Thomas Gleixner | d2912cb | 2019-06-04 10:11:33 +0200 | [diff] [blame^] | 1 | // SPDX-License-Identifier: GPL-2.0-only |
Oskar Andero | f5ce4a7 | 2013-05-03 10:58:00 +0100 | [diff] [blame] | 2 | /* |
| 3 | * Copyright (C) 2013 Oskar Andero <oskar.andero@gmail.com> |
Søren Andersen | b12206e | 2014-10-08 20:42:00 +0200 | [diff] [blame] | 4 | * Copyright (C) 2014 Rose Technology |
| 5 | * Allan Bendorff Jensen <abj@rosetechnology.dk> |
| 6 | * Soren Andersen <san@rosetechnology.dk> |
Oskar Andero | f5ce4a7 | 2013-05-03 10:58:00 +0100 | [diff] [blame] | 7 | * |
Søren Andersen | b12206e | 2014-10-08 20:42:00 +0200 | [diff] [blame] | 8 | * Driver for following ADC chips from Microchip Technology's: |
| 9 | * 10 Bit converter |
| 10 | * MCP3001 |
| 11 | * MCP3002 |
| 12 | * MCP3004 |
| 13 | * MCP3008 |
| 14 | * ------------ |
| 15 | * 12 bit converter |
| 16 | * MCP3201 |
| 17 | * MCP3202 |
| 18 | * MCP3204 |
| 19 | * MCP3208 |
| 20 | * ------------ |
Lukas Wunner | e6f4794 | 2017-08-22 15:33:00 +0200 | [diff] [blame] | 21 | * 13 bit converter |
| 22 | * MCP3301 |
Lukas Wunner | c1375d6 | 2017-09-09 20:32:41 +0200 | [diff] [blame] | 23 | * ------------ |
| 24 | * 22 bit converter |
| 25 | * MCP3550 |
| 26 | * MCP3551 |
| 27 | * MCP3553 |
Søren Andersen | b12206e | 2014-10-08 20:42:00 +0200 | [diff] [blame] | 28 | * |
Oskar Andero | f5ce4a7 | 2013-05-03 10:58:00 +0100 | [diff] [blame] | 29 | * Datasheet can be found here: |
Søren Andersen | b12206e | 2014-10-08 20:42:00 +0200 | [diff] [blame] | 30 | * http://ww1.microchip.com/downloads/en/DeviceDoc/21293C.pdf mcp3001 |
| 31 | * http://ww1.microchip.com/downloads/en/DeviceDoc/21294E.pdf mcp3002 |
| 32 | * http://ww1.microchip.com/downloads/en/DeviceDoc/21295d.pdf mcp3004/08 |
| 33 | * http://ww1.microchip.com/downloads/en/DeviceDoc/21290D.pdf mcp3201 |
| 34 | * http://ww1.microchip.com/downloads/en/DeviceDoc/21034D.pdf mcp3202 |
| 35 | * http://ww1.microchip.com/downloads/en/DeviceDoc/21298c.pdf mcp3204/08 |
Andrea Galbusera | f686a36 | 2015-07-14 15:36:21 +0200 | [diff] [blame] | 36 | * http://ww1.microchip.com/downloads/en/DeviceDoc/21700E.pdf mcp3301 |
Lukas Wunner | c1375d6 | 2017-09-09 20:32:41 +0200 | [diff] [blame] | 37 | * http://ww1.microchip.com/downloads/en/DeviceDoc/21950D.pdf mcp3550/1/3 |
Oskar Andero | f5ce4a7 | 2013-05-03 10:58:00 +0100 | [diff] [blame] | 38 | */ |
| 39 | |
| 40 | #include <linux/err.h> |
Søren Andersen | b12206e | 2014-10-08 20:42:00 +0200 | [diff] [blame] | 41 | #include <linux/delay.h> |
Oskar Andero | f5ce4a7 | 2013-05-03 10:58:00 +0100 | [diff] [blame] | 42 | #include <linux/spi/spi.h> |
| 43 | #include <linux/module.h> |
| 44 | #include <linux/iio/iio.h> |
| 45 | #include <linux/regulator/consumer.h> |
| 46 | |
Oskar Andero | f5ce4a7 | 2013-05-03 10:58:00 +0100 | [diff] [blame] | 47 | enum { |
Søren Andersen | b12206e | 2014-10-08 20:42:00 +0200 | [diff] [blame] | 48 | mcp3001, |
| 49 | mcp3002, |
| 50 | mcp3004, |
| 51 | mcp3008, |
| 52 | mcp3201, |
| 53 | mcp3202, |
Oskar Andero | f5ce4a7 | 2013-05-03 10:58:00 +0100 | [diff] [blame] | 54 | mcp3204, |
| 55 | mcp3208, |
Andrea Galbusera | f686a36 | 2015-07-14 15:36:21 +0200 | [diff] [blame] | 56 | mcp3301, |
Lukas Wunner | c1375d6 | 2017-09-09 20:32:41 +0200 | [diff] [blame] | 57 | mcp3550_50, |
| 58 | mcp3550_60, |
| 59 | mcp3551, |
| 60 | mcp3553, |
Oskar Andero | f5ce4a7 | 2013-05-03 10:58:00 +0100 | [diff] [blame] | 61 | }; |
| 62 | |
