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13#include <linux/err.h>
14#include <linux/i2c.h>
15#include <linux/of_irq.h>
16#include <linux/delay.h>
17#include <linux/module.h>
18#include <linux/bitops.h>
19#include <linux/iio/iio.h>
20#include <linux/iio/sysfs.h>
21#include <linux/iio/buffer.h>
22#include <linux/iio/trigger_consumer.h>
23#include <linux/iio/triggered_buffer.h>
24
25
26#define MB1232_RANGE_COMMAND 0x51
27#define MB1232_ADDR_UNLOCK_1 0xAA
28#define MB1232_ADDR_UNLOCK_2 0xA5
29
30struct mb1232_data {
31 struct i2c_client *client;
32
33 struct mutex lock;
34
35
36
37
38
39
40
41 struct completion ranging;
42 int irqnr;
43
44 struct {
45 s16 distance;
46 s64 ts __aligned(8);
47 } scan;
48};
49
50static irqreturn_t mb1232_handle_irq(int irq, void *dev_id)
51{
52 struct iio_dev *indio_dev = dev_id;
53 struct mb1232_data *data = iio_priv(indio_dev);
54
55 complete(&data->ranging);
56
57 return IRQ_HANDLED;
58}
59
60static s16 mb1232_read_distance(struct mb1232_data *data)
61{
62 struct i2c_client *client = data->client;
63 int ret;
64 s16 distance;
65 __be16 buf;
66
67 mutex_lock(&data->lock);
68
69 reinit_completion(&data->ranging);
70
71 ret = i2c_smbus_write_byte(client, MB1232_RANGE_COMMAND);
72 if (ret < 0) {
73 dev_err(&client->dev, "write command - err: %d\n", ret);
74 goto error_unlock;
75 }
76
77 if (data->irqnr >= 0) {
78
79 ret = wait_for_completion_killable_timeout(&data->ranging,
80 HZ/10);
81 if (ret < 0)
82 goto error_unlock;
83 else if (ret == 0) {
84 ret = -ETIMEDOUT;
85 goto error_unlock;
86 }
87 } else {
88
89 msleep(15);
90 }
91
92 ret = i2c_master_recv(client, (char *)&buf, sizeof(buf));
93 if (ret < 0) {
94 dev_err(&client->dev, "i2c_master_recv: ret=%d\n", ret);
95 goto error_unlock;
96 }
97
98 distance = __be16_to_cpu(buf);
99
100 if (distance < 0) {
101 dev_err(&client->dev, "distance=%d\n", distance);
102 ret = -EINVAL;
103 goto error_unlock;
104 }
105
106 mutex_unlock(&data->lock);
107
108 return distance;
109
110error_unlock:
111 mutex_unlock(&data->lock);
112
113 return ret;
114}
115
116static irqreturn_t mb1232_trigger_handler(int irq, void *p)
117{
118 struct iio_poll_func *pf = p;
119 struct iio_dev *indio_dev = pf->indio_dev;
120 struct mb1232_data *data = iio_priv(indio_dev);
121
122 data->scan.distance = mb1232_read_distance(data);
123 if (data->scan.distance < 0)
124 goto err;
125
126 iio_push_to_buffers_with_timestamp(indio_dev, &data->scan,
127 pf->timestamp);
128
129err:
130 iio_trigger_notify_done(indio_dev->trig);
131 return IRQ_HANDLED;
132}
133
134static int mb1232_read_raw(struct iio_dev *indio_dev,
135 struct iio_chan_spec const *channel, int *val,
136 int *val2, long mask)
137{
138 struct mb1232_data *data = iio_priv(indio_dev);
139 int ret;
140
141 if (channel->type != IIO_DISTANCE)
142 return -EINVAL;
143
144 switch (mask) {
145 case IIO_CHAN_INFO_RAW:
146 ret = mb1232_read_distance(data);
147 if (ret < 0)
148 return ret;
149 *val = ret;
150 return IIO_VAL_INT;
151 case IIO_CHAN_INFO_SCALE:
152
153 *val = 0;
154 *val2 = 10000;
155 return IIO_VAL_INT_PLUS_MICRO;
156 default:
157 return -EINVAL;
158 }
159}
160
161static const struct iio_chan_spec mb1232_channels[] = {
162 {
163 .type = IIO_DISTANCE,
164 .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |
165 BIT(IIO_CHAN_INFO_SCALE),
166 .scan_index = 0,
167 .scan_type = {
168 .sign = 's',
169 .realbits = 16,
170 .storagebits = 16,
171 .endianness = IIO_CPU,
172 },
173 },
174 IIO_CHAN_SOFT_TIMESTAMP(1),
175};
176
177static const struct iio_info mb1232_info = {
178 .read_raw = mb1232_read_raw,
179};
180
181static int mb1232_probe(struct i2c_client *client,
182 const struct i2c_device_id *id)
183{
184 struct iio_dev *indio_dev;
185 struct mb1232_data *data;
186 int ret;
187 struct device *dev = &client->dev;
188
189 if (!i2c_check_functionality(client->adapter,
190 I2C_FUNC_SMBUS_READ_BYTE |
191 I2C_FUNC_SMBUS_WRITE_BYTE))
192 return -ENODEV;
193
194 indio_dev = devm_iio_device_alloc(dev, sizeof(*data));
195 if (!indio_dev)
196 return -ENOMEM;
197
198 data = iio_priv(indio_dev);
199 i2c_set_clientdata(client, indio_dev);
200 data->client = client;
201
202 indio_dev->info = &mb1232_info;
203 indio_dev->name = id->name;
204 indio_dev->modes = INDIO_DIRECT_MODE;
205 indio_dev->channels = mb1232_channels;
206 indio_dev->num_channels = ARRAY_SIZE(mb1232_channels);
207
208 mutex_init(&data->lock);
209
210 init_completion(&data->ranging);
211
212 data->irqnr = irq_of_parse_and_map(dev->of_node, 0);
213 if (data->irqnr <= 0) {
214
215 data->irqnr = -1;
216 } else {
217 ret = devm_request_irq(dev, data->irqnr, mb1232_handle_irq,
218 IRQF_TRIGGER_FALLING, id->name, indio_dev);
219 if (ret < 0) {
220 dev_err(dev, "request_irq: %d\n", ret);
221 return ret;
222 }
223 }
224
225 ret = devm_iio_triggered_buffer_setup(dev, indio_dev,
226 iio_pollfunc_store_time, mb1232_trigger_handler, NULL);
227 if (ret < 0) {
228 dev_err(dev, "setup of iio triggered buffer failed\n");
229 return ret;
230 }
231
232 return devm_iio_device_register(dev, indio_dev);
233}
234
235static const struct of_device_id of_mb1232_match[] = {
236 { .compatible = "maxbotix,mb1202", },
237 { .compatible = "maxbotix,mb1212", },
238 { .compatible = "maxbotix,mb1222", },
239 { .compatible = "maxbotix,mb1232", },
240 { .compatible = "maxbotix,mb1242", },
241 { .compatible = "maxbotix,mb7040", },
242 { .compatible = "maxbotix,mb7137", },
243 {},
244};
245
246MODULE_DEVICE_TABLE(of, of_mb1232_match);
247
248static const struct i2c_device_id mb1232_id[] = {
249 { "maxbotix-mb1202", },
250 { "maxbotix-mb1212", },
251 { "maxbotix-mb1222", },
252 { "maxbotix-mb1232", },
253 { "maxbotix-mb1242", },
254 { "maxbotix-mb7040", },
255 { "maxbotix-mb7137", },
256 { }
257};
258MODULE_DEVICE_TABLE(i2c, mb1232_id);
259
260static struct i2c_driver mb1232_driver = {
261 .driver = {
262 .name = "maxbotix-mb1232",
263 .of_match_table = of_mb1232_match,
264 },
265 .probe = mb1232_probe,
266 .id_table = mb1232_id,
267};
268module_i2c_driver(mb1232_driver);
269
270MODULE_AUTHOR("Andreas Klinger <ak@it-klinger.de>");
271MODULE_DESCRIPTION("Maxbotix I2CXL-MaxSonar i2c ultrasonic ranger driver");
272MODULE_LICENSE("GPL");
273
