Michael Hennerich | c2f37c8 | 2011-06-10 15:40:49 +0200 | [diff] [blame] | 1 | /* |
| 2 | * AD5686R, AD5685R, AD5684R Digital to analog converters driver |
| 3 | * |
| 4 | * Copyright 2011 Analog Devices Inc. |
| 5 | * |
| 6 | * Licensed under the GPL-2. |
| 7 | */ |
| 8 | |
| 9 | #include <linux/interrupt.h> |
| 10 | #include <linux/gpio.h> |
| 11 | #include <linux/fs.h> |
| 12 | #include <linux/device.h> |
Paul Gortmaker | 99c9785 | 2011-07-03 15:49:50 -0400 | [diff] [blame] | 13 | #include <linux/module.h> |
Michael Hennerich | c2f37c8 | 2011-06-10 15:40:49 +0200 | [diff] [blame] | 14 | #include <linux/kernel.h> |
| 15 | #include <linux/spi/spi.h> |
| 16 | #include <linux/slab.h> |
| 17 | #include <linux/sysfs.h> |
| 18 | #include <linux/regulator/consumer.h> |
| 19 | |
| 20 | #include "../iio.h" |
| 21 | #include "../sysfs.h" |
| 22 | #include "dac.h" |
| 23 | |
| 24 | #define AD5686_DAC_CHANNELS 4 |
| 25 | |
| 26 | #define AD5686_ADDR(x) ((x) << 16) |
| 27 | #define AD5686_CMD(x) ((x) << 20) |
| 28 | |
| 29 | #define AD5686_ADDR_DAC0 0x1 |
| 30 | #define AD5686_ADDR_DAC1 0x2 |
| 31 | #define AD5686_ADDR_DAC2 0x4 |
| 32 | #define AD5686_ADDR_DAC3 0x8 |
| 33 | #define AD5686_ADDR_ALL_DAC 0xF |
| 34 | |
| 35 | #define AD5686_CMD_NOOP 0x0 |
| 36 | #define AD5686_CMD_WRITE_INPUT_N 0x1 |
| 37 | #define AD5686_CMD_UPDATE_DAC_N 0x2 |
| 38 | #define AD5686_CMD_WRITE_INPUT_N_UPDATE_N 0x3 |
| 39 | #define AD5686_CMD_POWERDOWN_DAC 0x4 |
| 40 | #define AD5686_CMD_LDAC_MASK 0x5 |
| 41 | #define AD5686_CMD_RESET 0x6 |
| 42 | #define AD5686_CMD_INTERNAL_REFER_SETUP 0x7 |
| 43 | #define AD5686_CMD_DAISY_CHAIN_ENABLE 0x8 |
| 44 | #define AD5686_CMD_READBACK_ENABLE 0x9 |
| 45 | |
| 46 | #define AD5686_LDAC_PWRDN_NONE 0x0 |
| 47 | #define AD5686_LDAC_PWRDN_1K 0x1 |
| 48 | #define AD5686_LDAC_PWRDN_100K 0x2 |
| 49 | #define AD5686_LDAC_PWRDN_3STATE 0x3 |
| 50 | |
| 51 | /** |
| 52 | * struct ad5686_chip_info - chip specific information |
| 53 | * @int_vref_mv: AD5620/40/60: the internal reference voltage |
| 54 | * @channel: channel specification |
| 55 | */ |
| 56 | |
| 57 | struct ad5686_chip_info { |
| 58 | u16 int_vref_mv; |
| 59 | struct iio_chan_spec channel[AD5686_DAC_CHANNELS]; |
| 60 | }; |
| 61 | |
| 62 | /** |
| 63 | * struct ad5446_state - driver instance specific data |
| 64 | * @spi: spi_device |
| 65 | * @chip_info: chip model specific constants, available modes etc |
| 66 | * @reg: supply regulator |
| 67 | * @vref_mv: actual reference voltage used |
| 68 | * @pwr_down_mask: power down mask |
| 69 | * @pwr_down_mode: current power down mode |
| 70 | * @data: spi transfer buffers |
| 71 | */ |
| 72 | |
| 73 | struct ad5686_state { |
| 74 | struct spi_device *spi; |
| 75 | const struct ad5686_chip_info *chip_info; |
| 76 | struct regulator *reg; |
