* No of_reg defined - allocate first free compatible match */
136 		goto allocate_of_node;
137 
138 	/* We only care about each node's first defined address */
139 	reg = of_get_address(np, 0, NULL, NULL);
140 	if (!reg)
141 		/* OF node does not contatin a 'reg' property to match to */
142 		return -EAGAIN;
143 
144 	of_node_addr = of_read_number(reg, of_n_addr_cells(np));
145 
146 	if (cell->of_reg != of_node_addr)
147 		/* No match */
148 		return -EAGAIN;
149 
150 allocate_of_node:
151 	of_entry = kzalloc(sizeof(*of_entry), GFP_KERNEL);
152 	if (!of_entry)
153 		return -ENOMEM;
154 
155 	of_entry->dev = &pdev->dev;
156 	of_entry->np = np;
157 	list_add_tail(&of_entry->list, &mfd_of_node_list);
158 
159 	pdev->dev.of_node = np;
160 	pdev->dev.fwnode = &np->fwnode;
161 #endif
162 	return 0;
163 }
164 
165 static int mfd_add_device(struct device *parent, int id,
166 			  const struct mfd_cell *cell,
167 			  struct resource *mem_base,
168 			  int irq_base, struct irq_domain *domain)
169 {
170 	struct resource *res;
171 	struct platform_device *pdev;
172 	struct device_node *np = NULL;
173 	struct mfd_of_node_entry *of_entry, *tmp;
174 	int ret = -ENOMEM;
175 	int platform_id;
176 	int r;
177 
178 	if (id == PLATFORM_DEVID_AUTO)
179 		platform_id = id;
180 	else
181 		platform_id = id + cell->id;
182 
183 	pdev = platform_device_alloc(cell->name, platform_id);
184 	if (!pdev)
185 		goto fail_alloc;
186 
187 	pdev->mfd_cell = kmemdup(cell, sizeof(*cell), GFP_KERNEL);
188 	if (!pdev->mfd_cell)
189 		goto fail_device;
190 
191 	res = kcalloc(cell->num_resources, sizeof(*res), GFP_KERNEL);
192 	if (!res)
193 		goto fail_device;
194 
195 	pdev->dev.parent = parent;
196 	pdev->dev.type = &mfd_dev_type;
197 	pdev->dev.dma_mask = parent->dma_mask;
198 	pdev->dev.dma_parms = parent->dma_parms;
199 	pdev->dev.coherent_dma_mask = parent->coherent_dma_mask;
200 
201 	ret = regulator_bulk_register_supply_alias(
202 			&pdev->dev, cell->parent_supplies,
203 			parent, cell->parent_supplies,
204 			cell->num_parent_supplies);
205 	if (ret < 0)
206 		goto fail_res;
207 
208 	if (IS_ENABLED(CONFIG_OF) && parent->of_node && cell->of_compatible) {
209 		for_each_child_of_node(parent->of_node, np) {
210 			if (of_device_is_compatible(np, cell->of_compatible)) {
211 				/* Ignore 'disabled' devices error free */
212 				if (!of_device_is_available(np)) {
213 					ret = 0;
214 					goto fail_alias;
215 				}
216 
217 				ret = mfd_match_of_node_to_dev(pdev, np, cell);
218 				if (ret == -EAGAIN)
219 					continue;
220 				if (ret)
221 					goto fail_alias;
222 
223 				break;
224 			}
225 		}
226 
227 		if (!pdev->dev.of_node)
228 			pr_warn("%s: Failed to locate of_node [id: %d]\n",
229 				cell->name, platform_id);
230 	}
231 
232 	mfd_acpi_add_device(cell, pdev);
233 
234 	if (cell->pdata_size) {
235 		ret = platform_device_add_data(pdev,
236 					cell->platform_data, cell->pdata_size);
237 		if (ret)
238 			goto fail_of_entry;
239 	}
240 
241 	if (cell->properties) {
242 		ret = platform_device_add_properties(pdev, cell->properties);
243 		if (ret)
244 			goto fail_of_entry;
245 	}
246 
247 	for (r = 0; r < cell->num_resources; r++) {
248 		res[r].name = cell->resources[r].name;
249 		res[r].flags = cell->resources[r].flags;
250 
251 		/* Find out base to use */
252 		if ((cell->resources[r].flags & IORESOURCE_MEM) && mem_base) {
253 			res[r].parent = mem_base;
254 			res[r].start = mem_base->start +