Søren Andersen | b12206e | 2014-10-08 20:42:00 +0200 | [diff] [blame] | 63 | struct mcp320x_chip_info { |
| 64 | const struct iio_chan_spec *channels; |
| 65 | unsigned int num_channels; |
| 66 | unsigned int resolution; |
Lukas Wunner | c1375d6 | 2017-09-09 20:32:41 +0200 | [diff] [blame] | 67 | unsigned int conv_time; /* usec */ |
Søren Andersen | b12206e | 2014-10-08 20:42:00 +0200 | [diff] [blame] | 68 | }; |
| 69 | |
Lukas Wunner | 9c84c91 | 2017-09-09 20:32:41 +0200 | [diff] [blame] | 70 | /** |
| 71 | * struct mcp320x - Microchip SPI ADC instance |
| 72 | * @spi: SPI slave (parent of the IIO device) |
| 73 | * @msg: SPI message to select a channel and receive a value from the ADC |
| 74 | * @transfer: SPI transfers used by @msg |
Lukas Wunner | c1375d6 | 2017-09-09 20:32:41 +0200 | [diff] [blame] | 75 | * @start_conv_msg: SPI message to start a conversion by briefly asserting CS |
| 76 | * @start_conv_transfer: SPI transfer used by @start_conv_msg |
Lukas Wunner | 9c84c91 | 2017-09-09 20:32:41 +0200 | [diff] [blame] | 77 | * @reg: regulator generating Vref |
| 78 | * @lock: protects read sequences |
| 79 | * @chip_info: ADC properties |
| 80 | * @tx_buf: buffer for @transfer[0] (not used on single-channel converters) |
| 81 | * @rx_buf: buffer for @transfer[1] |
| 82 | */ |
Oskar Andero | f5ce4a7 | 2013-05-03 10:58:00 +0100 | [diff] [blame] | 83 | struct mcp320x { |
| 84 | struct spi_device *spi; |
| 85 | struct spi_message msg; |
| 86 | struct spi_transfer transfer[2]; |
Lukas Wunner | c1375d6 | 2017-09-09 20:32:41 +0200 | [diff] [blame] | 87 | struct spi_message start_conv_msg; |
| 88 | struct spi_transfer start_conv_transfer; |
Oskar Andero | f5ce4a7 | 2013-05-03 10:58:00 +0100 | [diff] [blame] | 89 | |
Oskar Andero | f5ce4a7 | 2013-05-03 10:58:00 +0100 | [diff] [blame] | 90 | struct regulator *reg; |
| 91 | struct mutex lock; |
Søren Andersen | b12206e | 2014-10-08 20:42:00 +0200 | [diff] [blame] | 92 | const struct mcp320x_chip_info *chip_info; |
Michael Welling | 0e81bc9 | 2015-05-06 11:49:17 -0500 | [diff] [blame] | 93 | |
| 94 | u8 tx_buf ____cacheline_aligned; |
Lukas Wunner | c1375d6 | 2017-09-09 20:32:41 +0200 | [diff] [blame] | 95 | u8 rx_buf[4]; |
Oskar Andero | f5ce4a7 | 2013-05-03 10:58:00 +0100 | [diff] [blame] | 96 | }; |
| 97 | |
Søren Andersen | b12206e | 2014-10-08 20:42:00 +0200 | [diff] [blame] | 98 | static int mcp320x_channel_to_tx_data(int device_index, |
| 99 | const unsigned int channel, bool differential) |
| 100 | { |
| 101 | int start_bit = 1; |
| 102 | |
| 103 | switch (device_index) { |
Søren Andersen | b12206e | 2014-10-08 20:42:00 +0200 | [diff] [blame] | 104 | case mcp3002: |
| 105 | case mcp3202: |
| 106 | return ((start_bit << 4) | (!differential << 3) | |
| 107 | (channel << 2)); |
| 108 | case mcp3004: |
| 109 | case mcp3204: |
| 110 | case mcp3008: |
| 111 | case mcp3208: |
| 112 | return ((start_bit << 6) | (!differential << 5) | |
| 113 | (channel << 2)); |
| 114 | default: |
| 115 | return -EINVAL; |
| 116 | } |
| 117 | } |
| 118 | |
| 119 | static int mcp320x_adc_conversion(struct mcp320x *adc, u8 channel, |
Lukas Wunner | e6f4794 | 2017-08-22 15:33:00 +0200 | [diff] [blame] | 120 | bool differential, int device_index, int *val) |
Oskar Andero | f5ce4a7 | 2013-05-03 10:58:00 +0100 | [diff] [blame] | 121 | { |
| 122 | int ret; |
| 123 | |
Lukas Wunner | c1375d6 | 2017-09-09 20:32:41 +0200 | [diff] [blame] | 124 | if (adc->chip_info->conv_time) { |
