[go: nahoru, domu]
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#include <linux/module.h>
21#include <linux/irqdomain.h>
22#include <linux/of.h>
23#include <linux/regulator/consumer.h>
24
25static struct device_type mfd_dev_type = {
26	.name	= "mfd_device",
27};
28
29int mfd_cell_enable(struct platform_device *pdev)
30{
31	const struct mfd_cell *cell = mfd_get_cell(pdev);
32	int err = 0;
33
34	/* only call enable hook if the cell wasn't previously enabled */
35	if (atomic_inc_return(cell->usage_count) == 1)
36		err = cell->enable(pdev);
37
38	/* if the enable hook failed, decrement counter to allow retries */
39	if (err)
40		atomic_dec(cell->usage_count);
41
42	return err;
43}
44EXPORT_SYMBOL(mfd_cell_enable);
45
46int mfd_cell_disable(struct platform_device *pdev)
47{
48	const struct mfd_cell *cell = mfd_get_cell(pdev);
49	int err = 0;
50
51	/* only disable if no other clients are using it */
52	if (atomic_dec_return(cell->usage_count) == 0)
53		err = cell->disable(pdev);
54
55	/* if the disable hook failed, increment to allow retries */
56	if (err)
57		atomic_inc(cell->usage_count);
58
59	/* sanity check; did someone call disable too many times? */
60	WARN_ON(atomic_read(cell->usage_count) < 0);
61
62	return err;
63}
64EXPORT_SYMBOL(mfd_cell_disable);
65
66static int mfd_platform_add_cell(struct platform_device *pdev,
67				 const struct mfd_cell *cell,
68				 atomic_t *usage_count)
69{
70	if (!cell)
71		return 0;
72
73	pdev->mfd_cell = kmemdup(cell, sizeof(*cell), GFP_KERNEL);
74	if (!pdev->mfd_cell)
75		return -ENOMEM;
76
77	pdev->mfd_cell->usage_count = usage_count;
78	return 0;
79}
80
81#if IS_ENABLED(CONFIG_ACPI)
82static void mfd_acpi_add_device(const struct mfd_cell *cell,
83				struct platform_device *pdev)
84{
85	struct acpi_device *parent_adev;
86	struct acpi_device *adev;
87
88	parent_adev = ACPI_COMPANION(pdev->dev.parent);
89	if (!parent_adev)
90		return;
91
92	/*
93	 * MFD child device gets its ACPI handle either from the ACPI
94	 * device directly under the parent that matches the acpi_pnpid or
95	 * it will use the parent handle if is no acpi_pnpid is given.
96	 */
97	adev = parent_adev;
98	if (cell->acpi_pnpid) {
99		struct acpi_device_id ids[2] = {};
100		struct acpi_device *child_adev;
101
102		strlcpy(ids[0].id, cell->acpi_pnpid, sizeof(ids[0].id));
103		list_for_each_entry(child_adev, &parent_adev->children, node)
104			if (acpi_match_device_ids(child_adev, ids)) {
105				adev = child_adev;
106				break;
107			}
108	}
109
110	ACPI_COMPANION_SET(&pdev->dev, adev);
111}
112#else
113static inline void mfd_acpi_add_device(const struct mfd_cell *cell,
114				       struct platform_device *pdev)
115{
116}
117#endif
118
119static int mfd_add_device(struct device *parent, int id,
120			  const struct mfd_cell *cell, atomic_t *usage_count,
121			  struct resource *mem_base,
122			  int irq_base, struct irq_domain *domain)
123{
124	struct resource *res;
125	struct platform_device *pdev;
126	struct device_node *np = NULL;
127	int ret = -ENOMEM;
128	int r;
129
130	pdev = platform_device_alloc(cell->name, id + cell->id);
131	if (!pdev)
132		goto fail_alloc;
133
134	res = kzalloc(sizeof(*res) * cell->num_resources, GFP_KERNEL);
135	if (!res)
136		goto fail_device;
137
138	pdev->dev.parent = parent;
139	pdev->dev.type = &mfd_dev_type;
140	pdev->dev.dma_mask = parent->dma_mask;
141	pdev->dev.dma_parms = parent->dma_parms;
142	pdev->dev.coherent_dma_mask = parent->coherent_dma_mask;
143
144	ret = regulator_bulk_register_supply_alias(
145			&pdev->dev, cell->parent_supplies,
146			parent, cell->parent_supplies,
147			cell->num_parent_supplies);
148	if (ret < 0)
149		goto fail_res;
150
151	if (parent->of_node && cell->of_compatible) {
152		for_each_child_of_node(parent->of_node, np) {
153			if (of_device_is_compatible(np, cell->of_compatible)) {
154				pdev->dev.of_node = np;
155				break;
156			}
157		}
158	}
159
160	mfd_acpi_add_device(cell, pdev);
161
162	if (cell->pdata_size) {
163		ret = platform_device_add_data(pdev,
164					cell->platform_data, cell->pdata_size);
165		if (ret)
166			goto fail_alias;
167	}
168
169	ret = mfd_platform_add_cell(pdev, cell, usage_count);
170	if (ret)
171		goto fail_alias;
172
173	for (r = 0; r < cell->num_resources; r++) {
174		res[r].name = cell->resources[r].name;
175		res[r].flags = cell->resources[r].flags;
