1 // SPDX-License-Identifier: GPL-2.0-only 2 /* 3 * AD5504, AD5501 High Voltage Digital to Analog Converter 4 * 5 * Copyright 2011 Analog Devices Inc. 6 */ 7 8 #include <linux/interrupt.h> 9 #include <linux/fs.h> 10 #include <linux/device.h> 11 #include <linux/kernel.h> 12 #include <linux/spi/spi.h> 13 #include <linux/slab.h> 14 #include <linux/sysfs.h> 15 #include <linux/regulator/consumer.h> 16 #include <linux/module.h> 17 #include <linux/bitops.h> 18 19 #include <linux/iio/iio.h> 20 #include <linux/iio/sysfs.h> 21 #include <linux/iio/events.h> 22 #include <linux/iio/dac/ad5504.h> 23 24 #define AD5504_RES_MASK GENMASK(11, 0) 25 #define AD5504_CMD_READ BIT(15) 26 #define AD5504_CMD_WRITE 0 27 #define AD5504_ADDR(addr) ((addr) << 12) 28 29 /* Registers */ 30 #define AD5504_ADDR_NOOP 0 31 #define AD5504_ADDR_DAC(x) ((x) + 1) 32 #define AD5504_ADDR_ALL_DAC 5 33 #define AD5504_ADDR_CTRL 7 34 35 /* Control Register */ 36 #define AD5504_DAC_PWR(ch) ((ch) << 2) 37 #define AD5504_DAC_PWRDWN_MODE(mode) ((mode) << 6) 38 #define AD5504_DAC_PWRDN_20K 0 39 #define AD5504_DAC_PWRDN_3STATE 1 40 41 /** 42 * struct ad5446_state - driver instance specific data 43 * @spi: spi_device 44 * @reg: supply regulator 45 * @vref_mv: actual reference voltage used 46 * @pwr_down_mask power down mask 47 * @pwr_down_mode current power down mode 48 * @data: transfer buffer 49 */ 50 struct ad5504_state { 51 struct spi_device *spi; 52 struct regulator *reg; 53 unsigned short vref_mv; 54 unsigned pwr_down_mask; 55 unsigned pwr_down_mode; 56 57 __be16 data[2] ____cacheline_aligned; 58 }; 59 60 /** 61 * ad5504_supported_device_ids: 62 */ 63 64 enum ad5504_supported_device_ids { 65 ID_AD5504, 66 ID_AD5501, 67 }; 68 69 static int ad5504_spi_write(struct ad5504_state *st, u8 addr, u16 val) 70 { 71 st->data[0] = cpu_to_be16(AD5504_CMD_WRITE | AD5504_ADDR(addr) | 72 (val & AD5504_RES_MASK)); 73 74 return spi_write(st->spi, &st->data[0], 2); 75 } 76 77 static int ad5504_spi_read(struct ad5504_state *st, u8 addr) 78 { 79 int ret; 80 struct spi_transfer t = { 81 .tx_buf = &st->data[0], 82 .rx_buf = &st->data[1], 83 .len = 2, 84 }; 85 86 st->data[0] = cpu_to_be16(AD5504_CMD_READ | AD5504_ADDR(addr)); 87 ret = spi_sync_transfer(st->spi, &t, 1); 88 if (ret < 0) 89 return ret; 90 91 return be16_to_cpu(st->data[1]) & AD5504_RES_MASK; 92 } 93 94 static int ad5504_read_raw(struct iio_dev *indio_dev, 95 struct iio_chan_spec const *chan, 96 int *val, 97 int *val2, 98 long m) 99 { 100 struct ad5504_state *st = iio_priv(indio_dev); 101 int ret; 102 103 switch (m) { 104 case IIO_CHAN_INFO_RAW: 105 ret = ad5504_spi_read(st, chan->address); 106 if (ret < 0) 107 return ret; 108 109 *val = ret; 110 111 return IIO_VAL_INT; 112 case IIO_CHAN_INFO_SCALE: 113 *val = st->vref_mv; 114 *val2 = chan->scan_type.realbits; 115 return IIO_VAL_FRACTIONAL_LOG2; 116 } 117 return -EINVAL; 118 } 119 120 static int ad5504_write_raw(struct iio_dev *indio_dev, 121 struct iio_chan_spec const *chan, 122 int val, 123 int val2, 124 long mask) 125 { 126 struct ad5504_state *st = iio_priv(indio_dev); 127 128 switch (mask) { 129 case IIO_CHAN_INFO_RAW: 130 if (val >= (1 << chan->scan_type.realbits) || val < 0) 131 return -EINVAL; 132 133 return ad5504_spi_write(st, chan->address, val); 134 default: 135 return -EINVAL; 136 } 137 } 138 139 static const char * const ad5504_powerdown_modes[] = { 140 "20kohm_to_gnd", 141 "three_state", 142 }; 143 144 static int ad5504_get_powerdown_mode(struct iio_dev *indio_dev, 145 const struct iio_chan_spec *chan) 146 { 147 struct ad5504_state *st = iio_priv(indio_dev); 148 149 return st->pwr_down_mode; 150 } 151 152 static int ad5504_set_powerdown_mode(struct iio_dev *indio_dev, 153 const struct iio_chan_spec *chan, unsigned int mode) 154 { 155 struct ad5504_state *st = iio_priv(indio_dev); 156 157 st->pwr_down_mode = mode; 158 159 return 0; 160 } 161 162 static const struct iio_enum ad5504_powerdown_mode_enum = { 163 .items = ad5504_powerdown_modes, 164 .num_items = ARRAY_SIZE(ad5504_powerdown_modes), 165 .get = ad5504_get_powerdown_mode, 166 .set = ad5504_set_powerdown_mode, 167 }; 168 169 static ssize_t ad5504_read_dac_powerdown(struct iio_dev *indio_dev, 170 uintptr_t private, const struct iio_chan_spec *chan, char *buf) 171 { 172 struct ad5504_state *st = iio_priv(indio_dev); 173 174 return sprintf(buf, "%d\n", 175 !(st->pwr_down_mask & (1 << chan->channel))); 176 } 177 178 static ssize_t ad5504_write_dac_powerdown(struct iio_dev *indio_dev, 179 uintptr_t private, const struct iio_chan_spec *chan, const char *buf, 180 size_t len) 181 { 182 bool pwr_down; 183 int ret; 184 struct ad5504_state *st = iio_priv(indio_dev); 185 186 ret = strtobool(buf, &pwr_down); 187 if (ret) 188 return ret; 189 190 if (pwr_down) 191 st->pwr_down_mask |= (1 << chan->channel); 192 else 193 st->pwr_down_mask &= ~(1 << chan->channel); 194 195 ret = ad5504_spi_write(st, AD5504_ADDR_CTRL, 196 AD5504_DAC_PWRDWN_MODE(st->pwr_down_mode) | 197 AD5504_DAC_PWR(st->pwr_down_mask)); 198 199 /* writes to the CTRL register must be followed by a NOOP */ 200 ad5504_spi_write(st, AD5504_ADDR_NOOP, 0); 201 202 return ret ? ret : len; 203 } 204 205 static IIO_CONST_ATTR(temp0_thresh_rising_value, "110000"); 206 static IIO_CONST_ATTR(temp0_thresh_rising_en, "1"); 207 208 static struct attribute *ad5504_ev_attributes[] = { 209 &iio_const_attr_temp0_thresh_rising_value.dev_attr.attr, 210 &iio_const_attr_temp0_thresh_rising_en.dev_attr.attr, 211 NULL, 212 }; 213 214 static const struct attribute_group ad5504_ev_attribute_group = { 215 .attrs = ad5504_ev_attributes, 216 }; 217 218 static irqreturn_t ad5504_event_handler(int irq, void *private) 219 { 220 iio_push_event(private, 221 IIO_UNMOD_EVENT_CODE(IIO_TEMP, 222 0, 223 IIO_EV_TYPE_THRESH, 224 IIO_EV_DIR_RISING), 225 iio_get_time_ns(private)); 226 227 return IRQ_HANDLED; 228 } 229 230 static const struct iio_info ad5504_info = { 231 .write_raw = ad5504_write_raw, 232 .read_raw = ad5504_read_raw, 233 .event_attrs = &ad5504_ev_attribute_group, 234 }; 235 236 static const struct iio_chan_spec_ext_info ad5504_ext_info[] = { 237 { 238 .name = "powerdown", 239 .read = ad5504_read_dac_powerdown, 240 .write = ad5504_write_dac_powerdown, 241 .shared = IIO_SEPARATE, 242 }, 243 IIO_ENUM("powerdown_mode", IIO_SHARED_BY_TYPE, 244 &ad5504_powerdown_mode_enum), 245 IIO_ENUM_AVAILABLE("powerdown_mode", &ad5504_powerdown_mode_enum), 246 { }, 247 }; 248 249 #define AD5504_CHANNEL(_chan) { \ 250 .type = IIO_VOLTAGE, \ 251 .indexed = 1, \ 252 .output = 1, \ 253 .channel = (_chan), \ 254 .info_mask_separate = BIT(IIO_CHAN_INFO_RAW), \ 255 .