1d2912cb1SThomas Gleixner // SPDX-License-Identifier: GPL-2.0-only 2f5ce4a7aSOskar Andero /* 3f5ce4a7aSOskar Andero * Copyright (C) 2013 Oskar Andero <oskar.andero@gmail.com> 4b12206e9SSøren Andersen * Copyright (C) 2014 Rose Technology 5b12206e9SSøren Andersen * Allan Bendorff Jensen <abj@rosetechnology.dk> 6b12206e9SSøren Andersen * Soren Andersen <san@rosetechnology.dk> 7f5ce4a7aSOskar Andero * 8b12206e9SSøren Andersen * Driver for following ADC chips from Microchip Technology's: 9b12206e9SSøren Andersen * 10 Bit converter 10b12206e9SSøren Andersen * MCP3001 11b12206e9SSøren Andersen * MCP3002 12b12206e9SSøren Andersen * MCP3004 13b12206e9SSøren Andersen * MCP3008 14b12206e9SSøren Andersen * ------------ 15b12206e9SSøren Andersen * 12 bit converter 16b12206e9SSøren Andersen * MCP3201 17b12206e9SSøren Andersen * MCP3202 18b12206e9SSøren Andersen * MCP3204 19b12206e9SSøren Andersen * MCP3208 20b12206e9SSøren Andersen * ------------ 21e6f47943SLukas Wunner * 13 bit converter 22e6f47943SLukas Wunner * MCP3301 23c1375d67SLukas Wunner * ------------ 24c1375d67SLukas Wunner * 22 bit converter 25c1375d67SLukas Wunner * MCP3550 26c1375d67SLukas Wunner * MCP3551 27c1375d67SLukas Wunner * MCP3553 28b12206e9SSøren Andersen * 29f5ce4a7aSOskar Andero * Datasheet can be found here: 303593cd53SAlexander A. Klimov * https://ww1.microchip.com/downloads/en/DeviceDoc/21293C.pdf mcp3001 313593cd53SAlexander A. Klimov * https://ww1.microchip.com/downloads/en/DeviceDoc/21294E.pdf mcp3002 323593cd53SAlexander A. Klimov * https://ww1.microchip.com/downloads/en/DeviceDoc/21295d.pdf mcp3004/08 33b12206e9SSøren Andersen * http://ww1.microchip.com/downloads/en/DeviceDoc/21290D.pdf mcp3201 34b12206e9SSøren Andersen * http://ww1.microchip.com/downloads/en/DeviceDoc/21034D.pdf mcp3202 35b12206e9SSøren Andersen * http://ww1.microchip.com/downloads/en/DeviceDoc/21298c.pdf mcp3204/08 363593cd53SAlexander A. Klimov * https://ww1.microchip.com/downloads/en/DeviceDoc/21700E.pdf mcp3301 37c1375d67SLukas Wunner * http://ww1.microchip.com/downloads/en/DeviceDoc/21950D.pdf mcp3550/1/3 38f5ce4a7aSOskar Andero */ 39f5ce4a7aSOskar Andero 40f5ce4a7aSOskar Andero #include <linux/err.h> 41b12206e9SSøren Andersen #include <linux/delay.h> 42f5ce4a7aSOskar Andero #include <linux/spi/spi.h> 43f5ce4a7aSOskar Andero #include <linux/module.h> 44016d271eSJonathan Cameron #include <linux/mod_devicetable.h> 45f5ce4a7aSOskar Andero #include <linux/iio/iio.h> 46f5ce4a7aSOskar Andero #include <linux/regulator/consumer.h> 47f5ce4a7aSOskar Andero 48f5ce4a7aSOskar Andero enum { 49b12206e9SSøren Andersen mcp3001, 50b12206e9SSøren Andersen mcp3002, 51b12206e9SSøren Andersen mcp3004, 52b12206e9SSøren Andersen mcp3008, 53b12206e9SSøren Andersen mcp3201, 54b12206e9SSøren Andersen mcp3202, 55f5ce4a7aSOskar Andero mcp3204, 56f5ce4a7aSOskar Andero mcp3208, 57f686a36bSAndrea Galbusera mcp3301, 58c1375d67SLukas Wunner mcp3550_50, 59c1375d67SLukas Wunner mcp3550_60, 60c1375d67SLukas Wunner mcp3551, 