Michael Hennerich | 2b4756a | 2010-11-22 14:35:32 +0100 | [diff] [blame] | 1 | /* |
| 2 | * AD7887 SPI ADC driver |
| 3 | * |
Michael Hennerich | 596d060 | 2011-05-18 14:41:50 +0100 | [diff] [blame] | 4 | * Copyright 2010-2011 Analog Devices Inc. |
Michael Hennerich | 2b4756a | 2010-11-22 14:35:32 +0100 | [diff] [blame] | 5 | * |
Michael Hennerich | 596d060 | 2011-05-18 14:41:50 +0100 | [diff] [blame] | 6 | * Licensed under the GPL-2. |
Michael Hennerich | 2b4756a | 2010-11-22 14:35:32 +0100 | [diff] [blame] | 7 | */ |
| 8 | |
Michael Hennerich | 2b4756a | 2010-11-22 14:35:32 +0100 | [diff] [blame] | 9 | #include <linux/device.h> |
| 10 | #include <linux/kernel.h> |
| 11 | #include <linux/slab.h> |
| 12 | #include <linux/sysfs.h> |
Michael Hennerich | 2b4756a | 2010-11-22 14:35:32 +0100 | [diff] [blame] | 13 | #include <linux/spi/spi.h> |
| 14 | #include <linux/regulator/consumer.h> |
| 15 | #include <linux/err.h> |
Paul Gortmaker | 99c9785 | 2011-07-03 15:49:50 -0400 | [diff] [blame] | 16 | #include <linux/module.h> |
Michael Hennerich | 2b4756a | 2010-11-22 14:35:32 +0100 | [diff] [blame] | 17 | |
| 18 | #include "../iio.h" |
| 19 | #include "../sysfs.h" |
Jonathan Cameron | af5046a | 2011-10-26 17:41:32 +0100 | [diff] [blame^] | 20 | #include "../buffer.h" |
Jonathan Cameron | cdf3870 | 2011-08-12 17:08:43 +0100 | [diff] [blame] | 21 | |
Michael Hennerich | 2b4756a | 2010-11-22 14:35:32 +0100 | [diff] [blame] | 22 | |
| 23 | #include "ad7887.h" |
| 24 | |
| 25 | static int ad7887_scan_direct(struct ad7887_state *st, unsigned ch) |
| 26 | { |
| 27 | int ret = spi_sync(st->spi, &st->msg[ch]); |
| 28 | if (ret) |
| 29 | return ret; |
| 30 | |
| 31 | return (st->data[(ch * 2)] << 8) | st->data[(ch * 2) + 1]; |
| 32 | } |
| 33 | |
Jonathan Cameron | 84f79ec | 2011-10-06 17:14:37 +0100 | [diff] [blame] | 34 | static int ad7887_read_raw(struct iio_dev *indio_dev, |
Michael Hennerich | 596d060 | 2011-05-18 14:41:50 +0100 | [diff] [blame] | 35 | struct iio_chan_spec const *chan, |
| 36 | int *val, |
| 37 | int *val2, |
| 38 | long m) |
Michael Hennerich | 2b4756a | 2010-11-22 14:35:32 +0100 | [diff] [blame] | 39 | { |
Michael Hennerich | 2b4756a | 2010-11-22 14:35:32 +0100 | [diff] [blame] | 40 | int ret; |
Jonathan Cameron | 84f79ec | 2011-10-06 17:14:37 +0100 | [diff] [blame] | 41 | struct ad7887_state *st = iio_priv(indio_dev); |
Michael Hennerich | 596d060 | 2011-05-18 14:41:50 +0100 | [diff] [blame] | 42 | unsigned int scale_uv; |
Michael Hennerich | 2b4756a | 2010-11-22 14:35:32 +0100 | [diff] [blame] | 43 | |
Michael Hennerich | 596d060 | 2011-05-18 14:41:50 +0100 | [diff] [blame] | 44 | switch (m) { |
| 45 | case 0: |
Jonathan Cameron | 84f79ec | 2011-10-06 17:14:37 +0100 | [diff] [blame] | 46 | mutex_lock(&indio_dev->mlock); |
| 47 | if (iio_buffer_enabled(indio_dev)) |