| 125 | ret = spi_sync(adc->spi, &adc->start_conv_msg); |
| 126 | if (ret < 0) |
| 127 | return ret; |
| 128 | |
| 129 | usleep_range(adc->chip_info->conv_time, |
| 130 | adc->chip_info->conv_time + 100); |
| 131 | } |
| 132 | |
Lukas Wunner | ea91031 | 2017-09-09 20:32:41 +0200 | [diff] [blame] | 133 | memset(&adc->rx_buf, 0, sizeof(adc->rx_buf)); |
| 134 | if (adc->chip_info->num_channels > 1) |
| 135 | adc->tx_buf = mcp320x_channel_to_tx_data(device_index, channel, |
| 136 | differential); |
Oskar Andero | f5ce4a7 | 2013-05-03 10:58:00 +0100 | [diff] [blame] | 137 | |
Lukas Wunner | ea91031 | 2017-09-09 20:32:41 +0200 | [diff] [blame] | 138 | ret = spi_sync(adc->spi, &adc->msg); |
| 139 | if (ret < 0) |
| 140 | return ret; |
Søren Andersen | b12206e | 2014-10-08 20:42:00 +0200 | [diff] [blame] | 141 | |
| 142 | switch (device_index) { |
| 143 | case mcp3001: |
Lukas Wunner | e6f4794 | 2017-08-22 15:33:00 +0200 | [diff] [blame] | 144 | *val = (adc->rx_buf[0] << 5 | adc->rx_buf[1] >> 3); |
| 145 | return 0; |
Søren Andersen | b12206e | 2014-10-08 20:42:00 +0200 | [diff] [blame] | 146 | case mcp3002: |
| 147 | case mcp3004: |
| 148 | case mcp3008: |
Lukas Wunner | e6f4794 | 2017-08-22 15:33:00 +0200 | [diff] [blame] | 149 | *val = (adc->rx_buf[0] << 2 | adc->rx_buf[1] >> 6); |
| 150 | return 0; |
Søren Andersen | b12206e | 2014-10-08 20:42:00 +0200 | [diff] [blame] | 151 | case mcp3201: |
Lukas Wunner | e6f4794 | 2017-08-22 15:33:00 +0200 | [diff] [blame] | 152 | *val = (adc->rx_buf[0] << 7 | adc->rx_buf[1] >> 1); |
| 153 | return 0; |
Søren Andersen | b12206e | 2014-10-08 20:42:00 +0200 | [diff] [blame] | 154 | case mcp3202: |
| 155 | case mcp3204: |
| 156 | case mcp3208: |
Lukas Wunner | e6f4794 | 2017-08-22 15:33:00 +0200 | [diff] [blame] | 157 | *val = (adc->rx_buf[0] << 4 | adc->rx_buf[1] >> 4); |
| 158 | return 0; |
Andrea Galbusera | f686a36 | 2015-07-14 15:36:21 +0200 | [diff] [blame] | 159 | case mcp3301: |
Lukas Wunner | e6f4794 | 2017-08-22 15:33:00 +0200 | [diff] [blame] | 160 | *val = sign_extend32((adc->rx_buf[0] & 0x1f) << 8 |
| 161 | | adc->rx_buf[1], 12); |
| 162 | return 0; |
Lukas Wunner | c1375d6 | 2017-09-09 20:32:41 +0200 | [diff] [blame] | 163 | case mcp3550_50: |
| 164 | case mcp3550_60: |
| 165 | case mcp3551: |
| 166 | case mcp3553: { |
| 167 | u32 raw = be32_to_cpup((u32 *)adc->rx_buf); |
| 168 | |
| 169 | if (!(adc->spi->mode & SPI_CPOL)) |
| 170 | raw <<= 1; /* strip Data Ready bit in SPI mode 0,0 */ |
| 171 | |
| 172 | /* |
| 173 | * If the input is within -vref and vref, bit 21 is the sign. |
| 174 | * Up to 12% overrange or underrange are allowed, in which case |
| 175 | * bit 23 is the sign and bit 0 to 21 is the value. |
| 176 | */ |
| 177 | raw >>= 8; |
| 178 | if (raw & BIT(22) && raw & BIT(23)) |
| 179 | return -EIO; /* cannot have overrange AND underrange */ |
| 180 | else if (raw & BIT(22)) |
| 181 | raw &= ~BIT(22); /* overrange */ |
| 182 | else if (raw & BIT(23) || raw & BIT(21)) |
| 183 | raw |= GENMASK(31, 22); /* underrange or negative */ |
| 184 | |
| 185 | *val = (s32)raw; |
| 186 | return 0; |
| 187 | } |
Søren Andersen | b12206e | 2014-10-08 20:42:00 +0200 | [diff] [blame] | 188 | default: |
| 189 | return -EINVAL; |
| 190 | } |
Oskar Andero | f5ce4a7 | 2013-05-03 10:58:00 +0100 | [diff] [blame] | 191 | } |
| 192 | |
| 193 | static int mcp320x_read_raw(struct iio_dev *indio_dev, |
| 194 | struct iio_chan_spec const *channel, int *val, |
