1
2
3
4
5
6
7
8
9#include <linux/interrupt.h>
10#include <linux/workqueue.h>
11#include <linux/device.h>
12#include <linux/kernel.h>
13#include <linux/slab.h>
14#include <linux/sysfs.h>
15#include <linux/list.h>
16#include <linux/spi/spi.h>
17#include <linux/regulator/consumer.h>
18#include <linux/err.h>
19
20#include "../iio.h"
21#include "../sysfs.h"
22#include "../ring_generic.h"
23#include "adc.h"
24
25#include "ad7887.h"
26
27static int ad7887_scan_direct(struct ad7887_state *st, unsigned ch)
28{
29 int ret = spi_sync(st->spi, &st->msg[ch]);
30 if (ret)
31 return ret;
32
33 return (st->data[(ch * 2)] << 8) | st->data[(ch * 2) + 1];
34}
35
36static ssize_t ad7887_scan(struct device *dev,
37 struct device_attribute *attr,
38 char *buf)
39{
40 struct iio_dev *dev_info = dev_get_drvdata(dev);
41 struct ad7887_state *st = dev_info->dev_data;
42 struct iio_dev_attr *this_attr = to_iio_dev_attr(attr);
43 int ret;
44
45 mutex_lock(&dev_info->mlock);
46 if (iio_ring_enabled(dev_info))
47 ret = ad7887_scan_from_ring(st, 1 << this_attr->address);
48 else
49 ret = ad7887_scan_direct(st, this_attr->address);
50 mutex_unlock(&dev_info->mlock);
51
52 if (ret < 0)
53 return ret;
54
55 return sprintf(buf, "%d\n", (ret >> st->chip_info->left_shift) &
56 RES_MASK(st->chip_info->bits));
57}
58static IIO_DEV_ATTR_IN_RAW(0, ad7887_scan, 0);
59static IIO_DEV_ATTR_IN_RAW(1, ad7887_scan, 1);
60
61static ssize_t ad7887_show_scale(struct device *dev,
62 struct device_attribute *attr,
63 char *buf)
64{
65
66 struct iio_dev *dev_info = dev_get_drvdata(dev);
67 struct ad7887_state *st = iio_dev_get_devdata(dev_info);
68
69 unsigned int scale_uv = (st->int_vref_mv * 1000) >> st->chip_info->bits;
70
71 return sprintf(buf, "%d.%03d\n", scale_uv / 1000, scale_uv % 1000);
72}
73static IIO_DEVICE_ATTR(in_scale, S_IRUGO, ad7887_show_scale, NULL, 0);
74
75static ssize_t ad7887_show_name(struct device *dev,
76 struct device_attribute *attr,
77 char *buf)
78{
79 struct iio_dev *dev_info = dev_get_drvdata(dev);
80 struct ad7887_state *st = iio_dev_get_devdata(dev_info);
81
82 return sprintf(buf, "%s\n", spi_get_device_id(st->spi)->name);
83}
84static IIO_DEVICE_ATTR(name, S_IRUGO, ad7887_show_name, NULL, 0);
85
86static struct attribute *ad7887_attributes[] = {
87 &iio_dev_attr_in0_raw.dev_attr.attr,
88 &iio_dev_attr_in1_raw.dev_attr.attr,
89 &iio_dev_attr_in_scale.dev_attr.attr,
90 &iio_dev_attr_name.dev_attr.attr,
91 NULL,
92};
93
94static mode_t ad7887_attr_is_visible(struct kobject *kobj,
95 struct attribute *attr, int n)
96{
97 struct device *dev = container_of(kobj, struct device, kobj);
98 struct iio_dev *dev_info = dev_get_drvdata(dev);
99 struct ad7887_state *st = iio_dev_get_devdata(dev_info);
100
101 mode_t mode = attr->mode;
102
103 if ((attr == &iio_dev_attr_in1_raw.dev_attr.attr) && !st->en_dual)
104 mode = 0;
105
106 return mode;
107}
108
109static const struct attribute_group ad7887_attribute_group = {
110 .attrs = ad7887_attributes,
111 .is_visible = ad7887_attr_is_visible,
112};
113
114static const struct ad7887_chip_info ad7887_chip_info_tbl[] = {
115
116
117
118 [ID_AD7887] = {
119 .bits = 12,
120 .storagebits = 16,
121 .left_shift = 0,
122 .sign = IIO_SCAN_EL_TYPE_UNSIGNED,
123 .int_vref_mv = 2500,
124 },
125};
126
127static int __devinit ad7887_probe(struct spi_device *spi)
128{
129 struct ad7887_platform_data *pdata = spi->dev.platform_data;
130 struct ad7887_state *st;
131 int ret, voltage_uv = 0;
132
133 st = kzalloc(sizeof(*st), GFP_KERNEL);
134 if (st == NULL) {
135 ret = -ENOMEM;
136 goto error_ret;
137 }
138
139 st->reg = regulator_get(&spi->dev, "vcc");
140 if (!IS_ERR(st->reg)) {
141 ret = regulator_enable(st->reg);
142 if (ret)
143 goto error_put_reg;
144
145 voltage_uv = regulator_get_voltage(st->reg);
146 }
147
148 st->chip_info =
149 &ad7887_chip_info_tbl[spi_get_device_id(spi)->driver_data];
150
151 spi_set_drvdata(spi, st);
152
153 atomic_set(&st->protect_ring, 0);
154 st->spi = spi;
155
156 st->indio_dev = iio_allocate_device();
157 if (st->indio_dev == NULL) {
158 ret = -ENOMEM;
159 goto error_disable_reg;
160 }
161
162
163 st->indio_dev->dev.parent = &spi->dev;
164 st->indio_dev->attrs = &ad7887_attribute_group;
165 st->indio_dev->dev_data = (void *)(st);
166 st->indio_dev->driver_module = THIS_MODULE;
167 st->indio_dev->modes = INDIO_DIRECT_MODE;
168
169
170
171 st->tx_cmd_buf[0] = AD7887_CH_AIN0 | AD7887_PM_MODE4 |
172 ((pdata && pdata->use_onchip_ref) ?