Michael Hennerich | 596d060 | 2011-05-18 14:41:50 +0100 | [diff] [blame] | 48 | ret = ad7887_scan_from_ring(st, 1 << chan->address); |
| 49 | else |
| 50 | ret = ad7887_scan_direct(st, chan->address); |
Jonathan Cameron | 84f79ec | 2011-10-06 17:14:37 +0100 | [diff] [blame] | 51 | mutex_unlock(&indio_dev->mlock); |
Michael Hennerich | 2b4756a | 2010-11-22 14:35:32 +0100 | [diff] [blame] | 52 | |
Michael Hennerich | 596d060 | 2011-05-18 14:41:50 +0100 | [diff] [blame] | 53 | if (ret < 0) |
| 54 | return ret; |
| 55 | *val = (ret >> st->chip_info->channel[0].scan_type.shift) & |
| 56 | RES_MASK(st->chip_info->channel[0].scan_type.realbits); |
| 57 | return IIO_VAL_INT; |
| 58 | case (1 << IIO_CHAN_INFO_SCALE_SHARED): |
| 59 | scale_uv = (st->int_vref_mv * 1000) |
| 60 | >> st->chip_info->channel[0].scan_type.realbits; |
| 61 | *val = scale_uv/1000; |
| 62 | *val2 = (scale_uv%1000)*1000; |
| 63 | return IIO_VAL_INT_PLUS_MICRO; |
| 64 | } |
| 65 | return -EINVAL; |
Michael Hennerich | 2b4756a | 2010-11-22 14:35:32 +0100 | [diff] [blame] | 66 | } |
| 67 | |
Michael Hennerich | 2b4756a | 2010-11-22 14:35:32 +0100 | [diff] [blame] | 68 | |
| 69 | static const struct ad7887_chip_info ad7887_chip_info_tbl[] = { |
| 70 | /* |
| 71 | * More devices added in future |
| 72 | */ |
| 73 | [ID_AD7887] = { |
Jonathan Cameron | 31bf47d | 2011-09-30 10:05:44 +0100 | [diff] [blame] | 74 | .channel[0] = { |
| 75 | .type = IIO_VOLTAGE, |
| 76 | .indexed = 1, |
| 77 | .channel = 1, |
| 78 | .info_mask = (1 << IIO_CHAN_INFO_SCALE_SHARED), |
| 79 | .address = 1, |
| 80 | .scan_index = 1, |
| 81 | .scan_type = IIO_ST('u', 12, 16, 0), |
| 82 | }, |
| 83 | .channel[1] = { |
| 84 | .type = IIO_VOLTAGE, |
| 85 | .indexed = 1, |
| 86 | .channel = 0, |
| 87 | .info_mask = (1 << IIO_CHAN_INFO_SCALE_SHARED), |
| 88 | .address = 0, |
| 89 | .scan_index = 0, |
| 90 | .scan_type = IIO_ST('u', 12, 16, 0), |
| 91 | }, |
Michael Hennerich | 596d060 | 2011-05-18 14:41:50 +0100 | [diff] [blame] | 92 | .channel[2] = IIO_CHAN_SOFT_TIMESTAMP(2), |
Michael Hennerich | 2b4756a | 2010-11-22 14:35:32 +0100 | [diff] [blame] | 93 | .int_vref_mv = 2500, |
| 94 | }, |
| 95 | }; |
| 96 | |
Jonathan Cameron | 6fe8135 | 2011-05-18 14:42:37 +0100 | [diff] [blame] | 97 | static const struct iio_info ad7887_info = { |
| 98 | .read_raw = &ad7887_read_raw, |
| 99 | .driver_module = THIS_MODULE, |
| 100 | }; |
| 101 | |
Michael Hennerich | 2b4756a | 2010-11-22 14:35:32 +0100 | [diff] [blame] | 102 | static int __devinit ad7887_probe(struct spi_device *spi) |
| 103 | { |
| 104 | struct ad7887_platform_data *pdata = spi->dev.platform_data; |
| 105 | struct ad7887_state *st; |
Jonathan Cameron | 26d25ae | 2011-09-02 17:14:40 +0100 | [diff] [blame] | 106 | int ret, voltage_uv = 0; |
Michael Hennerich | f39e086 | 2011-05-18 14:41:51 +0100 | [diff] [blame] | 107 | struct iio_dev *indio_dev = iio_allocate_device(sizeof(*st)); |