61c1375d67SLukas Wunner mcp3553, 62f5ce4a7aSOskar Andero }; 63f5ce4a7aSOskar Andero 64b12206e9SSøren Andersen struct mcp320x_chip_info { 65b12206e9SSøren Andersen const struct iio_chan_spec *channels; 66b12206e9SSøren Andersen unsigned int num_channels; 67b12206e9SSøren Andersen unsigned int resolution; 68c1375d67SLukas Wunner unsigned int conv_time; /* usec */ 69b12206e9SSøren Andersen }; 70b12206e9SSøren Andersen 719c84c910SLukas Wunner /** 729c84c910SLukas Wunner * struct mcp320x - Microchip SPI ADC instance 739c84c910SLukas Wunner * @spi: SPI slave (parent of the IIO device) 749c84c910SLukas Wunner * @msg: SPI message to select a channel and receive a value from the ADC 759c84c910SLukas Wunner * @transfer: SPI transfers used by @msg 76c1375d67SLukas Wunner * @start_conv_msg: SPI message to start a conversion by briefly asserting CS 77c1375d67SLukas Wunner * @start_conv_transfer: SPI transfer used by @start_conv_msg 789c84c910SLukas Wunner * @reg: regulator generating Vref 799c84c910SLukas Wunner * @lock: protects read sequences 809c84c910SLukas Wunner * @chip_info: ADC properties 819c84c910SLukas Wunner * @tx_buf: buffer for @transfer[0] (not used on single-channel converters) 829c84c910SLukas Wunner * @rx_buf: buffer for @transfer[1] 839c84c910SLukas Wunner */ 84f5ce4a7aSOskar Andero struct mcp320x { 85f5ce4a7aSOskar Andero struct spi_device *spi; 86f5ce4a7aSOskar Andero struct spi_message msg; 87f5ce4a7aSOskar Andero struct spi_transfer transfer[2]; 88c1375d67SLukas Wunner struct spi_message start_conv_msg; 89c1375d67SLukas Wunner struct spi_transfer start_conv_transfer; 90f5ce4a7aSOskar Andero 91f5ce4a7aSOskar Andero struct regulator *reg; 92f5ce4a7aSOskar Andero struct mutex lock; 93b12206e9SSøren Andersen const struct mcp320x_chip_info *chip_info; 940e81bc99SMichael Welling 95e770f780SJonathan Cameron u8 tx_buf __aligned(IIO_DMA_MINALIGN); 96c1375d67SLukas Wunner u8 rx_buf[4]; 97f5ce4a7aSOskar Andero }; 98f5ce4a7aSOskar Andero 99b12206e9SSøren Andersen static int mcp320x_channel_to_tx_data(int device_index, 100b12206e9SSøren Andersen const unsigned int channel, bool differential) 101b12206e9SSøren Andersen { 102b12206e9SSøren Andersen int start_bit = 1; 103b12206e9SSøren Andersen 104b12206e9SSøren Andersen switch (device_index) { 105b12206e9SSøren Andersen case mcp3002: 106b12206e9SSøren Andersen case mcp3202: 107b12206e9SSøren Andersen return ((start_bit << 4) | (!differential << 3) | 108b12206e9SSøren Andersen (channel << 2)); 109b12206e9SSøren Andersen case mcp3004: 110b12206e9SSøren Andersen case mcp3204: 111b12206e9SSøren Andersen case mcp3008: 112b12206e9SSøren Andersen case mcp3208: 113b12206e9SSøren Andersen return ((start_bit << 6) | (!differential << 5) | 114b12206e9SSøren Andersen (channel << 2)); 115b12206e9SSøren Andersen default: 116b12206e9SSøren Andersen return -EINVAL; 117b12206e9SSøren Andersen } 118b12206e9SSøren Andersen } 119b12206e9SSøren Andersen 120b12206e9SSøren Andersen static int mcp320x_adc_conversion(struct