1 // SPDX-License-Identifier: GPL-2.0-only 2 /* 3 * AD5624R, AD5644R, AD5664R Digital to analog convertors spi driver 4 * 5 * Copyright 2010-2011 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 18 #include <linux/iio/iio.h> 19 #include <linux/iio/sysfs.h> 20 21 #include <asm/unaligned.h> 22 23 #include "ad5624r.h" 24 25 static int ad5624r_spi_write(struct spi_device *spi, 26 u8 cmd, u8 addr, u16 val, u8 shift) 27 { 28 u32 data; 29 u8 msg[3]; 30 31 /* 32 * The input shift register is 24 bits wide. The first two bits are 33 * don't care bits. The next three are the command bits, C2 to C0, 34 * followed by the 3-bit DAC address, A2 to A0, and then the 35 * 16-, 14-, 12-bit data-word. The data-word comprises the 16-, 36 * 14-, 12-bit input code followed by 0, 2, or 4 don't care bits, 37 * for the AD5664R, AD5644R, and AD5624R, respectively. 38 */ 39 data = (0 << 22) | (cmd << 19) | (addr << 16) | (val << shift); 40 put_unaligned_be24(data, &msg[0]); 41 42 return spi_write(spi, msg, sizeof(msg)); 43 } 44 45 static int ad5624r_read_raw(struct iio_dev *indio_dev, 46 struct iio_chan_spec const *chan, 47 int *val, 48 int *val2, 49 long m) 50 { 51 struct ad5624r_state *st = iio_priv(indio_dev); 52 53 switch (m) { 54 case IIO_CHAN_INFO_SCALE: 55 *val = st->vref_mv; 56 *val2 = chan->scan_type.realbits; 57 return IIO_VAL_FRACTIONAL_LOG2; 58 } 59 return -EINVAL; 60 } 61 62 static int ad5624r_write_raw(struct iio_dev *indio_dev, 63 struct iio_chan_spec const *chan, 64 int val, 65 int val2, 66 long mask) 67 { 68 struct ad5624r_state *st = iio_priv(indio_dev); 69 70 switch (mask) { 71 case IIO_CHAN_INFO_RAW: 72 if (val >= (1 << chan->scan_type.realbits) || val < 0) 73 return -EINVAL; 74 75 return ad5624r_spi_write(st->us, 76 AD5624R_CMD_WRITE_INPUT_N_UPDATE_N, 77 chan->address, val, 78 chan->scan_type.shift); 79 default: 80 return -EINVAL; 81 } 82 } 83 84 static const char * const ad5624r_powerdown_modes[] = { 85 "1kohm_to_gnd", 86 "100kohm_to_gnd", 87 "three_state" 88 }; 89 90 static int ad5624r_get_powerdown_mode(struct iio_dev *indio_dev, 91 const struct iio_chan_spec *chan) 92 { 93 struct ad5624r_state *st = iio_priv(indio_dev); 94 95 return st->pwr_down_mode; 96 } 97 98 static int ad5624r_set_powerdown_mode(struct iio_dev *indio_dev, 99 const struct iio_chan_spec *chan, unsigned int mode) 100 { 101 struct ad5624r_state *st = iio_priv(indio_dev); 102 103 st->pwr_down_mode = mode; 104 105 return 0; 106 } 107 108 static const struct iio_enum ad5624r_powerdown_mode_enum = { 109 .items = ad5624r_powerdown_modes, 110 .num_items = ARRAY_SIZE(ad5624r_powerdown_modes), 111 .get = ad5624r_get_powerdown_mode, 112 .set = ad5624r_set_powerdown_mode, 113 }; 114 115 static ssize_t ad5624r_read_dac_powerdown(struct iio_dev *indio_dev, 116 uintptr_t private, const struct iio_chan_spec *chan, char *buf) 117 { 118 struct ad5624r_state *st = iio_priv(indio_dev); 119 120 return sysfs_emit(buf, "%d\n", 121 !!