diff options
Diffstat (limited to 'drivers/input/misc/mma8450.c')
-rw-r--r-- | drivers/input/misc/mma8450.c | 256 |
1 files changed, 256 insertions, 0 deletions
diff --git a/drivers/input/misc/mma8450.c b/drivers/input/misc/mma8450.c new file mode 100644 index 000000000000..20f8f9284f02 --- /dev/null +++ b/drivers/input/misc/mma8450.c | |||
@@ -0,0 +1,256 @@ | |||
1 | /* | ||
2 | * Driver for Freescale's 3-Axis Accelerometer MMA8450 | ||
3 | * | ||
4 | * Copyright (C) 2011 Freescale Semiconductor, Inc. All Rights Reserved. | ||
5 | * | ||
6 | * This program is free software; you can redistribute it and/or modify | ||
7 | * it under the terms of the GNU General Public License as published by | ||
8 | * the Free Software Foundation; either version 2 of the License, or | ||
9 | * (at your option) any later version. | ||
10 | * | ||
11 | * This program is distributed in the hope that it will be useful, | ||
12 | * but WITHOUT ANY WARRANTY; without even the implied warranty of | ||
13 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the | ||
14 | * GNU General Public License for more details. | ||
15 | * | ||
16 | * You should have received a copy of the GNU General Public License | ||
17 | * along with this program; if not, write to the Free Software | ||
18 | * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. | ||
19 | */ | ||
20 | |||
21 | #include <linux/kernel.h> | ||
22 | #include <linux/module.h> | ||
23 | #include <linux/slab.h> | ||
24 | #include <linux/delay.h> | ||
25 | #include <linux/i2c.h> | ||
26 | #include <linux/input-polldev.h> | ||
27 | |||
28 | #define MMA8450_DRV_NAME "mma8450" | ||
29 | |||
30 | #define MODE_CHANGE_DELAY_MS 100 | ||
31 | #define POLL_INTERVAL 100 | ||
32 | #define POLL_INTERVAL_MAX 500 | ||
33 | |||
34 | /* register definitions */ | ||
35 | #define MMA8450_STATUS 0x00 | ||
36 | #define MMA8450_STATUS_ZXYDR 0x08 | ||
37 | |||
38 | #define MMA8450_OUT_X8 0x01 | ||
39 | #define MMA8450_OUT_Y8 0x02 | ||
40 | #define MMA8450_OUT_Z8 0x03 | ||
41 | |||
42 | #define MMA8450_OUT_X_LSB 0x05 | ||
43 | #define MMA8450_OUT_X_MSB 0x06 | ||
44 | #define MMA8450_OUT_Y_LSB 0x07 | ||
45 | #define MMA8450_OUT_Y_MSB 0x08 | ||
46 | #define MMA8450_OUT_Z_LSB 0x09 | ||
47 | #define MMA8450_OUT_Z_MSB 0x0a | ||
48 | |||
49 | #define MMA8450_XYZ_DATA_CFG 0x16 | ||
50 | |||
51 | #define MMA8450_CTRL_REG1 0x38 | ||
52 | #define MMA8450_CTRL_REG2 0x39 | ||
53 | |||
54 | /* mma8450 status */ | ||
55 | struct mma8450 { | ||
56 | struct i2c_client *client; | ||
57 | struct input_polled_dev *idev; | ||
58 | }; | ||
59 | |||
60 | static int mma8450_read(struct mma8450 *m, unsigned off) | ||
61 | { | ||
62 | struct i2c_client *c = m->client; | ||
63 | int ret; | ||
64 | |||
65 | ret = i2c_smbus_read_byte_data(c, off); | ||
66 | if (ret < 0) | ||
67 | dev_err(&c->dev, | ||
68 | "failed to read register 0x%02x, error %d\n", | ||
69 | off, ret); | ||
