xref: /openbmc/linux/drivers/mfd/mfd-core.c (revision babbdf5b)
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 = NULL;
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 at least Intel Galileo Gen 2 is using it to distinguish
81 	 * the children devices.
82 	 */
83 	if (match) {
84 		if (match->pnpid) {
85 			struct acpi_device_id ids[2] = {};
86 
87 			strlcpy(ids[0].id, match->pnpid, sizeof(ids[0].id));
88 			list_for_each_entry(child, &parent->children, node) {
89 				if (!acpi_match_device_ids(child, ids)) {
90 					adev = child;
91 					break;
92 				}
93 			}
94 		} else {
95 			adev = acpi_find_child_device(parent, match->adr, false);
96 		}
97 	}
98 
99 	ACPI_COMPANION_SET(&pdev->dev, adev ?: parent);
100 }
101 #else
102 static inline void mfd_acpi_add_device(const struct mfd_cell *cell,
103 				       struct platform_device *pdev)
104 {
105 }
106 #endif
107 
108 static int mfd_match_of_node_to_dev(struct platform_device *pdev,
109 				    struct device_node *np,
110 				    const struct mfd_cell *cell)
111 {
112 #if IS_ENABLED(CONFIG_OF)
113 	struct mfd_of_node_entry *of_entry;
114 	const __be32 *reg;
115 	u64 of_node_addr;
116 
117 	/* Skip if OF node has previously been allocated to a device */
118 	list_for_each_entry(of_entry, &mfd_of_node_list, list)
119 		if (of_entry->np == np)
120 			return -EAGAIN;
121 
122 	if (!cell->use_of_reg)
123 		/* No of_reg defined - allocate first free compatible match */
124 		goto allocate_of_node;
125 
126 	/* We only care about each node's first defined address */
127 	reg = of_get_address(np, 0, NULL, NULL);
128 	if (!reg)
129 		/* OF node does not contatin a 'reg' property to match to */
130 		return -EAGAIN;
131 
132 	of_node_addr = of_read_number(reg, of_n_addr_cells(np));
133 
134 	if (cell->of_reg != of_node_addr)
135 		/* No match */
136 		return -EAGAIN;
137 
138 allocate_of_node:
139 	of_entry = kzalloc(sizeof(*of_entry), GFP_KERNEL);
140 	if (!of_entry)
141 		return -ENOMEM;
142 
143 	of_entry->dev = &pdev->dev;
144 	of_entry->np = np;
145 	list_add_tail(&of_entry->list, &mfd_of_node_list);
146 
147 	pdev->dev.of_node = np;
148 	pdev->dev.fwnode = &np->fwnode;
149 #endif
150 	return 0;
151 }
152 
153 static int mfd_add_device(struct device *parent, int id,
154 			  const struct mfd_cell *cell,
155 			  struct resource *mem_base,
156 			  int irq_base, struct irq_domain *domain)
157 {
158 	struct resource *res;
159 	struct platform_device *pdev;
160 	struct device_node *np = NULL;
161 	struct mfd_of_node_entry *of_entry, *tmp;
162 	int ret = -ENOMEM;
163 	int platform_id;
164 	int r;
165 
166 	if (id == PLATFORM_DEVID_AUTO)
167 		platform_id = id;
168 	else
169 		platform_id = id + cell->id;
170 
171 	pdev = platform_device_alloc(cell->name, platform_id);
172 	if (!pdev)
173 		goto fail_alloc;
174 
175 	pdev->mfd_cell = kmemdup(cell, sizeof(*cell), GFP_KERNEL);
176 	if (!pdev->mfd_cell)
177 		goto fail_device;
178 
179 	res = kcalloc(cell->num_resources, sizeof(*res), GFP_KERNEL);
180 	if (!res)
181 		goto fail_device;
182 
183 	pdev->dev.parent = parent;
184 	pdev->dev.type = &mfd_dev_type;
185 	pdev->dev.dma_mask = parent->dma_mask;
186 	pdev->dev.dma_parms = parent->dma_parms;
187 	pdev->dev.coherent_dma_mask = parent->coherent_dma_mask;
188 
189 	ret = regulator_bulk_register_supply_alias(
190 			&pdev->dev, cell->parent_supplies,
191 			parent, cell->parent_supplies,
192 			cell->num_parent_supplies);
193 	if (ret < 0)
194 		goto fail_res;
195 
