1 /* 2 * ti-dac5571.c - Texas Instruments 8/10/12-bit 1/4-channel DAC driver 3 * 4 * Copyright (C) 2018 Prevas A/S 5 * 6 * http://www.ti.com/lit/ds/symlink/dac5571.pdf 7 * http://www.ti.com/lit/ds/symlink/dac6571.pdf 8 * http://www.ti.com/lit/ds/symlink/dac7571.pdf 9 * http://www.ti.com/lit/ds/symlink/dac5574.pdf 10 * http://www.ti.com/lit/ds/symlink/dac6574.pdf 11 * http://www.ti.com/lit/ds/symlink/dac7574.pdf 12 * http://www.ti.com/lit/ds/symlink/dac5573.pdf 13 * http://www.ti.com/lit/ds/symlink/dac6573.pdf 14 * http://www.ti.com/lit/ds/symlink/dac7573.pdf 15 * 16 * This program is free software; you can redistribute it and/or modify 17 * it under the terms of the GNU General Public License (version 2) as 18 * published by the Free Software Foundation. 19 */ 20 21 #include <linux/iio/iio.h> 22 #include <linux/i2c.h> 23 #include <linux/module.h> 24 #include <linux/of_device.h> 25 #include <linux/of.h> 26 #include <linux/regulator/consumer.h> 27 28 enum chip_id { 29 single_8bit, single_10bit, single_12bit, 30 quad_8bit, quad_10bit, quad_12bit 31 }; 32 33 struct dac5571_spec { 34 u8 num_channels; 35 u8 resolution; 36 }; 37 38 static const struct dac5571_spec dac5571_spec[] = { 39 [single_8bit] = {.num_channels = 1, .resolution = 8}, 40 [single_10bit] = {.num_channels = 1, .resolution = 10}, 41 [single_12bit] = {.num_channels = 1, .resolution = 12}, 42 [quad_8bit] = {.num_channels = 4, .resolution = 8}, 43 [quad_10bit] = {.num_channels = 4, .resolution = 10}, 44 [quad_12bit] = {.num_channels = 4, .resolution = 12}, 45 }; 46 47 struct dac5571_data { 48 struct i2c_client *client; 49 int id; 50 struct mutex lock; 51 struct regulator *vref; 52 u16 val[4]; 53 bool powerdown; 54 u8 powerdown_mode; 55 struct dac5571_spec const *spec; 56 int (*dac5571_cmd)(struct dac5571_data *data, int channel, u16 val); 57 int (*dac5571_pwrdwn)(struct dac5571_data *data, int channel, u8 pwrdwn); 58 u8 buf[3] ____cacheline_aligned; 59 }; 60 61 #define DAC5571_POWERDOWN(mode) ((mode) + 1) 62 #define DAC5571_POWERDOWN_FLAG BIT(0) 63 #define DAC5571_CHANNEL_SELECT 1 64 #define DAC5571_LOADMODE_DIRECT BIT(4) 65 #define DAC5571_SINGLE_PWRDWN_BITS 4 66 #define DAC5571_QUAD_PWRDWN_BITS 6 67 68 static int dac5571_cmd_single(struct dac5571_data *data, int channel, u16 val) 69 { 70 unsigned int shift; 71 72 shift = 12 - data->spec->resolution; 73 data->buf[1] = val << shift; 74 data->buf[0] = val >> (8 - shift); 75 76 if (i2c_master_send(data->client, data->buf, 2) != 2) 77 return -EIO; 78 79 return 0; 80 } 81 82 static int dac5571_cmd_quad(struct dac5571_data *data, int channel, u16 val) 83 { 84 unsigned int shift; 85 86 shift = 16 - data->spec->resolution; 87 data->buf[2] = val << shift; 88 data->buf[1] = (val >> (8 - shift)); 89 data->buf[0] = (channel << DAC5571_CHANNEL_SELECT) | 90 DAC5571_LOADMODE_DIRECT; 91 92 if (i2c_master_send(data->client, data->buf, 3) != 3) 93 