70 | |||
71 | return ret; | ||
72 | } | ||
73 | |||
74 | static int mma8450_write(struct mma8450 *m, unsigned off, u8 v) | ||
75 | { | ||
76 | struct i2c_client *c = m->client; | ||
77 | int error; | ||
78 | |||
79 | error = i2c_smbus_write_byte_data(c, off, v); | ||
80 | if (error < 0) { | ||
81 | dev_err(&c->dev, | ||
82 | "failed to write to register 0x%02x, error %d\n", | ||
83 | off, error); | ||
84 | return error; | ||
85 | } | ||
86 | |||
87 | return 0; | ||
88 | } | ||
89 | |||
90 | static int mma8450_read_xyz(struct mma8450 *m, int *x, int *y, int *z) | ||
91 | { | ||
92 | struct i2c_client *c = m->client; | ||
93 | u8 buff[6]; | ||
94 | int err; | ||
95 | |||
96 | err = i2c_smbus_read_i2c_block_data(c, MMA8450_OUT_X_LSB, 6, buff); | ||
97 | if (err < 0) { | ||
98 | dev_err(&c->dev, | ||
99 | "failed to read block data at 0x%02x, error %d\n", | ||
100 | MMA8450_OUT_X_LSB, err); | ||
101 | return err; | ||
102 | } | ||
103 | |||
104 | *x = ((buff[1] << 4) & 0xff0) | (buff[0] & 0xf); | ||
105 | *y = ((buff[3] << 4) & 0xff0) | (buff[2] & 0xf); | ||
106 | *z = ((buff[5] << 4) & 0xff0) | (buff[4] & 0xf); | ||
107 | |||
108 | return 0; | ||
109 | } | ||
110 | |||
111 | static void mma8450_poll(struct input_polled_dev *dev) | ||
112 | { | ||
113 | struct mma8450 *m = dev->private; | ||
114 | int x, y, z; | ||
115 | int ret; | ||
116 | int err; | ||
117 | |||
118 | ret = mma8450_read(m, MMA8450_STATUS); | ||
119 | if (ret < 0) | ||
120 | return; | ||
121 | |||
122 | if (!(ret & MMA8450_STATUS_ZXYDR)) | ||
123 | return; | ||
124 | |||
125 | err = mma8450_read_xyz(m, &x, &y, &z); | ||
126 | if (err) | ||
127 | return; | ||
128 | |||
129 | input_report_abs(dev->input, ABS_X, x); | ||
130 | input_report_abs(dev->input, ABS_Y, y); | ||
131 | input_report_abs(dev->input, ABS_Z, z); | ||
132 | input_sync(dev->input); | ||
133 | } | ||
134 | |||
135 | /* Initialize the MMA8450 chip */ | ||
136 | static void mma8450_open(struct input_polled_dev *dev) | ||
137 | { | ||
138 | struct mma8450 *m = dev->private; | ||
139 | int err; | ||
140 | |||
141 | /* enable all events from X/Y/Z, no FIFO */ | ||
142 | err = mma8450_write(m, MMA8450_XYZ_DATA_CFG, 0x07); | ||
143 | if (err) | ||
144 | return; | ||
145 | |||
146 | /* | ||
147 | * Sleep mode poll rate - 50Hz | ||
148 | * System output data rate - 400Hz | ||
149 | * Full scale selection - Active, +/- 2G | ||
150 | */ | ||
151 | err = mma8450_write(m, MMA8450_CTRL_REG1, 0x01); | ||
152 | if (err < 0) | ||
153 | return; | ||
154 | |||
155 | msleep(MODE_CHANGE_DELAY_MS); | ||
156 | } | ||
157 | |||
158 | static void mma8450_close(struct input_polled_dev *dev) | ||
159 | { | ||
160 | struct mma8450 *m = dev->private; | ||
161 | |||
162 | mma8450_write(m, MMA8450_CTRL_REG1, 0x00); | ||
163 | mma8450_write(m, MMA8450_CTRL_REG2, 0x01); | ||
164 | } | ||
165 | |||
166 | /* | ||
167 | * I2C init/probing/exit functions | ||
