Commit | Line | Data |
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87d68730 DA |
1 | /* |
2 | * System Control Driver | |
3 | * | |
4 | * Copyright (C) 2012 Freescale Semiconductor, Inc. | |
5 | * Copyright (C) 2012 Linaro Ltd. | |
6 | * | |
7 | * Author: Dong Aisheng <dong.aisheng@linaro.org> | |
8 | * | |
9 | * This program is free software; you can redistribute it and/or modify | |
10 | * it under the terms of the GNU General Public License as published by | |
11 | * the Free Software Foundation; either version 2 of the License, or | |
12 | * (at your option) any later version. | |
13 | */ | |
14 | ||
15 | #include <linux/err.h> | |
16 | #include <linux/io.h> | |
17 | #include <linux/module.h> | |
bdb0066d | 18 | #include <linux/list.h> |
87d68730 DA |
19 | #include <linux/of.h> |
20 | #include <linux/of_address.h> | |
21 | #include <linux/of_platform.h> | |
29f9b6cf | 22 | #include <linux/platform_data/syscon.h> |
87d68730 DA |
23 | #include <linux/platform_device.h> |
24 | #include <linux/regmap.h> | |
75177dee | 25 | #include <linux/mfd/syscon.h> |
bdb0066d | 26 | #include <linux/slab.h> |
87d68730 DA |
27 | |
28 | static struct platform_driver syscon_driver; | |
29 | ||
bdb0066d PD |
30 | static DEFINE_SPINLOCK(syscon_list_slock); |
31 | static LIST_HEAD(syscon_list); | |
32 | ||
87d68730 | 33 | struct syscon { |
bdb0066d | 34 | struct device_node *np; |
87d68730 | 35 | struct regmap *regmap; |
bdb0066d PD |
36 | struct list_head list; |
37 | }; | |
38 | ||
39 | static struct regmap_config syscon_regmap_config = { | |
40 | .reg_bits = 32, | |
41 | .val_bits = 32, | |
42 | .reg_stride = 4, | |
87d68730 DA |
43 | }; |
44 | ||
bdb0066d | 45 | static struct syscon *of_syscon_register(struct device_node *np) |
87d68730 | 46 | { |
bdb0066d PD |
47 | struct syscon *syscon; |
48 | struct regmap *regmap; | |
49 | void __iomem *base; | |
50 | int ret; | |
51 | struct regmap_config syscon_config = syscon_regmap_config; | |
52 | ||
53 | if (!of_device_is_compatible(np, "syscon")) | |
54 | return ERR_PTR(-EINVAL); | |
55 | ||
56 | syscon = kzalloc(sizeof(*syscon), GFP_KERNEL); | |
57 | if (!syscon) | |
58 | return ERR_PTR(-ENOMEM); | |
59 | ||
60 | base = of_iomap(np, 0); | |
61 | if (!base) { | |
62 | ret = -ENOMEM; | |
63 | goto err_map; | |
64 | } | |
65 | ||
66 | /* Parse the device's DT node for an endianness specification */ | |
67 | if (of_property_read_bool(np, "big-endian")) | |
68 | syscon_config.val_format_endian = REGMAP_ENDIAN_BIG; | |
69 | else if (of_property_read_bool(np, "little-endian")) | |
70 | syscon_config.val_format_endian = REGMAP_ENDIAN_LITTLE; | |
71 | ||
72 | regmap = regmap_init_mmio(NULL, base, &syscon_config); | |
73 | if (IS_ERR(regmap)) { | |
74 | pr_err("regmap init failed\n"); | |
75 | ret = PTR_ERR(regmap); | |
76 | goto err_regmap; | |
77 | } | |
78 | ||
79 | syscon->regmap = regmap; | |
80 | syscon->np = np; | |
81 | ||
82 | spin_lock(&syscon_list_slock); | |
83 | list_add_tail(&syscon->list, &syscon_list); | |
84 | spin_unlock(&syscon_list_slock); | |
87d68730 | 85 | |
bdb0066d PD |
86 | return syscon; |
87 | ||
88 | err_regmap: | |
89 | iounmap(base); | |
90 | err_map: | |
91 | kfree(syscon); | |
92 | return ERR_PTR(ret); | |
87d68730 DA |
93 | } |
94 | ||
95 | struct regmap *syscon_node_to_regmap(struct device_node *np) | |
96 | { | |
bdb0066d | 97 | struct syscon *entry, *syscon = NULL; |
87d68730 | 98 | |
bdb0066d | 99 | spin_lock(&syscon_list_slock); |
87d68730 | 100 | |
bdb0066d PD |
101 | list_for_each_entry(entry, &syscon_list, list) |
102 | if (entry->np == np) { | |
103 | syscon = entry; | |
104 | break; | |
105 | } | |
106 | ||
107 | spin_unlock(&syscon_list_slock); | |
108 | ||
109 | if (!syscon) | |
110 | syscon = of_syscon_register(np); | |
111 | ||
112 | if (IS_ERR(syscon)) | |
113 | return ERR_CAST(syscon); | |
87d68730 DA |
114 | |
115 | return syscon->regmap; | |
116 | } | |
117 | EXPORT_SYMBOL_GPL(syscon_node_to_regmap); | |
118 | ||
119 | struct regmap *syscon_regmap_lookup_by_compatible(const char *s) | |
120 | { | |
121 | struct device_node *syscon_np; | |