255 				cell->resources[r].start;
256 			res[r].end = mem_base->start +
257 				cell->resources[r].end;
258 		} else if (cell->resources[r].flags & IORESOURCE_IRQ) {
259 			if (domain) {
260 				/* Unable to create mappings for IRQ ranges. */
261 				WARN_ON(cell->resources[r].start !=
262 					cell->resources[r].end);
263 				res[r].start = res[r].end = irq_create_mapping(
264 					domain, cell->resources[r].start);
265 			} else {
266 				res[r].start = irq_base +
267 					cell->resources[r].start;
268 				res[r].end   = irq_base +
269 					cell->resources[r].end;
270 			}
271 		} else {
272 			res[r].parent = cell->resources[r].parent;
273 			res[r].start = cell->resources[r].start;
274 			res[r].end   = cell->resources[r].end;
275 		}
276 
277 		if (!cell->ignore_resource_conflicts) {
278 			if (has_acpi_companion(&pdev->dev)) {
279 				ret = acpi_check_resource_conflict(&res[r]);
280 				if (ret)
281 					goto fail_of_entry;
282 			}
283 		}
284 	}
285 
286 	ret = platform_device_add_resources(pdev, res, cell->num_resources);
287 	if (ret)
288 		goto fail_of_entry;
289 
290 	ret = platform_device_add(pdev);
291 	if (ret)
292 		goto fail_of_entry;
293 
294 	if (cell->pm_runtime_no_callbacks)
295 		pm_runtime_no_callbacks(&pdev->dev);
296 
297 	kfree(res);
298 
299 	return 0;
300 
301 fail_of_entry:
302 	list_for_each_entry_safe(of_entry, tmp, &mfd_of_node_list, list)
303 		if (of_entry->dev == &pdev->dev) {
304 			list_del(&of_entry->list);
305 			kfree(of_entry);
306 		}
307 fail_alias:
308 	regulator_bulk_unregister_supply_alias(&pdev->dev,
309 					       cell->parent_supplies,
310 					       cell->num_parent_supplies);
311 fail_res:
312 	kfree(res);
313 fail_device:
314 	platform_device_put(pdev);
315 fail_alloc:
316 	return ret;
317 }
318 
319 /**
320  * mfd_add_devices - register child devices
321  *
322  * @parent:	Pointer to parent device.
323  * @id:		Can be PLATFORM_DEVID_AUTO to let the Platform API take care
324  *		of device numbering, or will be added to a device's cell_id.
325  * @cells:	Array of (struct mfd_cell)s describing child devices.
326  * @n_devs:	Number of child devices to register.
327  * @mem_base:	Parent register range resource for child devices.
328  * @irq_base:	Base of the range of virtual interrupt numbers allocated for
329  *		this MFD device. Unused if @domain is specified.
330  * @domain:	Interrupt domain to create mappings for hardware interrupts.
331  */
332 int mfd_add_devices(struct device *parent, int id,
333 		    const struct mfd_cell *cells, int n_devs,
334 		    struct resource *mem_base,
335 		    int irq_base, struct irq_domain *domain)
336 {
337 	int i;
338 	int ret;
339 
340 	for (i = 0; i < n_devs; i++) {
341 		ret = mfd_add_device(parent, id, cells + i, mem_base,
342 				     irq_base, domain);
343 		if (ret)
344 			goto fail;
345 	}
346 
347 	return 0;
348 
349 fail:
350 	if (i)
351 		mfd_remove_devices(parent);
352 
353 	return ret;
354 }
355 EXPORT_SYMBOL(mfd_add_devices);
356 
357 static int mfd_remove_devices_fn(struct device *dev, void *data)
358 {
359 	struct platform_device *pdev;
360 	const struct mfd_cell *cell;
361 	int *level = data;
362 
363 	if (dev->type != &mfd_dev_type)
364 		return 0;
365 
366 	pdev = to_platform_device(dev);
367 	cell = mfd_get_cell(pdev);
368 
369 	if (level && cell->level > *level)
370 		return 0;
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_LICENSE("GPL");
444 MODULE_AUTHOR("Ian Molton, Dmitry Baryshkov");
445