1 // SPDX-License-Identifier: GPL-2.0-only 2 /* 3 * ti-dac5571.c - Texas Instruments 8/10/12-bit 1/4-channel DAC driver 4 * 5 * Copyright (C) 2018 Prevas A/S 6 * 7 * https://www.ti.com/lit/ds/symlink/dac5571.pdf 8 * https://www.ti.com/lit/ds/symlink/dac6571.pdf 9 * https://www.ti.com/lit/ds/symlink/dac7571.pdf 10 * https://www.ti.com/lit/ds/symlink/dac5574.pdf 11 * https://www.ti.com/lit/ds/symlink/dac6574.pdf 12 * https://www.ti.com/lit/ds/symlink/dac7574.pdf 13 * https://www.ti.com/lit/ds/symlink/dac5573.pdf 14 * https://www.ti.com/lit/ds/symlink/dac6573.pdf 15 * https://www.ti.com/lit/ds/symlink/dac7573.pdf 16 */ 17 18 #include <linux/iio/iio.h> 19 #include <linux/i2c.h> 20 #include <linux/module.h> 21 #include <linux/of_device.h> 22 #include <linux/of.h> 23 #include <linux/regulator/consumer.h> 24 25 enum chip_id { 26 single_8bit, single_10bit, single_12bit, 27 quad_8bit, quad_10bit, quad_12bit 28 }; 29 30 struct dac5571_spec { 31 u8 num_channels; 32 u8 resolution; 33 }; 34 35 static const struct dac5571_spec dac5571_spec[] = { 36 [single_8bit] = {.num_channels = 1, .resolution = 8}, 37 [single_10bit] = {.num_channels = 1, .resolution = 10}, 38 [single_12bit] = {.num_channels = 1, .resolution = 12}, 39 [quad_8bit] = {.num_channels = 4, .resolution = 8}, 40 [quad_10bit] = {.num_channels = 4, .resolution = 10}, 41 [quad_12bit] = {.num_channels = 4, .resolution = 12}, 42 }; 43 44 struct dac5571_data { 45 struct i2c_client *client; 46 int id; 47 struct mutex lock; 48 struct regulator *vref; 49 u16 val[4]; 50 bool powerdown; 51 u8 powerdown_mode; 52 struct dac5571_spec const *spec; 53 int (*dac5571_cmd)(struct dac5571_data *data, int channel, u16 val); 54 int (*dac5571_pwrdwn)(struct dac5571_data *data, int channel, u8 pwrdwn); 55 u8 buf[3] ____cacheline_aligned; 56 }; 57 58 #define DAC5571_POWERDOWN(mode) ((mode) + 1) 59 #define DAC5571_POWERDOWN_FLAG BIT(0) 60 #define DAC5571_CHANNEL_SELECT 1 61 #define DAC5571_LOADMODE_DIRECT BIT(4) 62 #define DAC5571_SINGLE_PWRDWN_BITS 4 63 #define DAC5571_QUAD_PWRDWN_BITS 6 64 65 static int dac5571_cmd_single(struct dac5571_data *data, int channel, u16 val) 66 { 67 unsigned int shift; 68 69 shift = 12 - data->spec->resolution; 70 data->buf[1] = val << shift; 71 data->buf[0] = val >> (8 - shift); 72 73 if (i2c_master_send(data->client, data->buf, 2) != 2) 74 return -EIO; 75 76 return 0; 77 } 78 79 static int dac5571_cmd_quad(struct dac5571_data *data, int channel, u16 val) 80 { 81 unsigned int shift; 82 83 shift = 16 - data->spec->resolution; 84 data->buf[2] = val << shift; 85 data->buf[1] = (val >> (8 - shift)); 86 data->buf[0] = (channel << DAC5571_CHANNEL_SELECT) | 87 DAC5571_LOADMODE_DIRECT; 88 89 if (i2c_master_send(data->client, data->buf, 3) != 3) 90 return -EIO; 91 92 return 0; 93 } 94 95 static int dac5571_pwrdwn_single(struct dac5571_data *data, int channel, u8 pwrdwn) 96 { 97 data->buf[1] = 0; 98 data->buf[0] = pwrdwn << DAC5571_SINGLE_PWRDWN_BITS; 99 100 if (i2c_master_send(data->client, data->buf, 2) != 2) 101 return -EIO; 102 103 return 0; 104 } 105 106 static int dac5571_pwrdwn_quad(struct dac5571_data *data, int channel, u8 pwrdwn) 107 { 108 data->buf[2] = 0; 109 data->buf[1] = pwrdwn << DAC5571_QUAD_PWRDWN_BITS; 110 data->buf[0] = (channel << DAC5571_CHANNEL_SELECT) | 111 DAC5571_LOADMODE_DIRECT | DAC5571_POWERDOWN_FLAG; 112 113 if (i2c_master_send(data->client, data->buf, 3) != 3) 114 return -EIO; 115 116 return 0; 117 } 118 119 static const char *const dac5571_powerdown_modes[] = { 120 "1kohm_to_gnd", "100kohm_to_gnd", "three_state", 121 }; 122 123 static int dac5571_get_powerdown_mode(struct iio_dev *indio_dev, 124 const struct iio_chan_spec *chan) 125 { 126 struct dac5571_data *data = iio_priv(indio_dev); 127 128 return data->powerdown_mode; 129 } 130 131 static int dac5571_set_powerdown_mode(struct iio_dev *indio_dev, 132 const struct iio_chan_spec *chan, 133 unsigned int mode) 134 { 135 struct dac5571_data *data = iio_priv(indio_dev); 136 int ret = 0; 137 138 if (data->powerdown_mode == mode) 139 return 0; 140 141 mutex_lock(&data->lock); 142 if (data->powerdown) { 143 ret = data->dac5571_pwrdwn(data, chan->channel, 144 DAC5571_POWERDOWN(mode)); 145 if (ret) 146 goto out; 147 } 148 data->powerdown_mode = mode; 149 150 out: 151 mutex_unlock(&data->lock); 152 153 return ret; 154 } 155 156 static const struct iio_enum dac5571_powerdown_mode = { 157 .items = dac5571_powerdown_modes, 158 .num_items = ARRAY_SIZE(dac5571_powerdown_modes), 159 .get = dac5571_get_powerdown_mode, 160 .set = dac5571_set_powerdown_mode, 161 }; 162 163 static ssize_t dac5571_read_powerdown(struct iio_dev *indio_dev, 164 uintptr_t private, 165 const struct iio_chan_spec *chan, 166 char *buf) 167 { 168 struct dac5571_data *data = iio_priv(indio_dev); 169 170 return sprintf(buf, "%d\n", data->powerdown); 171 } 172 173 static ssize_t dac5571_write_powerdown(struct iio_dev *indio_dev, 174 uintptr_t private, 175 const struct iio_chan_spec *chan, 176 const char *buf, size_t len) 177 { 178 struct dac5571_data *data = iio_priv(indio_dev); 179 bool powerdown; 180 int ret; 181 182 ret = strtobool(buf, &powerdown); 183 if (ret) 184 return ret; 185 186 if (data->powerdown == powerdown) 187 return len; 188 189 mutex_lock(&data->lock); 190 if (powerdown) 191 ret = data->dac5571_pwrdwn(data, chan->channel, 192 DAC5571_POWERDOWN(data->powerdown_mode)); 193 else 194 ret = data->dac5571_cmd(data, chan->channel, data->val[0]); 195 if (ret) 196 goto out; 197 198 data->powerdown = powerdown; 199 200 out: 201 mutex_unlock(&data->lock); 202 203 return ret ? ret : len; 204 } 205 206 207 static const struct iio_chan_spec_ext_info dac5571_ext_info[] = { 208 { 209 .name = "powerdown", 210 .read = dac5571_read_powerdown, 211 .write = dac5571_write_powerdown, 212 .shared = IIO_SHARED_BY_TYPE, 213 }, 214 IIO_ENUM("powerdown_mode", IIO_SHARED_BY_TYPE, &dac5571_powerdown_mode), 215 IIO_ENUM_AVAILABLE("powerdown_mode", &dac5571_powerdown_mode), 216 {}, 217 }; 218 219 #define dac5571_CHANNEL(chan, name) { \ 220 .type = IIO_VOLTAGE, \ 221 .channel = (chan), \ 222 .address = (chan), \ 223 .indexed = true, \ 224 .output = true, \ 225 .datasheet_name = name, \ 226 .info_mask_separate = BIT(IIO_CHAN_INFO_RAW), \ 227 .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE), \ 228 .ext_info = dac5571_ext_info, \ 229 } 230 231 static const struct iio_chan_spec dac5571_channels[] = { 232 dac5571_CHANNEL(0, "A"), 233 dac5571_CHANNEL(1, "B"), 234 dac5571_CHANNEL(2, "C"), 235 dac5571_CHANNEL(3, "D"), 236 }; 237 238 static int dac5571_read_raw(struct iio_dev *indio_dev, 239 struct iio_chan_spec const *chan, 240 int *val, int *val2, long mask) 241 { 242 struct dac5571_data *data = iio_priv(indio_dev); 243 int ret; 244 245 switch (mask) { 246 case IIO_CHAN_INFO_RAW: 247 *val = data->val[chan->channel]; 248 return IIO_VAL_INT; 249 250 case IIO_CHAN_INFO_SCALE: 251 ret = regulator_get_voltage(data->vref); 252 if (ret < 0) 253 return ret; 254 255 *val = ret / 1000; 256 *val2 = data->spec->resolution; 257 return IIO_VAL_FRACTIONAL_LOG2; 258 259 default: 260 return -EINVAL; 261 } 262 } 263 264 static int dac5571_write_raw(struct iio_dev *indio_dev, 265 struct iio_chan_spec const *chan, 266 int val, int val2, long mask) 267 { 268 struct dac5571_data *data = iio_priv(indio_dev); 269 int ret; 270 271 switch (mask) { 272 case IIO_CHAN_INFO_RAW: 273 if (data->val[chan->channel] == val) 274 return 0; 275 276 if (val >= (1 << data->spec->resolution) || val < 0) 277 return -EINVAL; 278 279 if (data->powerdown) 280 return -EBUSY; 