drivers/iio/adc/ad7091r8.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 /*
   3  * Analog Devices AD7091R8 12-bit SAR ADC driver
   4  *
   5  * Copyright 2023 Analog Devices Inc.
   6  */
   7
   8 #include <linux/bitfield.h>
   9 #include <linux/iio/iio.h>
  10 #include <linux/module.h>
  11 #include <linux/regmap.h>
  12 #include <linux/gpio/consumer.h>
  13 #include <linux/spi/spi.h>
  14
  15 #include "ad7091r-base.h"
  16
  17 #define AD7091R8_REG_ADDR_MSK                           GENMASK(15, 11)
  18 #define AD7091R8_RD_WR_FLAG_MSK                         BIT(10)
  19 #define AD7091R8_REG_DATA_MSK                           GENMASK(9, 0)
  20
  21 #define AD7091R_SPI_REGMAP_CONFIG(n) {                                  \
  22         .reg_bits = 8,                                                  \
  23         .val_bits = 16,                                                 \
  24         .volatile_reg = ad7091r_volatile_reg,                           \
  25         .writeable_reg = ad7091r_writeable_reg,                         \
  26         .max_register = AD7091R_REG_CH_HYSTERESIS(n),                   \
  27 }
  28
  29 static int ad7091r8_set_mode(struct ad7091r_state *st, enum ad7091r_mode mode)
  30 {
  31         /* AD7091R-2/-4/-8 don't set sample/command/autocycle mode in conf reg */
  32         st->mode = mode;
  33         return 0;
  34 }
  35
  36 static unsigned int ad7091r8_reg_result_chan_id(unsigned int val)
  37 {
  38         return AD7091R8_REG_RESULT_CH_ID(val);
  39 }
  40
  41 #define AD7091R_SPI_CHIP_INFO(_n, _name) {                              \
  42         .name = _name,                                                  \
  43         .channels = ad7091r##_n##_channels,                             \
  44         .num_channels = ARRAY_SIZE(ad7091r##_n##_channels),             \
  45         .vref_mV = 2500,                                                \
  46         .reg_result_chan_id = &ad7091r8_reg_result_chan_id,     \
  47         .set_mode = &ad7091r8_set_mode,                         \
  48 }
  49
  50 #define AD7091R_SPI_CHIP_INFO_IRQ(_n, _name) {                          \
  51         .name = _name,                                                  \
  52         .channels = ad7091r##_n##_channels_irq,                         \
  53         .num_channels = ARRAY_SIZE(ad7091r##_n##_channels_irq),         \
  54         .vref_mV = 2500,                                                \
  55         .reg_result_chan_id = &ad7091r8_reg_result_chan_id,     \
  56         .set_mode = &ad7091r8_set_mode,                         \
  57 }
  58
  59 enum ad7091r8_info_ids {
  60         AD7091R2_INFO,
  61         AD7091R4_INFO,
  62         AD7091R4_INFO_IRQ,
  63         AD7091R8_INFO,
  64         AD7091R8_INFO_IRQ,
  65 };
  66
  67 static const struct iio_chan_spec ad7091r2_channels[] = {
  68         AD7091R_CHANNEL(0, 12, NULL, 0),
  69         AD7091R_CHANNEL(1, 12, NULL, 0),
  70 };
  71
  72 static const struct iio_chan_spec ad7091r4_channels[] = {
  73         AD7091R_CHANNEL(0, 12, NULL, 0),
  74         AD7091R_CHANNEL(1, 12, NULL, 0),
  75         AD7091R_CHANNEL(2, 12, NULL, 0),
  76         AD7091R_CHANNEL(3, 12, NULL, 0),
  77 };
  78
  79 static const struct iio_chan_spec ad7091r4_channels_irq[] = {
  80         AD7091R_CHANNEL(0, 12, ad7091r_events, ARRAY_SIZE(ad7091r_events)),
  81         AD7091R_CHANNEL(1, 12, ad7091r_events, ARRAY_SIZE(ad7091r_events)),
  82         AD7091R_CHANNEL(2, 12, ad7091r_events, ARRAY_SIZE(ad7091r_events)),
  83         AD7091R_CHANNEL(3, 12, ad7091r_events, ARRAY_SIZE(ad7091r_events)),
  84 };
  85
  86 static const struct iio_chan_spec ad7091r8_channels[] = {
  87         AD7091R_CHANNEL(0, 12, NULL, 0),
  88         AD7091R_CHANNEL(1, 12, NULL, 0),
  89         AD7091R_CHANNEL(2, 12, NULL, 0),