168 | */ | ||
169 | static int __devinit mma8450_probe(struct i2c_client *c, | ||
170 | const struct i2c_device_id *id) | ||
171 | { | ||
172 | struct input_polled_dev *idev; | ||
173 | struct mma8450 *m; | ||
174 | int err; | ||
175 | |||
176 | m = kzalloc(sizeof(struct mma8450), GFP_KERNEL); | ||
177 | idev = input_allocate_polled_device(); | ||
178 | if (!m || !idev) { | ||
179 | err = -ENOMEM; | ||
180 | goto err_free_mem; | ||
181 | } | ||
182 | |||
183 | m->client = c; | ||
184 | m->idev = idev; | ||
185 | |||
186 | idev->private = m; | ||
187 | idev->input->name = MMA8450_DRV_NAME; | ||
188 | idev->input->id.bustype = BUS_I2C; | ||
189 | idev->poll = mma8450_poll; | ||
190 | idev->poll_interval = POLL_INTERVAL; | ||
191 | idev->poll_interval_max = POLL_INTERVAL_MAX; | ||
192 | idev->open = mma8450_open; | ||
193 | idev->close = mma8450_close; | ||
194 | |||
195 | __set_bit(EV_ABS, idev->input->evbit); | ||
196 | input_set_abs_params(idev->input, ABS_X, -2048, 2047, 32, 32); | ||
197 | input_set_abs_params(idev->input, ABS_Y, -2048, 2047, 32, 32); | ||
198 | input_set_abs_params(idev->input, ABS_Z, -2048, 2047, 32, 32); | ||
199 | |||
200 | err = input_register_polled_device(idev); | ||
201 | if (err) { | ||
202 | dev_err(&c->dev, "failed to register polled input device\n"); | ||
203 | goto err_free_mem; | ||
204 | } | ||
205 | |||
206 | return 0; | ||
207 | |||
208 | err_free_mem: | ||
209 | input_free_polled_device(idev); | ||
210 | kfree(m); | ||
211 | return err; | ||
212 | } | ||
213 | |||
214 | static int __devexit mma8450_remove(struct i2c_client *c) | ||
215 | { | ||
216 | struct mma8450 *m = i2c_get_clientdata(c); | ||
217 | struct input_polled_dev *idev = m->idev; | ||
218 | |||
219 | input_unregister_polled_device(idev); | ||
220 | input_free_polled_device(idev); | ||
221 | kfree(m); | ||
222 | |||
223 | return 0; | ||
224 | } | ||
225 | |||
226 | static const struct i2c_device_id mma8450_id[] = { | ||
227 | { MMA8450_DRV_NAME, 0 }, | ||
228 | { }, | ||
229 | }; | ||
230 | MODULE_DEVICE_TABLE(i2c, mma8450_id); | ||
231 | |||
232 | static struct i2c_driver mma8450_driver = { | ||
233 | .driver = { | ||
234 | .name = MMA8450_DRV_NAME, | ||
235 | .owner = THIS_MODULE, | ||
236 | }, | ||
237 | .probe = mma8450_probe, | ||
238 | .remove = __devexit_p(mma8450_remove), | ||
239 | .id_table = mma8450_id, | ||
240 | }; | ||
241 | |||
242 | static int __init mma8450_init(void) | ||
243 | { | ||
244 | return i2c_add_driver(&mma8450_driver); | ||
245 | } | ||
246 | module_init(mma8450_init); | ||
247 | |||
248 | static void __exit mma8450_exit(void) | ||
249 | { | ||
250 | i2c_del_driver(&mma8450_driver); | ||
251 | } | ||
252 | module_exit(mma8450_exit); | ||
253 | |||
254 | MODULE_AUTHOR("Freescale Semiconductor, Inc."); | ||
255 | MODULE_DESCRIPTION("MMA8450 3-Axis Accelerometer Driver"); | ||
256 | MODULE_LICENSE("GPL"); | ||