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/device.h>
10 #include <linux/kernel.h>
11 #include <linux/slab.h>
12 #include <linux/sysfs.h>
13 #include <linux/spi/spi.h>
14 #include <linux/regulator/consumer.h>
15 #include <linux/err.h>
16 #include <linux/module.h>
20 #include "../buffer.h"
24 static int ad7476_scan_direct(struct ad7476_state
*st
)
28 ret
= spi_sync(st
->spi
, &st
->msg
);
32 return (st
->data
[0] << 8) | st
->data
[1];
35 static int ad7476_read_raw(struct iio_dev
*indio_dev
,
36 struct iio_chan_spec
const *chan
,
42 struct ad7476_state
*st
= iio_priv(indio_dev
);
43 unsigned int scale_uv
;
47 mutex_lock(&indio_dev
->mlock
);
48 if (iio_buffer_enabled(indio_dev
))
49 ret
= ad7476_scan_from_ring(indio_dev
);
51 ret
= ad7476_scan_direct(st
);
52 mutex_unlock(&indio_dev
->mlock
);
56 *val
= (ret
>> st
->chip_info
->channel
[0].scan_type
.shift
) &
57 RES_MASK(st
->chip_info
->channel
[0].scan_type
.realbits
);
59 case IIO_CHAN_INFO_SCALE_SHARED
:
60 scale_uv
= (st
->int_vref_mv
* 1000)
61 >> st
->chip_info
->channel
[0].scan_type
.realbits
;
63 *val2
= (scale_uv
%1000)*1000;
64 return IIO_VAL_INT_PLUS_MICRO
;
69 static const struct ad7476_chip_info ad7476_chip_info_tbl
[] = {
71 .channel
[0] = IIO_CHAN(IIO_VOLTAGE
, 0, 1, 0, NULL
, 0, 0,
72 (1 << IIO_CHAN_INFO_SCALE_SHARED
),
73 0, 0, IIO_ST('u', 12, 16, 0), 0),
74 .channel
[1] = IIO_CHAN_SOFT_TIMESTAMP(1),
77 .channel
[0] = IIO_CHAN(IIO_VOLTAGE
, 0, 1, 0, NULL
, 0, 0,
78 (1 << IIO_CHAN_INFO_SCALE_SHARED
),
79 0, 0, IIO_ST('u', 10, 16, 2), 0),
80 .channel
[1] = IIO_CHAN_SOFT_TIMESTAMP(1),
83 .channel
[0] = IIO_CHAN(IIO_VOLTAGE
, 0, 1 , 0, NULL
, 0, 0,
84 (1 << IIO_CHAN_INFO_SCALE_SHARED
),
85 0, 0, IIO_ST('u', 8, 16, 4), 0),
86 .channel
[1] = IIO_CHAN_SOFT_TIMESTAMP(1),
89 .channel
[0] = IIO_CHAN(IIO_VOLTAGE
, 0, 1, 0, NULL
, 0, 0,
90 (1 << IIO_CHAN_INFO_SCALE_SHARED
),
91 0, 0, IIO_ST('u', 12, 16, 0), 0),
92 .channel
[1] = IIO_CHAN_SOFT_TIMESTAMP(1),
95 .channel
[0] = IIO_CHAN(IIO_VOLTAGE
, 0, 1, 0, NULL
, 0, 0,
96 (1 << IIO_CHAN_INFO_SCALE_SHARED
),
97 0, 0, IIO_ST('u', 12, 16, 0), 0),
98 .channel
[1] = IIO_CHAN_SOFT_TIMESTAMP(1),
101 .channel
[0] = IIO_CHAN(IIO_VOLTAGE
, 0, 1, 0, NULL
, 0, 0,
102 (1 << IIO_CHAN_INFO_SCALE_SHARED
),
103 0, 0, IIO_ST('u', 10, 16, 2), 0),
104 .channel
[1] = IIO_CHAN_SOFT_TIMESTAMP(1),
107 .channel
[0] = IIO_CHAN(IIO_VOLTAGE
, 0, 1, 0, NULL
, 0, 0,
108 (1 << IIO_CHAN_INFO_SCALE_SHARED
),
109 0, 0, IIO_ST('u', 8, 16, 4), 0),
110 .channel
[1] = IIO_CHAN_SOFT_TIMESTAMP(1),
113 .channel
[0] = IIO_CHAN(IIO_VOLTAGE
, 0, 1, 0, NULL
, 0, 0,
114 (1 << IIO_CHAN_INFO_SCALE_SHARED
),
115 0, 0, IIO_ST('u', 12, 16, 0), 0),
116 .channel
[1] = IIO_CHAN_SOFT_TIMESTAMP(1),
121 static const struct iio_info ad7476_info
= {
122 .driver_module
= THIS_MODULE
,
123 .read_raw
= &ad7476_read_raw
,
126 static int __devinit
ad7476_probe(struct spi_device
*spi
)
128 struct ad7476_platform_data
*pdata
= spi
->dev
.platform_data
;
129 struct ad7476_state
*st
;
130 struct iio_dev
*indio_dev
;
131 int ret
, voltage_uv
= 0;
133 indio_dev
= iio_allocate_device(sizeof(*st
));
134 if (indio_dev
== NULL
) {
