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v3.1
  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/mfd/core.h>
 18#include <linux/pm_runtime.h>
 19#include <linux/slab.h>
 
 
 
 
 
 
 
 
 20
 21int mfd_cell_enable(struct platform_device *pdev)
 22{
 23	const struct mfd_cell *cell = mfd_get_cell(pdev);
 24	int err = 0;
 25
 26	/* only call enable hook if the cell wasn't previously enabled */
 27	if (atomic_inc_return(cell->usage_count) == 1)
 28		err = cell->enable(pdev);
 29
 30	/* if the enable hook failed, decrement counter to allow retries */
 31	if (err)
 32		atomic_dec(cell->usage_count);
 33
 34	return err;
 35}
 36EXPORT_SYMBOL(mfd_cell_enable);
 37
 38int mfd_cell_disable(struct platform_device *pdev)
 39{
 40	const struct mfd_cell *cell = mfd_get_cell(pdev);
 41	int err = 0;
 42
 43	/* only disable if no other clients are using it */
 44	if (atomic_dec_return(cell->usage_count) == 0)
 45		err = cell->disable(pdev);
 46
 47	/* if the disable hook failed, increment to allow retries */
 48	if (err)
 49		atomic_inc(cell->usage_count);
 50
 51	/* sanity check; did someone call disable too many times? */
 52	WARN_ON(atomic_read(cell->usage_count) < 0);
 53
 54	return err;
 55}
 56EXPORT_SYMBOL(mfd_cell_disable);
 57
 58static int mfd_platform_add_cell(struct platform_device *pdev,
 59				 const struct mfd_cell *cell)
 
 60{
 61	if (!cell)
 62		return 0;
 63
 64	pdev->mfd_cell = kmemdup(cell, sizeof(*cell), GFP_KERNEL);
 65	if (!pdev->mfd_cell)
 66		return -ENOMEM;
 67
 
 68	return 0;
 69}
 70
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 71static int mfd_add_device(struct device *parent, int id,
 72			  const struct mfd_cell *cell,
 73			  struct resource *mem_base,
 74			  int irq_base)
 75{
 76	struct resource *res;
 77	struct platform_device *pdev;
 
 78	int ret = -ENOMEM;
 
 79	int r;
 80
 81	pdev = platform_device_alloc(cell->name, id + cell->id);
 
 
 
 
 
 82	if (!pdev)
 83		goto fail_alloc;
 84
 85	res = kzalloc(sizeof(*res) * cell->num_resources, GFP_KERNEL);
 86	if (!res)
 87		goto fail_device;
 88
 89	pdev->dev.parent = parent;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 90
 91	if (cell->pdata_size) {
 92		ret = platform_device_add_data(pdev,
 93					cell->platform_data, cell->pdata_size);
 94		if (ret)
 95			goto fail_res;
 
 
 
 
 
 
 96	}
 97
 98	ret = mfd_platform_add_cell(pdev, cell);
 99	if (ret)
100		goto fail_res;
101
102	for (r = 0; r < cell->num_resources; r++) {
103		res[r].name = cell->resources[r].name;
104		res[r].flags = cell->resources[r].flags;
105
106		/* Find out base to use */
107		if ((cell->resources[r].flags & IORESOURCE_MEM) && mem_base) {
108			res[r].parent = mem_base;
109			res[r].start = mem_base->start +
110				cell->resources[r].start;
111			res[r].end = mem_base->start +
112				cell->resources[r].end;
113		} else if (cell->resources[r].flags & IORESOURCE_IRQ) {
114			res[r].start = irq_base +
115				cell->resources[r].start;
116			res[r].end   = irq_base +
117				cell->resources[r].end;
 
 
 
 
 
 
 
 
118		} else {
119			res[r].parent = cell->resources[r].parent;
120			res[r].start = cell->resources[r].start;
121			res[r].end   = cell->resources[r].end;
122		}
123
124		if (!cell->ignore_resource_conflicts) {
125			ret = acpi_check_resource_conflict(res);
126			if (ret)
127				goto fail_res;
 