196 	if (IS_ENABLED(CONFIG_OF) && parent->of_node && cell->of_compatible) {
197 		for_each_child_of_node(parent->of_node, np) {
198 			if (of_device_is_compatible(np, cell->of_compatible)) {
199 				/* Ignore 'disabled' devices error free */
200 				if (!of_device_is_available(np)) {
201 					ret = 0;
202 					goto fail_alias;
203 				}
204 
205 				ret = mfd_match_of_node_to_dev(pdev, np, cell);
206 				if (ret == -EAGAIN)
207 					continue;
208 				if (ret)
209 					goto fail_alias;
210 
211 				break;
212 			}
213 		}
214 
215 		if (!pdev->dev.of_node)
216 			pr_warn("%s: Failed to locate of_node [id: %d]\n",
217 				cell->name, platform_id);
218 	}
219 
220 	mfd_acpi_add_device(cell, pdev);
221 
222 	if (cell->pdata_size) {
223 		ret = platform_device_add_data(pdev,
224 					cell->platform_data, cell->pdata_size);
225 		if (ret)
226 			goto fail_of_entry;
227 	}
228 
229 	if (cell->swnode) {
230 		ret = device_add_software_node(&pdev->dev, cell->swnode);
231 		if (ret)
232 			goto fail_of_entry;
233 	}
234 
235 	for (r = 0; r < cell->num_resources; r++) {
236 		res[r].name = cell->resources[r].name;
237 		res[r].flags = cell->resources[r].flags;
238 
239 		/* Find out base to use */
240 		if ((cell->resources[r].flags & IORESOURCE_MEM) && mem_base) {
241 			res[r].parent = mem_base;
242 			res[r].start = mem_base->start +
243 				cell->resources[r].start;
244 			res[r].end = mem_base->start +
245 				cell->resources[r].end;
246 		} else if (cell->resources[r].flags & IORESOURCE_IRQ) {
247 			if (domain) {
248 				/* Unable to create mappings for IRQ ranges. */
249 				WARN_ON(cell->resources[r].start !=
250 					cell->resources[r].end);
251 				res[r].start = res[r].end = irq_create_mapping(
252 					domain, cell->resources[r].start);
253 			} else {
254 				res[r].start = irq_base +
255 					cell->resources[r].start;
256 				res[r].end   = irq_base +
257 					cell->resources[r].end;
258 			}
259 		} else {
260 			res[r].parent = cell->resources[r].parent;
261 			res[r].start = cell->resources[r].start;
262 			res[r].end   = cell->resources[r].end;
263 		}
264 
265 		if (!cell->ignore_resource_conflicts) {
266 			if (has_acpi_companion(&pdev->dev)) {
267 				ret = acpi_check_resource_conflict(&res[r]);
268 				if (ret)
269 					goto fail_of_entry;
270 			}
271 		}
272 	}
273 
274 	ret = platform_device_add_resources(pdev, res, cell->num_resources);
275 	if (ret)
276 		goto fail_of_entry;
277 
278 	ret = platform_device_add(pdev);
279 	if (ret)
280 		goto fail_of_entry;
281 
282 	if (cell->pm_runtime_no_callbacks)
283 		pm_runtime_no_callbacks(&pdev->dev);
284 
285 	kfree(res);
286 
287 	return 0;
288 
289 fail_of_entry:
290 	list_for_each_entry_safe(of_entry, tmp, &mfd_of_node_list, list)
291 		if (of_entry->dev == &pdev->dev) {
292 			list_del(&of_entry->list);
293 			kfree(of_entry);
294 		}
295 	device_remove_software_node(&pdev->dev);
296 fail_alias:
297 	regulator_bulk_unregister_supply_alias(&pdev->dev,
298 					       cell->parent_supplies,
299 					       cell->num_parent_supplies);
300 fail_res:
301 	kfree(res);
302 fail_device:
303 	platform_device_put(pdev);
304 fail_alloc:
305 	return ret;
306 }
307 
308 /**
309  * mfd_add_devices - register child devices
310  *
311  * @parent:	Pointer to parent device.
312  * @id:		Can be PLATFORM_DEVID_AUTO to let the Platform API take care
313  *		of device numbering, or will be added to a device's cell_id.
314  * @cells:	Array of (struct mfd_cell)s describing child devices.
315  * @n_devs:	Number of child devices to register.