return -EIO; 94 95 return 0; 96 } 97 98 static int dac5571_pwrdwn_single(struct dac5571_data *data, int channel, u8 pwrdwn) 99 { 100 data->buf[1] = 0; 101 data->buf[0] = pwrdwn << DAC5571_SINGLE_PWRDWN_BITS; 102 103 if (i2c_master_send(data->client, data->buf, 2) != 2) 104 return -EIO; 105 106 return 0; 107 } 108 109 static int dac5571_pwrdwn_quad(struct dac5571_data *data, int channel, u8 pwrdwn) 110 { 111 data->buf[2] = 0; 112 data->buf[1] = pwrdwn << DAC5571_QUAD_PWRDWN_BITS; 113 data->buf[0] = (channel << DAC5571_CHANNEL_SELECT) | 114 DAC5571_LOADMODE_DIRECT | DAC5571_POWERDOWN_FLAG; 115 116 if (i2c_master_send(data->client, data->buf, 3) != 3) 117 return -EIO; 118 119 return 0; 120 } 121 122 static const char *const dac5571_powerdown_modes[] = { 123 "1kohm_to_gnd", "100kohm_to_gnd", "three_state", 124 }; 125 126 static int dac5571_get_powerdown_mode(struct iio_dev *indio_dev, 127 const struct iio_chan_spec *chan) 128 { 129 struct dac5571_data *data = iio_priv(indio_dev); 130 131 return data->powerdown_mode; 132 } 133 134 static int dac5571_set_powerdown_mode(struct iio_dev *indio_dev, 135 const struct iio_chan_spec *chan, 136 unsigned int mode) 137 { 138 struct dac5571_data *data = iio_priv(indio_dev); 139 int ret = 0; 140 141 if (data->powerdown_mode == mode) 142 return 0; 143 144 mutex_lock(&data->lock); 145 if (data->powerdown) { 146 ret = data->dac5571_pwrdwn(data, chan->channel, 147 DAC5571_POWERDOWN(mode)); 148 if (ret) 149 goto out; 150 } 151 data->powerdown_mode = mode; 152 153 out: 154 mutex_unlock(&data->lock); 155 156 return ret; 157 } 158 159 static const struct iio_enum dac5571_powerdown_mode = { 160 .items = dac5571_powerdown_modes, 161 .num_items = ARRAY_SIZE(dac5571_powerdown_modes), 162 .get = dac5571_get_powerdown_mode, 163 .set = dac5571_set_powerdown_mode, 164 }; 165 166 static ssize_t dac5571_read_powerdown(struct iio_dev *indio_dev, 167 uintptr_t private, 168 const struct iio_chan_spec *chan, 169 char *buf) 170 { 171 struct dac5571_data *data = iio_priv(indio_dev); 172 173 return sprintf(buf, "%d\n", data->powerdown); 174 } 175 176 static ssize_t dac5571_write_powerdown(struct iio_dev *indio_dev, 177 uintptr_t private, 178 const struct iio_chan_spec *chan, 179 const char *buf, size_t len) 180 { 181 struct dac5571_data *data = iio_priv(indio_dev); 182 bool powerdown; 183 int ret; 184 185 ret = strtobool(buf, &powerdown); 186 if (ret) 187 return ret; 188 189 if (data->powerdown == powerdown) 190 return len; 191 192 mutex_lock(&data->lock); 193 if (powerdown) 194 ret = data->dac5571_pwrdwn(data, chan->channel, 195 DAC5571_POWERDOWN(data->powerdown_mode)); 196 else 197 ret = data->dac5571_cmd(data, chan->channel, data->val[0]); 198 if (ret) 199 goto out; 200 201 data->powerdown = powerdown; 202 203 out: 204 mutex_unlock(&data->lock); 205 206 return ret ? ret : len; 207 } 208 209 210 static const struct