1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3 * Apple Motion Sensor driver
4 *
5 * Copyright (C) 2005 Stelian Pop (stelian@popies.net)
6 * Copyright (C) 2006 Michael Hanselmann (linux-kernel@hansmi.ch)
7 */
8
9 #include <linux/module.h>
10 #include <linux/types.h>
11 #include <linux/errno.h>
12 #include <linux/init.h>
13 #include <linux/of_platform.h>
14 #include <asm/pmac_pfunc.h>
15
16 #include "ams.h"
17
18 /* There is only one motion sensor per machine */
19 struct ams ams_info;
20
21 static bool verbose;
22 module_param(verbose, bool, 0644);
23 MODULE_PARM_DESC(verbose, "Show free falls and shocks in kernel output");
24
25 /* Call with ams_info.lock held! */
ams_sensors(s8 * x,s8 * y,s8 * z)26 void ams_sensors(s8 *x, s8 *y, s8 *z)
27 {
28 u32 orient = ams_info.vflag? ams_info.orient1 : ams_info.orient2;
29
30 if (orient & 0x80)
31 /* X and Y swapped */
32 ams_info.get_xyz(y, x, z);
33 else
34 ams_info.get_xyz(x, y, z);
35
36 if (orient & 0x04)
37 *z = ~(*z);
38 if (orient & 0x02)
39 *y = ~(*y);
40 if (orient & 0x01)
41 *x = ~(*x);
42 }
43
ams_show_current(struct device * dev,struct device_attribute * attr,char * buf)44 static ssize_t ams_show_current(struct device *dev,
45 struct device_attribute *attr, char *buf)
46 {
47 s8 x, y, z;
48
49 mutex_lock(&ams_info.lock);
50 ams_sensors(&x, &y, &z);
51 mutex_unlock(&ams_info.lock);
52
53 return sysfs_emit(buf, "%d %d %d\n", x, y, z);
54 }
55
56 static DEVICE_ATTR(current, S_IRUGO, ams_show_current, NULL);
57
ams_handle_irq(void * data)58 static void ams_handle_irq(void *data)
59 {
60 enum ams_irq irq = *((enum ams_irq *)data);
61
62 spin_lock(&ams_info.irq_lock);
63
64 ams_info.worker_irqs |= irq;
65 schedule_work(&ams_info.worker);
66
67 spin_unlock(&ams_info.irq_lock);
68 }
69
70 static enum ams_irq ams_freefall_irq_data = AMS_IRQ_FREEFALL;
71 static struct pmf_irq_client ams_freefall_client = {
72 .owner = THIS_MODULE,
73 .handler = ams_handle_irq,
74 .data = &ams_freefall_irq_data,
75 };
76
77 static enum ams_irq ams_shock_irq_data = AMS_IRQ_SHOCK;
78 static struct pmf_irq_client ams_shock_client = {
79 .owner = THIS_MODULE,
80 .handler = ams_handle_irq,
81 .data = &ams_shock_irq_data,
82 };
83
84 /* Once hard disk parking is implemented in the kernel, this function can
85 * trigger it.
