]>
Commit | Line | Data |
---|---|---|
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 | ||
c131045d | 39 | static const struct regmap_config syscon_regmap_config = { |
bdb0066d PD |
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; | |
db2fb60c | 50 | u32 reg_io_width; |
bdb0066d PD |
51 | int ret; |
52 | struct regmap_config syscon_config = syscon_regmap_config; | |
ca668f0e | 53 | struct resource res; |
bdb0066d PD |
54 | |
55 | if (!of_device_is_compatible(np, "syscon")) | |
56 | return ERR_PTR(-EINVAL); | |
57 | ||
58 | syscon = kzalloc(sizeof(*syscon), GFP_KERNEL); | |
59 | if (!syscon) | |
60 | return ERR_PTR(-ENOMEM); | |
61 | ||
ca668f0e PZ |
62 | if (of_address_to_resource(np, 0, &res)) { |
63 | ret = -ENOMEM; | |
64 | goto err_map; | |
65 | } | |
66 | ||
67 | base = ioremap(res.start, resource_size(&res)); | |
bdb0066d PD |
68 | if (!base) { |
69 | ret = -ENOMEM; | |
70 | goto err_map; | |
71 | } | |
72 | ||
73 | /* Parse the device's DT node for an endianness specification */ | |
74 | if (of_property_read_bool(np, "big-endian")) | |
75 | syscon_config.val_format_endian = REGMAP_ENDIAN_BIG; | |
76 | else if (of_property_read_bool(np, "little-endian")) | |
77 | syscon_config.val_format_endian = REGMAP_ENDIAN_LITTLE; | |
78 | ||
db2fb60c DR |
79 | /* |
80 | * search for reg-io-width property in DT. If it is not provided, | |
81 | * default to 4 bytes. regmap_init_mmio will return an error if values | |
82 | * are invalid so there is no need to check them here. | |
83 | */ | |
84 | ret = of_property_read_u32(np, "reg-io-width", ®_io_width); | |
85 | if (ret) | |
86 | reg_io_width = 4; | |
87 | ||
88 | syscon_config.reg_stride = reg_io_width; | |
89 | syscon_config.val_bits = reg_io_width * 8; | |
ca668f0e | 90 | syscon_config.max_register = resource_size(&res) - reg_io_width; |
db2fb60c | 91 | |
bdb0066d PD |
92 | regmap = regmap_init_mmio(NULL, base, &syscon_config); |
93 | if (IS_ERR(regmap)) { | |
94 | pr_err("regmap init failed\n"); | |
95 | ret = PTR_ERR(regmap); | |
96 | goto err_regmap; | |
97 | } | |
98 | ||
99 | syscon->regmap = regmap; | |
100 | syscon->np = np; | |
101 | ||
102 | spin_lock(&syscon_list_slock); | |
103 | list_add_tail(&syscon->list, &syscon_list); | |
104 | spin_unlock(&syscon_list_slock); | |
87d68730 | 105 | |
bdb0066d PD |
106 | return syscon; |
107 | ||
108 | err_regmap: | |
109 | iounmap(base); | |
110 | err_map: | |
111 | kfree(syscon); | |
112 | return ERR_PTR(ret); | |
87d68730 DA |
113 | } |
114 | ||
115 | struct regmap *syscon_node_to_regmap(struct device_node *np) | |
116 | { | |
bdb0066d | 117 | struct syscon *entry, *syscon = NULL; |
87d68730 | 118 | |
bdb0066d | 119 | spin_lock(&syscon_list_slock); |
87d68730 | 120 | |
bdb0066d PD |
121 | list_for_each_entry(entry, &syscon_list, list) |
122 | if (entry->np == np) { | |
123 | syscon = entry; | |
124 | break; | |
125 | } | |
126 | ||
127 | spin_unlock(&syscon_list_slock); | |
128 | ||
129 | if (!syscon) | |
130 | syscon = of_syscon_register(np); | |
131 | ||
132 | if (IS_ERR(syscon)) | |
133 | return ERR_CAST(syscon); | |
87d68730 DA |
134 | |
135 | return syscon->regmap; | |
136 | } | |
137 | EXPORT_SYMBOL_GPL(syscon_node_to_regmap); | |
138 | ||
139 | struct regmap *syscon_regmap_lookup_by_compatible(const char *s) | |
140 | { | |
141 | struct device_node *syscon_np; | |
142 | struct regmap *regmap; | |
143 | ||
144 | syscon_np = of_find_compatible_node(NULL, NULL, s); | |
145 | if (!syscon_np) | |
146 | return ERR_PTR(-ENODEV); | |
147 | ||
148 | regmap = syscon_node_to_regmap(syscon_np); | |
149 | of_node_put(syscon_np); | |
150 | ||
151 | return regmap; | |
152 | } | |
153 | EXPORT_SYMBOL_GPL(syscon_regmap_lookup_by_compatible); | |
154 | ||
