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1 | /* |
2 | * Copyright (C) 2009-2010, Lars-Peter Clausen <lars@metafoo.de> |
3 | * JZ4740 SoC HWMON driver |
4 | * |
5 | * This program is free software; you can redistribute it and/or modify it |
6 | * under the terms of the GNU General Public License as published by the |
7 | * Free Software Foundation; either version 2 of the License, or (at your |
8 | * option) any later version. |
9 | * |
10 | * You should have received a copy of the GNU General Public License along |
11 | * with this program; if not, write to the Free Software Foundation, Inc., |
12 | * 675 Mass Ave, Cambridge, MA 02139, USA. |
13 | * |
14 | */ |
15 | |
16 | #include <linux/err.h> |
17 | #include <linux/interrupt.h> |
18 | #include <linux/kernel.h> |
19 | #include <linux/module.h> |
20 | #include <linux/mutex.h> |
21 | #include <linux/platform_device.h> |
22 | #include <linux/slab.h> |
23 | |
24 | #include <linux/completion.h> |
25 | #include <linux/mfd/core.h> |
26 | |
27 | #include <linux/hwmon.h> |
28 | |
29 | struct jz4740_hwmon { |
30 | struct resource *mem; |
31 | void __iomem *base; |
32 | |
33 | int irq; |
34 | |
35 | const struct mfd_cell *cell; |
36 | struct device *hwmon; |
37 | |
38 | struct completion read_completion; |
39 | |
40 | struct mutex lock; |
41 | }; |
42 | |
43 | static ssize_t jz4740_hwmon_show_name(struct device *dev, |
44 | struct device_attribute *dev_attr, char *buf) |
45 | { |
46 | return sprintf(buf, "jz4740\n"); |
47 | } |
48 | |
49 | static irqreturn_t jz4740_hwmon_irq(int irq, void *data) |
50 | { |
51 | struct jz4740_hwmon *hwmon = data; |
52 | |
53 | complete(&hwmon->read_completion); |
54 | return IRQ_HANDLED; |
55 | } |
56 | |
57 | static ssize_t jz4740_hwmon_read_adcin(struct device *dev, |
58 | struct device_attribute *dev_attr, char *buf) |
59 | { |
60 | struct jz4740_hwmon *hwmon = dev_get_drvdata(dev); |
61 | struct completion *completion = &hwmon->read_completion; |
62 | long t; |
63 | unsigned long val; |
64 | int ret; |
65 | |
66 | mutex_lock(&hwmon->lock); |
67 | |
68 | INIT_COMPLETION(*completion); |
69 | |
70 | enable_irq(hwmon->irq); |
71 | hwmon->cell->enable(to_platform_device(dev)); |
72 | |
73 | t = wait_for_completion_interruptible_timeout(completion, HZ); |
74 | |
75 | if (t > 0) { |
76 | val = readw(hwmon->base) & 0xfff; |
77 | val = (val * 3300) >> 12; |
78 | ret = sprintf(buf, "%lu\n", val); |
79 | } else { |
80 | ret = t ? t : -ETIMEDOUT; |
81 | } |
82 | |
83 | hwmon->cell->disable(to_platform_device(dev)); |
84 | disable_irq(hwmon->irq); |
85 | |
86 | mutex_unlock(&hwmon->lock); |
87 | |
88 | return ret; |
89 | } |
90 | |
91 | static DEVICE_ATTR(name, S_IRUGO, jz4740_hwmon_show_name, NULL); |
92 | static DEVICE_ATTR(in0_input, S_IRUGO, jz4740_hwmon_read_adcin, NULL); |
93 | |
94 | static struct attribute *jz4740_hwmon_attributes[] = { |
95 | &dev_attr_name.attr, |
96 | &dev_attr_in0_input.attr, |
97 | NULL |
98 | }; |
99 | |
100 | static const struct attribute_group jz4740_hwmon_attr_group = { |
101 | .attrs = jz4740_hwmon_attributes, |
102 | }; |
103 | |
104 | static int __devinit jz4740_hwmon_probe(struct platform_device *pdev) |
105 | { |
106 | int ret; |
107 | struct jz4740_hwmon *hwmon; |
108 | |
109 | hwmon = kmalloc(sizeof(*hwmon), GFP_KERNEL); |
110 | if (!hwmon) { |
111 | dev_err(&pdev->dev, "Failed to allocate driver structure\n"); |
112 | return -ENOMEM; |
113 | } |
114 | |
115 | hwmon->cell = mfd_get_cell(pdev); |
116 | |
117 | hwmon->irq = platform_get_irq(pdev, 0); |
118 | if (hwmon->irq < 0) { |
119 | ret = hwmon->irq; |