| 195 | int *val2, long mask) |
| 196 | { |
| 197 | struct mcp320x *adc = iio_priv(indio_dev); |
| 198 | int ret = -EINVAL; |
Søren Andersen | b12206e | 2014-10-08 20:42:00 +0200 | [diff] [blame] | 199 | int device_index = 0; |
Oskar Andero | f5ce4a7 | 2013-05-03 10:58:00 +0100 | [diff] [blame] | 200 | |
| 201 | mutex_lock(&adc->lock); |
| 202 | |
Søren Andersen | b12206e | 2014-10-08 20:42:00 +0200 | [diff] [blame] | 203 | device_index = spi_get_device_id(adc->spi)->driver_data; |
| 204 | |
Oskar Andero | f5ce4a7 | 2013-05-03 10:58:00 +0100 | [diff] [blame] | 205 | switch (mask) { |
| 206 | case IIO_CHAN_INFO_RAW: |
Søren Andersen | b12206e | 2014-10-08 20:42:00 +0200 | [diff] [blame] | 207 | ret = mcp320x_adc_conversion(adc, channel->address, |
Lukas Wunner | e6f4794 | 2017-08-22 15:33:00 +0200 | [diff] [blame] | 208 | channel->differential, device_index, val); |
Oskar Andero | f5ce4a7 | 2013-05-03 10:58:00 +0100 | [diff] [blame] | 209 | if (ret < 0) |
| 210 | goto out; |
| 211 | |
Oskar Andero | f5ce4a7 | 2013-05-03 10:58:00 +0100 | [diff] [blame] | 212 | ret = IIO_VAL_INT; |
| 213 | break; |
| 214 | |
| 215 | case IIO_CHAN_INFO_SCALE: |
Oskar Andero | f5ce4a7 | 2013-05-03 10:58:00 +0100 | [diff] [blame] | 216 | ret = regulator_get_voltage(adc->reg); |
| 217 | if (ret < 0) |
| 218 | goto out; |
| 219 | |
Søren Andersen | b12206e | 2014-10-08 20:42:00 +0200 | [diff] [blame] | 220 | /* convert regulator output voltage to mV */ |
Oskar Andero | f5ce4a7 | 2013-05-03 10:58:00 +0100 | [diff] [blame] | 221 | *val = ret / 1000; |
Søren Andersen | b12206e | 2014-10-08 20:42:00 +0200 | [diff] [blame] | 222 | *val2 = adc->chip_info->resolution; |
Oskar Andero | f5ce4a7 | 2013-05-03 10:58:00 +0100 | [diff] [blame] | 223 | ret = IIO_VAL_FRACTIONAL_LOG2; |
| 224 | break; |
Oskar Andero | f5ce4a7 | 2013-05-03 10:58:00 +0100 | [diff] [blame] | 225 | } |
| 226 | |
| 227 | out: |
| 228 | mutex_unlock(&adc->lock); |
| 229 | |
| 230 | return ret; |
| 231 | } |
| 232 | |
| 233 | #define MCP320X_VOLTAGE_CHANNEL(num) \ |
| 234 | { \ |
| 235 | .type = IIO_VOLTAGE, \ |
| 236 | .indexed = 1, \ |
| 237 | .channel = (num), \ |
| 238 | .address = (num), \ |
| 239 | .info_mask_separate = BIT(IIO_CHAN_INFO_RAW), \ |
| 240 | .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE) \ |
| 241 | } |
| 242 | |
Akinobu Mita | 4ea71e5 | 2016-01-08 00:40:30 +0900 | [diff] [blame] | 243 | #define MCP320X_VOLTAGE_CHANNEL_DIFF(chan1, chan2) \ |
Oskar Andero | f5ce4a7 | 2013-05-03 10:58:00 +0100 | [diff] [blame] | 244 | { \ |
| 245 | .type = IIO_VOLTAGE, \ |
| 246 | .indexed = 1, \ |
Akinobu Mita | 4ea71e5 | 2016-01-08 00:40:30 +0900 | [diff] [blame] | 247 | .channel = (chan1), \ |
| 248 | .channel2 = (chan2), \ |
| 249 | .address = (chan1), \ |
Oskar Andero | f5ce4a7 | 2013-05-03 10:58:00 +0100 | [diff] [blame] | 250 | .differential = 1, \ |
| 251 | .info_mask_separate = BIT(IIO_CHAN_INFO_RAW), \ |
| 252 | .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE) \ |
| 253 | } |
| 254 | |
Søren Andersen | b12206e | 2014-10-08 20:42:00 +0200 | [diff] [blame] | 255 | static const struct iio_chan_spec mcp3201_channels[] = { |
Akinobu Mita | 4ea71e5 | 2016-01-08 00:40:30 +0900 | [diff] [blame] | 256 | MCP320X_VOLTAGE_CHANNEL_DIFF(0, 1), |
Søren Andersen | b12206e | 2014-10-08 20:42:00 +0200 | [diff] [blame] | 257 | }; |
| 258 | |
| 259 | static const struct iio_chan_spec mcp3202_channels[] = { |
| 260 | MCP320X_VOLTAGE_CHANNEL(0), |