281 282 mutex_lock(&data->lock); 283 ret = data->dac5571_cmd(data, chan->channel, val); 284 if (ret == 0) 285 data->val[chan->channel] = val; 286 mutex_unlock(&data->lock); 287 return ret; 288 289 default: 290 return -EINVAL; 291 } 292 } 293 294 static int dac5571_write_raw_get_fmt(struct iio_dev *indio_dev, 295 struct iio_chan_spec const *chan, 296 long mask) 297 { 298 return IIO_VAL_INT; 299 } 300 301 static const struct iio_info dac5571_info = { 302 .read_raw = dac5571_read_raw, 303 .write_raw = dac5571_write_raw, 304 .write_raw_get_fmt = dac5571_write_raw_get_fmt, 305 }; 306 307 static int dac5571_probe(struct i2c_client *client, 308 const struct i2c_device_id *id) 309 { 310 struct device *dev = &client->dev; 311 const struct dac5571_spec *spec; 312 struct dac5571_data *data; 313 struct iio_dev *indio_dev; 314 int ret, i; 315 316 indio_dev = devm_iio_device_alloc(dev, sizeof(*data)); 317 if (!indio_dev) 318 return -ENOMEM; 319 320 data = iio_priv(indio_dev); 321 i2c_set_clientdata(client, indio_dev); 322 data->client = client; 323 324 indio_dev->info = &dac5571_info; 325 indio_dev->name = id->name; 326 indio_dev->modes = INDIO_DIRECT_MODE; 327 indio_dev->channels = dac5571_channels; 328 329 spec = &dac5571_spec[id->driver_data]; 330 indio_dev->num_channels = spec->num_channels; 331 data->spec = spec; 332 333 data->vref = devm_regulator_get(dev, "vref"); 334 if (IS_ERR(data->vref)) 335 return PTR_ERR(data->vref); 336 337 ret = regulator_enable(data->vref); 338 if (ret < 0) 339 return ret; 340 341 mutex_init(&data->lock); 342 343 switch (spec->num_channels) { 344 case 1: 345 data->dac5571_cmd = dac5571_cmd_single; 346 data->dac5571_pwrdwn = dac5571_pwrdwn_single; 347 break; 348 case 4: 349 data->dac5571_cmd = dac5571_cmd_quad; 350 data->dac5571_pwrdwn = dac5571_pwrdwn_quad; 351 break; 352 default: 353 goto err; 354 } 355 356 for (i = 0; i < spec->num_channels; i++) { 357 ret = data->dac5571_cmd(data, i, 0); 358 if (ret) { 359 dev_err(dev, "failed to initialize channel %d to 0\n", i); 360 goto err; 361 } 362 } 363 364 ret = iio_device_register(indio_dev); 365 if (ret) 366 goto err; 367 368 return 0; 369 370 err: 371 regulator_disable(data->vref); 372 return ret; 373 } 374 375 static int dac5571_remove(struct i2c_client *i2c) 376 { 377 struct iio_dev *indio_dev = i2c_get_clientdata(i2c); 378 struct dac5571_data *data = iio_priv(indio_dev); 379 380 iio_device_unregister(indio_dev); 381 regulator_disable(data->vref); 382 383 return 0; 384 } 385 386 #ifdef CONFIG_OF 387 static const struct of_device_id dac5571_of_id[] = { 388 {.compatible = "ti,dac5571"}, 389 {.compatible = "ti,dac6571"}, 390 {.compatible = "ti,dac7571"}, 391 {.compatible = "ti,dac5574"}, 392 {.compatible = "ti,dac6574"}, 393 {.compatible = "ti,dac7574"}, 394 {.compatible = "ti,dac5573"}, 395 {.compatible = "ti,dac6573"}, 396 {.compatible = "ti,dac7573"}, 397 {} 398 }; 399 MODULE_DEVICE_TABLE(of, dac5571_of_id); 400 #endif 401 402 static const struct i2c_device_id dac5571_id[] = { 403 {"dac5571", single_8bit}, 404 {"dac6571", single_10bit}, 405 {"dac7571", single_12bit}, 406 {"dac5574", quad_8bit}, 407 {"dac6574", quad_10bit}, 408 {"dac7574", quad_12bit}, 409 {"dac5573", quad_8bit}, 410 {"dac6573", quad_10bit}, 411 {"dac7573", quad_12bit}, 412 {} 413 }; 414 MODULE_DEVICE_TABLE(i2c, dac5571_id); 415 416 static struct i2c_driver dac5571_driver = { 417 .driver = { 418 .name = "ti-dac5571", 419 .of_match_table = of_match_ptr(dac5571_of_id), 420 }, 421 .probe = dac5571_probe, 422 .remove = dac5571_remove, 423 .id_table = dac5571_id, 424 }; 425 module_i2c_driver(dac5571_driver); 426 427 MODULE_AUTHOR("Sean Nyekjaer <sean@geanix.dk>"); 428 MODULE_DESCRIPTION("Texas Instruments 8/10/12-bit 1/4-channel DAC driver"); 429 MODULE_LICENSE("GPL v2"); 430