5ab3a89a AS |
155 | static int syscon_match_pdevname(struct device *dev, void *data) |
156 | { | |
5ab3a89a AS |
157 | return !strcmp(dev_name(dev), (const char *)data); |
158 | } | |
159 | ||
160 | struct regmap *syscon_regmap_lookup_by_pdevname(const char *s) | |
161 | { | |
162 | struct device *dev; | |
163 | struct syscon *syscon; | |
164 | ||
165 | dev = driver_find_device(&syscon_driver.driver, NULL, (void *)s, | |
166 | syscon_match_pdevname); | |
167 | if (!dev) | |
168 | return ERR_PTR(-EPROBE_DEFER); | |
169 | ||
170 | syscon = dev_get_drvdata(dev); | |
171 | ||
172 | return syscon->regmap; | |
173 | } | |
174 | EXPORT_SYMBOL_GPL(syscon_regmap_lookup_by_pdevname); | |
175 | ||
87d68730 DA |
176 | struct regmap *syscon_regmap_lookup_by_phandle(struct device_node *np, |
177 | const char *property) | |
178 | { | |
179 | struct device_node *syscon_np; | |
180 | struct regmap *regmap; | |
181 | ||
45330bb4 PD |
182 | if (property) |
183 | syscon_np = of_parse_phandle(np, property, 0); | |
184 | else | |
185 | syscon_np = np; | |
186 | ||
87d68730 DA |
187 | if (!syscon_np) |
188 | return ERR_PTR(-ENODEV); | |
189 | ||
190 | regmap = syscon_node_to_regmap(syscon_np); | |
191 | of_node_put(syscon_np); | |
192 | ||
193 | return regmap; | |
194 | } | |
195 | EXPORT_SYMBOL_GPL(syscon_regmap_lookup_by_phandle); | |
196 | ||
f791be49 | 197 | static int syscon_probe(struct platform_device *pdev) |
87d68730 DA |
198 | { |
199 | struct device *dev = &pdev->dev; | |
29f9b6cf | 200 | struct syscon_platform_data *pdata = dev_get_platdata(dev); |
87d68730 | 201 | struct syscon *syscon; |
c131045d | 202 | struct regmap_config syscon_config = syscon_regmap_config; |
5ab3a89a | 203 | struct resource *res; |
f10111cc | 204 | void __iomem *base; |
87d68730 | 205 | |
5ab3a89a | 206 | syscon = devm_kzalloc(dev, sizeof(*syscon), GFP_KERNEL); |
87d68730 DA |
207 | if (!syscon) |
208 | return -ENOMEM; | |
209 | ||
5ab3a89a AS |
210 | res = platform_get_resource(pdev, IORESOURCE_MEM, 0); |
211 | if (!res) | |
212 | return -ENOENT; | |
87d68730 | 213 | |
f10111cc AS |
214 | base = devm_ioremap(dev, res->start, resource_size(res)); |
215 | if (!base) | |
5ab3a89a | 216 | return -ENOMEM; |
87d68730 | 217 | |
c131045d | 218 | syscon_config.max_register = res->end - res->start - 3; |
29f9b6cf | 219 | if (pdata) |
c131045d PZ |
220 | syscon_config.name = pdata->label; |
221 | syscon->regmap = devm_regmap_init_mmio(dev, base, &syscon_config); | |
87d68730 DA |
222 | if (IS_ERR(syscon->regmap)) { |
223 | dev_err(dev, "regmap init failed\n"); | |
224 | return PTR_ERR(syscon->regmap); | |
225 | } | |
226 | ||
87d68730 DA |
227 | platform_set_drvdata(pdev, syscon); |
228 | ||
38d8974e | 229 | dev_dbg(dev, "regmap %pR registered\n", res); |
87d68730 DA |
230 | |
231 | return 0; | |
232 | } | |
233 | ||
5ab3a89a AS |
234 | static const struct platform_device_id syscon_ids[] = { |
235 | { "syscon", }, | |
236 | { } | |
237 | }; | |
87d68730 DA |
238 | |
239 | static struct platform_driver syscon_driver = { | |
240 | .driver = { | |
241 | .name = "syscon", | |
87d68730 DA |
242 | }, |
243 | .probe = syscon_probe, | |
5ab3a89a | 244 | .id_table = syscon_ids, |
87d68730 DA |
245 | }; |
246 | ||
247 | static int __init syscon_init(void) | |
248 | { | |
249 | return platform_driver_register(&syscon_driver); | |
250 | } | |
251 | postcore_initcall(syscon_init); | |
252 | ||
253 | static void __exit syscon_exit(void) | |
254 | { | |
255 | platform_driver_unregister(&syscon_driver); | |
256 | } | |
257 | module_exit(syscon_exit); | |
258 | ||
259 | MODULE_AUTHOR("Dong Aisheng <dong.aisheng@linaro.org>"); | |
260 | MODULE_DESCRIPTION("System Control driver"); | |
261 | MODULE_LICENSE("GPL v2"); |