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1// SPDX-License-Identifier: GPL-2.0-or-later
2/*
3 * Apple Motion Sensor driver (I2C variant)
4 *
5 * Copyright (C) 2005 Stelian Pop (stelian@popies.net)
6 * Copyright (C) 2006 Michael Hanselmann (linux-kernel@hansmi.ch)
7 *
8 * Clean room implementation based on the reverse engineered Mac OS X driver by
9 * Johannes Berg <johannes@sipsolutions.net>, documentation available at
10 * http://johannes.sipsolutions.net/PowerBook/Apple_Motion_Sensor_Specification
11 */
12
13#include <linux/module.h>
14#include <linux/types.h>
15#include <linux/errno.h>
16#include <linux/init.h>
17#include <linux/delay.h>
18
19#include "ams.h"
20
21/* AMS registers */
22#define AMS_COMMAND 0x00 /* command register */
23#define AMS_STATUS 0x01 /* status register */
24#define AMS_CTRL1 0x02 /* read control 1 (number of values) */
25#define AMS_CTRL2 0x03 /* read control 2 (offset?) */
26#define AMS_CTRL3 0x04 /* read control 3 (size of each value?) */
27#define AMS_DATA1 0x05 /* read data 1 */
28#define AMS_DATA2 0x06 /* read data 2 */
29#define AMS_DATA3 0x07 /* read data 3 */
30#define AMS_DATA4 0x08 /* read data 4 */
31#define AMS_DATAX 0x20 /* data X */
32#define AMS_DATAY 0x21 /* data Y */
33#define AMS_DATAZ 0x22 /* data Z */
34#define AMS_FREEFALL 0x24 /* freefall int control */
35#define AMS_SHOCK 0x25 /* shock int control */
36#define AMS_SENSLOW 0x26 /* sensitivity low limit */
37#define AMS_SENSHIGH 0x27 /* sensitivity high limit */
38#define AMS_CTRLX 0x28 /* control X */
39#define AMS_CTRLY 0x29 /* control Y */
40#define AMS_CTRLZ 0x2A /* control Z */
41#define AMS_UNKNOWN1 0x2B /* unknown 1 */
42#define AMS_UNKNOWN2 0x2C /* unknown 2 */
43#define AMS_UNKNOWN3 0x2D /* unknown 3 */
44#define AMS_VENDOR 0x2E /* vendor */
45
46/* AMS commands - use with the AMS_COMMAND register */
47enum ams_i2c_cmd {
48 AMS_CMD_NOOP = 0,
49 AMS_CMD_VERSION,
50 AMS_CMD_READMEM,
51 AMS_CMD_WRITEMEM,
52 AMS_CMD_ERASEMEM,
53 AMS_CMD_READEE,
54 AMS_CMD_WRITEEE,
55 AMS_CMD_RESET,
56 AMS_CMD_START,
57};
58
59static int ams_i2c_probe(struct i2c_client *client,
60 const struct i2c_device_id *id);
61static int ams_i2c_remove(struct i2c_client *client);
62
63static const struct i2c_device_id ams_id[] = {
64 { "MAC,accelerometer_1", 0 },
65 { }
66};
67MODULE_DEVICE_TABLE(i2c, ams_id);
68
69static struct i2c_driver ams_i2c_driver = {
70 .driver = {
71 .name = "ams",
72 },
73 .probe = ams_i2c_probe,
74 .remove = ams_i2c_remove,
75 .id_table = ams_id,
76};
77
78static s32 ams_i2c_read(u8 reg)
79{
80 return i2c_smbus_read_byte_data(ams_info.i2c_client, reg);
81}
82
83static int ams_i2c_write(u8 reg, u8 value)
84{
85 return i2c_smbus_write_byte_data(ams_info.i2c_client, reg, value);