(st->pwr_down_mask & (1 << chan->channel))); 122 } 123 124 static ssize_t ad5624r_write_dac_powerdown(struct iio_dev *indio_dev, 125 uintptr_t private, const struct iio_chan_spec *chan, const char *buf, 126 size_t len) 127 { 128 bool pwr_down; 129 int ret; 130 struct ad5624r_state *st = iio_priv(indio_dev); 131 132 ret = kstrtobool(buf, &pwr_down); 133 if (ret) 134 return ret; 135 136 if (pwr_down) 137 st->pwr_down_mask |= (1 << chan->channel); 138 else 139 st->pwr_down_mask &= ~(1 << chan->channel); 140 141 ret = ad5624r_spi_write(st->us, AD5624R_CMD_POWERDOWN_DAC, 0, 142 (st->pwr_down_mode << 4) | 143 st->pwr_down_mask, 16); 144 145 return ret ? ret : len; 146 } 147 148 static const struct iio_info ad5624r_info = { 149 .write_raw = ad5624r_write_raw, 150 .read_raw = ad5624r_read_raw, 151 }; 152 153 static const struct iio_chan_spec_ext_info ad5624r_ext_info[] = { 154 { 155 .name = "powerdown", 156 .read = ad5624r_read_dac_powerdown, 157 .write = ad5624r_write_dac_powerdown, 158 .shared = IIO_SEPARATE, 159 }, 160 IIO_ENUM("powerdown_mode", IIO_SHARED_BY_TYPE, 161 &ad5624r_powerdown_mode_enum), 162 IIO_ENUM_AVAILABLE("powerdown_mode", IIO_SHARED_BY_TYPE, &ad5624r_powerdown_mode_enum), 163 { }, 164 }; 165 166 #define AD5624R_CHANNEL(_chan, _bits) { \ 167 .type = IIO_VOLTAGE, \ 168 .indexed = 1, \ 169 .output = 1, \ 170 .channel = (_chan), \ 171 .info_mask_separate = BIT(IIO_CHAN_INFO_RAW), \ 172 .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE), \ 173 .address = (_chan), \ 174 .scan_type = { \ 175 .sign = 'u', \ 176 .realbits = (_bits), \ 177 .storagebits = 16, \ 178 .shift = 16 - (_bits), \ 179 }, \ 180 .ext_info = ad5624r_ext_info, \ 181 } 182 183 #define DECLARE_AD5624R_CHANNELS(_name, _bits) \ 184 const struct iio_chan_spec _name##_channels[] = { \ 185 AD5624R_CHANNEL(0, _bits), \ 186 AD5624R_CHANNEL(1, _bits), \ 187 AD5624R_CHANNEL(2, _bits), \ 188 AD5624R_CHANNEL(3, _bits), \ 189 } 190 191 static DECLARE_AD5624R_CHANNELS(ad5624r, 12); 192 static DECLARE_AD5624R_CHANNELS(ad5644r, 14); 193 static DECLARE_AD5624R_CHANNELS(ad5664r, 16); 194 195 static const struct ad5624r_chip_info ad5624r_chip_info_tbl[] = { 196 [ID_AD5624R3] = { 197 .channels = ad5624r_channels, 198 .int_vref_mv = 1250, 199 }, 200 [ID_AD5624R5] = { 201 .channels = ad5624r_channels, 202 .int_vref_mv = 2500, 203 }, 204 [ID_AD5644R3] = { 205 .channels = ad5644r_channels, 206 .int_vref_mv = 1250, 207 }, 208 [ID_AD5644R5] = { 209 .channels = ad5644r_channels, 210 .int_vref_mv = 2500, 211 }, 212 [ID_AD5664R3] = { 213 .channels = ad5664r_channels, 214 .int_vref_mv = 1250, 215 }, 216 [ID_AD5664R5] = { 217 .channels = ad5664r_channels, 218 .int_vref_mv = 2500, 219 }, 220 }; 