316  * @mem_base:	Parent register range resource for child devices.
317  * @irq_base:	Base of the range of virtual interrupt numbers allocated for
318  *		this MFD device. Unused if @domain is specified.
319  * @domain:	Interrupt domain to create mappings for hardware interrupts.
320  */
321 int mfd_add_devices(struct device *parent, int id,
322 		    const struct mfd_cell *cells, int n_devs,
323 		    struct resource *mem_base,
324 		    int irq_base, struct irq_domain *domain)
325 {
326 	int i;
327 	int ret;
328 
329 	for (i = 0; i < n_devs; i++) {
330 		ret = mfd_add_device(parent, id, cells + i, mem_base,
331 				     irq_base, domain);
332 		if (ret)
333 			goto fail;
334 	}
335 
336 	return 0;
337 
338 fail:
339 	if (i)
340 		mfd_remove_devices(parent);
341 
342 	return ret;
343 }
344 EXPORT_SYMBOL(mfd_add_devices);
345 
346 static int mfd_remove_devices_fn(struct device *dev, void *data)
347 {
348 	struct platform_device *pdev;
349 	const struct mfd_cell *cell;
350 	int *level = data;
351 
352 	if (dev->type != &mfd_dev_type)
353 		return 0;
354 
355 	pdev = to_platform_device(dev);
356 	cell = mfd_get_cell(pdev);
357 
358 	if (level && cell->level > *level)
359 		return 0;
360 
361 	regulator_bulk_unregister_supply_alias(dev, cell->parent_supplies,
362 					       cell->num_parent_supplies);
363 
364 	device_remove_software_node(&pdev->dev);
365 
366 	platform_device_unregister(pdev);
367 	return 0;
368 }
369 
370 void mfd_remove_devices_late(struct device *parent)
371 {
372 	int level = MFD_DEP_LEVEL_HIGH;
373 
374 	device_for_each_child_reverse(parent, &level, mfd_remove_devices_fn);
375 }
376 EXPORT_SYMBOL(mfd_remove_devices_late);
377 
378 void mfd_remove_devices(struct device *parent)
379 {
380 	int level = MFD_DEP_LEVEL_NORMAL;
381 
382 	device_for_each_child_reverse(parent, &level, mfd_remove_devices_fn);
383 }
384 EXPORT_SYMBOL(mfd_remove_devices);
385 
386 static void devm_mfd_dev_release(struct device *dev, void *res)
387 {
388 	mfd_remove_devices(dev);
389 }
390 
391 /**
392  * devm_mfd_add_devices - Resource managed version of mfd_add_devices()
393  *
394  * Returns 0 on success or an appropriate negative error number on failure.
395  * All child-devices of the MFD will automatically be removed when it gets
396  * unbinded.
397  *
398  * @dev:	Pointer to parent device.
399  * @id:		Can be PLATFORM_DEVID_AUTO to let the Platform API take care
400  *		of device numbering, or will be added to a device's cell_id.
401  * @cells:	Array of (struct mfd_cell)s describing child devices.
402  * @n_devs:	Number of child devices to register.
403  * @mem_base:	Parent register range resource for child devices.
404  * @irq_base:	Base of the range of virtual interrupt numbers allocated for
405  *		this MFD device. Unused if @domain is specified.
406  * @domain:	Interrupt domain to create mappings for hardware interrupts.
407  */
408 int devm_mfd_add_devices(struct device *dev, int id,
409 			 const struct mfd_cell *cells, int n_devs,
410 			 struct resource *mem_base,
411 			 int irq_base, struct irq_domain *domain)
412 {
413 	struct device **ptr;
414 	int ret;
415 
416 	ptr = devres_alloc(devm_mfd_dev_release, sizeof(*ptr), GFP_KERNEL);
417 	if (!ptr)
418 		return -ENOMEM;
419 
420 	ret = mfd_add_devices(dev, id, cells, n_devs, mem_base,
421 			      irq_base, domain);
422 	if (ret < 0) {
423 		devres_free(ptr);
424 		return ret;
425 	}
426 
427 	*ptr = dev;
428 	devres_add(dev, ptr);
429 
430 	return ret;
431 }
432 EXPORT_SYMBOL(devm_mfd_add_devices);
433 
434 MODULE_LICENSE("GPL");
435 MODULE_AUTHOR("Ian Molton, Dmitry Baryshkov");
436