1/*
2 * drivers/mfd/mfd-core.c
3 *
4 * core MFD support
5 * Copyright (c) 2006 Ian Molton
6 * Copyright (c) 2007,2008 Dmitry Baryshkov
7 *
8 * This program is free software; you can redistribute it and/or modify
9 * it under the terms of the GNU General Public License version 2 as
10 * published by the Free Software Foundation.
11 *
12 */
13
14#include <linux/kernel.h>
15#include <linux/platform_device.h>
16#include <linux/acpi.h>
17#include <linux/property.h>
18#include <linux/mfd/core.h>
19#include <linux/pm_runtime.h>
20#include <linux/slab.h>
21#include <linux/module.h>
22#include <linux/irqdomain.h>
23#include <linux/of.h>
24#include <linux/regulator/consumer.h>
25
26static struct device_type mfd_dev_type = {
27 .name = "mfd_device",
28};
29
30int mfd_cell_enable(struct platform_device *pdev)
31{
32 const struct mfd_cell *cell = mfd_get_cell(pdev);
33 int err = 0;
34
35 /* only call enable hook if the cell wasn't previously enabled */
36 if (atomic_inc_return(cell->usage_count) == 1)
37 err = cell->enable(pdev);
38
39 /* if the enable hook failed, decrement counter to allow retries */
40 if (err)
41 atomic_dec(cell->usage_count);
42
43 return err;
44}
45EXPORT_SYMBOL(mfd_cell_enable);
46
47int mfd_cell_disable(struct platform_device *pdev)
48{
49 const struct mfd_cell *cell = mfd_get_cell(pdev);
50 int err = 0;
51
52 /* only disable if no other clients are using it */
53 if (atomic_dec_return(cell->usage_count) == 0)
54 err = cell->disable(pdev);
55
56 /* if the disable hook failed, increment to allow retries */
57 if (err)
58 atomic_inc(cell->usage_count);
59
60 /* sanity check; did someone call disable too many times? */
61 WARN_ON(atomic_read(cell->usage_count) < 0);
62
63 return err;
64}
65EXPORT_SYMBOL(mfd_cell_disable);
66
67static int mfd_platform_add_cell(struct platform_device *pdev,
68 const struct mfd_cell *cell,
69 atomic_t *usage_count)
70{
71 if (!cell)
72 return 0;
73
74 pdev->mfd_cell = kmemdup(cell, sizeof(*cell), GFP_KERNEL);
75 if (!pdev->mfd_cell)
76 return -ENOMEM;
77
78 pdev->mfd_cell->usage_count = usage_count;
79 return 0;
80}
81
82#if IS_ENABLED(CONFIG_ACPI)
83static void mfd_acpi_add_device(const struct mfd_cell *cell,
84 struct platform_device *pdev)
85{
86 const struct mfd_cell_acpi_match *match = cell->acpi_match;
87 struct acpi_device *parent, *child;
88 struct acpi_device *adev;
89
90 parent = ACPI_COMPANION(pdev->dev.parent);
91 if (!parent)
92 return;
93
94 /*
95 * MFD child device gets its ACPI handle either from the ACPI device
96 * directly under the parent that matches the either _HID or _CID, or
97 * _ADR or it will use the parent handle if is no ID is given.
98 *
99 * Note that use of _ADR is a grey area in the ACPI specification,
100 * though Intel Galileo Gen2 is using it to distinguish the children
101 * devices.