Michael Hennerich | 2b4756a | 2010-11-22 14:35:32 +0100 | [diff] [blame] | 108 | |
Michael Hennerich | f39e086 | 2011-05-18 14:41:51 +0100 | [diff] [blame] | 109 | if (indio_dev == NULL) |
| 110 | return -ENOMEM; |
| 111 | |
| 112 | st = iio_priv(indio_dev); |
Michael Hennerich | 2b4756a | 2010-11-22 14:35:32 +0100 | [diff] [blame] | 113 | |
| 114 | st->reg = regulator_get(&spi->dev, "vcc"); |
| 115 | if (!IS_ERR(st->reg)) { |
| 116 | ret = regulator_enable(st->reg); |
| 117 | if (ret) |
| 118 | goto error_put_reg; |
| 119 | |
| 120 | voltage_uv = regulator_get_voltage(st->reg); |
| 121 | } |
| 122 | |
| 123 | st->chip_info = |
| 124 | &ad7887_chip_info_tbl[spi_get_device_id(spi)->driver_data]; |
| 125 | |
Michael Hennerich | f39e086 | 2011-05-18 14:41:51 +0100 | [diff] [blame] | 126 | spi_set_drvdata(spi, indio_dev); |
Michael Hennerich | 2b4756a | 2010-11-22 14:35:32 +0100 | [diff] [blame] | 127 | st->spi = spi; |
| 128 | |
Michael Hennerich | 2b4756a | 2010-11-22 14:35:32 +0100 | [diff] [blame] | 129 | /* Estabilish that the iio_dev is a child of the spi device */ |
Michael Hennerich | f39e086 | 2011-05-18 14:41:51 +0100 | [diff] [blame] | 130 | indio_dev->dev.parent = &spi->dev; |
| 131 | indio_dev->name = spi_get_device_id(spi)->name; |
Jonathan Cameron | 6fe8135 | 2011-05-18 14:42:37 +0100 | [diff] [blame] | 132 | indio_dev->info = &ad7887_info; |
Michael Hennerich | f39e086 | 2011-05-18 14:41:51 +0100 | [diff] [blame] | 133 | indio_dev->modes = INDIO_DIRECT_MODE; |
Michael Hennerich | 2b4756a | 2010-11-22 14:35:32 +0100 | [diff] [blame] | 134 | |
| 135 | /* Setup default message */ |
| 136 | |
| 137 | st->tx_cmd_buf[0] = AD7887_CH_AIN0 | AD7887_PM_MODE4 | |
| 138 | ((pdata && pdata->use_onchip_ref) ? |
| 139 | 0 : AD7887_REF_DIS); |
| 140 | |
| 141 | st->xfer[0].rx_buf = &st->data[0]; |
| 142 | st->xfer[0].tx_buf = &st->tx_cmd_buf[0]; |
| 143 | st->xfer[0].len = 2; |
| 144 | |
| 145 | spi_message_init(&st->msg[AD7887_CH0]); |
| 146 | spi_message_add_tail(&st->xfer[0], &st->msg[AD7887_CH0]); |
| 147 | |
| 148 | if (pdata && pdata->en_dual) { |
| 149 | st->tx_cmd_buf[0] |= AD7887_DUAL | AD7887_REF_DIS; |
| 150 | |
| 151 | st->tx_cmd_buf[2] = AD7887_CH_AIN1 | AD7887_DUAL | |
| 152 | AD7887_REF_DIS | AD7887_PM_MODE4; |
| 153 | st->tx_cmd_buf[4] = AD7887_CH_AIN0 | AD7887_DUAL | |
| 154 | AD7887_REF_DIS | AD7887_PM_MODE4; |
| 155 | st->tx_cmd_buf[6] = AD7887_CH_AIN1 | AD7887_DUAL | |
| 156 | AD7887_REF_DIS | AD7887_PM_MODE4; |
| 157 | |
| 158 | st->xfer[1].rx_buf = &st->data[0]; |
| 159 | st->xfer[1].tx_buf = &st->tx_cmd_buf[2]; |
| 160 | st->xfer[1].len = 2; |
| 161 | |
| 162 | st->xfer[2].rx_buf = &st->data[2]; |
| 163 | st->xfer[2].tx_buf = &st->tx_cmd_buf[4]; |
| 164 | st->xfer[2].len = 2; |
| 165 | |
| 166 | spi_message_init(&st->msg[AD7887_CH0_CH1]); |
| 167 | spi_message_add_tail(&st->xfer[1], &st->msg[AD7887_CH0_CH1]); |