86}
87
88static int ams_i2c_cmd(enum ams_i2c_cmd cmd)
89{
90 s32 result;
91 int count = 3;
92
93 ams_i2c_write(AMS_COMMAND, cmd);
94 msleep(5);
95
96 while (count--) {
97 result = ams_i2c_read(AMS_COMMAND);
98 if (result == 0 || result & 0x80)
99 return 0;
100
101 schedule_timeout_uninterruptible(HZ / 20);
102 }
103
104 return -1;
105}
106
107static void ams_i2c_set_irq(enum ams_irq reg, char enable)
108{
109 if (reg & AMS_IRQ_FREEFALL) {
110 u8 val = ams_i2c_read(AMS_CTRLX);
111 if (enable)
112 val |= 0x80;
113 else
114 val &= ~0x80;
115 ams_i2c_write(AMS_CTRLX, val);
116 }
117
118 if (reg & AMS_IRQ_SHOCK) {
119 u8 val = ams_i2c_read(AMS_CTRLY);
120 if (enable)
121 val |= 0x80;
122 else
123 val &= ~0x80;
124 ams_i2c_write(AMS_CTRLY, val);
125 }
126
127 if (reg & AMS_IRQ_GLOBAL) {
128 u8 val = ams_i2c_read(AMS_CTRLZ);
129 if (enable)
130 val |= 0x80;
131 else
132 val &= ~0x80;
133 ams_i2c_write(AMS_CTRLZ, val);
134 }
135}
136
137static void ams_i2c_clear_irq(enum ams_irq reg)
138{
139 if (reg & AMS_IRQ_FREEFALL)
140 ams_i2c_write(AMS_FREEFALL, 0);
141
142 if (reg & AMS_IRQ_SHOCK)
143 ams_i2c_write(AMS_SHOCK, 0);
144}
145
146static u8 ams_i2c_get_vendor(void)
147{
148 return ams_i2c_read(AMS_VENDOR);
149}
150
151static void ams_i2c_get_xyz(s8 *x, s8 *y, s8 *z)
152{
153 *x = ams_i2c_read(AMS_DATAX);
154 *y = ams_i2c_read(AMS_DATAY);
155 *z = ams_i2c_read(AMS_DATAZ);
156}
157
158static int ams_i2c_probe(struct i2c_client *client,
159 const struct i2c_device_id *id)
160{
161 int vmaj, vmin;
162 int result;
163
164 /* There can be only one */
165 if (unlikely(ams_info.has_device))
166 return -ENODEV;
167
168 ams_info.i2c_client = client;
169
170 if (ams_i2c_cmd(AMS_CMD_RESET)) {
171 printk(KERN_INFO "ams: Failed to reset the device\n");
172 return -ENODEV;
173 }
174
175 if (ams_i2c_cmd(AMS_CMD_START)) {
176 printk(KERN_INFO "ams: Failed to start the device\n");
177 return -ENODEV;
178 }
179
180 /* get version/vendor information */
181 ams_i2c_write(AMS_CTRL1, 0x02);
182 ams_i2c_write(AMS_CTRL2, 0x85);
183 ams_i2c_write(AMS_CTRL3, 0x01);
184
185 ams_i2c_cmd(AMS_CMD_READMEM);
186
187 vmaj = ams_i2c_read(AMS_DATA1);
188 vmin = ams_i2c_read(AMS_DATA2);
189 if (vmaj != 1 || vmin != 52) {
190 printk(KERN_INFO "ams: Incorrect device version (%d.%d)\n",
191 vmaj, vmin);
192 return -ENODEV;
193 }
194
195 ams_i2c_cmd(AMS_CMD_VERSION);
196
197 vmaj = ams_i2c_read(AMS_DATA1);
198 vmin = ams_i2c_read(AMS_DATA2);
199 if (vmaj != 0 || vmin != 1) {
200 printk(KERN_INFO "ams: Incorrect firmware version (%d.%d)\n",
201 vmaj, vmin);
202 return -ENODEV;
203 }
204
205 /* Disable interrupts */
206 ams_i2c_set_irq(AMS_IRQ_ALL, 0);
207
208 result = ams_sensor_attach();
209 if (result < 0)
210 return result;