iio_chan_spec_ext_info dac5571_ext_info[] = { 211 { 212 .name = "powerdown", 213 .read = dac5571_read_powerdown, 214 .write = dac5571_write_powerdown, 215 .shared = IIO_SHARED_BY_TYPE, 216 }, 217 IIO_ENUM("powerdown_mode", IIO_SHARED_BY_TYPE, &dac5571_powerdown_mode), 218 IIO_ENUM_AVAILABLE("powerdown_mode", &dac5571_powerdown_mode), 219 {}, 220 }; 221 222 #define dac5571_CHANNEL(chan, name) { \ 223 .type = IIO_VOLTAGE, \ 224 .channel = (chan), \ 225 .address = (chan), \ 226 .indexed = true, \ 227 .output = true, \ 228 .datasheet_name = name, \ 229 .info_mask_separate = BIT(IIO_CHAN_INFO_RAW), \ 230 .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE), \ 231 .ext_info = dac5571_ext_info, \ 232 } 233 234 static const struct iio_chan_spec dac5571_channels[] = { 235 dac5571_CHANNEL(0, "A"), 236 dac5571_CHANNEL(1, "B"), 237 dac5571_CHANNEL(2, "C"), 238 dac5571_CHANNEL(3, "D"), 239 }; 240 241 static int dac5571_read_raw(struct iio_dev *indio_dev, 242 struct iio_chan_spec const *chan, 243 int *val, int *val2, long mask) 244 { 245 struct dac5571_data *data = iio_priv(indio_dev); 246 int ret; 247 248 switch (mask) { 249 case IIO_CHAN_INFO_RAW: 250 *val = data->val[chan->channel]; 251 return IIO_VAL_INT; 252 253 case IIO_CHAN_INFO_SCALE: 254 ret = regulator_get_voltage(data->vref); 255 if (ret < 0) 256 return ret; 257 258 *val = ret / 1000; 259 *val2 = data->spec->resolution; 260 return IIO_VAL_FRACTIONAL_LOG2; 261 262 default: 263 return -EINVAL; 264 } 265 } 266 267 static int dac5571_write_raw(struct iio_dev *indio_dev, 268 struct iio_chan_spec const *chan, 269 int val, int val2, long mask) 270 { 271 struct dac5571_data *data = iio_priv(indio_dev); 272 int ret; 273 274 switch (mask) { 275 case IIO_CHAN_INFO_RAW: 276 if (data->val[chan->channel] == val) 277 return 0; 278 279 if (val >= (1 << data->spec->resolution) || val < 0) 280 return -EINVAL; 281 282 if (data->powerdown) 283 return -EBUSY; 284 285 mutex_lock(&data->lock); 286 ret = data->dac5571_cmd(data, chan->channel, val); 287 if (ret == 0) 288 data->val[chan->channel] = val; 289 mutex_unlock(&data->lock); 290 return ret; 291 292 default: 293 return -EINVAL; 294 } 295 } 296 297 static int dac5571_write_raw_get_fmt(struct iio_dev *indio_dev, 298 struct iio_chan_spec const *chan, 299 long mask) 300 { 301 return IIO_VAL_INT; 302 } 303 304 static const struct iio_info dac5571_info = { 305 .read_raw = dac5571_read_raw, 306 .write_raw = dac5571_write_raw, 307 .write_raw_get_fmt = dac5571_write_raw_get_fmt, 308 }; 309 310 static int dac5571_probe(struct i2c_client *client, 311 const struct i2c_device_id *id) 312 { 313 struct device *dev = &client->dev; 314 const struct dac5571_spec *spec; 315 struct dac5571_data *data; 316 struct iio_dev *indio_dev; 317 int ret, i; 318 319 indio_dev = devm_iio_device_alloc(dev, sizeof(*data)); 320 if (!indio_dev) 321 return -ENOMEM; 322 323 data = iio_priv(indio_dev); 