| 77 | unsigned short vref_mv; |
| 78 | unsigned pwr_down_mask; |
| 79 | unsigned pwr_down_mode; |
| 80 | /* |
| 81 | * DMA (thus cache coherency maintenance) requires the |
| 82 | * transfer buffers to live in their own cache lines. |
| 83 | */ |
| 84 | |
| 85 | union { |
| 86 | u32 d32; |
| 87 | u8 d8[4]; |
| 88 | } data[3] ____cacheline_aligned; |
| 89 | }; |
| 90 | |
| 91 | /** |
| 92 | * ad5686_supported_device_ids: |
| 93 | */ |
| 94 | |
| 95 | enum ad5686_supported_device_ids { |
| 96 | ID_AD5684, |
| 97 | ID_AD5685, |
| 98 | ID_AD5686, |
| 99 | }; |
Jonathan Cameron | c6fc806 | 2011-09-02 17:14:34 +0100 | [diff] [blame] | 100 | #define AD5868_CHANNEL(chan, bits, shift) { \ |
| 101 | .type = IIO_VOLTAGE, \ |
| 102 | .indexed = 1, \ |
| 103 | .output = 1, \ |
| 104 | .channel = chan, \ |
| 105 | .info_mask = (1 << IIO_CHAN_INFO_SCALE_SHARED), \ |
| 106 | .address = AD5686_ADDR_DAC0, \ |
| 107 | .scan_type = IIO_ST('u', bits, 16, shift) \ |
| 108 | } |
Michael Hennerich | c2f37c8 | 2011-06-10 15:40:49 +0200 | [diff] [blame] | 109 | static const struct ad5686_chip_info ad5686_chip_info_tbl[] = { |
| 110 | [ID_AD5684] = { |
Jonathan Cameron | c6fc806 | 2011-09-02 17:14:34 +0100 | [diff] [blame] | 111 | .channel[0] = AD5868_CHANNEL(0, 12, 4), |
| 112 | .channel[1] = AD5868_CHANNEL(1, 12, 4), |
| 113 | .channel[2] = AD5868_CHANNEL(2, 12, 4), |
| 114 | .channel[3] = AD5868_CHANNEL(3, 12, 4), |
Michael Hennerich | c2f37c8 | 2011-06-10 15:40:49 +0200 | [diff] [blame] | 115 | .int_vref_mv = 2500, |
| 116 | }, |
| 117 | [ID_AD5685] = { |
Jonathan Cameron | c6fc806 | 2011-09-02 17:14:34 +0100 | [diff] [blame] | 118 | .channel[0] = AD5868_CHANNEL(0, 14, 2), |
| 119 | .channel[1] = AD5868_CHANNEL(1, 14, 2), |
| 120 | .channel[2] = AD5868_CHANNEL(2, 14, 2), |
| 121 | .channel[3] = AD5868_CHANNEL(3, 14, 2), |
Michael Hennerich | c2f37c8 | 2011-06-10 15:40:49 +0200 | [diff] [blame] | 122 | .int_vref_mv = 2500, |
| 123 | }, |
| 124 | [ID_AD5686] = { |
Jonathan Cameron | c6fc806 | 2011-09-02 17:14:34 +0100 | [diff] [blame] | 125 | .channel[0] = AD5868_CHANNEL(0, 16, 0), |
| 126 | .channel[1] = AD5868_CHANNEL(1, 16, 0), |
| 127 | .channel[2] = AD5868_CHANNEL(2, 16, 0), |
| 128 | .channel[3] = AD5868_CHANNEL(3, 16, 0), |
Michael Hennerich | c2f37c8 | 2011-06-10 15:40:49 +0200 | [diff] [blame] | 129 | .int_vref_mv = 2500, |
| 130 | }, |
| 131 | }; |
| 132 | |
| 133 | static int ad5686_spi_write(struct ad5686_state *st, |
| 134 | u8 cmd, u8 addr, u16 val, u8 shift) |
| 135 | { |
| 136 | val <<= shift; |
| 137 | |
| 138 | st->data[0].d32 = cpu_to_be32(AD5686_CMD(cmd) | |
| 139 | AD5686_ADDR(addr) | |
| 140 | val); |
| 141 | |
| 142 | return spi_write(st->spi, &st->data[0].d8[1], 3); |
| 143 | } |
| 144 | |
| 145 | static int ad5686_spi_read(struct ad5686_state *st, u8 addr) |