211
212 /* Set default values */
213 ams_i2c_write(AMS_SENSLOW, 0x15);
214 ams_i2c_write(AMS_SENSHIGH, 0x60);
215 ams_i2c_write(AMS_CTRLX, 0x08);
216 ams_i2c_write(AMS_CTRLY, 0x0F);
217 ams_i2c_write(AMS_CTRLZ, 0x4F);
218 ams_i2c_write(AMS_UNKNOWN1, 0x14);
219
220 /* Clear interrupts */
221 ams_i2c_clear_irq(AMS_IRQ_ALL);
222
223 ams_info.has_device = 1;
224
225 /* Enable interrupts */
226 ams_i2c_set_irq(AMS_IRQ_ALL, 1);
227
228 printk(KERN_INFO "ams: Found I2C based motion sensor\n");
229
230 return 0;
231}
232
233static int ams_i2c_remove(struct i2c_client *client)
234{
235 if (ams_info.has_device) {
236 ams_sensor_detach();
237
238 /* Disable interrupts */
239 ams_i2c_set_irq(AMS_IRQ_ALL, 0);
240
241 /* Clear interrupts */
242 ams_i2c_clear_irq(AMS_IRQ_ALL);
243
244 printk(KERN_INFO "ams: Unloading\n");
245
246 ams_info.has_device = 0;
247 }
248
249 return 0;
250}
251
252static void ams_i2c_exit(void)
253{
254 i2c_del_driver(&ams_i2c_driver);
255}
256
257int __init ams_i2c_init(struct device_node *np)
258{
259 int result;
260
261 /* Set implementation stuff */
262 ams_info.of_node = np;
263 ams_info.exit = ams_i2c_exit;
264 ams_info.get_vendor = ams_i2c_get_vendor;
265 ams_info.get_xyz = ams_i2c_get_xyz;
266 ams_info.clear_irq = ams_i2c_clear_irq;
267 ams_info.bustype = BUS_I2C;
268
269 result = i2c_add_driver(&ams_i2c_driver);
270
271 return result;
272}
1// SPDX-License-Identifier: GPL-2.0-or-later
2/*
3 * Apple Motion Sensor driver (I2C variant)
4 *
5 * Copyright (C) 2005 Stelian Pop (stelian@popies.net)
6 * Copyright (C) 2006 Michael Hanselmann (linux-kernel@hansmi.ch)
7 *
8 * Clean room implementation based on the reverse engineered Mac OS X driver by
9 * Johannes Berg <johannes@sipsolutions.net>, documentation available at
10 * http://johannes.sipsolutions.net/PowerBook/Apple_Motion_Sensor_Specification
11 */
12
13#include <linux/module.h>
14#include <linux/types.h>
15#include <linux/errno.h>
16#include <linux/init.h>
17#include <linux/delay.h>
18
19#include "ams.h"
20
21/* AMS registers */
22#define AMS_COMMAND 0x00 /* command register */
23#define AMS_STATUS 0x01 /* status register */
24#define AMS_CTRL1 0x02 /* read control 1 (number of values) */
25#define AMS_CTRL2 0x03 /* read control 2 (offset?) */
26#define AMS_CTRL3 0x04 /* read control 3 (size of each value?) */
27#define AMS_DATA1 0x05 /* read data 1 */
28#define AMS_DATA2 0x06 /* read data 2 */
29#define AMS_DATA3 0x07 /* read data 3 */
30#define AMS_DATA4 0x08 /* read data 4 */
31#define AMS_DATAX 0x20 /* data X */
32#define AMS_DATAY 0x21 /* data Y */
33#define AMS_DATAZ 0x22 /* data Z */
34#define AMS_FREEFALL 0x24 /* freefall int control */
35#define AMS_SHOCK 0x25 /* shock int control */