| 168 | spi_message_add_tail(&st->xfer[2], &st->msg[AD7887_CH0_CH1]); |
| 169 | |
| 170 | st->xfer[3].rx_buf = &st->data[0]; |
| 171 | st->xfer[3].tx_buf = &st->tx_cmd_buf[6]; |
| 172 | st->xfer[3].len = 2; |
| 173 | |
| 174 | spi_message_init(&st->msg[AD7887_CH1]); |
| 175 | spi_message_add_tail(&st->xfer[3], &st->msg[AD7887_CH1]); |
| 176 | |
Michael Hennerich | 2b4756a | 2010-11-22 14:35:32 +0100 | [diff] [blame] | 177 | if (pdata && pdata->vref_mv) |
| 178 | st->int_vref_mv = pdata->vref_mv; |
| 179 | else if (voltage_uv) |
| 180 | st->int_vref_mv = voltage_uv / 1000; |
| 181 | else |
| 182 | dev_warn(&spi->dev, "reference voltage unspecified\n"); |
| 183 | |
Michael Hennerich | f39e086 | 2011-05-18 14:41:51 +0100 | [diff] [blame] | 184 | indio_dev->channels = st->chip_info->channel; |
| 185 | indio_dev->num_channels = 3; |
Michael Hennerich | 2b4756a | 2010-11-22 14:35:32 +0100 | [diff] [blame] | 186 | } else { |
| 187 | if (pdata && pdata->vref_mv) |
| 188 | st->int_vref_mv = pdata->vref_mv; |
| 189 | else if (pdata && pdata->use_onchip_ref) |
| 190 | st->int_vref_mv = st->chip_info->int_vref_mv; |
| 191 | else |
| 192 | dev_warn(&spi->dev, "reference voltage unspecified\n"); |
Michael Hennerich | 2b4756a | 2010-11-22 14:35:32 +0100 | [diff] [blame] | 193 | |
Michael Hennerich | f39e086 | 2011-05-18 14:41:51 +0100 | [diff] [blame] | 194 | indio_dev->channels = &st->chip_info->channel[1]; |
| 195 | indio_dev->num_channels = 2; |
Michael Hennerich | 596d060 | 2011-05-18 14:41:50 +0100 | [diff] [blame] | 196 | } |
Michael Hennerich | 2b4756a | 2010-11-22 14:35:32 +0100 | [diff] [blame] | 197 | |
Michael Hennerich | f39e086 | 2011-05-18 14:41:51 +0100 | [diff] [blame] | 198 | ret = ad7887_register_ring_funcs_and_init(indio_dev); |
Michael Hennerich | 2b4756a | 2010-11-22 14:35:32 +0100 | [diff] [blame] | 199 | if (ret) |
Michael Hennerich | f39e086 | 2011-05-18 14:41:51 +0100 | [diff] [blame] | 200 | goto error_disable_reg; |
Michael Hennerich | 2b4756a | 2010-11-22 14:35:32 +0100 | [diff] [blame] | 201 | |
Jonathan Cameron | 14555b1 | 2011-09-21 11:15:57 +0100 | [diff] [blame] | 202 | ret = iio_buffer_register(indio_dev, |
| 203 | indio_dev->channels, |
| 204 | indio_dev->num_channels); |
Michael Hennerich | 2b4756a | 2010-11-22 14:35:32 +0100 | [diff] [blame] | 205 | if (ret) |
| 206 | goto error_cleanup_ring; |
Michael Hennerich | 2b4756a | 2010-11-22 14:35:32 +0100 | [diff] [blame] | 207 | |
Jonathan Cameron | 26d25ae | 2011-09-02 17:14:40 +0100 | [diff] [blame] | 208 | ret = iio_device_register(indio_dev); |
| 209 | if (ret) |
| 210 | goto error_unregister_ring; |
| 211 | |
| 212 | return 0; |
| 213 | error_unregister_ring: |
Jonathan Cameron | 14555b1 | 2011-09-21 11:15:57 +0100 | [diff] [blame] | 214 | iio_buffer_unregister(indio_dev); |
