Lars-Peter Clausen | 68b14d7 | 2011-12-05 17:05:41 +0100 | [diff] [blame] | 1 | /* |
| 2 | * Analog devices AD5764, AD5764R, AD5744, AD5744R quad-channel |
| 3 | * Digital to Analog Converters driver |
| 4 | * |
| 5 | * Copyright 2011 Analog Devices Inc. |
| 6 | * |
| 7 | * Licensed under the GPL-2. |
| 8 | */ |
| 9 | |
| 10 | #include <linux/device.h> |
| 11 | #include <linux/err.h> |
| 12 | #include <linux/module.h> |
| 13 | #include <linux/kernel.h> |
| 14 | #include <linux/spi/spi.h> |
| 15 | #include <linux/slab.h> |
| 16 | #include <linux/sysfs.h> |
| 17 | #include <linux/regulator/consumer.h> |
| 18 | |
Jonathan Cameron | 06458e2 | 2012-04-25 15:54:58 +0100 | [diff] [blame] | 19 | #include <linux/iio/iio.h> |
| 20 | #include <linux/iio/sysfs.h> |
Lars-Peter Clausen | 68b14d7 | 2011-12-05 17:05:41 +0100 | [diff] [blame] | 21 | |
| 22 | #define AD5764_REG_SF_NOP 0x0 |
| 23 | #define AD5764_REG_SF_CONFIG 0x1 |
| 24 | #define AD5764_REG_SF_CLEAR 0x4 |
| 25 | #define AD5764_REG_SF_LOAD 0x5 |
| 26 | #define AD5764_REG_DATA(x) ((2 << 3) | (x)) |
| 27 | #define AD5764_REG_COARSE_GAIN(x) ((3 << 3) | (x)) |
| 28 | #define AD5764_REG_FINE_GAIN(x) ((4 << 3) | (x)) |
| 29 | #define AD5764_REG_OFFSET(x) ((5 << 3) | (x)) |
| 30 | |
| 31 | #define AD5764_NUM_CHANNELS 4 |
| 32 | |
| 33 | /** |
| 34 | * struct ad5764_chip_info - chip specific information |
| 35 | * @int_vref: Value of the internal reference voltage in uV - 0 if external |
| 36 | * reference voltage is used |
| 37 | * @channel channel specification |
| 38 | */ |
| 39 | |
| 40 | struct ad5764_chip_info { |
| 41 | unsigned long int_vref; |
| 42 | const struct iio_chan_spec *channels; |
| 43 | }; |
| 44 | |
| 45 | /** |
| 46 | * struct ad5764_state - driver instance specific data |
| 47 | * @spi: spi_device |
| 48 | * @chip_info: chip info |
| 49 | * @vref_reg: vref supply regulators |
| 50 | * @data: spi transfer buffers |
| 51 | */ |
| 52 | |
| 53 | struct ad5764_state { |
| 54 | struct spi_device *spi; |
| 55 | const struct ad5764_chip_info *chip_info; |
| 56 | struct regulator_bulk_data vref_reg[2]; |
| 57 | |
| 58 | /* |
| 59 | * DMA (thus cache coherency maintenance) requires the |
| 60 | * transfer buffers to live in their own cache lines. |
| 61 | */ |
| 62 | union { |
| 63 | __be32 d32; |
| 64 | u8 d8[4]; |
| 65 | } data[2] ____cacheline_aligned; |
| 66 | }; |
| 67 | |
| 68 | enum ad5764_type { |
| 69 | ID_AD5744, |
| 70 | ID_AD5744R, |
| 71 | ID_AD5764, |
| 72 | ID_AD5764R, |
| 73 | }; |
| 74 | |
| 75 | #define AD5764_CHANNEL(_chan, _bits) { \ |
| 76 | .type = IIO_VOLTAGE, \ |
| 77 | .indexed = 1, \ |
| 78 | .output = 1, \ |
| 79 | .channel = (_chan), \ |
| 80 | .address = (_chan), \ |
Jonathan Cameron | f4d9df1 | 2013-02-27 19:28:00 +0000 | [diff] [blame] | 81 | .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) | \ |
