xref: /openbmc/linux/drivers/macintosh/ams/ams-core.c (revision 95e9fd10)
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 bool 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_sensor_detach(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 	/* Flush interrupt worker
225 	 *
226 	 * We do this after ams_info.exit(), because an interrupt might
227 	 * have arrived before disabling them.
228 	 */
229 	flush_work_sync(&ams_info.worker);
230 
231 	/* Remove device */
232 	of_device_unregister(ams_info.of_dev);
233 
234 	/* Remove handler */
235 	pmf_unregister_irq_client(&ams_shock_client);
236 	pmf_unregister_irq_client(&ams_freefall_client);
237 }
238 
239 static void __exit ams_exit(void)
240 {
241 	/* Shut down implementation */
242 	ams_info.exit();
243 }
244 
245 MODULE_AUTHOR("Stelian Pop, Michael Hanselmann");
246 MODULE_DESCRIPTION("Apple Motion Sensor driver");
247 MODULE_LICENSE("GPL");
248 
249 module_init(ams_init);
250 module_exit(ams_exit);
251