| 146 | { |
| 147 | struct spi_transfer t[] = { |
| 148 | { |
| 149 | .tx_buf = &st->data[0].d8[1], |
| 150 | .len = 3, |
| 151 | .cs_change = 1, |
| 152 | }, { |
| 153 | .tx_buf = &st->data[1].d8[1], |
| 154 | .rx_buf = &st->data[2].d8[1], |
| 155 | .len = 3, |
| 156 | }, |
| 157 | }; |
| 158 | struct spi_message m; |
| 159 | int ret; |
| 160 | |
| 161 | spi_message_init(&m); |
| 162 | spi_message_add_tail(&t[0], &m); |
| 163 | spi_message_add_tail(&t[1], &m); |
| 164 | |
| 165 | st->data[0].d32 = cpu_to_be32(AD5686_CMD(AD5686_CMD_READBACK_ENABLE) | |
| 166 | AD5686_ADDR(addr)); |
| 167 | st->data[1].d32 = cpu_to_be32(AD5686_CMD(AD5686_CMD_NOOP)); |
| 168 | |
| 169 | ret = spi_sync(st->spi, &m); |
| 170 | if (ret < 0) |
| 171 | return ret; |
| 172 | |
| 173 | return be32_to_cpu(st->data[2].d32); |
| 174 | } |
| 175 | |
| 176 | static ssize_t ad5686_read_powerdown_mode(struct device *dev, |
| 177 | struct device_attribute *attr, char *buf) |
| 178 | { |
| 179 | struct iio_dev *indio_dev = dev_get_drvdata(dev); |
| 180 | struct ad5686_state *st = iio_priv(indio_dev); |
| 181 | struct iio_dev_attr *this_attr = to_iio_dev_attr(attr); |
| 182 | |
| 183 | char mode[][15] = {"", "1kohm_to_gnd", "100kohm_to_gnd", "three_state"}; |
| 184 | |
| 185 | return sprintf(buf, "%s\n", mode[(st->pwr_down_mode >> |
| 186 | (this_attr->address * 2)) & 0x3]); |
| 187 | } |
| 188 | |
| 189 | static ssize_t ad5686_write_powerdown_mode(struct device *dev, |
| 190 | struct device_attribute *attr, |
| 191 | const char *buf, size_t len) |
| 192 | { |
| 193 | struct iio_dev *indio_dev = dev_get_drvdata(dev); |
| 194 | struct ad5686_state *st = iio_priv(indio_dev); |
| 195 | struct iio_dev_attr *this_attr = to_iio_dev_attr(attr); |
| 196 | unsigned mode; |
| 197 | |
| 198 | if (sysfs_streq(buf, "1kohm_to_gnd")) |
| 199 | mode = AD5686_LDAC_PWRDN_1K; |
| 200 | else if (sysfs_streq(buf, "100kohm_to_gnd")) |
| 201 | mode = AD5686_LDAC_PWRDN_100K; |
| 202 | else if (sysfs_streq(buf, "three_state")) |
| 203 | mode = AD5686_LDAC_PWRDN_3STATE; |
| 204 | else |
| 205 | return -EINVAL; |
| 206 | |
| 207 | st->pwr_down_mode &= ~(0x3 << (this_attr->address * 2)); |
| 208 | st->pwr_down_mode |= (mode << (this_attr->address * 2)); |
| 209 | |
| 210 | return len; |
| 211 | } |
| 212 | |
| 213 | static ssize_t ad5686_read_dac_powerdown(struct device *dev, |
| 214 | struct device_attribute *attr, |
| 215 | char *buf) |
| 216 | { |
| 217 | struct iio_dev *indio_dev = dev_get_drvdata(dev); |
| 218 | struct ad5686_state *st = iio_priv(indio_dev); |
| 219 | struct iio_dev_attr *this_attr = to_iio_dev_attr(attr); |
| 220 | |
| 221 | return sprintf(buf, "%d\n", !!(st->pwr_down_mask & |
| 222 | (0x3 << (this_attr->address * 2)))); |
| 223 | } |
| 224 | |
| 225 | static ssize_t ad5686_write_dac_powerdown(struct device *dev, |