  90         AD7091R_CHANNEL(3, 12, NULL, 0),
  91         AD7091R_CHANNEL(4, 12, NULL, 0),
  92         AD7091R_CHANNEL(5, 12, NULL, 0),
  93         AD7091R_CHANNEL(6, 12, NULL, 0),
  94         AD7091R_CHANNEL(7, 12, NULL, 0),
  95 };
  96
  97 static const struct iio_chan_spec ad7091r8_channels_irq[] = {
  98         AD7091R_CHANNEL(0, 12, ad7091r_events, ARRAY_SIZE(ad7091r_events)),
  99         AD7091R_CHANNEL(1, 12, ad7091r_events, ARRAY_SIZE(ad7091r_events)),
 100         AD7091R_CHANNEL(2, 12, ad7091r_events, ARRAY_SIZE(ad7091r_events)),
 101         AD7091R_CHANNEL(3, 12, ad7091r_events, ARRAY_SIZE(ad7091r_events)),
 102         AD7091R_CHANNEL(4, 12, ad7091r_events, ARRAY_SIZE(ad7091r_events)),
 103         AD7091R_CHANNEL(5, 12, ad7091r_events, ARRAY_SIZE(ad7091r_events)),
 104         AD7091R_CHANNEL(6, 12, ad7091r_events, ARRAY_SIZE(ad7091r_events)),
 105         AD7091R_CHANNEL(7, 12, ad7091r_events, ARRAY_SIZE(ad7091r_events)),
 106 };
 107
 108 static void ad7091r_pulse_convst(struct ad7091r_state *st)
 109 {
 110         gpiod_set_value_cansleep(st->convst_gpio, 1);
 111         gpiod_set_value_cansleep(st->convst_gpio, 0);
 112 }
 113
 114 static int ad7091r_regmap_bus_reg_read(void *context, unsigned int reg,
 115                                        unsigned int *val)
 116 {
 117         struct ad7091r_state *st = context;
 118         struct spi_device *spi = container_of(st->dev, struct spi_device, dev);
 119         int ret;
 120
 121         struct spi_transfer t[] = {
 122                 {
 123                         .tx_buf = &st->tx_buf,
 124                         .len = 2,
 125                         .cs_change = 1,
 126                 }, {
 127                         .rx_buf = &st->rx_buf,
 128                         .len = 2,
 129                 }
 130         };
 131
 132         if (reg == AD7091R_REG_RESULT)
 133                 ad7091r_pulse_convst(st);
 134
 135         st->tx_buf = cpu_to_be16(reg << 11);
 136
 137         ret = spi_sync_transfer(spi, t, ARRAY_SIZE(t));
 138         if (ret < 0)
 139                 return ret;
 140
 141         *val = be16_to_cpu(st->rx_buf);
 142         return 0;
 143 }
 144
 145 static int ad7091r_regmap_bus_reg_write(void *context, unsigned int reg,
 146                                         unsigned int val)
 147 {
 148         struct ad7091r_state *st = context;
 149         struct spi_device *spi = container_of(st->dev, struct spi_device, dev);
 150
 151         /*
 152          * AD7091R-2/-4/-8 protocol (datasheet page 31) is to do a single SPI
 153          * transfer with reg address set in bits B15:B11 and value set in B9:B0.
 154          */
 155         st->tx_buf = cpu_to_be16(FIELD_PREP(AD7091R8_REG_DATA_MSK, val) |
 156                                  FIELD_PREP(AD7091R8_RD_WR_FLAG_MSK, 1) |
 157                                  FIELD_PREP(AD7091R8_REG_ADDR_MSK, reg));
 158
 159         return spi_write(spi, &st->tx_buf, 2);
 160 }
 161
 162 static struct regmap_bus ad7091r8_regmap_bus = {
 163         .reg_read = ad7091r_regmap_bus_reg_read,
 164         .reg_write = ad7091r_regmap_bus_reg_write,
 165         .reg_format_endian_default = REGMAP_ENDIAN_BIG,
 166         .val_format_endian_default = REGMAP_ENDIAN_BIG,
 167 };
 168
 169 static const struct ad7091r_chip_info ad7091r8_infos[] = {
 170         [AD7091R2_INFO] = AD7091R_SPI_CHIP_INFO(2, "ad7091r-2"),
 171         [AD7091R4_INFO] = AD7091R_SPI_CHIP_INFO(4, "ad7091r-4"),
 172         [AD7091R4_INFO_IRQ] = AD7091R_SPI_CHIP_INFO_IRQ(4, "ad7091r-4"),
 173         [AD7091R8_INFO] = AD7091R_SPI_CHIP_INFO(8, "ad7091r-8"),
 174         [AD7091R8_INFO_IRQ] = AD7091R_SPI_CHIP_INFO_IRQ(8, "ad7091r-8")
 175 };
 176
 177 static const struct regmap_config ad7091r2_reg_conf = AD7091R_SPI_REGMAP_CONFIG(2);