mcp320x *adc, u8 channel, 121e6f47943SLukas Wunner bool differential, int device_index, int *val) 122f5ce4a7aSOskar Andero { 123f5ce4a7aSOskar Andero int ret; 124f5ce4a7aSOskar Andero 125c1375d67SLukas Wunner if (adc->chip_info->conv_time) { 126c1375d67SLukas Wunner ret = spi_sync(adc->spi, &adc->start_conv_msg); 127c1375d67SLukas Wunner if (ret < 0) 128c1375d67SLukas Wunner return ret; 129c1375d67SLukas Wunner 130c1375d67SLukas Wunner usleep_range(adc->chip_info->conv_time, 131c1375d67SLukas Wunner adc->chip_info->conv_time + 100); 132c1375d67SLukas Wunner } 133c1375d67SLukas Wunner 134ea910318SLukas Wunner memset(&adc->rx_buf, 0, sizeof(adc->rx_buf)); 135ea910318SLukas Wunner if (adc->chip_info->num_channels > 1) 136ea910318SLukas Wunner adc->tx_buf = mcp320x_channel_to_tx_data(device_index, channel, 137ea910318SLukas Wunner differential); 138b12206e9SSøren Andersen 139f5ce4a7aSOskar Andero ret = spi_sync(adc->spi, &adc->msg); 140f5ce4a7aSOskar Andero if (ret < 0) 141f5ce4a7aSOskar Andero return ret; 142f5ce4a7aSOskar Andero 143b12206e9SSøren Andersen switch (device_index) { 144b12206e9SSøren Andersen case mcp3001: 145e6f47943SLukas Wunner *val = (adc->rx_buf[0] << 5 | adc->rx_buf[1] >> 3); 146e6f47943SLukas Wunner return 0; 147b12206e9SSøren Andersen case mcp3002: 148b12206e9SSøren Andersen case mcp3004: 149b12206e9SSøren Andersen case mcp3008: 150e6f47943SLukas Wunner *val = (adc->rx_buf[0] << 2 | adc->rx_buf[1] >> 6); 151e6f47943SLukas Wunner return 0; 152b12206e9SSøren Andersen case mcp3201: 153e6f47943SLukas Wunner *val = (adc->rx_buf[0] << 7 | adc->rx_buf[1] >> 1); 154e6f47943SLukas Wunner return 0; 155b12206e9SSøren Andersen case mcp3202: 156b12206e9SSøren Andersen case mcp3204: 157b12206e9SSøren Andersen case mcp3208: 158e6f47943SLukas Wunner *val = (adc->rx_buf[0] << 4 | adc->rx_buf[1] >> 4); 159e6f47943SLukas Wunner return 0; 160f686a36bSAndrea Galbusera case mcp3301: 161e6f47943SLukas Wunner *val = sign_extend32((adc->rx_buf[0] & 0x1f) << 8 162e6f47943SLukas Wunner | adc->rx_buf[1], 12); 163e6f47943SLukas Wunner return 0; 164c1375d67SLukas Wunner case mcp3550_50: 165c1375d67SLukas Wunner case mcp3550_60: 166c1375d67SLukas Wunner case mcp3551: 167c1375d67SLukas Wunner case mcp3553: { 1689299b503SJonathan Cameron u32 raw = be32_to_cpup((__be32 *)adc->rx_buf); 169c1375d67SLukas Wunner 170c1375d67SLukas Wunner if (!(adc->spi->mode & SPI_CPOL)) 171c1375d67SLukas Wunner raw <<= 1; /* strip Data Ready bit in SPI mode 0,0 */ 172c1375d67SLukas Wunner 173c1375d67SLukas Wunner /* 174c1375d67SLukas Wunner * If the input is within -vref and vref, bit 21 is the sign. 175c1375d67SLukas Wunner * Up to 12% overrange or underrange are allowed, in which case 176c1375d67SLukas Wunner * bit 23 is the sign and bit 0 to 21 is the value. 