| 226 | struct device_attribute *attr, |
| 227 | const char *buf, size_t len) |
| 228 | { |
| 229 | bool readin; |
| 230 | int ret; |
| 231 | struct iio_dev *indio_dev = dev_get_drvdata(dev); |
| 232 | struct ad5686_state *st = iio_priv(indio_dev); |
| 233 | struct iio_dev_attr *this_attr = to_iio_dev_attr(attr); |
| 234 | |
| 235 | ret = strtobool(buf, &readin); |
| 236 | if (ret) |
| 237 | return ret; |
| 238 | |
| 239 | if (readin == true) |
| 240 | st->pwr_down_mask |= (0x3 << (this_attr->address * 2)); |
| 241 | else |
| 242 | st->pwr_down_mask &= ~(0x3 << (this_attr->address * 2)); |
| 243 | |
| 244 | ret = ad5686_spi_write(st, AD5686_CMD_POWERDOWN_DAC, 0, |
| 245 | st->pwr_down_mask & st->pwr_down_mode, 0); |
| 246 | |
| 247 | return ret ? ret : len; |
| 248 | } |
| 249 | |
| 250 | static IIO_CONST_ATTR(out_powerdown_mode_available, |
| 251 | "1kohm_to_gnd 100kohm_to_gnd three_state"); |
| 252 | |
| 253 | #define IIO_DEV_ATTR_DAC_POWERDOWN_MODE(_num) \ |
| 254 | IIO_DEVICE_ATTR(out##_num##_powerdown_mode, S_IRUGO | S_IWUSR, \ |
| 255 | ad5686_read_powerdown_mode, \ |
| 256 | ad5686_write_powerdown_mode, _num) |
| 257 | |
| 258 | static IIO_DEV_ATTR_DAC_POWERDOWN_MODE(0); |
| 259 | static IIO_DEV_ATTR_DAC_POWERDOWN_MODE(1); |
| 260 | static IIO_DEV_ATTR_DAC_POWERDOWN_MODE(2); |
| 261 | static IIO_DEV_ATTR_DAC_POWERDOWN_MODE(3); |
| 262 | |
| 263 | #define IIO_DEV_ATTR_DAC_POWERDOWN(_num) \ |
| 264 | IIO_DEVICE_ATTR(out##_num##_powerdown, S_IRUGO | S_IWUSR, \ |
| 265 | ad5686_read_dac_powerdown, \ |
| 266 | ad5686_write_dac_powerdown, _num) |
| 267 | |
| 268 | static IIO_DEV_ATTR_DAC_POWERDOWN(0); |
| 269 | static IIO_DEV_ATTR_DAC_POWERDOWN(1); |
| 270 | static IIO_DEV_ATTR_DAC_POWERDOWN(2); |
| 271 | static IIO_DEV_ATTR_DAC_POWERDOWN(3); |
| 272 | |
| 273 | static struct attribute *ad5686_attributes[] = { |
| 274 | &iio_dev_attr_out0_powerdown.dev_attr.attr, |
| 275 | &iio_dev_attr_out1_powerdown.dev_attr.attr, |
| 276 | &iio_dev_attr_out2_powerdown.dev_attr.attr, |
| 277 | &iio_dev_attr_out3_powerdown.dev_attr.attr, |
| 278 | &iio_dev_attr_out0_powerdown_mode.dev_attr.attr, |
| 279 | &iio_dev_attr_out1_powerdown_mode.dev_attr.attr, |
| 280 | &iio_dev_attr_out2_powerdown_mode.dev_attr.attr, |
| 281 | &iio_dev_attr_out3_powerdown_mode.dev_attr.attr, |
| 282 | &iio_const_attr_out_powerdown_mode_available.dev_attr.attr, |
| 283 | NULL, |
| 284 | }; |
| 285 | |
| 286 | static const struct attribute_group ad5686_attribute_group = { |
| 287 | .attrs = ad5686_attributes, |
| 288 | }; |
| 289 | |
| 290 | static int ad5686_read_raw(struct iio_dev *indio_dev, |
| 291 | struct iio_chan_spec const *chan, |
| 292 | int *val, |
| 293 | int *val2, |
| 294 | long m) |
| 295 | { |
| 296 | struct ad5686_state *st = iio_priv(indio_dev); |
