Merge branch 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/btrfs...
[linux-2.6] / drivers / hwmon / ams / ams-core.c
1 /*
2  * Apple Motion Sensor driver
3  *
4  * Copyright (C) 2005 Stelian Pop (stelian@popies.net)
5  * Copyright (C) 2006 Michael Hanselmann (linux-kernel@hansmi.ch)
6  *
7  * This program is free software; you can redistribute it and/or modify
8  * it under the terms of the GNU General Public License as published by
9  * the Free Software Foundation; either version 2 of the License, or
10  * (at your option) any later version.
11  *
12  * This program is distributed in the hope that it will be useful,
13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
15  * GNU General Public License for more details.
16  *
17  * You should have received a copy of the GNU General Public License
18  * along with this program; if not, write to the Free Software
19  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
20  */
21
22 #include <linux/module.h>
23 #include <linux/types.h>
24 #include <linux/errno.h>
25 #include <linux/init.h>
26 #include <linux/of_platform.h>
27 #include <asm/pmac_pfunc.h>
28
29 #include "ams.h"
30
31 /* There is only one motion sensor per machine */
32 struct ams ams_info;
33
34 static unsigned int verbose;
35 module_param(verbose, bool, 0644);
36 MODULE_PARM_DESC(verbose, "Show free falls and shocks in kernel output");
37
38 /* Call with ams_info.lock held! */
39 void ams_sensors(s8 *x, s8 *y, s8 *z)
40 {
41         u32 orient = ams_info.vflag? ams_info.orient1 : ams_info.orient2;
42
43         if (orient & 0x80)
44                 /* X and Y swapped */
45                 ams_info.get_xyz(y, x, z);
46         else
47                 ams_info.get_xyz(x, y, z);
48
49         if (orient & 0x04)
50                 *z = ~(*z);
51         if (orient & 0x02)
52                 *y = ~(*y);
53         if (orient & 0x01)
54                 *x = ~(*x);
55 }
56
57 static ssize_t ams_show_current(struct device *dev,
58         struct device_attribute *attr, char *buf)
59 {
60         s8 x, y, z;
61
62         mutex_lock(&ams_info.lock);
63         ams_sensors(&x, &y, &z);
64         mutex_unlock(&ams_info.lock);
65
66         return snprintf(buf, PAGE_SIZE, "%d %d %d\n", x, y, z);
67 }
68
69 static DEVICE_ATTR(current, S_IRUGO, ams_show_current, NULL);
70
71 static void ams_handle_irq(void *data)
72 {
73         enum ams_irq irq = *((enum ams_irq *)data);
74
75         spin_lock(&ams_info.irq_lock);
76
77         ams_info.worker_irqs |= irq;
78         schedule_work(&ams_info.worker);
79
80         spin_unlock(&ams_info.irq_lock);
81 }
82
83 static enum ams_irq ams_freefall_irq_data = AMS_IRQ_FREEFALL;
84 static struct pmf_irq_client ams_freefall_client = {
85         .owner = THIS_MODULE,
86         .handler = ams_handle_irq,
87         .data = &ams_freefall_irq_data,
88 };
89
90 static enum ams_irq ams_shock_irq_data = AMS_IRQ_SHOCK;
91 static struct pmf_irq_client ams_shock_client = {
92         .owner = THIS_MODULE,
93         .handler = ams_handle_irq,
94         .data = &ams_shock_irq_data,
95 };
96
97 /* Once hard disk parking is implemented in the kernel, this function can
98  * trigger it.