138 st
= iio_priv(indio_dev
);
139 st
->reg
= regulator_get(&spi
->dev
, "vcc");
140 if (!IS_ERR(st
->reg
)) {
141 ret
= regulator_enable(st
->reg
);
145 voltage_uv
= regulator_get_voltage(st
->reg
);
148 &ad7476_chip_info_tbl
[spi_get_device_id(spi
)->driver_data
];
150 if (st
->chip_info
->int_vref_mv
)
151 st
->int_vref_mv
= st
->chip_info
->int_vref_mv
;
152 else if (pdata
&& pdata
->vref_mv
)
153 st
->int_vref_mv
= pdata
->vref_mv
;
155 st
->int_vref_mv
= voltage_uv
/ 1000;
157 dev_warn(&spi
->dev
, "reference voltage unspecified\n");
159 spi_set_drvdata(spi
, indio_dev
);
163 /* Establish that the iio_dev is a child of the spi device */
164 indio_dev
->dev
.parent
= &spi
->dev
;
165 indio_dev
->name
= spi_get_device_id(spi
)->name
;
166 indio_dev
->modes
= INDIO_DIRECT_MODE
;
167 indio_dev
->channels
= st
->chip_info
->channel
;
168 indio_dev
->num_channels
= 2;
169 indio_dev
->info
= &ad7476_info
;
170 /* Setup default message */
172 st
->xfer
.rx_buf
= &st
->data
;
173 st
->xfer
.len
= st
->chip_info
->channel
[0].scan_type
.storagebits
/ 8;
175 spi_message_init(&st
->msg
);
176 spi_message_add_tail(&st
->xfer
, &st
->msg
);
178 ret
= ad7476_register_ring_funcs_and_init(indio_dev
);
180 goto error_disable_reg
;
182 ret
= iio_buffer_register(indio_dev
,
183 st
->chip_info
->channel
,
184 ARRAY_SIZE(st
->chip_info
->channel
));
186 goto error_cleanup_ring
;
188 ret
= iio_device_register(indio_dev
);
190 goto error_ring_unregister
;
193 error_ring_unregister
:
194 iio_buffer_unregister(indio_dev
);
196 ad7476_ring_cleanup(indio_dev
);
198 if (!IS_ERR(st
->reg
))
199 regulator_disable(st
->reg
);
201 if (!IS_ERR(st
->reg
))
202 regulator_put(st
->reg
);
203 iio_free_device(indio_dev
);
209 static int ad7476_remove(struct spi_device
*spi
)
211 struct iio_dev
*indio_dev
= spi_get_drvdata(spi
);
212 struct ad7476_state
*st
= iio_priv(indio_dev
);
214 iio_device_unregister(indio_dev
);
215 iio_buffer_unregister(indio_dev
);
216 ad7476_ring_cleanup(indio_dev
);
217 if (!IS_ERR(st
->reg
)) {
218 regulator_disable(st
->reg
);
219 regulator_put(st
->reg
);
221 iio_free_device(indio_dev
);
226 static const struct spi_device_id ad7476_id
[] = {
227 {"ad7466", ID_AD7466
},
228 {"ad7467", ID_AD7467
},
229 {"ad7468", ID_AD7468
},
230 {"ad7475", ID_AD7475
},
231 {"ad7476", ID_AD7476
},
232 {"ad7476a", ID_AD7476
},
233 {"ad7477", ID_AD7477
},
234 {"ad7477a", ID_AD7477
},
235 {"ad7478", ID_AD7478
},
236 {"ad7478a", ID_AD7478
},
237 {"ad7495", ID_AD7495
},
241 static struct spi_driver ad7476_driver
= {
244 .bus
= &spi_bus_type
,
245 .owner
= THIS_MODULE
,
247 .probe
= ad7476_probe
,
248 .remove
= __devexit_p(ad7476_remove
),
249 .id_table
= ad7476_id
,
252 static int __init
ad7476_init(void)
254 return spi_register_driver(&ad7476_driver
);
256 module_init(ad7476_init
);
258 static void __exit
ad7476_exit(void)
260 spi_unregister_driver(&ad7476_driver
);
262 module_exit(ad7476_exit
);
264 MODULE_AUTHOR("Michael Hennerich <hennerich@blackfin.uclinux.org>");
265 MODULE_DESCRIPTION("Analog Devices AD7475/6/7/8(A) AD7466/7/8 ADC");
266 MODULE_LICENSE("GPL v2");
267 MODULE_ALIAS("spi:ad7476");