| 261 | MCP320X_VOLTAGE_CHANNEL(1), |
Akinobu Mita | 4ea71e5 | 2016-01-08 00:40:30 +0900 | [diff] [blame] | 262 | MCP320X_VOLTAGE_CHANNEL_DIFF(0, 1), |
| 263 | MCP320X_VOLTAGE_CHANNEL_DIFF(1, 0), |
Søren Andersen | b12206e | 2014-10-08 20:42:00 +0200 | [diff] [blame] | 264 | }; |
| 265 | |
Oskar Andero | f5ce4a7 | 2013-05-03 10:58:00 +0100 | [diff] [blame] | 266 | static const struct iio_chan_spec mcp3204_channels[] = { |
| 267 | MCP320X_VOLTAGE_CHANNEL(0), |
| 268 | MCP320X_VOLTAGE_CHANNEL(1), |
| 269 | MCP320X_VOLTAGE_CHANNEL(2), |
| 270 | MCP320X_VOLTAGE_CHANNEL(3), |
Akinobu Mita | 4ea71e5 | 2016-01-08 00:40:30 +0900 | [diff] [blame] | 271 | MCP320X_VOLTAGE_CHANNEL_DIFF(0, 1), |
| 272 | MCP320X_VOLTAGE_CHANNEL_DIFF(1, 0), |
| 273 | MCP320X_VOLTAGE_CHANNEL_DIFF(2, 3), |
| 274 | MCP320X_VOLTAGE_CHANNEL_DIFF(3, 2), |
Oskar Andero | f5ce4a7 | 2013-05-03 10:58:00 +0100 | [diff] [blame] | 275 | }; |
| 276 | |
| 277 | static const struct iio_chan_spec mcp3208_channels[] = { |
| 278 | MCP320X_VOLTAGE_CHANNEL(0), |
| 279 | MCP320X_VOLTAGE_CHANNEL(1), |
| 280 | MCP320X_VOLTAGE_CHANNEL(2), |
| 281 | MCP320X_VOLTAGE_CHANNEL(3), |
| 282 | MCP320X_VOLTAGE_CHANNEL(4), |
| 283 | MCP320X_VOLTAGE_CHANNEL(5), |
| 284 | MCP320X_VOLTAGE_CHANNEL(6), |
| 285 | MCP320X_VOLTAGE_CHANNEL(7), |
Akinobu Mita | 4ea71e5 | 2016-01-08 00:40:30 +0900 | [diff] [blame] | 286 | MCP320X_VOLTAGE_CHANNEL_DIFF(0, 1), |
| 287 | MCP320X_VOLTAGE_CHANNEL_DIFF(1, 0), |
| 288 | MCP320X_VOLTAGE_CHANNEL_DIFF(2, 3), |
| 289 | MCP320X_VOLTAGE_CHANNEL_DIFF(3, 2), |
| 290 | MCP320X_VOLTAGE_CHANNEL_DIFF(4, 5), |
| 291 | MCP320X_VOLTAGE_CHANNEL_DIFF(5, 4), |
| 292 | MCP320X_VOLTAGE_CHANNEL_DIFF(6, 7), |
| 293 | MCP320X_VOLTAGE_CHANNEL_DIFF(7, 6), |
Oskar Andero | f5ce4a7 | 2013-05-03 10:58:00 +0100 | [diff] [blame] | 294 | }; |
| 295 | |
| 296 | static const struct iio_info mcp320x_info = { |
| 297 | .read_raw = mcp320x_read_raw, |
Oskar Andero | f5ce4a7 | 2013-05-03 10:58:00 +0100 | [diff] [blame] | 298 | }; |
| 299 | |
Søren Andersen | b12206e | 2014-10-08 20:42:00 +0200 | [diff] [blame] | 300 | static const struct mcp320x_chip_info mcp320x_chip_infos[] = { |
| 301 | [mcp3001] = { |
| 302 | .channels = mcp3201_channels, |
| 303 | .num_channels = ARRAY_SIZE(mcp3201_channels), |
| 304 | .resolution = 10 |
| 305 | }, |
| 306 | [mcp3002] = { |
| 307 | .channels = mcp3202_channels, |
| 308 | .num_channels = ARRAY_SIZE(mcp3202_channels), |
| 309 | .resolution = 10 |
| 310 | }, |
| 311 | [mcp3004] = { |
| 312 | .channels = mcp3204_channels, |
| 313 | .num_channels = ARRAY_SIZE(mcp3204_channels), |
| 314 | .resolution = 10 |
| 315 | }, |
| 316 | [mcp3008] = { |
| 317 | .channels = mcp3208_channels, |
| 318 | .num_channels = ARRAY_SIZE(mcp3208_channels), |
| 319 | .resolution = 10 |
| 320 | }, |
| 321 | [mcp3201] = { |
| 322 | .channels = mcp3201_channels, |
| 323 | .num_channels = ARRAY_SIZE(mcp3201_channels), |
| 324 | .resolution = 12 |
| 325 | }, |
| 326 | [mcp3202] = { |
| 327 | .channels = mcp3202_channels, |
| 328 | .num_channels = ARRAY_SIZE(mcp3202_channels), |
| 329 | .resolution = 12 |
| 330 | }, |
Oskar Andero | f5ce4a7 | 2013-05-03 10:58:00 +0100 | [diff] [blame] | 331 | [mcp3204] = { |
| 332 | .channels = mcp3204_channels, |
Søren Andersen | b12206e | 2014-10-08 20:42:00 +0200 | [diff] [blame] | 333 | .num_channels = ARRAY_SIZE(mcp3204_channels), |
| 334 | .resolution = 12 |
