xref: /openbmc/linux/drivers/mfd/mfd-core.c (revision b285d2ae)
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 devices 'disabled' by Device Tree */
130 	if (!of_device_is_available(np))
131 		return -ENODEV;
132 
133 	/* Skip if OF node has previously been allocated to a device */
134 	list_for_each_entry(of_entry, &mfd_of_node_list, list)
135 		if (of_entry->np == np)
136 			return -EAGAIN;
137 
138 	if (!cell->use_of_reg)
139 		/* No of_reg defined - allocate first free compatible match */
140 		goto allocate_of_node;
141 
142 	/* We only care about each node's first defined address */
143 	reg = of_get_address(np, 0, NULL, NULL);
144 	if (!reg)
145 		/* OF node does not contatin a 'reg' property to match to */
146 		return -EAGAIN;
147 
148 	of_node_addr = of_read_number(reg, of_n_addr_cells(np));
149 
150 	if (cell->of_reg != of_node_addr)
151 		/* No match */
152 		return -EAGAIN;
153 
154 allocate_of_node:
155 	of_entry = kzalloc(sizeof(*of_entry), GFP_KERNEL);
156 	if (!of_entry)
157 		return -ENOMEM;
158 
159 	of_entry->dev = &pdev->dev;
160 	of_entry->np = np;
161 	list_add_tail(&of_entry->list, &mfd_of_node_list);
162 
163 	pdev->dev.of_node = np;
164 	pdev->dev.fwnode = &np->fwnode;
165 #endif
166 	return 0;
167 }
168 
169 static int mfd_add_device(struct device *parent, int id,
170 			  const struct mfd_cell *cell,
171 			  struct resource *mem_base,
172 			  int irq_base, struct irq_domain *domain)
173 {
174 	struct resource *res;
175 	struct platform_device *pdev;
176 	struct device_node *np = NULL;
177 	struct mfd_of_node_entry *of_entry, *tmp;
178 	int ret = -ENOMEM;
179 	int platform_id;
180 	int r;
181 
182 	if (id == PLATFORM_DEVID_AUTO)
183 		platform_id = id;
184 	else
185 		platform_id = id + cell->id;
186 
187 	pdev = platform_device_alloc(cell->name, platform_id);
188 	if (!pdev)
189 		goto fail_alloc;
190 
191 	pdev->mfd_cell = kmemdup(cell, sizeof(*cell), GFP_KERNEL);
192 	if (!pdev->mfd_cell)
193 		goto fail_device;
194 
195 	res = kcalloc(cell->num_resources, sizeof(*res), GFP_KERNEL);
196 	if (!res)
197 		goto fail_device;
198 
199 	pdev->dev.parent = parent;
200 	pdev->dev.type = &mfd_dev_type;
201 	pdev->dev.dma_mask = parent->dma_mask;
202 	pdev->dev.dma_parms = parent->dma_parms;
203 	pdev->dev.coherent_dma_mask = parent->coherent_dma_mask;
204 
205 	ret = regulator_bulk_register_supply_alias(
206 			&pdev->dev, cell->parent_supplies,
207 			parent, cell->parent_supplies,
208 			cell->num_parent_supplies);
209 	if (ret < 0)
210 		goto fail_res;
211 
212 	if (IS_ENABLED(CONFIG_OF) && parent->of_node && cell->of_compatible) {
213 		for_each_child_of_node(parent->of_node, np) {
214 			if (of_device_is_compatible(np, cell->of_compatible)) {
215 				ret = mfd_match_of_node_to_dev(pdev, np, cell);
216 				if (ret == -EAGAIN)
217 					continue;
218 				if (ret)
219 					goto fail_alias;
220 
221 				break;
222 			}
223 		}
224 
225 		if (!pdev->dev.of_node)
226 			pr_warn("%s: Failed to locate of_node [id: %d]\n",
227 				cell->name, platform_id);
228 	}
229 
230 	mfd_acpi_add_device(cell, pdev);
231 
232 	if (cell->pdata_size) {
233 		ret = platform_device_add_data(pdev,
234 					cell->platform_data, cell->pdata_size);
235 		if (ret)
236 			goto fail_of_entry;
237 	}
238 
239 	if (cell->properties) {
240 		ret = platform_device_add_properties(pdev, cell->properties);
241 		if (ret)
242 			goto fail_of_entry;
243 	}
244 
245 	for (r = 0; r < cell->num_resources; r++) {
246 		res[r].name = cell->resources[r].name;
247 		res[r].flags = cell->resources[r].flags;
248 
249 		/* Find out base to use */
250 		if ((cell->resources[r].flags & IORESOURCE_MEM) && mem_base) {