120 | dev_err(&pdev->dev, "Failed to get platform irq: %d\n", ret); |
121 | goto err_free; |
122 | } |
123 | |
124 | hwmon->mem = platform_get_resource(pdev, IORESOURCE_MEM, 0); |
125 | if (!hwmon->mem) { |
126 | ret = -ENOENT; |
127 | dev_err(&pdev->dev, "Failed to get platform mmio resource\n"); |
128 | goto err_free; |
129 | } |
130 | |
131 | hwmon->mem = request_mem_region(hwmon->mem->start, |
132 | resource_size(hwmon->mem), pdev->name); |
133 | if (!hwmon->mem) { |
134 | ret = -EBUSY; |
135 | dev_err(&pdev->dev, "Failed to request mmio memory region\n"); |
136 | goto err_free; |
137 | } |
138 | |
139 | hwmon->base = ioremap_nocache(hwmon->mem->start, |
140 | resource_size(hwmon->mem)); |
141 | if (!hwmon->base) { |
142 | ret = -EBUSY; |
143 | dev_err(&pdev->dev, "Failed to ioremap mmio memory\n"); |
144 | goto err_release_mem_region; |
145 | } |
146 | |
147 | init_completion(&hwmon->read_completion); |
148 | mutex_init(&hwmon->lock); |
149 | |
150 | platform_set_drvdata(pdev, hwmon); |
151 | |
152 | ret = request_irq(hwmon->irq, jz4740_hwmon_irq, 0, pdev->name, hwmon); |
153 | if (ret) { |
154 | dev_err(&pdev->dev, "Failed to request irq: %d\n", ret); |
155 | goto err_iounmap; |
156 | } |
157 | disable_irq(hwmon->irq); |
158 | |
159 | ret = sysfs_create_group(&pdev->dev.kobj, &jz4740_hwmon_attr_group); |
160 | if (ret) { |
161 | dev_err(&pdev->dev, "Failed to create sysfs group: %d\n", ret); |
162 | goto err_free_irq; |
163 | } |
164 | |
165 | hwmon->hwmon = hwmon_device_register(&pdev->dev); |
166 | if (IS_ERR(hwmon->hwmon)) { |
167 | ret = PTR_ERR(hwmon->hwmon); |
168 | goto err_remove_file; |
169 | } |
170 | |
171 | return 0; |
172 | |
173 | err_remove_file: |
174 | sysfs_remove_group(&pdev->dev.kobj, &jz4740_hwmon_attr_group); |
175 | err_free_irq: |
176 | free_irq(hwmon->irq, hwmon); |
177 | err_iounmap: |
178 | platform_set_drvdata(pdev, NULL); |
179 | iounmap(hwmon->base); |
180 | err_release_mem_region: |
181 | release_mem_region(hwmon->mem->start, resource_size(hwmon->mem)); |
182 | err_free: |
183 | kfree(hwmon); |
184 | |
185 | return ret; |
186 | } |
187 | |
188 | static int __devexit jz4740_hwmon_remove(struct platform_device *pdev) |
189 | { |
190 | struct jz4740_hwmon *hwmon = platform_get_drvdata(pdev); |
191 | |
192 | hwmon_device_unregister(hwmon->hwmon); |
193 | sysfs_remove_group(&pdev->dev.kobj, &jz4740_hwmon_attr_group); |
194 | |
195 | free_irq(hwmon->irq, hwmon); |
196 | |
197 | iounmap(hwmon->base); |
198 | release_mem_region(hwmon->mem->start, resource_size(hwmon->mem)); |
199 | |
200 | platform_set_drvdata(pdev, NULL); |
201 | kfree(hwmon); |
202 | |
203 | return 0; |
204 | } |
205 | |
206 | static struct platform_driver jz4740_hwmon_driver = { |
207 | .probe = jz4740_hwmon_probe, |
208 | .remove = __devexit_p(jz4740_hwmon_remove), |
209 | .driver = { |
210 | .name = "jz4740-hwmon", |
211 | .owner = THIS_MODULE, |
212 | }, |
213 | }; |
214 | |
215 | module_platform_driver(jz4740_hwmon_driver); |
216 | |
217 | MODULE_DESCRIPTION("JZ4740 SoC HWMON driver"); |
218 | MODULE_AUTHOR("Lars-Peter Clausen <lars@metafoo.de>"); |
219 | MODULE_LICENSE("GPL"); |
220 | MODULE_ALIAS("platform:jz4740-hwmon"); |
221 |
Branches:
ben-wpan
ben-wpan-stefan
javiroman/ks7010
jz-2.6.34
jz-2.6.34-rc5
jz-2.6.34-rc6
jz-2.6.34-rc7
jz-2.6.35
jz-2.6.36
jz-2.6.37
jz-2.6.38
jz-2.6.39
jz-3.0
jz-3.1
jz-3.11
jz-3.12
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jz-3.15
jz-3.16
jz-3.18-dt
jz-3.2
jz-3.3
jz-3.4
jz-3.5
jz-3.6
jz-3.6-rc2-pwm
jz-3.9
jz-3.9-clk
jz-3.9-rc8
jz47xx
jz47xx-2.6.38
master
Tags:
od-2011-09-04
od-2011-09-18
v2.6.34-rc5
v2.6.34-rc6
v2.6.34-rc7
v3.9