177c1375d67SLukas Wunner */ 178c1375d67SLukas Wunner raw >>= 8; 179c1375d67SLukas Wunner if (raw & BIT(22) && raw & BIT(23)) 180c1375d67SLukas Wunner return -EIO; /* cannot have overrange AND underrange */ 181c1375d67SLukas Wunner else if (raw & BIT(22)) 182c1375d67SLukas Wunner raw &= ~BIT(22); /* overrange */ 183c1375d67SLukas Wunner else if (raw & BIT(23) || raw & BIT(21)) 184c1375d67SLukas Wunner raw |= GENMASK(31, 22); /* underrange or negative */ 185c1375d67SLukas Wunner 186c1375d67SLukas Wunner *val = (s32)raw; 187c1375d67SLukas Wunner return 0; 188c1375d67SLukas Wunner } 189b12206e9SSøren Andersen default: 190b12206e9SSøren Andersen return -EINVAL; 191b12206e9SSøren Andersen } 192f5ce4a7aSOskar Andero } 193f5ce4a7aSOskar Andero 194f5ce4a7aSOskar Andero static int mcp320x_read_raw(struct iio_dev *indio_dev, 195f5ce4a7aSOskar Andero struct iio_chan_spec const *channel, int *val, 196f5ce4a7aSOskar Andero int *val2, long mask) 197f5ce4a7aSOskar Andero { 198f5ce4a7aSOskar Andero struct mcp320x *adc = iio_priv(indio_dev); 199f5ce4a7aSOskar Andero int ret = -EINVAL; 200b12206e9SSøren Andersen int device_index = 0; 201f5ce4a7aSOskar Andero 202f5ce4a7aSOskar Andero mutex_lock(&adc->lock); 203f5ce4a7aSOskar Andero 204b12206e9SSøren Andersen device_index = spi_get_device_id(adc->spi)->driver_data; 205b12206e9SSøren Andersen 206f5ce4a7aSOskar Andero switch (mask) { 207f5ce4a7aSOskar Andero case IIO_CHAN_INFO_RAW: 208b12206e9SSøren Andersen ret = mcp320x_adc_conversion(adc, channel->address, 209e6f47943SLukas Wunner channel->differential, device_index, val); 210f5ce4a7aSOskar Andero if (ret < 0) 211f5ce4a7aSOskar Andero goto out; 212f5ce4a7aSOskar Andero 213f5ce4a7aSOskar Andero ret = IIO_VAL_INT; 214f5ce4a7aSOskar Andero break; 215f5ce4a7aSOskar Andero 216f5ce4a7aSOskar Andero case IIO_CHAN_INFO_SCALE: 217f5ce4a7aSOskar Andero ret = regulator_get_voltage(adc->reg); 218f5ce4a7aSOskar Andero if (ret < 0) 219f5ce4a7aSOskar Andero goto out; 220f5ce4a7aSOskar Andero 221b12206e9SSøren Andersen /* convert regulator output voltage to mV */ 222f5ce4a7aSOskar Andero *val = ret / 1000; 223b12206e9SSøren Andersen *val2 = adc->chip_info->resolution; 224f5ce4a7aSOskar Andero ret = IIO_VAL_FRACTIONAL_LOG2; 225f5ce4a7aSOskar Andero break; 226f5ce4a7aSOskar Andero } 227f5ce4a7aSOskar Andero 228f5ce4a7aSOskar Andero out: 229f5ce4a7aSOskar Andero mutex_unlock(&adc->lock); 230f5ce4a7aSOskar Andero 231f5ce4a7aSOskar Andero return ret; 232f5ce4a7aSOskar Andero } 233f5ce4a7aSOskar Andero 234f5ce4a7aSOskar Andero #define MCP320X_VOLTAGE_CHANNEL(num) \ 235f5ce4a7aSOskar Andero { \ 236f5ce4a7aSOskar Andero .type = IIO_VOLTAGE, \ 237f5ce4a7aSOskar Andero .indexed = 1, \ 238f5ce4a7aSOskar Andero .channel = (num), \ 239f5ce4a7aSOskar Andero .address = (num), \ 240f5ce4a7aSOskar Andero .info_mask_separate = BIT(IIO_CHAN_INFO_RAW), \ 241f5ce4a7aSOskar Andero .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE) \ 242f5ce4a7aSOskar Andero } 243f5ce4a7aSOskar Andero 2444ea71e5cSAkinobu Mita #define MCP320X_VOLTAGE_CHANNEL_DIFF(chan1, chan2) \ 245f5ce4a7aSOskar Andero { \ 246f5ce4a7aSOskar Andero .type = IIO_VOLTAGE, \ 247f5ce4a7aSOskar Andero .indexed = 1, \ 2484ea71e5cSAkinobu Mita .channel = (chan1), \ 2494ea71e5cSAkinobu Mita .channel2 = (chan2), \ 2504ea71e5cSAkinobu Mita .address = (chan1), \ 251f5ce4a7aSOskar Andero .differential = 1, \ 252f5ce4a7aSOskar Andero .info_mask_separate = BIT(IIO_CHAN_INFO_RAW), \ 253f5ce4a7aSOskar Andero .