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE), \ 256 .address = AD5504_ADDR_DAC(_chan), \ 257 .scan_type = { \ 258 .sign = 'u', \ 259 .realbits = 12, \ 260 .storagebits = 16, \ 261 }, \ 262 .ext_info = ad5504_ext_info, \ 263 } 264 265 static const struct iio_chan_spec ad5504_channels[] = { 266 AD5504_CHANNEL(0), 267 AD5504_CHANNEL(1), 268 AD5504_CHANNEL(2), 269 AD5504_CHANNEL(3), 270 }; 271 272 static int ad5504_probe(struct spi_device *spi) 273 { 274 struct ad5504_platform_data *pdata = spi->dev.platform_data; 275 struct iio_dev *indio_dev; 276 struct ad5504_state *st; 277 struct regulator *reg; 278 int ret, voltage_uv = 0; 279 280 indio_dev = devm_iio_device_alloc(&spi->dev, sizeof(*st)); 281 if (!indio_dev) 282 return -ENOMEM; 283 reg = devm_regulator_get(&spi->dev, "vcc"); 284 if (!IS_ERR(reg)) { 285 ret = regulator_enable(reg); 286 if (ret) 287 return ret; 288 289 ret = regulator_get_voltage(reg); 290 if (ret < 0) 291 goto error_disable_reg; 292 293 voltage_uv = ret; 294 } 295 296 spi_set_drvdata(spi, indio_dev); 297 st = iio_priv(indio_dev); 298 if (voltage_uv) 299 st->vref_mv = voltage_uv / 1000; 300 else if (pdata) 301 st->vref_mv = pdata->vref_mv; 302 else 303 dev_warn(&spi->dev, "reference voltage unspecified\n"); 304 305 st->reg = reg; 306 st->spi = spi; 307 indio_dev->dev.parent = &spi->dev; 308 indio_dev->name = spi_get_device_id(st->spi)->name; 309 indio_dev->info = &ad5504_info; 310 if (spi_get_device_id(st->spi)->driver_data == ID_AD5501) 311 indio_dev->num_channels = 1; 312 else 313 indio_dev->num_channels = 4; 314 indio_dev->channels = ad5504_channels; 315 indio_dev->modes = INDIO_DIRECT_MODE; 316 317 if (spi->irq) { 318 ret = devm_request_threaded_irq(&spi->dev, spi->irq, 319 NULL, 320 &ad5504_event_handler, 321 IRQF_TRIGGER_FALLING | IRQF_ONESHOT, 322 spi_get_device_id(st->spi)->name, 323 indio_dev); 324 if (ret) 325 goto error_disable_reg; 326 } 327 328 ret = iio_device_register(indio_dev); 329 if (ret) 330 goto error_disable_reg; 331 332 return 0; 333 334 error_disable_reg: 335 if (!IS_ERR(reg)) 336 regulator_disable(reg); 337 338 return ret; 339 } 340 341 static int ad5504_remove(struct spi_device *spi) 342 { 343 struct iio_dev *indio_dev = spi_get_drvdata(spi); 344 struct ad5504_state *st = iio_priv(indio_dev); 345 346 iio_device_unregister(indio_dev); 347 348 if (!IS_ERR(st->reg)) 349 regulator_disable(st->reg); 350 351 return 0; 352 } 353 354 static const struct spi_device_id ad5504_id[] = { 355 {"ad5504", ID_AD5504}, 356 {"ad5501", ID_AD5501}, 357 {} 358 }; 359 MODULE_DEVICE_TABLE(spi, ad5504_id); 360 361 static struct spi_driver ad5504_driver = { 362 .driver = { 363 .name = "ad5504", 364 }, 365 .probe = ad5504_probe, 366 .remove = ad5504_remove, 367 .id_table = ad5504_id, 368 }; 369 module_spi_driver(ad5504_driver); 370 371 MODULE_AUTHOR("Michael Hennerich <michael.hennerich@analog.com>"); 372 MODULE_DESCRIPTION("Analog Devices AD5501/AD5501 DAC"); 373 MODULE_LICENSE("GPL v2"); 374