xref: /linux/drivers/macintosh/ams/ams-core.c (revision 132db93572821ec2fdf81e354cc40f558faf7e4f)
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! */
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 
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 snprintf(buf, PAGE_SIZE, "%d %d %d\n", x, y, z);
54 }
55 
56 static DEVICE_ATTR(current, S_IRUGO, ams_show_current, NULL);
57 
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  */
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! */
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 
179 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 
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 
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