2 * AD7466/7/8 AD7476/5/7/8 (A) SPI ADC driver
4 * Copyright 2010 Analog Devices Inc.
6 * Licensed under the GPL-2 or later.
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>
22 #include "../ring_generic.h"
27 static int ad7476_scan_direct(struct ad7476_state *st)
31 ret = spi_sync(st->spi, &st->msg);
35 return (st->data[0] << 8) | st->data[1];
38 static ssize_t ad7476_scan(struct device *dev,
39 struct device_attribute *attr,
42 struct iio_dev *dev_info = dev_get_drvdata(dev);
43 struct ad7476_state *st = dev_info->dev_data;
46 mutex_lock(&dev_info->mlock);
47 if (iio_ring_enabled(dev_info))
48 ret = ad7476_scan_from_ring(st);
50 ret = ad7476_scan_direct(st);
51 mutex_unlock(&dev_info->mlock);
56 return sprintf(buf, "%d\n", (ret >> st->chip_info->res_shift) &
57 RES_MASK(st->chip_info->bits));
59 static IIO_DEV_ATTR_IN_RAW(0, ad7476_scan, 0);
61 static ssize_t ad7476_show_scale(struct device *dev,
62 struct device_attribute *attr,
65 /* Driver currently only support internal vref */
66 struct iio_dev *dev_info = dev_get_drvdata(dev);
67 struct ad7476_state *st = iio_dev_get_devdata(dev_info);
68 /* Corresponds to Vref / 2^(bits) */
69 unsigned int scale_uv = (st->int_vref_mv * 1000) >> st->chip_info->bits;
71 return sprintf(buf, "%d.%d\n", scale_uv / 1000, scale_uv % 1000);
73 static IIO_DEVICE_ATTR(in_scale, S_IRUGO, ad7476_show_scale, NULL, 0);
75 static ssize_t ad7476_show_name(struct device *dev,
76 struct device_attribute *attr,
79 struct iio_dev *dev_info = dev_get_drvdata(dev);
80 struct ad7476_state *st = iio_dev_get_devdata(dev_info);
82 return sprintf(buf, "%s\n", spi_get_device_id(st->spi)->name);
84 static IIO_DEVICE_ATTR(name, S_IRUGO, ad7476_show_name, NULL, 0);
86 static struct attribute *ad7476_attributes[] = {
87 &iio_dev_attr_in0_raw.dev_attr.attr,
88 &iio_dev_attr_in_scale.dev_attr.attr,
89 &iio_dev_attr_name.dev_attr.attr,
93 static const struct attribute_group ad7476_attribute_group = {
94 .attrs = ad7476_attributes,
97 static const struct ad7476_chip_info ad7476_chip_info_tbl[] = {
102 .sign = IIO_SCAN_EL_TYPE_UNSIGNED,
108 .sign = IIO_SCAN_EL_TYPE_UNSIGNED,
114 .sign = IIO_SCAN_EL_TYPE_UNSIGNED,
120 .sign = IIO_SCAN_EL_TYPE_UNSIGNED,
126 .sign = IIO_SCAN_EL_TYPE_UNSIGNED,
132 .sign = IIO_SCAN_EL_TYPE_UNSIGNED,
138 .sign = IIO_SCAN_EL_TYPE_UNSIGNED,
145 .sign = IIO_SCAN_EL_TYPE_UNSIGNED,
149 static int __devinit ad7476_probe(struct spi_device *spi)
151 struct ad7476_platform_data *pdata = spi->dev.platform_data;
152 struct ad7476_state *st;
153 int ret, voltage_uv = 0;
155 st = kzalloc(sizeof(*st), GFP_KERNEL);
161 st->reg = regulator_get(&spi->dev, "vcc");
162 if (!IS_ERR(st->reg)) {
163 ret = regulator_enable(st->reg);
167 voltage_uv = regulator_get_voltage(st->reg);
171 &ad7476_chip_info_tbl[spi_get_device_id(spi)->driver_data];
173 if (st->chip_info->int_vref_mv)
174 st->int_vref_mv = st->chip_info->int_vref_mv;
175 else if (pdata && pdata->vref_mv)
176 st->int_vref_mv = pdata->vref_mv;
178 st->int_vref_mv = voltage_uv / 1000;
180 dev_warn(&spi->dev, "reference voltage unspecified\n");
182 spi_set_drvdata(spi, st);
184 atomic_set(&st->protect_ring, 0);
187 st->indio_dev = iio_allocate_device();
188 if (st->indio_dev == NULL) {
190 goto error_disable_reg;
193 /* Establish that the iio_dev is a child of the spi device */
194 st->indio_dev->dev.parent = &spi->dev;
195 st->indio_dev->attrs = &ad7476_attribute_group;
196 st->indio_dev->dev_data = (void *)(st);
197 st->indio_dev->driver_module = THIS_MODULE;
198 st->indio_dev->modes = INDIO_DIRECT_MODE;
200 /* Setup default message */
202 st->xfer.rx_buf = &st->data;
203 st->xfer.len = st->chip_info->storagebits / 8;
205 spi_message_init(&st->msg);
206 spi_message_add_tail(&st->xfer, &st->msg);
208 ret = ad7476_register_ring_funcs_and_init(st->indio_dev);
210 goto error_free_device;
212 ret = iio_device_register(st->indio_dev);
214 goto error_free_device;
216 ret = iio_ring_buffer_register(st->indio_dev->ring, 0);
218 goto error_cleanup_ring;
222 ad7476_ring_cleanup(st->indio_dev);
223 iio_device_unregister(st->indio_dev);
225 iio_free_device(st->indio_dev);
227 if (!IS_ERR(st->reg))
228 regulator_disable(st->reg);
230 if (!IS_ERR(st->reg))
231 regulator_put(st->reg);
237 static int ad7476_remove(struct spi_device *spi)
239 struct ad7476_state *st = spi_get_drvdata(spi);
240 struct iio_dev *indio_dev = st->indio_dev;
241 iio_ring_buffer_unregister(indio_dev->ring);
242 ad7476_ring_cleanup(indio_dev);
243 iio_device_unregister(indio_dev);
244 if (!IS_ERR(st->reg)) {
245 regulator_disable(st->reg);
246 regulator_put(st->reg);
252 static const struct spi_device_id ad7476_id[] = {
253 {"ad7466", ID_AD7466},
254 {"ad7467", ID_AD7467},
255 {"ad7468", ID_AD7468},
256 {"ad7475", ID_AD7475},
257 {"ad7476", ID_AD7476},
258 {"ad7476a", ID_AD7476},
259 {"ad7477", ID_AD7477},
260 {"ad7477a", ID_AD7477},
261 {"ad7478", ID_AD7478},
262 {"ad7478a", ID_AD7478},
263 {"ad7495", ID_AD7495},
267 static struct spi_driver ad7476_driver = {
270 .bus = &spi_bus_type,
271 .owner = THIS_MODULE,
273 .probe = ad7476_probe,
274 .remove = __devexit_p(ad7476_remove),
275 .id_table = ad7476_id,
278 static int __init ad7476_init(void)
280 return spi_register_driver(&ad7476_driver);
282 module_init(ad7476_init);
284 static void __exit ad7476_exit(void)
286 spi_unregister_driver(&ad7476_driver);
288 module_exit(ad7476_exit);
290 MODULE_AUTHOR("Michael Hennerich <hennerich@blackfin.uclinux.org>");
291 MODULE_DESCRIPTION("Analog Devices AD7475/6/7/8(A) AD7466/7/8 ADC");
292 MODULE_LICENSE("GPL v2");
293 MODULE_ALIAS("spi:ad7476");