| 297 | unsigned long scale_uv; |
| 298 | int ret; |
| 299 | |
| 300 | switch (m) { |
| 301 | case 0: |
| 302 | mutex_lock(&indio_dev->mlock); |
| 303 | ret = ad5686_spi_read(st, chan->address); |
| 304 | mutex_unlock(&indio_dev->mlock); |
| 305 | if (ret < 0) |
| 306 | return ret; |
| 307 | *val = ret; |
| 308 | return IIO_VAL_INT; |
| 309 | break; |
| 310 | case (1 << IIO_CHAN_INFO_SCALE_SHARED): |
| 311 | scale_uv = (st->vref_mv * 100000) |
| 312 | >> (chan->scan_type.realbits); |
| 313 | *val = scale_uv / 100000; |
| 314 | *val2 = (scale_uv % 100000) * 10; |
| 315 | return IIO_VAL_INT_PLUS_MICRO; |
| 316 | |
| 317 | } |
| 318 | return -EINVAL; |
| 319 | } |
| 320 | |
| 321 | static int ad5686_write_raw(struct iio_dev *indio_dev, |
| 322 | struct iio_chan_spec const *chan, |
| 323 | int val, |
| 324 | int val2, |
| 325 | long mask) |
| 326 | { |
| 327 | struct ad5686_state *st = iio_priv(indio_dev); |
| 328 | int ret; |
| 329 | |
| 330 | switch (mask) { |
| 331 | case 0: |
| 332 | if (val > (1 << chan->scan_type.realbits)) |
| 333 | return -EINVAL; |
| 334 | |
| 335 | mutex_lock(&indio_dev->mlock); |
| 336 | ret = ad5686_spi_write(st, |
| 337 | AD5686_CMD_WRITE_INPUT_N_UPDATE_N, |
| 338 | chan->address, |
| 339 | val, |
| 340 | chan->scan_type.shift); |
| 341 | mutex_unlock(&indio_dev->mlock); |
| 342 | break; |
| 343 | default: |
| 344 | ret = -EINVAL; |
| 345 | } |
| 346 | |
| 347 | return ret; |
| 348 | } |
| 349 | |
| 350 | static const struct iio_info ad5686_info = { |
| 351 | .read_raw = ad5686_read_raw, |
| 352 | .write_raw = ad5686_write_raw, |
| 353 | .attrs = &ad5686_attribute_group, |
| 354 | .driver_module = THIS_MODULE, |
| 355 | }; |
| 356 | |
| 357 | static int __devinit ad5686_probe(struct spi_device *spi) |
| 358 | { |
| 359 | struct ad5686_state *st; |
| 360 | struct iio_dev *indio_dev; |
| 361 | int ret, regdone = 0, voltage_uv = 0; |
| 362 | |
| 363 | indio_dev = iio_allocate_device(sizeof(*st)); |
| 364 | if (indio_dev == NULL) |
| 365 | return -ENOMEM; |
| 366 | |
| 367 | st = iio_priv(indio_dev); |
| 368 | spi_set_drvdata(spi, indio_dev); |
| 369 | |
| 370 | st->reg = regulator_get(&spi->dev, "vcc"); |
| 371 | if (!IS_ERR(st->reg)) { |
| 372 | ret = regulator_enable(st->reg); |
| 373 | if (ret) |
| 374 | goto error_put_reg; |
| 375 | |
| 376 | voltage_uv = regulator_get_voltage(st->reg); |
| 377 | } |
| 378 | |
| 379 | st->chip_info = |
| 380 | &ad5686_chip_info_tbl[spi_get_device_id(spi)->driver_data]; |
| 381 | |
| 382 | if (voltage_uv) |
| 383 | st->vref_mv = voltage_uv / 1000; |
| 384 | else |
| 385 | st->vref_mv = st->chip_info->int_vref_mv; |
| 386 | |
| 387 | st->spi = spi; |
| 388 | |
| 389 | indio_dev->dev.parent = &spi->dev; |
| 390 | indio_dev->name = spi_get_device_id(spi)->name; |
| 391 | indio_dev->info = &ad5686_info; |