324 i2c_set_clientdata(client, indio_dev); 325 data->client = client; 326 327 indio_dev->dev.parent = dev; 328 indio_dev->dev.of_node = client->dev.of_node; 329 indio_dev->info = &dac5571_info; 330 indio_dev->name = id->name; 331 indio_dev->modes = INDIO_DIRECT_MODE; 332 indio_dev->channels = dac5571_channels; 333 334 spec = &dac5571_spec[id->driver_data]; 335 indio_dev->num_channels = spec->num_channels; 336 data->spec = spec; 337 338 data->vref = devm_regulator_get(dev, "vref"); 339 if (IS_ERR(data->vref)) 340 return PTR_ERR(data->vref); 341 342 ret = regulator_enable(data->vref); 343 if (ret < 0) 344 return ret; 345 346 mutex_init(&data->lock); 347 348 switch (spec->num_channels) { 349 case 1: 350 data->dac5571_cmd = dac5571_cmd_single; 351 data->dac5571_pwrdwn = dac5571_pwrdwn_single; 352 break; 353 case 4: 354 data->dac5571_cmd = dac5571_cmd_quad; 355 data->dac5571_pwrdwn = dac5571_pwrdwn_quad; 356 break; 357 default: 358 goto err; 359 } 360 361 for (i = 0; i < spec->num_channels; i++) { 362 ret = data->dac5571_cmd(data, i, 0); 363 if (ret) { 364 dev_err(dev, "failed to initialize channel %d to 0\n", i); 365 goto err; 366 } 367 } 368 369 ret = iio_device_register(indio_dev); 370 if (ret) 371 goto err; 372 373 return 0; 374 375 err: 376 regulator_disable(data->vref); 377 return ret; 378 } 379 380 static int dac5571_remove(struct i2c_client *i2c) 381 { 382 struct iio_dev *indio_dev = i2c_get_clientdata(i2c); 383 struct dac5571_data *data = iio_priv(indio_dev); 384 385 iio_device_unregister(indio_dev); 386 regulator_disable(data->vref); 387 388 return 0; 389 } 390 391 #ifdef CONFIG_OF 392 static const struct of_device_id dac5571_of_id[] = { 393 {.compatible = "ti,dac5571"}, 394 {.compatible = "ti,dac6571"}, 395 {.compatible = "ti,dac7571"}, 396 {.compatible = "ti,dac5574"}, 397 {.compatible = "ti,dac6574"}, 398 {.compatible = "ti,dac7574"}, 399 {.compatible = "ti,dac5573"}, 400 {.compatible = "ti,dac6573"}, 401 {.compatible = "ti,dac7573"}, 402 {} 403 }; 404 MODULE_DEVICE_TABLE(of, dac5571_of_id); 405 #endif 406 407 static const struct i2c_device_id dac5571_id[] = { 408 {"dac5571", single_8bit}, 409 {"dac6571", single_10bit}, 410 {"dac7571", single_12bit}, 411 {"dac5574", quad_8bit}, 412 {"dac6574", quad_10bit}, 413 {"dac7574", quad_12bit}, 414 {"dac5573", quad_8bit}, 415 {"dac6573", quad_10bit}, 416 {"dac7573", quad_12bit}, 417 {} 418 }; 419 MODULE_DEVICE_TABLE(i2c, dac5571_id); 420 421 static struct i2c_driver dac5571_driver = { 422 .driver = { 423 .name = "ti-dac5571", 424 .of_match_table = of_match_ptr(dac5571_of_id), 425 }, 426 .probe = dac5571_probe, 427 .remove = dac5571_remove, 428 .id_table = dac5571_id, 429 }; 430 module_i2c_driver(dac5571_driver); 431 432 MODULE_AUTHOR("Sean Nyekjaer <sean.nyekjaer@prevas.dk>"); 433 MODULE_DESCRIPTION("Texas Instruments 8/10/12-bit 1/4-channel DAC driver"); 434 MODULE_LICENSE("GPL v2"); 435