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE) \ 254f5ce4a7aSOskar Andero } 255f5ce4a7aSOskar Andero 256b12206e9SSøren Andersen static const struct iio_chan_spec mcp3201_channels[] = { 2574ea71e5cSAkinobu Mita MCP320X_VOLTAGE_CHANNEL_DIFF(0, 1), 258b12206e9SSøren Andersen }; 259b12206e9SSøren Andersen 260b12206e9SSøren Andersen static const struct iio_chan_spec mcp3202_channels[] = { 261b12206e9SSøren Andersen MCP320X_VOLTAGE_CHANNEL(0), 262b12206e9SSøren Andersen MCP320X_VOLTAGE_CHANNEL(1), 2634ea71e5cSAkinobu Mita MCP320X_VOLTAGE_CHANNEL_DIFF(0, 1), 2644ea71e5cSAkinobu Mita MCP320X_VOLTAGE_CHANNEL_DIFF(1, 0), 265b12206e9SSøren Andersen }; 266b12206e9SSøren Andersen 267f5ce4a7aSOskar Andero static const struct iio_chan_spec mcp3204_channels[] = { 268f5ce4a7aSOskar Andero MCP320X_VOLTAGE_CHANNEL(0), 269f5ce4a7aSOskar Andero MCP320X_VOLTAGE_CHANNEL(1), 270f5ce4a7aSOskar Andero MCP320X_VOLTAGE_CHANNEL(2), 271f5ce4a7aSOskar Andero MCP320X_VOLTAGE_CHANNEL(3), 2724ea71e5cSAkinobu Mita MCP320X_VOLTAGE_CHANNEL_DIFF(0, 1), 2734ea71e5cSAkinobu Mita MCP320X_VOLTAGE_CHANNEL_DIFF(1, 0), 2744ea71e5cSAkinobu Mita MCP320X_VOLTAGE_CHANNEL_DIFF(2, 3), 2754ea71e5cSAkinobu Mita MCP320X_VOLTAGE_CHANNEL_DIFF(3, 2), 276f5ce4a7aSOskar Andero }; 277f5ce4a7aSOskar Andero 278f5ce4a7aSOskar Andero static const struct iio_chan_spec mcp3208_channels[] = { 279f5ce4a7aSOskar Andero MCP320X_VOLTAGE_CHANNEL(0), 280f5ce4a7aSOskar Andero MCP320X_VOLTAGE_CHANNEL(1), 281f5ce4a7aSOskar Andero MCP320X_VOLTAGE_CHANNEL(2), 282f5ce4a7aSOskar Andero MCP320X_VOLTAGE_CHANNEL(3), 283f5ce4a7aSOskar Andero MCP320X_VOLTAGE_CHANNEL(4), 284f5ce4a7aSOskar Andero MCP320X_VOLTAGE_CHANNEL(5), 285f5ce4a7aSOskar Andero MCP320X_VOLTAGE_CHANNEL(6), 286f5ce4a7aSOskar Andero MCP320X_VOLTAGE_CHANNEL(7), 2874ea71e5cSAkinobu Mita MCP320X_VOLTAGE_CHANNEL_DIFF(0, 1), 2884ea71e5cSAkinobu Mita MCP320X_VOLTAGE_CHANNEL_DIFF(1, 0), 2894ea71e5cSAkinobu Mita MCP320X_VOLTAGE_CHANNEL_DIFF(2, 3), 2904ea71e5cSAkinobu Mita MCP320X_VOLTAGE_CHANNEL_DIFF(3, 2), 2914ea71e5cSAkinobu Mita MCP320X_VOLTAGE_CHANNEL_DIFF(4, 5), 2924ea71e5cSAkinobu Mita MCP320X_VOLTAGE_CHANNEL_DIFF(5, 4), 2934ea71e5cSAkinobu Mita MCP320X_VOLTAGE_CHANNEL_DIFF(6, 7), 2944ea71e5cSAkinobu Mita MCP320X_VOLTAGE_CHANNEL_DIFF(7, 6), 295f5ce4a7aSOskar Andero }; 296f5ce4a7aSOskar Andero 297f5ce4a7aSOskar Andero static const struct iio_info mcp320x_info = { 298f5ce4a7aSOskar Andero .read_raw = mcp320x_read_raw, 299f5ce4a7aSOskar Andero }; 300f5ce4a7aSOskar Andero 301b12206e9SSøren Andersen static const struct mcp320x_chip_info mcp320x_chip_infos[] = { 302b12206e9SSøren Andersen [mcp3001] = { 303b12206e9SSøren Andersen .channels = mcp3201_channels, 304b12206e9SSøren