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 static DEFINE_MUTEX(mfd_of_node_mutex);
26
27 struct mfd_of_node_entry {
28 struct list_head list;
29 struct device *dev;
30 struct device_node *np;
31 };
32
33 static const struct device_type mfd_dev_type = {
34 .name = "mfd_device",
35 };
36
37 #if IS_ENABLED(CONFIG_ACPI)
38 struct match_ids_walk_data {
39 struct acpi_device_id *ids;
40 struct acpi_device *adev;
41 };
42
match_device_ids(struct acpi_device * adev,void * data)43 static int match_device_ids(struct acpi_device *adev, void *data)
44 {
45 struct match_ids_walk_data *wd = data;
46
47 if (!acpi_match_device_ids(adev, wd->ids)) {
48 wd->adev = adev;
49 return 1;
50 }
51
52 return 0;
53 }
54
mfd_acpi_add_device(const struct mfd_cell * cell,struct platform_device * pdev)55 static void mfd_acpi_add_device(const struct mfd_cell *cell,
56 struct platform_device *pdev)
57 {
58 const struct mfd_cell_acpi_match *match = cell->acpi_match;
59 struct acpi_device *adev = NULL;
60 struct acpi_device *parent;
61
62 parent = ACPI_COMPANION(pdev->dev.parent);
63 if (!parent)
64 return;
65
66 /*
67 * MFD child device gets its ACPI handle either from the ACPI device
68 * directly under the parent that matches the either _HID or _CID, or
69 * _ADR or it will use the parent handle if is no ID is given.
70 *
71 * Note that use of _ADR is a grey area in the ACPI specification,
72 * though at least Intel Galileo Gen 2 is using it to distinguish
73 * the children devices.
74 */
75 if (match) {
76 if (match->pnpid) {
77 struct acpi_device_id ids[2] = {};
78 struct match_ids_walk_data wd = {
79 .adev = NULL,
80 .ids = ids,
81 };
82
83 strscpy(ids[0].id, match->pnpid, sizeof(ids[0].id));
84 acpi_dev_for_each_child(parent, match_device_ids, &wd);
85 adev = wd.adev;
86 } else {
87 adev = acpi_find_child_device(parent, match->adr, false);
88 }
89 }
90
91 /*
92 * NOTE: The fwnode design doesn't allow proper stacking/sharing. This
93 * should eventually turn into a device fwnode API call that will allow
94 * prepending to a list of fwnodes (with ACPI taking precedence).
95 *
96 * set_primary_fwnode() is used here, instead of device_set_node(), as
97 * device_set_node() will overwrite the existing fwnode, which may be an
98 * OF node that was populated earlier. To support a use case where ACPI
99 * and OF is used in conjunction, we call set_primary_fwnode() instead.
100 */
101 set_primary_fwnode(&pdev->dev, acpi_fwnode_handle(adev ?: parent));
102 }
103 #else
mfd_acpi_add_device(const struct mfd_cell * cell,struct platform_device * pdev)104 static inline void mfd_acpi_add_device(const struct mfd_cell *cell,
105 struct platform_device *pdev)
106 {
107 }
108 #endif
109
mfd_match_of_node_to_dev(struct platform_device * pdev,struct device_node * np,const struct mfd_cell * cell)110 static int mfd_match_of_node_to_dev(struct platform_device *pdev,
111 struct device_node *np,
112 const struct mfd_cell *cell)
113 {
114 struct mfd_of_node_entry *of_entry;
115 u64 of_node_addr;
116
117 /* Skip if OF node has previously been allocated to a device */
118 scoped_guard(mutex, &mfd_of_node_mutex) {
119 list_for_each_entry(of_entry, &mfd_of_node_list, list)
120 if (of_entry->np == np)
121 return -EAGAIN;
122 }
123
124 if (!cell->use_of_reg)
125 /* No of_reg defined - allocate first free compatible match */
126 goto allocate_of_node;
127
128 /* We only care about each node's first defined address */
129 if (of_property_read_reg(np, 0, &of_node_addr, NULL))
130 /* OF node does not contatin a 'reg' property to match to */
131 return -EAGAIN;
132
133 if (cell->of_reg != of_node_addr)
134 /* No match */
135 return -EAGAIN;
136
137 allocate_of_node:
138 of_entry = kzalloc_obj(*of_entry);
139 if (!of_entry)
140 return -ENOMEM;
141
142 of_entry->dev = &pdev->dev;
143 of_entry->np = of_node_get(np);
144 scoped_guard(mutex, &mfd_of_node_mutex)
145 list_add_tail(&of_entry->list, &mfd_of_node_list);