173 0 : AD7887_REF_DIS);
174
175 st->xfer[0].rx_buf = &st->data[0];
176 st->xfer[0].tx_buf = &st->tx_cmd_buf[0];
177 st->xfer[0].len = 2;
178
179 spi_message_init(&st->msg[AD7887_CH0]);
180 spi_message_add_tail(&st->xfer[0], &st->msg[AD7887_CH0]);
181
182 if (pdata && pdata->en_dual) {
183 st->tx_cmd_buf[0] |= AD7887_DUAL | AD7887_REF_DIS;
184
185 st->tx_cmd_buf[2] = AD7887_CH_AIN1 | AD7887_DUAL |
186 AD7887_REF_DIS | AD7887_PM_MODE4;
187 st->tx_cmd_buf[4] = AD7887_CH_AIN0 | AD7887_DUAL |
188 AD7887_REF_DIS | AD7887_PM_MODE4;
189 st->tx_cmd_buf[6] = AD7887_CH_AIN1 | AD7887_DUAL |
190 AD7887_REF_DIS | AD7887_PM_MODE4;
191
192 st->xfer[1].rx_buf = &st->data[0];
193 st->xfer[1].tx_buf = &st->tx_cmd_buf[2];
194 st->xfer[1].len = 2;
195
196 st->xfer[2].rx_buf = &st->data[2];
197 st->xfer[2].tx_buf = &st->tx_cmd_buf[4];
198 st->xfer[2].len = 2;
199
200 spi_message_init(&st->msg[AD7887_CH0_CH1]);
201 spi_message_add_tail(&st->xfer[1], &st->msg[AD7887_CH0_CH1]);
202 spi_message_add_tail(&st->xfer[2], &st->msg[AD7887_CH0_CH1]);
203
204 st->xfer[3].rx_buf = &st->data[0];
205 st->xfer[3].tx_buf = &st->tx_cmd_buf[6];
206 st->xfer[3].len = 2;
207
208 spi_message_init(&st->msg[AD7887_CH1]);
209 spi_message_add_tail(&st->xfer[3], &st->msg[AD7887_CH1]);
210
211 st->en_dual = true;
212
213 if (pdata && pdata->vref_mv)
214 st->int_vref_mv = pdata->vref_mv;
215 else if (voltage_uv)
216 st->int_vref_mv = voltage_uv / 1000;
217 else
218 dev_warn(&spi->dev, "reference voltage unspecified\n");
219
220 } else {
221 if (pdata && pdata->vref_mv)
222 st->int_vref_mv = pdata->vref_mv;
223 else if (pdata && pdata->use_onchip_ref)
224 st->int_vref_mv = st->chip_info->int_vref_mv;
225 else
226 dev_warn(&spi->dev, "reference voltage unspecified\n");
227 }
228
229
230 ret = ad7887_register_ring_funcs_and_init(st->indio_dev);
231 if (ret)
232 goto error_free_device;
233
234 ret = iio_device_register(st->indio_dev);
235 if (ret)
236 goto error_free_device;
237
238 ret = iio_ring_buffer_register(st->indio_dev->ring, 0);
239 if (ret)
240 goto error_cleanup_ring;
241 return 0;
242
243error_cleanup_ring:
244 ad7887_ring_cleanup(st->indio_dev);
245 iio_device_unregister(st->indio_dev);
246error_free_device:
247 iio_free_device(st->indio_dev);
248error_disable_reg:
249 if (!IS_ERR(st->reg))
250 regulator_disable(st->reg);
251error_put_reg:
252 if (!IS_ERR(st->reg))
253 regulator_put(st->reg);
254 kfree(st);
255error_ret:
256 return ret;
257}
258
259static int ad7887_remove(struct spi_device *spi)
260{
261 struct ad7887_state *st = spi_get_drvdata(spi);
262 struct iio_dev *indio_dev = st->indio_dev;
263 iio_ring_buffer_unregister(indio_dev->ring);
264 ad7887_ring_cleanup(indio_dev);
265 iio_device_unregister(indio_dev);
266 if (!IS_ERR(st->reg)) {
267 regulator_disable(st->reg);
268 regulator_put(st->reg);
269 }
270 kfree(st);
271 return 0;
272}
273
274static const struct spi_device_id ad7887_id[] = {
275 {"ad7887", ID_AD7887},
276 {}
277};
278
279static struct spi_driver ad7887_driver = {
280 .driver = {
281 .name = "ad7887",
282 .bus = &spi_bus_type,
283 .owner = THIS_MODULE,
284 },
285 .probe = ad7887_probe,
286 .remove = __devexit_p(ad7887_remove),
287 .id_table = ad7887_id,
288};
289
290static int __init ad7887_init(void)
291{
292 return spi_register_driver(&ad7887_driver);
293}
294module_init(ad7887_init);
295
296static void __exit ad7887_exit(void)
297{
298 spi_unregister_driver(&ad7887_driver);
299}
300module_exit(ad7887_exit);
301
302MODULE_AUTHOR("Michael Hennerich <hennerich@blackfin.uclinux.org>");
303MODULE_DESCRIPTION("Analog Devices AD7887 ADC");
304MODULE_LICENSE("GPL v2");
305MODULE_ALIAS("spi:ad7887");
306