102 */
103 adev = parent;
104 if (match) {
105 if (match->pnpid) {
106 struct acpi_device_id ids[2] = {};
107
108 strlcpy(ids[0].id, match->pnpid, sizeof(ids[0].id));
109 list_for_each_entry(child, &parent->children, node) {
110 if (!acpi_match_device_ids(child, ids)) {
111 adev = child;
112 break;
113 }
114 }
115 } else {
116 unsigned long long adr;
117 acpi_status status;
118
119 list_for_each_entry(child, &parent->children, node) {
120 status = acpi_evaluate_integer(child->handle,
121 "_ADR", NULL,
122 &adr);
123 if (ACPI_SUCCESS(status) && match->adr == adr) {
124 adev = child;
125 break;
126 }
127 }
128 }
129 }
130
131 ACPI_COMPANION_SET(&pdev->dev, adev);
132}
133#else
134static inline void mfd_acpi_add_device(const struct mfd_cell *cell,
135 struct platform_device *pdev)
136{
137}
138#endif
139
140static int mfd_add_device(struct device *parent, int id,
141 const struct mfd_cell *cell, atomic_t *usage_count,
142 struct resource *mem_base,
143 int irq_base, struct irq_domain *domain)
144{
145 struct resource *res;
146 struct platform_device *pdev;
147 struct device_node *np = NULL;
148 int ret = -ENOMEM;
149 int platform_id;
150 int r;
151
152 if (id == PLATFORM_DEVID_AUTO)
153 platform_id = id;
154 else
155 platform_id = id + cell->id;
156
157 pdev = platform_device_alloc(cell->name, platform_id);
158 if (!pdev)
159 goto fail_alloc;
160
161 res = kcalloc(cell->num_resources, sizeof(*res), GFP_KERNEL);
162 if (!res)
163 goto fail_device;
164
165 pdev->dev.parent = parent;
166 pdev->dev.type = &mfd_dev_type;
167 pdev->dev.dma_mask = parent->dma_mask;
168 pdev->dev.dma_parms = parent->dma_parms;
169 pdev->dev.coherent_dma_mask = parent->coherent_dma_mask;
170
171 ret = regulator_bulk_register_supply_alias(
172 &pdev->dev, cell->parent_supplies,
173 parent, cell->parent_supplies,
174 cell->num_parent_supplies);
175 if (ret < 0)
176 goto fail_res;
177
178 if (parent->of_node && cell->of_compatible) {
179 for_each_child_of_node(parent->of_node, np) {
180 if (of_device_is_compatible(np, cell->of_compatible)) {
181 pdev->dev.of_node = np;
182 break;
183 }
184 }
185 }
186
187 mfd_acpi_add_device(cell, pdev);
188
189 if (cell->pdata_size) {
190 ret = platform_device_add_data(pdev,
191 cell->platform_data, cell->pdata_size);
192 if (ret)
193 goto fail_alias;
194 }
195
196 if (cell->properties) {
197 ret = platform_device_add_properties(pdev, cell->properties);
198 if (ret)
199 goto fail_alias;
200 }
201
202 ret = mfd_platform_add_cell(pdev, cell, usage_count);
203 if (ret)
204 goto fail_alias;
205
206 for (r = 0; r < cell->num_resources; r++) {
207 res[r].name = cell->resources[r].name;
208 res[r].flags = cell->resources[r].flags;
209
210 /* Find out base to use */
211 if ((cell->resources[r].flags & IORESOURCE_MEM) && mem_base) {
212 res[r].parent = mem_base;
213 res[r].start = mem_base->start +
214 cell->resources[r].start;
215 res[r].end = mem_base->start +
216 cell->resources[r].end;
217 } else if (cell->resources[r].flags & IORESOURCE_IRQ) {
218 if (domain) {
219 /* Unable to create mappings for IRQ ranges. */
220 WARN_ON(cell->resources[r].start !=
221 cell->resources[r].end);
222 res[r].start = res[r].end = irq_create_mapping(
223 domain, cell->resources[r].start);
224 } else {
225 res[r].start = irq_base +
226 cell->resources[r].start;
227 res[r].end = irq_base +
228 cell->resources[r].end;
229 }
230 } else {
231 res[r].parent = cell->resources[r].parent;
232 res[r].start = cell->resources[r].start;
233 res[r].end = cell->resources[r].end;
234 }
235
236 if (!cell->ignore_resource_conflicts) {
237 if (has_acpi_companion(&pdev->dev)) {
238 ret = acpi_check_resource_conflict(&res[r]);
239 if (ret)
240 goto fail_alias;
241 }
242 }
243 }
244
245 ret = platform_device_add_resources(pdev, res, cell->num_resources);
246 if (ret)
247 goto fail_alias;
248
249 ret = platform_device_add(pdev);
250 if (ret)
251 goto fail_alias;
252
253 if (cell->pm_runtime_no_callbacks)