| 392 | indio_dev->modes = INDIO_DIRECT_MODE; |
| 393 | indio_dev->channels = st->chip_info->channel; |
| 394 | indio_dev->num_channels = AD5686_DAC_CHANNELS; |
| 395 | |
Michael Hennerich | c2f37c8 | 2011-06-10 15:40:49 +0200 | [diff] [blame] | 396 | regdone = 1; |
| 397 | ret = ad5686_spi_write(st, AD5686_CMD_INTERNAL_REFER_SETUP, 0, |
| 398 | !!voltage_uv, 0); |
| 399 | if (ret) |
| 400 | goto error_disable_reg; |
| 401 | |
Jonathan Cameron | 26d25ae | 2011-09-02 17:14:40 +0100 | [diff] [blame^] | 402 | ret = iio_device_register(indio_dev); |
| 403 | if (ret) |
| 404 | goto error_disable_reg; |
| 405 | |
Michael Hennerich | c2f37c8 | 2011-06-10 15:40:49 +0200 | [diff] [blame] | 406 | return 0; |
| 407 | |
| 408 | error_disable_reg: |
| 409 | if (!IS_ERR(st->reg)) |
| 410 | regulator_disable(st->reg); |
| 411 | error_put_reg: |
| 412 | if (!IS_ERR(st->reg)) |
| 413 | regulator_put(st->reg); |
| 414 | |
Jonathan Cameron | 26d25ae | 2011-09-02 17:14:40 +0100 | [diff] [blame^] | 415 | iio_free_device(indio_dev); |
Michael Hennerich | c2f37c8 | 2011-06-10 15:40:49 +0200 | [diff] [blame] | 416 | |
| 417 | return ret; |
| 418 | } |
| 419 | |
| 420 | static int __devexit ad5686_remove(struct spi_device *spi) |
| 421 | { |
| 422 | struct iio_dev *indio_dev = spi_get_drvdata(spi); |
| 423 | struct ad5686_state *st = iio_priv(indio_dev); |
Michael Hennerich | c2f37c8 | 2011-06-10 15:40:49 +0200 | [diff] [blame] | 424 | |
Jonathan Cameron | 26a5479 | 2011-08-30 12:41:19 +0100 | [diff] [blame] | 425 | if (!IS_ERR(st->reg)) { |
| 426 | regulator_disable(st->reg); |
| 427 | regulator_put(st->reg); |
Michael Hennerich | c2f37c8 | 2011-06-10 15:40:49 +0200 | [diff] [blame] | 428 | } |
| 429 | |
| 430 | iio_device_unregister(indio_dev); |
| 431 | |
| 432 | return 0; |
| 433 | } |
| 434 | |
| 435 | static const struct spi_device_id ad5686_id[] = { |
| 436 | {"ad5684", ID_AD5684}, |
| 437 | {"ad5685", ID_AD5685}, |
| 438 | {"ad5686", ID_AD5686}, |
| 439 | {} |
| 440 | }; |
| 441 | |
| 442 | static struct spi_driver ad5686_driver = { |
| 443 | .driver = { |
| 444 | .name = "ad5686", |
| 445 | .owner = THIS_MODULE, |
| 446 | }, |
| 447 | .probe = ad5686_probe, |
| 448 | .remove = __devexit_p(ad5686_remove), |
| 449 | .id_table = ad5686_id, |
| 450 | }; |
| 451 | |
| 452 | static __init int ad5686_spi_init(void) |
| 453 | { |
| 454 | return spi_register_driver(&ad5686_driver); |
| 455 | } |
| 456 | module_init(ad5686_spi_init); |
| 457 | |
| 458 | static __exit void ad5686_spi_exit(void) |
| 459 | { |
| 460 | spi_unregister_driver(&ad5686_driver); |
| 461 | } |
| 462 | module_exit(ad5686_spi_exit); |
| 463 | |
| 464 | MODULE_AUTHOR("Michael Hennerich <hennerich@blackfin.uclinux.org>"); |
| 465 | MODULE_DESCRIPTION("Analog Devices AD5686/85/84 DAC"); |
| 466 | MODULE_LICENSE("GPL v2"); |