Oskar Andero | f5ce4a7 | 2013-05-03 10:58:00 +0100 | [diff] [blame] | 335 | }, |
| 336 | [mcp3208] = { |
| 337 | .channels = mcp3208_channels, |
Søren Andersen | b12206e | 2014-10-08 20:42:00 +0200 | [diff] [blame] | 338 | .num_channels = ARRAY_SIZE(mcp3208_channels), |
| 339 | .resolution = 12 |
Oskar Andero | f5ce4a7 | 2013-05-03 10:58:00 +0100 | [diff] [blame] | 340 | }, |
Andrea Galbusera | f686a36 | 2015-07-14 15:36:21 +0200 | [diff] [blame] | 341 | [mcp3301] = { |
| 342 | .channels = mcp3201_channels, |
| 343 | .num_channels = ARRAY_SIZE(mcp3201_channels), |
| 344 | .resolution = 13 |
| 345 | }, |
Lukas Wunner | c1375d6 | 2017-09-09 20:32:41 +0200 | [diff] [blame] | 346 | [mcp3550_50] = { |
| 347 | .channels = mcp3201_channels, |
| 348 | .num_channels = ARRAY_SIZE(mcp3201_channels), |
| 349 | .resolution = 21, |
| 350 | /* 2% max deviation + 144 clock periods to exit shutdown */ |
| 351 | .conv_time = 80000 * 1.02 + 144000 / 102.4, |
| 352 | }, |
| 353 | [mcp3550_60] = { |
| 354 | .channels = mcp3201_channels, |
| 355 | .num_channels = ARRAY_SIZE(mcp3201_channels), |
| 356 | .resolution = 21, |
| 357 | .conv_time = 66670 * 1.02 + 144000 / 122.88, |
| 358 | }, |
| 359 | [mcp3551] = { |
| 360 | .channels = mcp3201_channels, |
| 361 | .num_channels = ARRAY_SIZE(mcp3201_channels), |
| 362 | .resolution = 21, |
| 363 | .conv_time = 73100 * 1.02 + 144000 / 112.64, |
| 364 | }, |
| 365 | [mcp3553] = { |
| 366 | .channels = mcp3201_channels, |
| 367 | .num_channels = ARRAY_SIZE(mcp3201_channels), |
| 368 | .resolution = 21, |
| 369 | .conv_time = 16670 * 1.02 + 144000 / 122.88, |
| 370 | }, |
Oskar Andero | f5ce4a7 | 2013-05-03 10:58:00 +0100 | [diff] [blame] | 371 | }; |
| 372 | |
| 373 | static int mcp320x_probe(struct spi_device *spi) |
| 374 | { |
| 375 | struct iio_dev *indio_dev; |
| 376 | struct mcp320x *adc; |
Søren Andersen | b12206e | 2014-10-08 20:42:00 +0200 | [diff] [blame] | 377 | const struct mcp320x_chip_info *chip_info; |
Lukas Wunner | c1375d6 | 2017-09-09 20:32:41 +0200 | [diff] [blame] | 378 | int ret, device_index; |
Oskar Andero | f5ce4a7 | 2013-05-03 10:58:00 +0100 | [diff] [blame] | 379 | |
Sachin Kamat | a726dea | 2013-07-23 09:58:00 +0100 | [diff] [blame] | 380 | indio_dev = devm_iio_device_alloc(&spi->dev, sizeof(*adc)); |
Oskar Andero | f5ce4a7 | 2013-05-03 10:58:00 +0100 | [diff] [blame] | 381 | if (!indio_dev) |
| 382 | return -ENOMEM; |
| 383 | |
| 384 | adc = iio_priv(indio_dev); |
| 385 | adc->spi = spi; |
| 386 | |
| 387 | indio_dev->dev.parent = &spi->dev; |
Matt Ranostay | b541eaf | 2016-07-02 17:26:33 -0700 | [diff] [blame] | 388 | indio_dev->dev.of_node = spi->dev.of_node; |
Oskar Andero | f5ce4a7 | 2013-05-03 10:58:00 +0100 | [diff] [blame] | 389 | indio_dev->name = spi_get_device_id(spi)->name; |
| 390 | indio_dev->modes = INDIO_DIRECT_MODE; |
| 391 | indio_dev->info = &mcp320x_info; |
Lukas Wunner | 0964e40 | 2017-08-22 15:33:00 +0200 | [diff] [blame] | 392 | spi_set_drvdata(spi, indio_dev); |
Oskar Andero | f5ce4a7 | 2013-05-03 10:58:00 +0100 | [diff] [blame] | 393 | |
Lukas Wunner | c1375d6 | 2017-09-09 20:32:41 +0200 | [diff] [blame] | 394 | device_index = spi_get_device_id(spi)->driver_data; |
| 395 | chip_info = &mcp320x_chip_infos[device_index]; |
Oskar Andero | f5ce4a7 | 2013-05-03 10:58:00 +0100 | [diff] [blame] | 396 | indio_dev->channels = chip_info->channels; |
| 397 | indio_dev->num_channels = chip_info->num_channels; |
| 398 | |