| 82 | BIT(IIO_CHAN_INFO_SCALE) | \ |
| 83 | BIT(IIO_CHAN_INFO_CALIBSCALE) | \ |
| 84 | BIT(IIO_CHAN_INFO_CALIBBIAS), \ |
| 85 | .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_OFFSET), \ |
Lars-Peter Clausen | 68b14d7 | 2011-12-05 17:05:41 +0100 | [diff] [blame] | 86 | .scan_type = IIO_ST('u', (_bits), 16, 16 - (_bits)) \ |
| 87 | } |
| 88 | |
| 89 | #define DECLARE_AD5764_CHANNELS(_name, _bits) \ |
| 90 | const struct iio_chan_spec _name##_channels[] = { \ |
| 91 | AD5764_CHANNEL(0, (_bits)), \ |
| 92 | AD5764_CHANNEL(1, (_bits)), \ |
| 93 | AD5764_CHANNEL(2, (_bits)), \ |
| 94 | AD5764_CHANNEL(3, (_bits)), \ |
| 95 | }; |
| 96 | |
| 97 | static DECLARE_AD5764_CHANNELS(ad5764, 16); |
| 98 | static DECLARE_AD5764_CHANNELS(ad5744, 14); |
| 99 | |
| 100 | static const struct ad5764_chip_info ad5764_chip_infos[] = { |
| 101 | [ID_AD5744] = { |
| 102 | .int_vref = 0, |
| 103 | .channels = ad5744_channels, |
| 104 | }, |
| 105 | [ID_AD5744R] = { |
| 106 | .int_vref = 5000000, |
| 107 | .channels = ad5744_channels, |
| 108 | }, |
| 109 | [ID_AD5764] = { |
| 110 | .int_vref = 0, |
| 111 | .channels = ad5764_channels, |
| 112 | }, |
| 113 | [ID_AD5764R] = { |
| 114 | .int_vref = 5000000, |
| 115 | .channels = ad5764_channels, |
| 116 | }, |
| 117 | }; |
| 118 | |
| 119 | static int ad5764_write(struct iio_dev *indio_dev, unsigned int reg, |
| 120 | unsigned int val) |
| 121 | { |
| 122 | struct ad5764_state *st = iio_priv(indio_dev); |
| 123 | int ret; |
| 124 | |
| 125 | mutex_lock(&indio_dev->mlock); |
| 126 | st->data[0].d32 = cpu_to_be32((reg << 16) | val); |
| 127 | |
| 128 | ret = spi_write(st->spi, &st->data[0].d8[1], 3); |
| 129 | mutex_unlock(&indio_dev->mlock); |
| 130 | |
| 131 | return ret; |
| 132 | } |
| 133 | |
| 134 | static int ad5764_read(struct iio_dev *indio_dev, unsigned int reg, |
| 135 | unsigned int *val) |
| 136 | { |
| 137 | struct ad5764_state *st = iio_priv(indio_dev); |
Lars-Peter Clausen | 68b14d7 | 2011-12-05 17:05:41 +0100 | [diff] [blame] | 138 | int ret; |
| 139 | struct spi_transfer t[] = { |
| 140 | { |
| 141 | .tx_buf = &st->data[0].d8[1], |
| 142 | .len = 3, |
| 143 | .cs_change = 1, |
| 144 | }, { |
| 145 | .rx_buf = &st->data[1].d8[1], |
| 146 | .len = 3, |
| 147 | }, |
| 148 | }; |
| 149 | |
Lars-Peter Clausen | 68b14d7 | 2011-12-05 17:05:41 +0100 | [diff] [blame] | 150 | mutex_lock(&indio_dev->mlock); |
| 151 | |
| 152 | st->data[0].d32 = cpu_to_be32((1 << 23) | (reg << 16)); |
| 153 | |
Lars-Peter Clausen | 14543a0 | 2013-01-09 17:31:00 +0000 | [diff] [blame] | 154 | ret = spi_sync_transfer(st->spi, t, ARRAY_SIZE(t)); |
Lars-Peter Clausen | 68b14d7 | 2011-12-05 17:05:41 +0100 | [diff] [blame] | 155 | if (ret >= 0) |
| 156 | *val = be32_to_cpu(st->data[1].d32) & 0xffff; |
| 157 | |
| 158 | mutex_unlock(&indio_dev->mlock); |
| 159 | |
| 160 | return ret; |