99  */
100 static void ams_worker(struct work_struct *work)
101 {
102         unsigned long flags;
103         u8 irqs_to_clear;
104
105         mutex_lock(&ams_info.lock);
106
107         spin_lock_irqsave(&ams_info.irq_lock, flags);
108         irqs_to_clear = ams_info.worker_irqs;
109
110         if (ams_info.worker_irqs & AMS_IRQ_FREEFALL) {
111                 if (verbose)
112                         printk(KERN_INFO "ams: freefall detected!\n");
113
114                 ams_info.worker_irqs &= ~AMS_IRQ_FREEFALL;
115         }
116
117         if (ams_info.worker_irqs & AMS_IRQ_SHOCK) {
118                 if (verbose)
119                         printk(KERN_INFO "ams: shock detected!\n");
120
121                 ams_info.worker_irqs &= ~AMS_IRQ_SHOCK;
122         }
123
124         spin_unlock_irqrestore(&ams_info.irq_lock, flags);
125
126         ams_info.clear_irq(irqs_to_clear);
127
128         mutex_unlock(&ams_info.lock);
129 }
130
131 /* Call with ams_info.lock held! */
132 int ams_sensor_attach(void)
133 {
134         int result;
135         const u32 *prop;
136
137         /* Get orientation */
138         prop = of_get_property(ams_info.of_node, "orientation", NULL);
139         if (!prop)
140                 return -ENODEV;
141         ams_info.orient1 = *prop;
142         ams_info.orient2 = *(prop + 1);
143
144         /* Register freefall interrupt handler */
145         result = pmf_register_irq_client(ams_info.of_node,
146                         "accel-int-1",
147                         &ams_freefall_client);
148         if (result < 0)
149                 return -ENODEV;
150
151         /* Reset saved irqs */
152         ams_info.worker_irqs = 0;
153
154         /* Register shock interrupt handler */
155         result = pmf_register_irq_client(ams_info.of_node,
156                         "accel-int-2",
157                         &ams_shock_client);
158         if (result < 0)
159                 goto release_freefall;
160
161         /* Create device */
162         ams_info.of_dev = of_platform_device_create(ams_info.of_node, "ams", NULL);
163         if (!ams_info.of_dev) {
164                 result = -ENODEV;
165                 goto release_shock;
166         }
167
168         /* Create attributes */
169         result = device_create_file(&ams_info.of_dev->dev, &dev_attr_current);
170         if (result)
171                 goto release_of;
172
173         ams_info.vflag = !!(ams_info.get_vendor() & 0x10);
174
175         /* Init input device */
176         result = ams_input_init();
177         if (result)
178                 goto release_device_file;
179
180         return result;
181 release_device_file:
182         device_remove_file(&ams_info.of_dev->dev, &dev_attr_current);
183 release_of:
184         of_device_unregister(ams_info.of_dev);
185 release_shock:
186         pmf_unregister_irq_client(&ams_shock_client);
187 release_freefall:
188         pmf_unregister_irq_client(&ams_freefall_client);
189         return result;
190 }
191
192 int __init ams_init(void)
193 {
194         struct device_node *np;
195
196         spin_lock_init(&ams_info.irq_lock);
197         mutex_init(&ams_info.lock);
198         INIT_WORK(&ams_info.worker, ams_worker);
199
200 #ifdef CONFIG_SENSORS_AMS_I2C
201         np = of_find_node_by_name(NULL, "accelerometer");
202         if (np && of_device_is_compatible(np, "AAPL,accelerometer_1"))
203                 /* Found I2C motion sensor */
204                 return ams_i2c_init(np);
205 #endif
206
207 #ifdef CONFIG_SENSORS_AMS_PMU
208         np = of_find_node_by_name(NULL, "sms");
209         if (np && of_device_is_compatible(np, "sms"))
210                 /* Found PMU motion sensor */
211                 return ams_pmu_init(np);
212 #endif
213         return -ENODEV;
214 }
215
216 void ams_exit(void)
217 {
218         /* Remove input device */
219         ams_input_exit();
220
221         /* Remove attributes */
222         device_remove_file(&ams_info.of_dev->dev, &dev_attr_current);
223
224         /* Shut down implementation */
225         ams_info.exit();
226
227         /* Flush interrupt worker
228          *
229          * We do this after ams_info.exit(), because an interrupt might
230          * have arrived before disabling them.
231          */
232         flush_scheduled_work();
233
234         /* Remove device */
235         of_device_unregister(ams_info.of_dev);
236
237         /* Remove handler */
238         pmf_unregister_irq_client(&ams_shock_client);
239         pmf_unregister_irq_client(&ams_freefall_client);
240 }
241
242 MODULE_AUTHOR("Stelian Pop, Michael Hanselmann");
243 MODULE_DESCRIPTION("Apple Motion Sensor driver");
244 MODULE_LICENSE("GPL");
245
246 module_init(ams_init);
247 module_exit(ams_exit);