xref: /openbmc/linux/drivers/mfd/mfd-core.c (revision 132db935)
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/property.h>
14 #include <linux/mfd/core.h>
15 #include <linux/pm_runtime.h>
16 #include <linux/slab.h>
17 #include <linux/module.h>
18 #include <linux/irqdomain.h>
19 #include <linux/of.h>
20 #include <linux/regulator/consumer.h>
21 
22 static struct device_type mfd_dev_type = {
23 	.name	= "mfd_device",
24 };
25 
26 int mfd_cell_enable(struct platform_device *pdev)
27 {
28 	const struct mfd_cell *cell = mfd_get_cell(pdev);
29 
30 	if (!cell->enable) {
31 		dev_dbg(&pdev->dev, "No .enable() call-back registered\n");
32 		return 0;
33 	}
34 
35 	return cell->enable(pdev);
36 }
37 EXPORT_SYMBOL(mfd_cell_enable);
38 
39 int mfd_cell_disable(struct platform_device *pdev)
40 {
41 	const struct mfd_cell *cell = mfd_get_cell(pdev);
42 
43 	if (!cell->disable) {
44 		dev_dbg(&pdev->dev, "No .disable() call-back registered\n");
45 		return 0;
46 	}
47 
48 	return cell->disable(pdev);
49 }
50 EXPORT_SYMBOL(mfd_cell_disable);
51 
52 #if IS_ENABLED(CONFIG_ACPI)
53 static void mfd_acpi_add_device(const struct mfd_cell *cell,
54 				struct platform_device *pdev)
55 {
56 	const struct mfd_cell_acpi_match *match = cell->acpi_match;
57 	struct acpi_device *parent, *child;
58 	struct acpi_device *adev;
59 
60 	parent = ACPI_COMPANION(pdev->dev.parent);
61 	if (!parent)
62 		return;
63 
64 	/*
65 	 * MFD child device gets its ACPI handle either from the ACPI device
66 	 * directly under the parent that matches the either _HID or _CID, or
67 	 * _ADR or it will use the parent handle if is no ID is given.
68 	 *
69 	 * Note that use of _ADR is a grey area in the ACPI specification,
70 	 * though Intel Galileo Gen2 is using it to distinguish the children
71 	 * devices.
72 	 */
73 	adev = parent;
74 	if (match) {
75 		if (match->pnpid) {
76 			struct acpi_device_id ids[2] = {};
77 
78 			strlcpy(ids[0].id, match->pnpid, sizeof(ids[0].id));
79 			list_for_each_entry(child, &parent->children, node) {
80 				if (!acpi_match_device_ids(child, ids)) {
81 					adev = child;
82 					break;
83 				}
84 			}
85 		} else {
86 			unsigned long long adr;
87 			acpi_status status;
88 
89 			list_for_each_entry(child, &parent->children, node) {
90 				status = acpi_evaluate_integer(child->handle,
91 							       "_ADR", NULL,
92 							       &adr);
93 				if (ACPI_SUCCESS(status) && match->adr == adr) {
94 					adev = child;
95 					break;
96 				}
97 			}
98 		}
99 	}
100 
101 	ACPI_COMPANION_SET(&pdev->dev, adev);
102 }
103 #else
104 static inline void mfd_acpi_add_device(const struct mfd_cell *cell,
105 				       struct platform_device *pdev)
106 {
107 }
108 #endif
109 
110 static int mfd_add_device(struct device *parent, int id,
111 			  const struct mfd_cell *cell,
112 			  struct resource *mem_base,
113 			  int irq_base, struct irq_domain *domain)
114 {
115 	struct resource *res;
116 	struct platform_device *pdev;
117 	struct device_node *np = NULL;
118 	int ret = -ENOMEM;
119 	int platform_id;
120 	int r;
121 
122 	if (id == PLATFORM_DEVID_AUTO)
123 		platform_id = id;
124 	else
125 		platform_id = id + cell->id;
126 
127 	pdev = platform_device_alloc(cell->name, platform_id);
128 	if (!pdev)
129 		goto fail_alloc;
130 
131 	pdev->mfd_cell = kmemdup(cell, sizeof(*cell), GFP_KERNEL);
132 	if (!pdev->mfd_cell)