36#define AMS_SENSLOW 0x26 /* sensitivity low limit */
37#define AMS_SENSHIGH 0x27 /* sensitivity high limit */
38#define AMS_CTRLX 0x28 /* control X */
39#define AMS_CTRLY 0x29 /* control Y */
40#define AMS_CTRLZ 0x2A /* control Z */
41#define AMS_UNKNOWN1 0x2B /* unknown 1 */
42#define AMS_UNKNOWN2 0x2C /* unknown 2 */
43#define AMS_UNKNOWN3 0x2D /* unknown 3 */
44#define AMS_VENDOR 0x2E /* vendor */
45
46/* AMS commands - use with the AMS_COMMAND register */
47enum ams_i2c_cmd {
48 AMS_CMD_NOOP = 0,
49 AMS_CMD_VERSION,
50 AMS_CMD_READMEM,
51 AMS_CMD_WRITEMEM,
52 AMS_CMD_ERASEMEM,
53 AMS_CMD_READEE,
54 AMS_CMD_WRITEEE,
55 AMS_CMD_RESET,
56 AMS_CMD_START,
57};
58
59static int ams_i2c_probe(struct i2c_client *client,
60 const struct i2c_device_id *id);
61static int ams_i2c_remove(struct i2c_client *client);
62
63static const struct i2c_device_id ams_id[] = {
64 { "MAC,accelerometer_1", 0 },
65 { }
66};
67MODULE_DEVICE_TABLE(i2c, ams_id);
68
69static struct i2c_driver ams_i2c_driver = {
70 .driver = {
71 .name = "ams",
72 },
73 .probe = ams_i2c_probe,
74 .remove = ams_i2c_remove,
75 .id_table = ams_id,
76};
77
78static s32 ams_i2c_read(u8 reg)
79{
80 return i2c_smbus_read_byte_data(ams_info.i2c_client, reg);
81}
82
83static int ams_i2c_write(u8 reg, u8 value)
84{
85 return i2c_smbus_write_byte_data(ams_info.i2c_client, reg, value);
86}
87
88static int ams_i2c_cmd(enum ams_i2c_cmd cmd)
89{
90 s32 result;
91 int count = 3;
92
93 ams_i2c_write(AMS_COMMAND, cmd);
94 msleep(5);
95
96 while (count--) {
97 result = ams_i2c_read(AMS_COMMAND);
98 if (result == 0 || result & 0x80)
99 return 0;
100
101 schedule_timeout_uninterruptible(HZ / 20);
102 }
103
104 return -1;
105}
106
107static void ams_i2c_set_irq(enum ams_irq reg, char enable)
108{
109 if (reg & AMS_IRQ_FREEFALL) {
110 u8 val = ams_i2c_read(AMS_CTRLX);
111 if (enable)
112 val |= 0x80;
113 else
114 val &= ~0x80;
115 ams_i2c_write(AMS_CTRLX, val);
116 }
117
118 if (reg & AMS_IRQ_SHOCK) {
119 u8 val = ams_i2c_read(AMS_CTRLY);
120 if (enable)
121 val |= 0x80;
122 else
123 val &= ~0x80;
124 ams_i2c_write(AMS_CTRLY, val);
125 }
126
127 if (reg & AMS_IRQ_GLOBAL) {
128 u8 val = ams_i2c_read(AMS_CTRLZ);
129 if (enable)
130 val |= 0x80;
131 else
132 val &= ~0x80;
133 ams_i2c_write(AMS_CTRLZ, val);
134 }
135}
136
137static void ams_i2c_clear_irq(enum ams_irq reg)
138{
139 if (reg & AMS_IRQ_FREEFALL)
140 ams_i2c_write(AMS_FREEFALL, 0);
141
142 if (reg & AMS_IRQ_SHOCK)
143 ams_i2c_write(AMS_SHOCK, 0);
144}
145
146static u8 ams_i2c_get_vendor(void)
147{
148 return ams_i2c_read(AMS_VENDOR);
149}
150
151static void ams_i2c_get_xyz(s8 *x, s8 *y, s8 *z)
152{
153 *x = ams_i2c_read(AMS_DATAX);
154 *y = ams_i2c_read(AMS_DATAY);
155 *z = ams_i2c_read(AMS_DATAZ);