254 pm_runtime_no_callbacks(&pdev->dev);
255
256 kfree(res);
257
258 return 0;
259
260fail_alias:
261 regulator_bulk_unregister_supply_alias(&pdev->dev,
262 cell->parent_supplies,
263 cell->num_parent_supplies);
264fail_res:
265 kfree(res);
266fail_device:
267 platform_device_put(pdev);
268fail_alloc:
269 return ret;
270}
271
272int mfd_add_devices(struct device *parent, int id,
273 const struct mfd_cell *cells, int n_devs,
274 struct resource *mem_base,
275 int irq_base, struct irq_domain *domain)
276{
277 int i;
278 int ret;
279 atomic_t *cnts;
280
281 /* initialize reference counting for all cells */
282 cnts = kcalloc(n_devs, sizeof(*cnts), GFP_KERNEL);
283 if (!cnts)
284 return -ENOMEM;
285
286 for (i = 0; i < n_devs; i++) {
287 atomic_set(&cnts[i], 0);
288 ret = mfd_add_device(parent, id, cells + i, cnts + i, mem_base,
289 irq_base, domain);
290 if (ret)
291 goto fail;
292 }
293
294 return 0;
295
296fail:
297 if (i)
298 mfd_remove_devices(parent);
299 else
300 kfree(cnts);
301 return ret;
302}
303EXPORT_SYMBOL(mfd_add_devices);
304
305static int mfd_remove_devices_fn(struct device *dev, void *c)
306{
307 struct platform_device *pdev;
308 const struct mfd_cell *cell;
309 atomic_t **usage_count = c;
310
311 if (dev->type != &mfd_dev_type)
312 return 0;
313
314 pdev = to_platform_device(dev);
315 cell = mfd_get_cell(pdev);
316
317 regulator_bulk_unregister_supply_alias(dev, cell->parent_supplies,
318 cell->num_parent_supplies);
319
320 /* find the base address of usage_count pointers (for freeing) */
321 if (!*usage_count || (cell->usage_count < *usage_count))
322 *usage_count = cell->usage_count;
323
324 platform_device_unregister(pdev);
325 return 0;
326}
327
328void mfd_remove_devices(struct device *parent)
329{
330 atomic_t *cnts = NULL;
331
332 device_for_each_child_reverse(parent, &cnts, mfd_remove_devices_fn);
333 kfree(cnts);
334}
335EXPORT_SYMBOL(mfd_remove_devices);
336
337static void devm_mfd_dev_release(struct device *dev, void *res)
338{
339 mfd_remove_devices(dev);
340}
341
342/**
343 * devm_mfd_add_devices - Resource managed version of mfd_add_devices()
344 *
345 * Returns 0 on success or an appropriate negative error number on failure.
346 * All child-devices of the MFD will automatically be removed when it gets
347 * unbinded.
348 */
349int devm_mfd_add_devices(struct device *dev, int id,
350 const struct mfd_cell *cells, int n_devs,
351 struct resource *mem_base,
352 int irq_base, struct irq_domain *domain)
353{
354 struct device **ptr;
355 int ret;
356
357 ptr = devres_alloc(devm_mfd_dev_release, sizeof(*ptr), GFP_KERNEL);
358 if (!ptr)
359 return -ENOMEM;
360
361 ret = mfd_add_devices(dev, id, cells, n_devs, mem_base,
362 irq_base, domain);
363 if (ret < 0) {
364 devres_free(ptr);
365 return ret;
366 }
367
368 *ptr = dev;
369 devres_add(dev, ptr);
370
371 return ret;
372}
373EXPORT_SYMBOL(devm_mfd_add_devices);
374
375int mfd_clone_cell(const char *cell, const char **clones, size_t n_clones)
376{
377 struct mfd_cell cell_entry;
378 struct device *dev;
379 struct platform_device *pdev;
380 int i;
381
382 /* fetch the parent cell's device (should already be registered!) */
383 dev = bus_find_device_by_name(&platform_bus_type, NULL, cell);
384 if (!dev) {
385 printk(KERN_ERR "failed to find device for cell %s\n", cell);
386 return -ENODEV;
387 }
388 pdev = to_platform_device(dev);
389 memcpy(&cell_entry, mfd_get_cell(pdev), sizeof(cell_entry));
390
391 WARN_ON(!cell_entry.enable);
392
393 for (i = 0; i < n_clones; i++) {
394 cell_entry.name = clones[i];
395 /* don't give up if a single call fails; just report error */
396 if (mfd_add_device(pdev->dev.parent, -1, &cell_entry,
397 cell_entry.usage_count, NULL, 0, NULL))
398 dev_err(dev, "failed to create platform device '%s'\n",
399 clones[i]);
400 }
401
402 put_device(dev);
403
404 return 0;
405}
406EXPORT_SYMBOL(mfd_clone_cell);
407
408MODULE_LICENSE("GPL");
409MODULE_AUTHOR("Ian Molton, Dmitry Baryshkov");
410