176
177		/* Find out base to use */
178		if ((cell->resources[r].flags & IORESOURCE_MEM) && mem_base) {
179			res[r].parent = mem_base;
180			res[r].start = mem_base->start +
181				cell->resources[r].start;
182			res[r].end = mem_base->start +
183				cell->resources[r].end;
184		} else if (cell->resources[r].flags & IORESOURCE_IRQ) {
185			if (domain) {
186				/* Unable to create mappings for IRQ ranges. */
187				WARN_ON(cell->resources[r].start !=
188					cell->resources[r].end);
189				res[r].start = res[r].end = irq_create_mapping(
190					domain, cell->resources[r].start);
191			} else {
192				res[r].start = irq_base +
193					cell->resources[r].start;
194				res[r].end   = irq_base +
195					cell->resources[r].end;
196			}
197		} else {
198			res[r].parent = cell->resources[r].parent;
199			res[r].start = cell->resources[r].start;
200			res[r].end   = cell->resources[r].end;
201		}
202
203		if (!cell->ignore_resource_conflicts) {
204			ret = acpi_check_resource_conflict(&res[r]);
205			if (ret)
206				goto fail_alias;
207		}
208	}
209
210	ret = platform_device_add_resources(pdev, res, cell->num_resources);
211	if (ret)
212		goto fail_alias;
213
214	ret = platform_device_add(pdev);
215	if (ret)
216		goto fail_alias;
217
218	if (cell->pm_runtime_no_callbacks)
219		pm_runtime_no_callbacks(&pdev->dev);
220
221	kfree(res);
222
223	return 0;
224
225fail_alias:
226	regulator_bulk_unregister_supply_alias(&pdev->dev,
227					       cell->parent_supplies,
228					       cell->num_parent_supplies);
229fail_res:
230	kfree(res);
231fail_device:
232	platform_device_put(pdev);
233fail_alloc:
234	return ret;
235}
236
237int mfd_add_devices(struct device *parent, int id,
238		    const struct mfd_cell *cells, int n_devs,
239		    struct resource *mem_base,
240		    int irq_base, struct irq_domain *domain)
241{
242	int i;
243	int ret;
244	atomic_t *cnts;
245
246	/* initialize reference counting for all cells */
247	cnts = kcalloc(n_devs, sizeof(*cnts), GFP_KERNEL);
248	if (!cnts)
249		return -ENOMEM;
250
251	for (i = 0; i < n_devs; i++) {
252		atomic_set(&cnts[i], 0);
253		ret = mfd_add_device(parent, id, cells + i, cnts + i, mem_base,
254				     irq_base, domain);
255		if (ret)
256			goto fail;
257	}
258
259	return 0;
260
261fail:
262	if (i)
263		mfd_remove_devices(parent);
264	else
265		kfree(cnts);
266	return ret;
267}
268EXPORT_SYMBOL(mfd_add_devices);
269
270static int mfd_remove_devices_fn(struct device *dev, void *c)
271{
272	struct platform_device *pdev;
273	const struct mfd_cell *cell;
274	atomic_t **usage_count = c;
275
276	if (dev->type != &mfd_dev_type)
277		return 0;
278
279	pdev = to_platform_device(dev);
280	cell = mfd_get_cell(pdev);
281
282	regulator_bulk_unregister_supply_alias(dev, cell->parent_supplies,
283					       cell->num_parent_supplies);
284
285	/* find the base address of usage_count pointers (for freeing) */
286	if (!*usage_count || (cell->usage_count < *usage_count))
287		*usage_count = cell->usage_count;
288
289	platform_device_unregister(pdev);
290	return 0;
291}
292
293void mfd_remove_devices(struct device *parent)
294{
295	atomic_t *cnts = NULL;
296
297	device_for_each_child(parent, &cnts, mfd_remove_devices_fn);
298	kfree(cnts);
299}
300EXPORT_SYMBOL(mfd_remove_devices);
301
302int mfd_clone_cell(const char *cell, const char **clones, size_t n_clones)
303{
304	struct mfd_cell cell_entry;
305	struct device *dev;
306	struct platform_device *pdev;
307	int i;
308
309	/* fetch the parent cell's device (should already be registered!) */
310	dev = bus_find_device_by_name(&platform_bus_type, NULL, cell);
311	if (!dev) {
312		printk(KERN_ERR "failed to find device for cell %s\n", cell);
313		return -ENODEV;
314	}
315	pdev = to_platform_device(dev);
316	memcpy(&cell_entry, mfd_get_cell(pdev), sizeof(cell_entry));
317
318	WARN_ON(!cell_entry.enable);
319
320	for (i = 0; i < n_clones; i++) {
321		cell_entry.name = clones[i];
322		/* don't give up if a single call fails; just report error */
323		if (mfd_add_device(pdev->dev.parent, -1, &cell_entry,
324				   cell_entry.usage_count, NULL, 0, NULL))
325			dev_err(dev, "failed to create platform device '%s'\n",
326					clones[i]);
327	}
328
329	return 0;
330}
331EXPORT_SYMBOL(mfd_clone_cell);
332
333MODULE_LICENSE("GPL");
334MODULE_AUTHOR("Ian Molton, Dmitry Baryshkov");
335