133 		goto fail_device;
134 
135 	res = kcalloc(cell->num_resources, sizeof(*res), GFP_KERNEL);
136 	if (!res)
137 		goto fail_device;
138 
139 	pdev->dev.parent = parent;
140 	pdev->dev.type = &mfd_dev_type;
141 	pdev->dev.dma_mask = parent->dma_mask;
142 	pdev->dev.dma_parms = parent->dma_parms;
143 	pdev->dev.coherent_dma_mask = parent->coherent_dma_mask;
144 
145 	ret = regulator_bulk_register_supply_alias(
146 			&pdev->dev, cell->parent_supplies,
147 			parent, cell->parent_supplies,
148 			cell->num_parent_supplies);
149 	if (ret < 0)
150 		goto fail_res;
151 
152 	if (parent->of_node && cell->of_compatible) {
153 		for_each_child_of_node(parent->of_node, np) {
154 			if (of_device_is_compatible(np, cell->of_compatible)) {
155 				if (!of_device_is_available(np)) {
156 					/* Ignore disabled devices error free */
157 					ret = 0;
158 					goto fail_alias;
159 				}
160 				pdev->dev.of_node = np;
161 				pdev->dev.fwnode = &np->fwnode;
162 				break;
163 			}
164 		}
165 	}
166 
167 	mfd_acpi_add_device(cell, pdev);
168 
169 	if (cell->pdata_size) {
170 		ret = platform_device_add_data(pdev,
171 					cell->platform_data, cell->pdata_size);
172 		if (ret)
173 			goto fail_alias;
174 	}
175 
176 	if (cell->properties) {
177 		ret = platform_device_add_properties(pdev, cell->properties);
178 		if (ret)
179 			goto fail_alias;
180 	}
181 
182 	for (r = 0; r < cell->num_resources; r++) {
183 		res[r].name = cell->resources[r].name;
184 		res[r].flags = cell->resources[r].flags;
185 
186 		/* Find out base to use */
187 		if ((cell->resources[r].flags & IORESOURCE_MEM) && mem_base) {
188 			res[r].parent = mem_base;
189 			res[r].start = mem_base->start +
190 				cell->resources[r].start;
191 			res[r].end = mem_base->start +
192 				cell->resources[r].end;
193 		} else if (cell->resources[r].flags & IORESOURCE_IRQ) {
194 			if (domain) {
195 				/* Unable to create mappings for IRQ ranges. */
196 				WARN_ON(cell->resources[r].start !=
197 					cell->resources[r].end);
198 				res[r].start = res[r].end = irq_create_mapping(
199 					domain, cell->resources[r].start);
200 			} else {
201 				res[r].start = irq_base +
202 					cell->resources[r].start;
203 				res[r].end   = irq_base +
204 					cell->resources[r].end;
205 			}
206 		} else {
207 			res[r].parent = cell->resources[r].parent;
208 			res[r].start = cell->resources[r].start;
209 			res[r].end   = cell->resources[r].end;
210 		}
211 
212 		if (!cell->ignore_resource_conflicts) {
213 			if (has_acpi_companion(&pdev->dev)) {
214 				ret = acpi_check_resource_conflict(&res[r]);
215 				if (ret)
216 					goto fail_alias;
217 			}
218 		}
219 	}
220 
221 	ret = platform_device_add_resources(pdev, res, cell->num_resources);
222 	if (ret)
223 		goto fail_alias;
224 
225 	ret = platform_device_add(pdev);
226 	if (ret)
227 		goto fail_alias;
228 
229 	if (cell->pm_runtime_no_callbacks)
230 		pm_runtime_no_callbacks(&pdev->dev);
231 
232 	kfree(res);
233 
234 	return 0;
235 
236 fail_alias:
237 	regulator_bulk_unregister_supply_alias(&pdev->dev,
238 					       cell->parent_supplies,
239 					       cell->num_parent_supplies);
240 fail_res:
241 	kfree(res);
242 fail_device:
243 	platform_device_put(pdev);
244 fail_alloc:
245 	return ret;
246 }
247 
248 /**
249  * mfd_add_devices - register child devices
250  *
251  * @parent:	Pointer to parent device.