Manfred Schlaegl | 41be6a0 | 2015-07-10 22:55:30 +0200 | [diff] [blame] | 399 | adc->chip_info = chip_info; |
| 400 | |
Oskar Andero | f5ce4a7 | 2013-05-03 10:58:00 +0100 | [diff] [blame] | 401 | adc->transfer[0].tx_buf = &adc->tx_buf; |
| 402 | adc->transfer[0].len = sizeof(adc->tx_buf); |
| 403 | adc->transfer[1].rx_buf = adc->rx_buf; |
Lukas Wunner | c1375d6 | 2017-09-09 20:32:41 +0200 | [diff] [blame] | 404 | adc->transfer[1].len = DIV_ROUND_UP(chip_info->resolution, 8); |
| 405 | |
Lukas Wunner | ea91031 | 2017-09-09 20:32:41 +0200 | [diff] [blame] | 406 | if (chip_info->num_channels == 1) |
| 407 | /* single-channel converters are rx only (no MOSI pin) */ |
| 408 | spi_message_init_with_transfers(&adc->msg, |
| 409 | &adc->transfer[1], 1); |
| 410 | else |
| 411 | spi_message_init_with_transfers(&adc->msg, adc->transfer, |
| 412 | ARRAY_SIZE(adc->transfer)); |
Oskar Andero | f5ce4a7 | 2013-05-03 10:58:00 +0100 | [diff] [blame] | 413 | |
Lukas Wunner | c1375d6 | 2017-09-09 20:32:41 +0200 | [diff] [blame] | 414 | switch (device_index) { |
| 415 | case mcp3550_50: |
| 416 | case mcp3550_60: |
| 417 | case mcp3551: |
| 418 | case mcp3553: |
| 419 | /* rx len increases from 24 to 25 bit in SPI mode 0,0 */ |
| 420 | if (!(spi->mode & SPI_CPOL)) |
| 421 | adc->transfer[1].len++; |
| 422 | |
| 423 | /* conversions are started by asserting CS pin for 8 usec */ |
| 424 | adc->start_conv_transfer.delay_usecs = 8; |
| 425 | spi_message_init_with_transfers(&adc->start_conv_msg, |
| 426 | &adc->start_conv_transfer, 1); |
| 427 | |
| 428 | /* |
| 429 | * If CS was previously kept low (continuous conversion mode) |
| 430 | * and then changed to high, the chip is in shutdown. |
| 431 | * Sometimes it fails to wake from shutdown and clocks out |
| 432 | * only 0xffffff. The magic sequence of performing two |
| 433 | * conversions without delay between them resets the chip |
| 434 | * and ensures all subsequent conversions succeed. |
| 435 | */ |
| 436 | mcp320x_adc_conversion(adc, 0, 1, device_index, &ret); |
| 437 | mcp320x_adc_conversion(adc, 0, 1, device_index, &ret); |
| 438 | } |
| 439 | |
Sachin Kamat | a726dea | 2013-07-23 09:58:00 +0100 | [diff] [blame] | 440 | adc->reg = devm_regulator_get(&spi->dev, "vref"); |
| 441 | if (IS_ERR(adc->reg)) |
| 442 | return PTR_ERR(adc->reg); |
Oskar Andero | f5ce4a7 | 2013-05-03 10:58:00 +0100 | [diff] [blame] | 443 | |
| 444 | ret = regulator_enable(adc->reg); |
| 445 | if (ret < 0) |
Sachin Kamat | a726dea | 2013-07-23 09:58:00 +0100 | [diff] [blame] | 446 | return ret; |
Oskar Andero | f5ce4a7 | 2013-05-03 10:58:00 +0100 | [diff] [blame] | 447 | |
| 448 | mutex_init(&adc->lock); |
| 449 | |
| 450 | ret = iio_device_register(indio_dev); |
| 451 | if (ret < 0) |
| 452 | goto reg_disable; |
| 453 | |
| 454 | return 0; |
| 455 | |
| 456 | reg_disable: |
| 457 | regulator_disable(adc->reg); |
Oskar Andero | f5ce4a7 | 2013-05-03 10:58:00 +0100 | [diff] [blame] | 458 | |
| 459 | return ret; |
| 460 | } |
| 461 | |
| 462 | static int mcp320x_remove(struct spi_device *spi) |
| 463 | { |
| 464 | struct iio_dev *indio_dev = spi_get_drvdata(spi); |
| 465 | struct mcp320x *adc = iio_priv(indio_dev); |
| 466 | |
| 467 | iio_device_unregister(indio_dev); |
| 468 | regulator_disable(adc->reg); |
Oskar Andero | f5ce4a7 | 2013-05-03 10:58:00 +0100 | [diff] [blame] | 469 | |
| 470 | return 0; |
| 471 | } |
| 472 | |
Søren Andersen | b12206e | 2014-10-08 20:42:00 +0200 | [diff] [blame] | 473 | #if defined(CONFIG_OF) |