251 			res[r].parent = mem_base;
252 			res[r].start = mem_base->start +
253 				cell->resources[r].start;
254 			res[r].end = mem_base->start +
255 				cell->resources[r].end;
256 		} else if (cell->resources[r].flags & IORESOURCE_IRQ) {
257 			if (domain) {
258 				/* Unable to create mappings for IRQ ranges. */
259 				WARN_ON(cell->resources[r].start !=
260 					cell->resources[r].end);
261 				res[r].start = res[r].end = irq_create_mapping(
262 					domain, cell->resources[r].start);
263 			} else {
264 				res[r].start = irq_base +
265 					cell->resources[r].start;
266 				res[r].end   = irq_base +
267 					cell->resources[r].end;
268 			}
269 		} else {
270 			res[r].parent = cell->resources[r].parent;
271 			res[r].start = cell->resources[r].start;
272 			res[r].end   = cell->resources[r].end;
273 		}
274 
275 		if (!cell->ignore_resource_conflicts) {
276 			if (has_acpi_companion(&pdev->dev)) {
277 				ret = acpi_check_resource_conflict(&res[r]);
278 				if (ret)
279 					goto fail_of_entry;
280 			}
281 		}
282 	}
283 
284 	ret = platform_device_add_resources(pdev, res, cell->num_resources);
285 	if (ret)
286 		goto fail_of_entry;
287 
288 	ret = platform_device_add(pdev);
289 	if (ret)
290 		goto fail_of_entry;
291 
292 	if (cell->pm_runtime_no_callbacks)
293 		pm_runtime_no_callbacks(&pdev->dev);
294 
295 	kfree(res);
296 
297 	return 0;
298 
299 fail_of_entry:
300 	list_for_each_entry_safe(of_entry, tmp, &mfd_of_node_list, list)
301 		if (of_entry->dev == &pdev->dev) {
302 			list_del(&of_entry->list);
303 			kfree(of_entry);
304 		}
305 fail_alias:
306 	regulator_bulk_unregister_supply_alias(&pdev->dev,
307 					       cell->parent_supplies,
308 					       cell->num_parent_supplies);
309 fail_res:
310 	kfree(res);
311 fail_device:
312 	platform_device_put(pdev);
313 fail_alloc:
314 	return ret;
315 }
316 
317 /**
318  * mfd_add_devices - register child devices
319  *
320  * @parent:	Pointer to parent device.
321  * @id:		Can be PLATFORM_DEVID_AUTO to let the Platform API take care
322  *		of device numbering, or will be added to a device's cell_id.
323  * @cells:	Array of (struct mfd_cell)s describing child devices.
324  * @n_devs:	Number of child devices to register.
325  * @mem_base:	Parent register range resource for child devices.
326  * @irq_base:	Base of the range of virtual interrupt numbers allocated for
327  *		this MFD device. Unused if @domain is specified.
328  * @domain:	Interrupt domain to create mappings for hardware interrupts.
329  */
330 int mfd_add_devices(struct device *parent, int id,
331 		    const struct mfd_cell *cells, int n_devs,
332 		    struct resource *mem_base,
333 		    int irq_base, struct irq_domain *domain)
334 {
335 	int i;
336 	int ret;
337 
338 	for (i = 0; i < n_devs; i++) {
339 		ret = mfd_add_device(parent, id, cells + i, mem_base,
340 				     irq_base, domain);
341 		if (ret)
342 			goto fail;
343 	}
344 
345 	return 0;
346 
347 fail:
348 	if (i)
349 		mfd_remove_devices(parent);
350 
351 	return ret;
352 }
353 EXPORT_SYMBOL(mfd_add_devices);
354 
355 static int mfd_remove_devices_fn(struct device *dev, void *data)
356 {
357 	struct platform_device *pdev;
358 	const struct mfd_cell *cell;
359 	int *level = data;
360 
361 	if (dev->type != &mfd_dev_type)
362 		return 0;
363 
364 	pdev = to_platform_device(dev);
365 	cell = mfd_get_cell(pdev);
366 
367 	if (level && cell->level > *level)
368 		return 0;
369 
370 	regulator_bulk_unregister_supply_alias(dev, cell->parent_supplies,
371 					       cell->num_parent_supplies);
372 
373 	kfree(cell);
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