 
128		}
129	}
130
131	ret = platform_device_add_resources(pdev, res, cell->num_resources);
132	if (ret)
133		goto fail_res;
134
135	ret = platform_device_add(pdev);
136	if (ret)
137		goto fail_res;
138
139	if (cell->pm_runtime_no_callbacks)
140		pm_runtime_no_callbacks(&pdev->dev);
141
142	kfree(res);
143
144	return 0;
145
 
 
 
 
146fail_res:
147	kfree(res);
148fail_device:
149	platform_device_put(pdev);
150fail_alloc:
151	return ret;
152}
153
154int mfd_add_devices(struct device *parent, int id,
155		    struct mfd_cell *cells, int n_devs,
156		    struct resource *mem_base,
157		    int irq_base)
158{
159	int i;
160	int ret = 0;
161	atomic_t *cnts;
162
163	/* initialize reference counting for all cells */
164	cnts = kcalloc(sizeof(*cnts), n_devs, GFP_KERNEL);
165	if (!cnts)
166		return -ENOMEM;
167
168	for (i = 0; i < n_devs; i++) {
169		atomic_set(&cnts[i], 0);
170		cells[i].usage_count = &cnts[i];
171		ret = mfd_add_device(parent, id, cells + i, mem_base, irq_base);
172		if (ret)
173			break;
174	}
175
176	if (ret)
177		mfd_remove_devices(parent);
178
 
 
 
 
 
179	return ret;
180}
181EXPORT_SYMBOL(mfd_add_devices);
182
183static int mfd_remove_devices_fn(struct device *dev, void *c)
184{
185	struct platform_device *pdev = to_platform_device(dev);
186	const struct mfd_cell *cell = mfd_get_cell(pdev);
187	atomic_t **usage_count = c;
188
 
 
 
 
 
 
 
 
 
189	/* find the base address of usage_count pointers (for freeing) */
190	if (!*usage_count || (cell->usage_count < *usage_count))
191		*usage_count = cell->usage_count;
192
193	platform_device_unregister(pdev);
194	return 0;
195}
196
197void mfd_remove_devices(struct device *parent)
198{
199	atomic_t *cnts = NULL;
200
201	device_for_each_child(parent, &cnts, mfd_remove_devices_fn);
202	kfree(cnts);
203}
204EXPORT_SYMBOL(mfd_remove_devices);
205
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
206int mfd_clone_cell(const char *cell, const char **clones, size_t n_clones)
207{
208	struct mfd_cell cell_entry;
209	struct device *dev;
210	struct platform_device *pdev;
211	int i;
212
213	/* fetch the parent cell's device (should already be registered!) */
214	dev = bus_find_device_by_name(&platform_bus_type, NULL, cell);
215	if (!dev) {
216		printk(KERN_ERR "failed to find device for cell %s\n", cell);
217		return -ENODEV;
218	}
219	pdev = to_platform_device(dev);
220	memcpy(&cell_entry, mfd_get_cell(pdev), sizeof(cell_entry));
221
222	WARN_ON(!cell_entry.enable);
223
224	for (i = 0; i < n_clones; i++) {
225		cell_entry.name = clones[i];
226		/* don't give up if a single call fails; just report error */
227		if (mfd_add_device(pdev->dev.parent, -1, &cell_entry, NULL, 0))
 
228			dev_err(dev, "failed to create platform device '%s'\n",
229					clones[i]);
230	}
 
 
231
232	return 0;
233}
234EXPORT_SYMBOL(mfd_clone_cell);
235
236MODULE_LICENSE("GPL");
237MODULE_AUTHOR("Ian Molton, Dmitry Baryshkov");
v4.10.11
  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 = kzalloc(sizeof(*res) * cell->num_resources, 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");