146
147 device_set_node(&pdev->dev, of_fwnode_handle(np));
148 return 0;
149 }
150
mfd_add_device(struct device * parent,int id,const struct mfd_cell * cell,struct resource * mem_base,int irq_base,struct irq_domain * domain)151 static int mfd_add_device(struct device *parent, int id,
152 const struct mfd_cell *cell,
153 struct resource *mem_base,
154 int irq_base, struct irq_domain *domain)
155 {
156 struct resource *res;
157 struct platform_device *pdev;
158 struct mfd_of_node_entry *of_entry, *tmp;
159 bool disabled = false;
160 int ret = -ENOMEM;
161 int platform_id;
162 int r;
163
164 if (id == PLATFORM_DEVID_AUTO)
165 platform_id = id;
166 else
167 platform_id = id + cell->id;
168
169 pdev = platform_device_alloc(cell->name, platform_id);
170 if (!pdev)
171 goto fail_alloc;
172
173 pdev->mfd_cell = kmemdup(cell, sizeof(*cell), GFP_KERNEL);
174 if (!pdev->mfd_cell)
175 goto fail_device;
176
177 res = kzalloc_objs(*res, cell->num_resources);
178 if (!res)
179 goto fail_device;
180
181 pdev->dev.parent = parent;
182 pdev->dev.type = &mfd_dev_type;
183 pdev->dev.dma_mask = parent->dma_mask;
184 pdev->dev.dma_parms = parent->dma_parms;
185 pdev->dev.coherent_dma_mask = parent->coherent_dma_mask;
186
187 ret = regulator_bulk_register_supply_alias(
188 &pdev->dev, cell->parent_supplies,
189 parent, cell->parent_supplies,
190 cell->num_parent_supplies);
191 if (ret < 0)
192 goto fail_res;
193
194 if (IS_ENABLED(CONFIG_OF) && parent->of_node && cell->of_compatible) {
195 for_each_child_of_node_scoped(parent->of_node, np) {
196 if (of_device_is_compatible(np, cell->of_compatible)) {
197 /* Skip 'disabled' devices */
198 if (!of_device_is_available(np)) {
199 disabled = true;
200 continue;
201 }
202
203 ret = mfd_match_of_node_to_dev(pdev, np, cell);
204 if (ret == -EAGAIN)
205 continue;
206 if (ret)
207 goto fail_alias;
208
209 goto match;
210 }
211 }
212
213 if (disabled) {
214 /* Ignore 'disabled' devices error free */
215 ret = 0;
216 goto fail_alias;
217 }
218
219 match:
220 if (!pdev->dev.of_node)
221 pr_warn("%s: Failed to locate of_node [id: %d]\n",
222 cell->name, platform_id);
223 }
224
225 mfd_acpi_add_device(cell, pdev);
226
227 if (cell->pdata_size) {
228 ret = platform_device_add_data(pdev,
229 cell->platform_data, cell->pdata_size);
230 if (ret)
231 goto fail_of_entry;
232 }
233
234 if (cell->swnode) {
235 ret = device_add_software_node(&pdev->dev, cell->swnode);
236 if (ret)
237 goto fail_of_entry;
238 }
239
240 for (r = 0; r < cell->num_resources; r++) {
241 res[r].name = cell->resources[r].name;
242 res[r].flags = cell->resources[r].flags;
243
244 /* Find out base to use */
245 if ((cell->resources[r].flags & IORESOURCE_MEM) && mem_base) {
246 res[r].parent = mem_base;
247 res[r].start = mem_base->start +
248 cell->resources[r].start;
249 res[r].end = mem_base->start +
250 cell->resources[r].end;
251 } else if (cell->resources[r].flags & IORESOURCE_IRQ) {
252 if (domain) {
253 /* Unable to create mappings for IRQ ranges. */
254 WARN_ON(cell->resources[r].start !=
255 cell->resources[r].end);
256 res[r].start = res[r].end = irq_create_mapping(
257 domain, cell->resources[r].start);
258 } else {
259 res[r].start = irq_base +
260 cell->resources[r].start;
261 res[r].end = irq_base +
262 cell->resources[r].end;
263 }
264 } else {
265 res[r].parent = cell->resources[r].parent;
266 res[r].start = cell->resources[r].start;
267 res[r].end = cell->resources[r].end;
268 }
269
270 if (!cell->ignore_resource_conflicts) {
271 if (has_acpi_companion(&pdev->dev)) {
272 ret = acpi_check_resource_conflict(&res[r]);
273 if (ret)
274 goto fail_res_conflict;
275 }
276 }
277 }
278
279 ret = platform_device_add_resources(pdev, res, cell->num_resources);
280 if (ret)
281 goto fail_res_conflict;
282
283 ret = platform_device_add(pdev);
284 if (ret)
285 goto fail_res_conflict;
286
287 if (cell->pm_runtime_no_callbacks)