156}
157
158static int ams_i2c_probe(struct i2c_client *client,
159 const struct i2c_device_id *id)
160{
161 int vmaj, vmin;
162 int result;
163
164 /* There can be only one */
165 if (unlikely(ams_info.has_device))
166 return -ENODEV;
167
168 ams_info.i2c_client = client;
169
170 if (ams_i2c_cmd(AMS_CMD_RESET)) {
171 printk(KERN_INFO "ams: Failed to reset the device\n");
172 return -ENODEV;
173 }
174
175 if (ams_i2c_cmd(AMS_CMD_START)) {
176 printk(KERN_INFO "ams: Failed to start the device\n");
177 return -ENODEV;
178 }
179
180 /* get version/vendor information */
181 ams_i2c_write(AMS_CTRL1, 0x02);
182 ams_i2c_write(AMS_CTRL2, 0x85);
183 ams_i2c_write(AMS_CTRL3, 0x01);
184
185 ams_i2c_cmd(AMS_CMD_READMEM);
186
187 vmaj = ams_i2c_read(AMS_DATA1);
188 vmin = ams_i2c_read(AMS_DATA2);
189 if (vmaj != 1 || vmin != 52) {
190 printk(KERN_INFO "ams: Incorrect device version (%d.%d)\n",
191 vmaj, vmin);
192 return -ENODEV;
193 }
194
195 ams_i2c_cmd(AMS_CMD_VERSION);
196
197 vmaj = ams_i2c_read(AMS_DATA1);
198 vmin = ams_i2c_read(AMS_DATA2);
199 if (vmaj != 0 || vmin != 1) {
200 printk(KERN_INFO "ams: Incorrect firmware version (%d.%d)\n",
201 vmaj, vmin);
202 return -ENODEV;
203 }
204
205 /* Disable interrupts */
206 ams_i2c_set_irq(AMS_IRQ_ALL, 0);
207
208 result = ams_sensor_attach();
209 if (result < 0)
210 return result;
211
212 /* Set default values */
213 ams_i2c_write(AMS_SENSLOW, 0x15);
214 ams_i2c_write(AMS_SENSHIGH, 0x60);
215 ams_i2c_write(AMS_CTRLX, 0x08);
216 ams_i2c_write(AMS_CTRLY, 0x0F);
217 ams_i2c_write(AMS_CTRLZ, 0x4F);
218 ams_i2c_write(AMS_UNKNOWN1, 0x14);
219
220 /* Clear interrupts */
221 ams_i2c_clear_irq(AMS_IRQ_ALL);
222
223 ams_info.has_device = 1;
224
225 /* Enable interrupts */
226 ams_i2c_set_irq(AMS_IRQ_ALL, 1);
227
228 printk(KERN_INFO "ams: Found I2C based motion sensor\n");
229
230 return 0;
231}
232
233static int ams_i2c_remove(struct i2c_client *client)
234{
235 if (ams_info.has_device) {
236 ams_sensor_detach();
237
238 /* Disable interrupts */
239 ams_i2c_set_irq(AMS_IRQ_ALL, 0);
240
241 /* Clear interrupts */
242 ams_i2c_clear_irq(AMS_IRQ_ALL);
243
244 printk(KERN_INFO "ams: Unloading\n");
245
246 ams_info.has_device = 0;
247 }
248
249 return 0;
250}
251
252static void ams_i2c_exit(void)
253{
254 i2c_del_driver(&ams_i2c_driver);
255}
256
257int __init ams_i2c_init(struct device_node *np)
258{
259 int result;
260
261 /* Set implementation stuff */
262 ams_info.of_node = np;
263 ams_info.exit = ams_i2c_exit;
264 ams_info.get_vendor = ams_i2c_get_vendor;
265 ams_info.get_xyz = ams_i2c_get_xyz;
266 ams_info.clear_irq = ams_i2c_clear_irq;
267 ams_info.bustype = BUS_I2C;
268
269 result = i2c_add_driver(&ams_i2c_driver);
270
271 return result;
272}