 178 static const struct regmap_config ad7091r4_reg_conf = AD7091R_SPI_REGMAP_CONFIG(4);
 179 static const struct regmap_config ad7091r8_reg_conf = AD7091R_SPI_REGMAP_CONFIG(8);
 180
 181 static void ad7091r8_regmap_init(struct ad7091r_state *st,
 182                                  const struct regmap_config *regmap_conf)
 183 {
 184         st->map = devm_regmap_init(st->dev, &ad7091r8_regmap_bus, st,
 185                                    regmap_conf);
 186 }
 187
 188 static int ad7091r8_gpio_setup(struct ad7091r_state *st)
 189 {
 190         st->convst_gpio = devm_gpiod_get(st->dev, "convst", GPIOD_OUT_LOW);
 191         if (IS_ERR(st->convst_gpio))
 192                 return dev_err_probe(st->dev, PTR_ERR(st->convst_gpio),
 193                                      "Error getting convst GPIO\n");
 194
 195         st->reset_gpio = devm_gpiod_get_optional(st->dev, "reset",
 196                                                  GPIOD_OUT_HIGH);
 197         if (IS_ERR(st->reset_gpio))
 198                 return dev_err_probe(st->dev, PTR_ERR(st->reset_gpio),
 199                                      "Error on requesting reset GPIO\n");
 200
 201         if (st->reset_gpio) {
 202                 fsleep(20);
 203                 gpiod_set_value_cansleep(st->reset_gpio, 0);
 204         }
 205
 206         return 0;
 207 }
 208
 209 static struct ad7091r_init_info ad7091r2_init_info = {
 210         .info_no_irq = &ad7091r8_infos[AD7091R2_INFO],
 211         .regmap_config = &ad7091r2_reg_conf,
 212         .init_adc_regmap = &ad7091r8_regmap_init,
 213         .setup = &ad7091r8_gpio_setup
 214 };
 215
 216 static struct ad7091r_init_info ad7091r4_init_info = {
 217         .info_no_irq = &ad7091r8_infos[AD7091R4_INFO],
 218         .info_irq = &ad7091r8_infos[AD7091R4_INFO_IRQ],
 219         .regmap_config = &ad7091r4_reg_conf,
 220         .init_adc_regmap = &ad7091r8_regmap_init,
 221         .setup = &ad7091r8_gpio_setup
 222 };
 223
 224 static struct ad7091r_init_info ad7091r8_init_info = {
 225         .info_no_irq = &ad7091r8_infos[AD7091R8_INFO],
 226         .info_irq = &ad7091r8_infos[AD7091R8_INFO_IRQ],
 227         .regmap_config = &ad7091r8_reg_conf,
 228         .init_adc_regmap = &ad7091r8_regmap_init,
 229         .setup = &ad7091r8_gpio_setup
 230 };
 231
 232 static int ad7091r8_spi_probe(struct spi_device *spi)
 233 {
 234         const struct ad7091r_init_info *init_info;
 235
 236         init_info = spi_get_device_match_data(spi);
 237         if (!init_info)
 238                 return -EINVAL;
 239
 240         return ad7091r_probe(&spi->dev, init_info, spi->irq);
 241 }
 242
 243 static const struct of_device_id ad7091r8_of_match[] = {
 244         { .compatible = "adi,ad7091r2", .data = &ad7091r2_init_info },
 245         { .compatible = "adi,ad7091r4", .data = &ad7091r4_init_info },
 246         { .compatible = "adi,ad7091r8", .data = &ad7091r8_init_info },
 247         { }
 248 };
 249 MODULE_DEVICE_TABLE(of, ad7091r8_of_match);
 250
 251 static const struct spi_device_id ad7091r8_spi_id[] = {
 252         { "ad7091r2", (kernel_ulong_t)&ad7091r2_init_info },
 253         { "ad7091r4", (kernel_ulong_t)&ad7091r4_init_info },
 254         { "ad7091r8", (kernel_ulong_t)&ad7091r8_init_info },
 255         { }
 256 };
 257 MODULE_DEVICE_TABLE(spi, ad7091r8_spi_id);
 258
 259 static struct spi_driver ad7091r8_driver = {
 260         .driver = {
 261                 .name = "ad7091r8",
 262                 .of_match_table = ad7091r8_of_match,
 263         },
 264         .probe = ad7091r8_spi_probe,
 265         .id_table = ad7091r8_spi_id,
 266 };
 267 module_spi_driver(ad7091r8_driver);
 268
 269 MODULE_AUTHOR("Marcelo Schmitt <marcelo.schmitt@analog.com>");
 270 MODULE_DESCRIPTION("Analog Devices AD7091R8 ADC driver");
 271 MODULE_LICENSE("GPL");
 272 MODULE_IMPORT_NS(IIO_AD7091R);