288 pm_runtime_no_callbacks(&pdev->dev);
289
290 kfree(res);
291
292 return 0;
293
294 fail_res_conflict:
295 if (cell->swnode)
296 device_remove_software_node(&pdev->dev);
297 fail_of_entry:
298 scoped_guard(mutex, &mfd_of_node_mutex) {
299 list_for_each_entry_safe(of_entry, tmp, &mfd_of_node_list, list)
300 if (of_entry->dev == &pdev->dev) {
301 list_del(&of_entry->list);
302 kfree(of_entry);
303 }
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 */
mfd_add_devices(struct device * parent,int id,const struct mfd_cell * cells,int n_devs,struct resource * mem_base,int irq_base,struct irq_domain * domain)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
mfd_remove_devices_fn(struct device * dev,void * data)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 struct mfd_of_node_entry *of_entry, *tmp;
360 int *level = data;
361
362 if (dev->type != &mfd_dev_type)
363 return 0;
364
365 pdev = to_platform_device(dev);
366 cell = mfd_get_cell(pdev);
367
368 if (level && cell->level > *level)
369 return 0;
370
371 if (cell->swnode)
372 device_remove_software_node(&pdev->dev);
373
374 scoped_guard(mutex, &mfd_of_node_mutex) {
375 list_for_each_entry_safe(of_entry, tmp, &mfd_of_node_list, list)
376 if (of_entry->dev == &pdev->dev) {
377 list_del(&of_entry->list);
378 kfree(of_entry);
379 }
380 }
381
382 regulator_bulk_unregister_supply_alias(dev, cell->parent_supplies,
383 cell->num_parent_supplies);
384
385 platform_device_unregister(pdev);
386 return 0;
387 }
388
mfd_remove_devices_late(struct device * parent)389 void mfd_remove_devices_late(struct device *parent)
390 {
391 int level = MFD_DEP_LEVEL_HIGH;
392
393 device_for_each_child_reverse(parent, &level, mfd_remove_devices_fn);
394 }
395 EXPORT_SYMBOL(mfd_remove_devices_late);
396
mfd_remove_devices(struct device * parent)397 void mfd_remove_devices(struct device *parent)
398 {
399 int level = MFD_DEP_LEVEL_NORMAL;
400
401 device_for_each_child_reverse(parent, &level, mfd_remove_devices_fn);
402 }
403 EXPORT_SYMBOL(mfd_remove_devices);
404
devm_mfd_dev_release(struct device * dev,void * res)405 static void devm_mfd_dev_release(struct device *dev, void *res)
406 {
407 mfd_remove_devices(dev);
408 }
409
410 /**
411 * devm_mfd_add_devices - Resource managed version of mfd_add_devices()
412 *
413 * Returns 0 on success or an appropriate negative error number on failure.
414 * All child-devices of the MFD will automatically be removed when it gets
415 * unbinded.
416 *
417 * @dev: Pointer to parent device.
418 * @id: Can be PLATFORM_DEVID_AUTO to let the Platform API take care
419 * of device numbering, or will be added to a device's cell_id.
420 * @cells: Array of (struct mfd_cell)s describing child devices.
421 * @n_devs: Number of child devices to register.
422 * @mem_base: Parent register range resource for child devices.
423 * @irq_base: Base of the range of virtual interrupt numbers allocated for
424 * this MFD device. Unused if @domain is specified.
425 * @domain: Interrupt domain to create mappings for hardware interrupts.
426 */
devm_mfd_add_devices(struct device * dev,int id,const struct mfd_cell * cells,int n_devs,struct resource * mem_base,int irq_base,struct irq_domain * domain)427 int devm_mfd_add_devices(struct device *dev, int id,
428 const struct mfd_cell *cells, int n_devs,
429 struct resource *mem_base,
430 int irq_base, struct irq_domain *domain)
431 {
432 struct device **ptr;
433 int ret;
434
435 ptr = devres_alloc(devm_mfd_dev_release, sizeof(*ptr), GFP_KERNEL);
436 if (!ptr)
437 return -ENOMEM;
438
439 ret = mfd_add_devices(dev, id, cells, n_devs, mem_base,
440 irq_base, domain);
441 if (ret < 0) {
442 devres_free(ptr);
443 return ret;
444 }
445
446 *ptr = dev;
447 devres_add(dev, ptr);
448
449 return ret;
450 }
451 EXPORT_SYMBOL(devm_mfd_add_devices);
452
453 MODULE_DESCRIPTION("Core MFD support");
454 MODULE_LICENSE("GPL");
455 MODULE_AUTHOR("Ian Molton, Dmitry Baryshkov");
456