| 161 | } |
| 162 | |
| 163 | static int ad5764_chan_info_to_reg(struct iio_chan_spec const *chan, long info) |
| 164 | { |
| 165 | switch (info) { |
| 166 | case 0: |
| 167 | return AD5764_REG_DATA(chan->address); |
| 168 | case IIO_CHAN_INFO_CALIBBIAS: |
| 169 | return AD5764_REG_OFFSET(chan->address); |
| 170 | case IIO_CHAN_INFO_CALIBSCALE: |
| 171 | return AD5764_REG_FINE_GAIN(chan->address); |
| 172 | default: |
| 173 | break; |
| 174 | } |
| 175 | |
| 176 | return 0; |
| 177 | } |
| 178 | |
| 179 | static int ad5764_write_raw(struct iio_dev *indio_dev, |
| 180 | struct iio_chan_spec const *chan, int val, int val2, long info) |
| 181 | { |
| 182 | const int max_val = (1 << chan->scan_type.realbits); |
| 183 | unsigned int reg; |
| 184 | |
| 185 | switch (info) { |
Jonathan Cameron | 09f4eb4 | 2012-04-15 17:41:19 +0100 | [diff] [blame] | 186 | case IIO_CHAN_INFO_RAW: |
Lars-Peter Clausen | 68b14d7 | 2011-12-05 17:05:41 +0100 | [diff] [blame] | 187 | if (val >= max_val || val < 0) |
| 188 | return -EINVAL; |
| 189 | val <<= chan->scan_type.shift; |
| 190 | break; |
| 191 | case IIO_CHAN_INFO_CALIBBIAS: |
| 192 | if (val >= 128 || val < -128) |
| 193 | return -EINVAL; |
| 194 | break; |
| 195 | case IIO_CHAN_INFO_CALIBSCALE: |
| 196 | if (val >= 32 || val < -32) |
| 197 | return -EINVAL; |
| 198 | break; |
| 199 | default: |
| 200 | return -EINVAL; |
| 201 | } |
| 202 | |
| 203 | reg = ad5764_chan_info_to_reg(chan, info); |
| 204 | return ad5764_write(indio_dev, reg, (u16)val); |
| 205 | } |
| 206 | |
| 207 | static int ad5764_get_channel_vref(struct ad5764_state *st, |
| 208 | unsigned int channel) |
| 209 | { |
| 210 | if (st->chip_info->int_vref) |
| 211 | return st->chip_info->int_vref; |
| 212 | else |
| 213 | return regulator_get_voltage(st->vref_reg[channel / 2].consumer); |
| 214 | } |
| 215 | |
| 216 | static int ad5764_read_raw(struct iio_dev *indio_dev, |
| 217 | struct iio_chan_spec const *chan, int *val, int *val2, long info) |
| 218 | { |
| 219 | struct ad5764_state *st = iio_priv(indio_dev); |
| 220 | unsigned long scale_uv; |
| 221 | unsigned int reg; |
| 222 | int vref; |
| 223 | int ret; |
| 224 | |
| 225 | switch (info) { |
Jonathan Cameron | 09f4eb4 | 2012-04-15 17:41:19 +0100 | [diff] [blame] | 226 | case IIO_CHAN_INFO_RAW: |
Lars-Peter Clausen | 68b14d7 | 2011-12-05 17:05:41 +0100 | [diff] [blame] | 227 | reg = AD5764_REG_DATA(chan->address); |
| 228 | ret = ad5764_read(indio_dev, reg, val); |
| 229 | if (ret < 0) |
| 230 | return ret; |
| 231 | *val >>= chan->scan_type.shift; |
| 232 | return IIO_VAL_INT; |
| 233 | case IIO_CHAN_INFO_CALIBBIAS: |
| 234 | reg = AD5764_REG_OFFSET(chan->address); |
| 235 | ret = ad5764_read(indio_dev, reg, val); |
| 236 | if (ret < 0) |
| 237 | return ret; |
| 238 | *val = sign_extend32(*val, 7); |
| 239 | return IIO_VAL_INT; |