221 222 static int ad5624r_probe(struct spi_device *spi) 223 { 224 struct ad5624r_state *st; 225 struct iio_dev *indio_dev; 226 int ret, voltage_uv = 0; 227 228 indio_dev = devm_iio_device_alloc(&spi->dev, sizeof(*st)); 229 if (!indio_dev) 230 return -ENOMEM; 231 st = iio_priv(indio_dev); 232 st->reg = devm_regulator_get_optional(&spi->dev, "vref"); 233 if (!IS_ERR(st->reg)) { 234 ret = regulator_enable(st->reg); 235 if (ret) 236 return ret; 237 238 ret = regulator_get_voltage(st->reg); 239 if (ret < 0) 240 goto error_disable_reg; 241 242 voltage_uv = ret; 243 } else { 244 if (PTR_ERR(st->reg) != -ENODEV) 245 return PTR_ERR(st->reg); 246 /* Backwards compatibility. This naming is not correct */ 247 st->reg = devm_regulator_get_optional(&spi->dev, "vcc"); 248 if (!IS_ERR(st->reg)) { 249 ret = regulator_enable(st->reg); 250 if (ret) 251 return ret; 252 253 ret = regulator_get_voltage(st->reg); 254 if (ret < 0) 255 goto error_disable_reg; 256 257 voltage_uv = ret; 258 } 259 } 260 261 spi_set_drvdata(spi, indio_dev); 262 st->chip_info = 263 &ad5624r_chip_info_tbl[spi_get_device_id(spi)->driver_data]; 264 265 if (voltage_uv) 266 st->vref_mv = voltage_uv / 1000; 267 else 268 st->vref_mv = st->chip_info->int_vref_mv; 269 270 st->us = spi; 271 272 indio_dev->name = spi_get_device_id(spi)->name; 273 indio_dev->info = &ad5624r_info; 274 indio_dev->modes = INDIO_DIRECT_MODE; 275 indio_dev->channels = st->chip_info->channels; 276 indio_dev->num_channels = AD5624R_DAC_CHANNELS; 277 278 ret = ad5624r_spi_write(spi, AD5624R_CMD_INTERNAL_REFER_SETUP, 0, 279 !!voltage_uv, 16); 280 if (ret) 281 goto error_disable_reg; 282 283 ret = iio_device_register(indio_dev); 284 if (ret) 285 goto error_disable_reg; 286 287 return 0; 288 289 error_disable_reg: 290 if (!IS_ERR(st->reg)) 291 regulator_disable(st->reg); 292 293 return ret; 294 } 295 296 static void ad5624r_remove(struct spi_device *spi) 297 { 298 struct iio_dev *indio_dev = spi_get_drvdata(spi); 299 struct ad5624r_state *st = iio_priv(indio_dev); 300 301 iio_device_unregister(indio_dev); 302 if (!IS_ERR(st->reg)) 303 regulator_disable(st->reg); 304 } 305 306 static const struct spi_device_id ad5624r_id[] = { 307 {"ad5624r3", ID_AD5624R3}, 308 {"ad5644r3", ID_AD5644R3}, 309 {"ad5664r3", ID_AD5664R3}, 310 {"ad5624r5", ID_AD5624R5}, 311 {"ad5644r5", ID_AD5644R5}, 312 {"ad5664r5", ID_AD5664R5}, 313 {} 314 }; 315 MODULE_DEVICE_TABLE(spi, ad5624r_id); 316 317 static struct spi_driver ad5624r_driver = { 318 .driver = { 319 .name = "ad5624r", 320 }, 321 .probe = ad5624r_probe, 322 .remove = ad5624r_remove, 323 .id_table = ad5624r_id, 324 }; 325 module_spi_driver(ad5624r_driver); 326 327 MODULE_AUTHOR("Barry Song <21cnbao@gmail.com>"); 328 MODULE_DESCRIPTION("Analog Devices AD5624/44/64R DAC spi driver"); 329 MODULE_LICENSE("GPL v2"); 330