| 474 | static const struct of_device_id mcp320x_dt_ids[] = { |
Javier Martinez Canillas | 0d0e538 | 2015-10-14 14:54:39 +0200 | [diff] [blame] | 475 | /* NOTE: The use of compatibles with no vendor prefix is deprecated. */ |
Lukas Wunner | 35ed9fb | 2017-09-09 20:32:41 +0200 | [diff] [blame] | 476 | { .compatible = "mcp3001" }, |
| 477 | { .compatible = "mcp3002" }, |
| 478 | { .compatible = "mcp3004" }, |
| 479 | { .compatible = "mcp3008" }, |
| 480 | { .compatible = "mcp3201" }, |
| 481 | { .compatible = "mcp3202" }, |
| 482 | { .compatible = "mcp3204" }, |
| 483 | { .compatible = "mcp3208" }, |
| 484 | { .compatible = "mcp3301" }, |
| 485 | { .compatible = "microchip,mcp3001" }, |
| 486 | { .compatible = "microchip,mcp3002" }, |
| 487 | { .compatible = "microchip,mcp3004" }, |
| 488 | { .compatible = "microchip,mcp3008" }, |
| 489 | { .compatible = "microchip,mcp3201" }, |
| 490 | { .compatible = "microchip,mcp3202" }, |
| 491 | { .compatible = "microchip,mcp3204" }, |
| 492 | { .compatible = "microchip,mcp3208" }, |
| 493 | { .compatible = "microchip,mcp3301" }, |
Lukas Wunner | c1375d6 | 2017-09-09 20:32:41 +0200 | [diff] [blame] | 494 | { .compatible = "microchip,mcp3550-50" }, |
| 495 | { .compatible = "microchip,mcp3550-60" }, |
| 496 | { .compatible = "microchip,mcp3551" }, |
| 497 | { .compatible = "microchip,mcp3553" }, |
Lukas Wunner | 35ed9fb | 2017-09-09 20:32:41 +0200 | [diff] [blame] | 498 | { } |
Søren Andersen | b12206e | 2014-10-08 20:42:00 +0200 | [diff] [blame] | 499 | }; |
| 500 | MODULE_DEVICE_TABLE(of, mcp320x_dt_ids); |
| 501 | #endif |
| 502 | |
Oskar Andero | f5ce4a7 | 2013-05-03 10:58:00 +0100 | [diff] [blame] | 503 | static const struct spi_device_id mcp320x_id[] = { |
Søren Andersen | b12206e | 2014-10-08 20:42:00 +0200 | [diff] [blame] | 504 | { "mcp3001", mcp3001 }, |
| 505 | { "mcp3002", mcp3002 }, |
| 506 | { "mcp3004", mcp3004 }, |
| 507 | { "mcp3008", mcp3008 }, |
| 508 | { "mcp3201", mcp3201 }, |
| 509 | { "mcp3202", mcp3202 }, |
Oskar Andero | f5ce4a7 | 2013-05-03 10:58:00 +0100 | [diff] [blame] | 510 | { "mcp3204", mcp3204 }, |
| 511 | { "mcp3208", mcp3208 }, |
Andrea Galbusera | f686a36 | 2015-07-14 15:36:21 +0200 | [diff] [blame] | 512 | { "mcp3301", mcp3301 }, |
Lukas Wunner | c1375d6 | 2017-09-09 20:32:41 +0200 | [diff] [blame] | 513 | { "mcp3550-50", mcp3550_50 }, |
| 514 | { "mcp3550-60", mcp3550_60 }, |
| 515 | { "mcp3551", mcp3551 }, |
| 516 | { "mcp3553", mcp3553 }, |
Oskar Andero | f5ce4a7 | 2013-05-03 10:58:00 +0100 | [diff] [blame] | 517 | { } |
| 518 | }; |
| 519 | MODULE_DEVICE_TABLE(spi, mcp320x_id); |
| 520 | |
| 521 | static struct spi_driver mcp320x_driver = { |
| 522 | .driver = { |
| 523 | .name = "mcp320x", |
Javier Martinez Canillas | ab6ff6c | 2015-08-20 09:07:26 +0200 | [diff] [blame] | 524 | .of_match_table = of_match_ptr(mcp320x_dt_ids), |
Oskar Andero | f5ce4a7 | 2013-05-03 10:58:00 +0100 | [diff] [blame] | 525 | }, |
| 526 | .probe = mcp320x_probe, |
| 527 | .remove = mcp320x_remove, |
| 528 | .id_table = mcp320x_id, |
| 529 | }; |
| 530 | module_spi_driver(mcp320x_driver); |
| 531 | |
| 532 | MODULE_AUTHOR("Oskar Andero <oskar.andero@gmail.com>"); |
Lukas Wunner | c1375d6 | 2017-09-09 20:32:41 +0200 | [diff] [blame] | 533 | MODULE_DESCRIPTION("Microchip Technology MCP3x01/02/04/08 and MCP3550/1/3"); |
Oskar Andero | f5ce4a7 | 2013-05-03 10:58:00 +0100 | [diff] [blame] | 534 | MODULE_LICENSE("GPL v2"); |