| 240 | case IIO_CHAN_INFO_CALIBSCALE: |
| 241 | reg = AD5764_REG_FINE_GAIN(chan->address); |
| 242 | ret = ad5764_read(indio_dev, reg, val); |
| 243 | if (ret < 0) |
| 244 | return ret; |
| 245 | *val = sign_extend32(*val, 5); |
| 246 | return IIO_VAL_INT; |
| 247 | case IIO_CHAN_INFO_SCALE: |
| 248 | /* vout = 4 * vref + ((dac_code / 65535) - 0.5) */ |
| 249 | vref = ad5764_get_channel_vref(st, chan->channel); |
| 250 | if (vref < 0) |
| 251 | return vref; |
| 252 | |
| 253 | scale_uv = (vref * 4 * 100) >> chan->scan_type.realbits; |
| 254 | *val = scale_uv / 100000; |
| 255 | *val2 = (scale_uv % 100000) * 10; |
| 256 | return IIO_VAL_INT_PLUS_MICRO; |
| 257 | case IIO_CHAN_INFO_OFFSET: |
| 258 | *val = -(1 << chan->scan_type.realbits) / 2; |
| 259 | return IIO_VAL_INT; |
| 260 | } |
| 261 | |
| 262 | return -EINVAL; |
| 263 | } |
| 264 | |
| 265 | static const struct iio_info ad5764_info = { |
| 266 | .read_raw = ad5764_read_raw, |
| 267 | .write_raw = ad5764_write_raw, |
| 268 | .driver_module = THIS_MODULE, |
| 269 | }; |
| 270 | |
Greg Kroah-Hartman | fc52692 | 2012-12-21 13:21:43 -0800 | [diff] [blame] | 271 | static int ad5764_probe(struct spi_device *spi) |
Lars-Peter Clausen | 68b14d7 | 2011-12-05 17:05:41 +0100 | [diff] [blame] | 272 | { |
| 273 | enum ad5764_type type = spi_get_device_id(spi)->driver_data; |
| 274 | struct iio_dev *indio_dev; |
| 275 | struct ad5764_state *st; |
| 276 | int ret; |
| 277 | |
Lars-Peter Clausen | 7cbb753 | 2012-04-26 13:35:01 +0200 | [diff] [blame] | 278 | indio_dev = iio_device_alloc(sizeof(*st)); |
Lars-Peter Clausen | 68b14d7 | 2011-12-05 17:05:41 +0100 | [diff] [blame] | 279 | if (indio_dev == NULL) { |
| 280 | dev_err(&spi->dev, "Failed to allocate iio device\n"); |
| 281 | return -ENOMEM; |
| 282 | } |
| 283 | |
| 284 | st = iio_priv(indio_dev); |
| 285 | spi_set_drvdata(spi, indio_dev); |
| 286 | |
| 287 | st->spi = spi; |
| 288 | st->chip_info = &ad5764_chip_infos[type]; |
| 289 | |
| 290 | indio_dev->dev.parent = &spi->dev; |
| 291 | indio_dev->name = spi_get_device_id(spi)->name; |
| 292 | indio_dev->info = &ad5764_info; |
| 293 | indio_dev->modes = INDIO_DIRECT_MODE; |
| 294 | indio_dev->num_channels = AD5764_NUM_CHANNELS; |
| 295 | indio_dev->channels = st->chip_info->channels; |
| 296 | |
| 297 | if (st->chip_info->int_vref == 0) { |
| 298 | st->vref_reg[0].supply = "vrefAB"; |
| 299 | st->vref_reg[1].supply = "vrefCD"; |
| 300 | |
| 301 | ret = regulator_bulk_get(&st->spi->dev, |
| 302 | ARRAY_SIZE(st->vref_reg), st->vref_reg); |
| 303 | if (ret) { |
| 304 | dev_err(&spi->dev, "Failed to request vref regulators: %d\n", |
| 305 | ret); |
| 306 | goto error_free; |
| 307 | } |
| 308 | |
| 309 | ret = regulator_bulk_enable(ARRAY_SIZE(st->vref_reg), |
| 310 | st->vref_reg); |
| 311 | if (ret) { |