86 */
ams_worker(struct work_struct * work)87 static void ams_worker(struct work_struct *work)
88 {
89 unsigned long flags;
90 u8 irqs_to_clear;
91
92 mutex_lock(&ams_info.lock);
93
94 spin_lock_irqsave(&ams_info.irq_lock, flags);
95 irqs_to_clear = ams_info.worker_irqs;
96
97 if (ams_info.worker_irqs & AMS_IRQ_FREEFALL) {
98 if (verbose)
99 printk(KERN_INFO "ams: freefall detected!\n");
100
101 ams_info.worker_irqs &= ~AMS_IRQ_FREEFALL;
102 }
103
104 if (ams_info.worker_irqs & AMS_IRQ_SHOCK) {
105 if (verbose)
106 printk(KERN_INFO "ams: shock detected!\n");
107
108 ams_info.worker_irqs &= ~AMS_IRQ_SHOCK;
109 }
110
111 spin_unlock_irqrestore(&ams_info.irq_lock, flags);
112
113 ams_info.clear_irq(irqs_to_clear);
114
115 mutex_unlock(&ams_info.lock);
116 }
117
118 /* Call with ams_info.lock held! */
ams_sensor_attach(void)119 int ams_sensor_attach(void)
120 {
121 int result;
122 const u32 *prop;
123
124 /* Get orientation */
125 prop = of_get_property(ams_info.of_node, "orientation", NULL);
126 if (!prop)
127 return -ENODEV;
128 ams_info.orient1 = *prop;
129 ams_info.orient2 = *(prop + 1);
130
131 /* Register freefall interrupt handler */
132 result = pmf_register_irq_client(ams_info.of_node,
133 "accel-int-1",
134 &ams_freefall_client);
135 if (result < 0)
136 return -ENODEV;
137
138 /* Reset saved irqs */
139 ams_info.worker_irqs = 0;
140
141 /* Register shock interrupt handler */
142 result = pmf_register_irq_client(ams_info.of_node,
143 "accel-int-2",
144 &ams_shock_client);
145 if (result < 0)
146 goto release_freefall;
147
148 /* Create device */
149 ams_info.of_dev = of_platform_device_create(ams_info.of_node, "ams", NULL);
150 if (!ams_info.of_dev) {
151 result = -ENODEV;
152 goto release_shock;
153 }
154
155 /* Create attributes */
156 result = device_create_file(&ams_info.of_dev->dev, &dev_attr_current);
157 if (result)
158 goto release_of;
159
160 ams_info.vflag = !!(ams_info.get_vendor() & 0x10);
161
162 /* Init input device */
163 result = ams_input_init();
164 if (result)
165 goto release_device_file;
166
167 return result;
168 release_device_file:
169 device_remove_file(&ams_info.of_dev->dev, &dev_attr_current);
170 release_of:
171 of_device_unregister(ams_info.of_dev);
172 release_shock:
173 pmf_unregister_irq_client(&ams_shock_client);
174 release_freefall:
175 pmf_unregister_irq_client(&ams_freefall_client);
176 return result;
177 }
178
ams_init(void)179 static int __init ams_init(void)
180 {
181 struct device_node *np;
182
183 spin_lock_init(&ams_info.irq_lock);
184 mutex_init(&ams_info.lock);
185 INIT_WORK(&ams_info.worker, ams_worker);
186
187 #ifdef CONFIG_SENSORS_AMS_I2C
188 np = of_find_node_by_name(NULL, "accelerometer");
189 if (np && of_device_is_compatible(np, "AAPL,accelerometer_1"))
190 /* Found I2C motion sensor */
191 return ams_i2c_init(np);
192 #endif
193
194 #ifdef CONFIG_SENSORS_AMS_PMU
195 np = of_find_node_by_name(NULL, "sms");
196 if (np && of_device_is_compatible(np, "sms"))
197 /* Found PMU motion sensor */
198 return ams_pmu_init(np);
199 #endif
200 return -ENODEV;
201 }
202
ams_sensor_detach(void)203 void ams_sensor_detach(void)
204 {
205 /* Remove input device */
206 ams_input_exit();
207
208 /* Remove attributes */
209 device_remove_file(&ams_info.of_dev->dev, &dev_attr_current);
210
211 /* Flush interrupt worker
212 *
213 * We do this after ams_info.exit(), because an interrupt might
214 * have arrived before disabling them.
215 */
216 flush_work(&ams_info.worker);
217
218 /* Remove device */
219 of_device_unregister(ams_info.of_dev);
220
221 /* Remove handler */
222 pmf_unregister_irq_client(&ams_shock_client);
223 pmf_unregister_irq_client(&ams_freefall_client);
224 }
225
ams_exit(void)226 static void __exit ams_exit(void)
227 {
228 /* Shut down implementation */
229 ams_info.exit();
230 }
231
232 MODULE_AUTHOR("Stelian Pop, Michael Hanselmann");
233 MODULE_DESCRIPTION("Apple Motion Sensor driver");
234 MODULE_LICENSE("GPL");
235
236 module_init(ams_init);
237 module_exit(ams_exit);
238