122 | struct regmap *regmap; | |
123 | ||
124 | syscon_np = of_find_compatible_node(NULL, NULL, s); | |
125 | if (!syscon_np) | |
126 | return ERR_PTR(-ENODEV); | |
127 | ||
128 | regmap = syscon_node_to_regmap(syscon_np); | |
129 | of_node_put(syscon_np); | |
130 | ||
131 | return regmap; | |
132 | } | |
133 | EXPORT_SYMBOL_GPL(syscon_regmap_lookup_by_compatible); | |
134 | ||
5ab3a89a AS |
135 | static int syscon_match_pdevname(struct device *dev, void *data) |
136 | { | |
5ab3a89a AS |
137 | return !strcmp(dev_name(dev), (const char *)data); |
138 | } | |
139 | ||
140 | struct regmap *syscon_regmap_lookup_by_pdevname(const char *s) | |
141 | { | |
142 | struct device *dev; | |
143 | struct syscon *syscon; | |
144 | ||
145 | dev = driver_find_device(&syscon_driver.driver, NULL, (void *)s, | |
146 | syscon_match_pdevname); | |
147 | if (!dev) | |
148 | return ERR_PTR(-EPROBE_DEFER); | |
149 | ||
150 | syscon = dev_get_drvdata(dev); | |
151 | ||
152 | return syscon->regmap; | |
153 | } | |
154 | EXPORT_SYMBOL_GPL(syscon_regmap_lookup_by_pdevname); | |
155 | ||
87d68730 DA |
156 | struct regmap *syscon_regmap_lookup_by_phandle(struct device_node *np, |
157 | const char *property) | |
158 | { | |
159 | struct device_node *syscon_np; | |
160 | struct regmap *regmap; | |
161 | ||
45330bb4 PD |
162 | if (property) |
163 | syscon_np = of_parse_phandle(np, property, 0); | |
164 | else | |
165 | syscon_np = np; | |
166 | ||
87d68730 DA |
167 | if (!syscon_np) |
168 | return ERR_PTR(-ENODEV); | |
169 | ||
170 | regmap = syscon_node_to_regmap(syscon_np); | |
171 | of_node_put(syscon_np); | |
172 | ||
173 | return regmap; | |
174 | } | |
175 | EXPORT_SYMBOL_GPL(syscon_regmap_lookup_by_phandle); | |
176 | ||
f791be49 | 177 | static int syscon_probe(struct platform_device *pdev) |
87d68730 DA |
178 | { |
179 | struct device *dev = &pdev->dev; | |
29f9b6cf | 180 | struct syscon_platform_data *pdata = dev_get_platdata(dev); |
87d68730 | 181 | struct syscon *syscon; |
5ab3a89a | 182 | struct resource *res; |
f10111cc | 183 | void __iomem *base; |
87d68730 | 184 | |
5ab3a89a | 185 | syscon = devm_kzalloc(dev, sizeof(*syscon), GFP_KERNEL); |
87d68730 DA |
186 | if (!syscon) |
187 | return -ENOMEM; | |
188 | ||
5ab3a89a AS |
189 | res = platform_get_resource(pdev, IORESOURCE_MEM, 0); |
190 | if (!res) | |
191 | return -ENOENT; | |
87d68730 | 192 | |
f10111cc AS |
193 | base = devm_ioremap(dev, res->start, resource_size(res)); |
194 | if (!base) | |
5ab3a89a | 195 | return -ENOMEM; |
87d68730 | 196 | |
5ab3a89a | 197 | syscon_regmap_config.max_register = res->end - res->start - 3; |
29f9b6cf PM |
198 | if (pdata) |
199 | syscon_regmap_config.name = pdata->label; | |
f10111cc | 200 | syscon->regmap = devm_regmap_init_mmio(dev, base, |
87d68730 DA |
201 | &syscon_regmap_config); |
202 | if (IS_ERR(syscon->regmap)) { | |
203 | dev_err(dev, "regmap init failed\n"); | |
204 | return PTR_ERR(syscon->regmap); | |
205 | } | |
206 | ||
87d68730 DA |
207 | platform_set_drvdata(pdev, syscon); |
208 | ||
38d8974e | 209 | dev_dbg(dev, "regmap %pR registered\n", res); |
87d68730 DA |
210 | |
211 | return 0; | |
212 | } | |
213 | ||
5ab3a89a AS |
214 | static const struct platform_device_id syscon_ids[] = { |
215 | { "syscon", }, | |
216 | { } | |
217 | }; | |
87d68730 DA |
218 | |
219 | static struct platform_driver syscon_driver = { | |
220 | .driver = { | |
221 | .name = "syscon", | |
87d68730 DA |
222 | }, |
223 | .probe = syscon_probe, | |
5ab3a89a | 224 | .id_table = syscon_ids, |
87d68730 DA |
225 | }; |
226 | ||
227 | static int __init syscon_init(void) | |
228 | { | |
229 | return platform_driver_register(&syscon_driver); | |
230 | } | |
231 | postcore_initcall(syscon_init); | |
232 | ||
233 | static void __exit syscon_exit(void) | |
234 | { | |
235 | platform_driver_unregister(&syscon_driver); | |
236 | } | |
237 | module_exit(syscon_exit); | |
238 | ||
239 | MODULE_AUTHOR("Dong Aisheng <dong.aisheng@linaro.org>"); | |
240 | MODULE_DESCRIPTION("System Control driver"); | |
241 | MODULE_LICENSE("GPL v2"); |