Michael Hennerich | 2b4756a | 2010-11-22 14:35:32 +0100 | [diff] [blame] | 215 | error_cleanup_ring: |
Michael Hennerich | f39e086 | 2011-05-18 14:41:51 +0100 | [diff] [blame] | 216 | ad7887_ring_cleanup(indio_dev); |
Michael Hennerich | 2b4756a | 2010-11-22 14:35:32 +0100 | [diff] [blame] | 217 | error_disable_reg: |
| 218 | if (!IS_ERR(st->reg)) |
| 219 | regulator_disable(st->reg); |
| 220 | error_put_reg: |
| 221 | if (!IS_ERR(st->reg)) |
| 222 | regulator_put(st->reg); |
Jonathan Cameron | 26d25ae | 2011-09-02 17:14:40 +0100 | [diff] [blame] | 223 | iio_free_device(indio_dev); |
Michael Hennerich | f39e086 | 2011-05-18 14:41:51 +0100 | [diff] [blame] | 224 | |
Michael Hennerich | 2b4756a | 2010-11-22 14:35:32 +0100 | [diff] [blame] | 225 | return ret; |
| 226 | } |
| 227 | |
| 228 | static int ad7887_remove(struct spi_device *spi) |
| 229 | { |
Michael Hennerich | f39e086 | 2011-05-18 14:41:51 +0100 | [diff] [blame] | 230 | struct iio_dev *indio_dev = spi_get_drvdata(spi); |
| 231 | struct ad7887_state *st = iio_priv(indio_dev); |
| 232 | |
Jonathan Cameron | d2fffd6 | 2011-10-14 14:46:58 +0100 | [diff] [blame] | 233 | iio_device_unregister(indio_dev); |
Jonathan Cameron | 14555b1 | 2011-09-21 11:15:57 +0100 | [diff] [blame] | 234 | iio_buffer_unregister(indio_dev); |
Michael Hennerich | 2b4756a | 2010-11-22 14:35:32 +0100 | [diff] [blame] | 235 | ad7887_ring_cleanup(indio_dev); |
Michael Hennerich | 2b4756a | 2010-11-22 14:35:32 +0100 | [diff] [blame] | 236 | if (!IS_ERR(st->reg)) { |
| 237 | regulator_disable(st->reg); |
| 238 | regulator_put(st->reg); |
| 239 | } |
Jonathan Cameron | d2fffd6 | 2011-10-14 14:46:58 +0100 | [diff] [blame] | 240 | iio_free_device(indio_dev); |
Michael Hennerich | f39e086 | 2011-05-18 14:41:51 +0100 | [diff] [blame] | 241 | |
Michael Hennerich | 2b4756a | 2010-11-22 14:35:32 +0100 | [diff] [blame] | 242 | return 0; |
| 243 | } |
| 244 | |
| 245 | static const struct spi_device_id ad7887_id[] = { |
| 246 | {"ad7887", ID_AD7887}, |
| 247 | {} |
| 248 | }; |
| 249 | |
| 250 | static struct spi_driver ad7887_driver = { |
| 251 | .driver = { |
| 252 | .name = "ad7887", |
| 253 | .bus = &spi_bus_type, |
| 254 | .owner = THIS_MODULE, |
| 255 | }, |
| 256 | .probe = ad7887_probe, |
| 257 | .remove = __devexit_p(ad7887_remove), |
| 258 | .id_table = ad7887_id, |
| 259 | }; |
| 260 | |
| 261 | static int __init ad7887_init(void) |
| 262 | { |
| 263 | return spi_register_driver(&ad7887_driver); |
| 264 | } |
| 265 | module_init(ad7887_init); |
| 266 | |
| 267 | static void __exit ad7887_exit(void) |
| 268 | { |
| 269 | spi_unregister_driver(&ad7887_driver); |
| 270 | } |
| 271 | module_exit(ad7887_exit); |
| 272 | |
| 273 | MODULE_AUTHOR("Michael Hennerich <hennerich@blackfin.uclinux.org>"); |
| 274 | MODULE_DESCRIPTION("Analog Devices AD7887 ADC"); |
| 275 | MODULE_LICENSE("GPL v2"); |
| 276 | MODULE_ALIAS("spi:ad7887"); |