| 312 | dev_err(&spi->dev, "Failed to enable vref regulators: %d\n", |
| 313 | ret); |
| 314 | goto error_free_reg; |
| 315 | } |
| 316 | } |
| 317 | |
| 318 | ret = iio_device_register(indio_dev); |
| 319 | if (ret) { |
| 320 | dev_err(&spi->dev, "Failed to register iio device: %d\n", ret); |
| 321 | goto error_disable_reg; |
| 322 | } |
| 323 | |
| 324 | return 0; |
| 325 | |
| 326 | error_disable_reg: |
| 327 | if (st->chip_info->int_vref == 0) |
| 328 | regulator_bulk_disable(ARRAY_SIZE(st->vref_reg), st->vref_reg); |
| 329 | error_free_reg: |
| 330 | if (st->chip_info->int_vref == 0) |
| 331 | regulator_bulk_free(ARRAY_SIZE(st->vref_reg), st->vref_reg); |
| 332 | error_free: |
Lars-Peter Clausen | 7cbb753 | 2012-04-26 13:35:01 +0200 | [diff] [blame] | 333 | iio_device_free(indio_dev); |
Lars-Peter Clausen | 68b14d7 | 2011-12-05 17:05:41 +0100 | [diff] [blame] | 334 | |
| 335 | return ret; |
| 336 | } |
| 337 | |
Greg Kroah-Hartman | fc52692 | 2012-12-21 13:21:43 -0800 | [diff] [blame] | 338 | static int ad5764_remove(struct spi_device *spi) |
Lars-Peter Clausen | 68b14d7 | 2011-12-05 17:05:41 +0100 | [diff] [blame] | 339 | { |
| 340 | struct iio_dev *indio_dev = spi_get_drvdata(spi); |
| 341 | struct ad5764_state *st = iio_priv(indio_dev); |
| 342 | |
| 343 | iio_device_unregister(indio_dev); |
| 344 | |
| 345 | if (st->chip_info->int_vref == 0) { |
| 346 | regulator_bulk_disable(ARRAY_SIZE(st->vref_reg), st->vref_reg); |
| 347 | regulator_bulk_free(ARRAY_SIZE(st->vref_reg), st->vref_reg); |
| 348 | } |
| 349 | |
Lars-Peter Clausen | 7cbb753 | 2012-04-26 13:35:01 +0200 | [diff] [blame] | 350 | iio_device_free(indio_dev); |
Lars-Peter Clausen | 68b14d7 | 2011-12-05 17:05:41 +0100 | [diff] [blame] | 351 | |
| 352 | return 0; |
| 353 | } |
| 354 | |
| 355 | static const struct spi_device_id ad5764_ids[] = { |
| 356 | { "ad5744", ID_AD5744 }, |
| 357 | { "ad5744r", ID_AD5744R }, |
| 358 | { "ad5764", ID_AD5764 }, |
| 359 | { "ad5764r", ID_AD5764R }, |
| 360 | { } |
| 361 | }; |
| 362 | MODULE_DEVICE_TABLE(spi, ad5764_ids); |
| 363 | |
| 364 | static struct spi_driver ad5764_driver = { |
| 365 | .driver = { |
| 366 | .name = "ad5764", |
| 367 | .owner = THIS_MODULE, |
| 368 | }, |
| 369 | .probe = ad5764_probe, |
Greg Kroah-Hartman | fc52692 | 2012-12-21 13:21:43 -0800 | [diff] [blame] | 370 | .remove = ad5764_remove, |
Lars-Peter Clausen | 68b14d7 | 2011-12-05 17:05:41 +0100 | [diff] [blame] | 371 | .id_table = ad5764_ids, |
| 372 | }; |
Lars-Peter Clausen | 519ff1d | 2012-02-20 19:42:38 +0100 | [diff] [blame] | 373 | module_spi_driver(ad5764_driver); |
Lars-Peter Clausen | 68b14d7 | 2011-12-05 17:05:41 +0100 | [diff] [blame] | 374 | |
| 375 | MODULE_AUTHOR("Lars-Peter Clausen <lars@metafoo.de>"); |
| 376 | MODULE_DESCRIPTION("Analog Devices AD5744/AD5744R/AD5764/AD5764R DAC"); |
| 377 | MODULE_LICENSE("GPL v2"); |