252  * @id:		Can be PLATFORM_DEVID_AUTO to let the Platform API take care
253  *		of device numbering, or will be added to a device's cell_id.
254  * @cells:	Array of (struct mfd_cell)s describing child devices.
255  * @n_devs:	Number of child devices to register.
256  * @mem_base:	Parent register range resource for child devices.
257  * @irq_base:	Base of the range of virtual interrupt numbers allocated for
258  *		this MFD device. Unused if @domain is specified.
259  * @domain:	Interrupt domain to create mappings for hardware interrupts.
260  */
261 int mfd_add_devices(struct device *parent, int id,
262 		    const struct mfd_cell *cells, int n_devs,
263 		    struct resource *mem_base,
264 		    int irq_base, struct irq_domain *domain)
265 {
266 	int i;
267 	int ret;
268 
269 	for (i = 0; i < n_devs; i++) {
270 		ret = mfd_add_device(parent, id, cells + i, mem_base,
271 				     irq_base, domain);
272 		if (ret)
273 			goto fail;
274 	}
275 
276 	return 0;
277 
278 fail:
279 	if (i)
280 		mfd_remove_devices(parent);
281 
282 	return ret;
283 }
284 EXPORT_SYMBOL(mfd_add_devices);
285 
286 static int mfd_remove_devices_fn(struct device *dev, void *data)
287 {
288 	struct platform_device *pdev;
289 	const struct mfd_cell *cell;
290 
291 	if (dev->type != &mfd_dev_type)
292 		return 0;
293 
294 	pdev = to_platform_device(dev);
295 	cell = mfd_get_cell(pdev);
296 
297 	regulator_bulk_unregister_supply_alias(dev, cell->parent_supplies,
298 					       cell->num_parent_supplies);
299 
300 	platform_device_unregister(pdev);
301 	return 0;
302 }
303 
304 void mfd_remove_devices(struct device *parent)
305 {
306 	device_for_each_child_reverse(parent, NULL, mfd_remove_devices_fn);
307 }
308 EXPORT_SYMBOL(mfd_remove_devices);
309 
310 static void devm_mfd_dev_release(struct device *dev, void *res)
311 {
312 	mfd_remove_devices(dev);
313 }
314 
315 /**
316  * devm_mfd_add_devices - Resource managed version of mfd_add_devices()
317  *
318  * Returns 0 on success or an appropriate negative error number on failure.
319  * All child-devices of the MFD will automatically be removed when it gets
320  * unbinded.
321  */
322 int devm_mfd_add_devices(struct device *dev, int id,
323 			 const struct mfd_cell *cells, int n_devs,
324 			 struct resource *mem_base,
325 			 int irq_base, struct irq_domain *domain)
326 {
327 	struct device **ptr;
328 	int ret;
329 
330 	ptr = devres_alloc(devm_mfd_dev_release, sizeof(*ptr), GFP_KERNEL);
331 	if (!ptr)
332 		return -ENOMEM;
333 
334 	ret = mfd_add_devices(dev, id, cells, n_devs, mem_base,
335 			      irq_base, domain);
336 	if (ret < 0) {
337 		devres_free(ptr);
338 		return ret;
339 	}
340 
341 	*ptr = dev;
342 	devres_add(dev, ptr);
343 
344 	return ret;
345 }
346 EXPORT_SYMBOL(devm_mfd_add_devices);
347 
348 MODULE_LICENSE("GPL");
349 MODULE_AUTHOR("Ian Molton, Dmitry Baryshkov");
350