Andersen .num_channels = ARRAY_SIZE(mcp3201_channels), 305b12206e9SSøren Andersen .resolution = 10 306b12206e9SSøren Andersen }, 307b12206e9SSøren Andersen [mcp3002] = { 308b12206e9SSøren Andersen .channels = mcp3202_channels, 309b12206e9SSøren Andersen .num_channels = ARRAY_SIZE(mcp3202_channels), 310b12206e9SSøren Andersen .resolution = 10 311b12206e9SSøren Andersen }, 312b12206e9SSøren Andersen [mcp3004] = { 313b12206e9SSøren Andersen .channels = mcp3204_channels, 314b12206e9SSøren Andersen .num_channels = ARRAY_SIZE(mcp3204_channels), 315b12206e9SSøren Andersen .resolution = 10 316b12206e9SSøren Andersen }, 317b12206e9SSøren Andersen [mcp3008] = { 318b12206e9SSøren Andersen .channels = mcp3208_channels, 319b12206e9SSøren Andersen .num_channels = ARRAY_SIZE(mcp3208_channels), 320b12206e9SSøren Andersen .resolution = 10 321b12206e9SSøren Andersen }, 322b12206e9SSøren Andersen [mcp3201] = { 323b12206e9SSøren Andersen .channels = mcp3201_channels, 324b12206e9SSøren Andersen .num_channels = ARRAY_SIZE(mcp3201_channels), 325b12206e9SSøren Andersen .resolution = 12 326b12206e9SSøren Andersen }, 327b12206e9SSøren Andersen [mcp3202] = { 328b12206e9SSøren Andersen .channels = mcp3202_channels, 329b12206e9SSøren Andersen .num_channels = ARRAY_SIZE(mcp3202_channels), 330b12206e9SSøren Andersen .resolution = 12 331b12206e9SSøren Andersen }, 332f5ce4a7aSOskar Andero [mcp3204] = { 333f5ce4a7aSOskar Andero .channels = mcp3204_channels, 334b12206e9SSøren Andersen .num_channels = ARRAY_SIZE(mcp3204_channels), 335b12206e9SSøren Andersen .resolution = 12 336f5ce4a7aSOskar Andero }, 337f5ce4a7aSOskar Andero [mcp3208] = { 338f5ce4a7aSOskar Andero .channels = mcp3208_channels, 339b12206e9SSøren Andersen .num_channels = ARRAY_SIZE(mcp3208_channels), 340b12206e9SSøren Andersen .resolution = 12 341f5ce4a7aSOskar Andero }, 342f686a36bSAndrea Galbusera [mcp3301] = { 343f686a36bSAndrea Galbusera .channels = mcp3201_channels, 344f686a36bSAndrea Galbusera .num_channels = ARRAY_SIZE(mcp3201_channels), 345f686a36bSAndrea Galbusera .resolution = 13 346f686a36bSAndrea Galbusera }, 347c1375d67SLukas Wunner [mcp3550_50] = { 348c1375d67SLukas Wunner .channels = mcp3201_channels, 349c1375d67SLukas Wunner .num_channels = ARRAY_SIZE(mcp3201_channels), 350c1375d67SLukas Wunner .resolution = 21, 351c1375d67SLukas Wunner /* 2% max deviation + 144 clock periods to exit shutdown */ 352c1375d67SLukas Wunner .conv_time = 80000 * 1.02 + 144000 / 102.4, 353c1375d67SLukas Wunner }, 354c1375d67SLukas Wunner [mcp3550_60] = { 355c1375d67SLukas Wunner .channels = mcp3201_channels, 356c1375d67SLukas Wunner .num_channels = ARRAY_SIZE(mcp3201_channels), 357c1375d67SLukas Wunner .resolution = 21, 358c1375d67SLukas Wunner .conv_time = 66670 * 1.02 + 144000 / 122.88, 359c1375d67SLukas Wunner }, 360c1375d67SLukas Wunner [mcp3551] = { 361c1375d67SLukas Wunner .channels = mcp3201_channels, 362c1375d67SLukas Wunner .num_channels = ARRAY_SIZE(mcp3201_channels), 363c1375d67SLukas Wunner .resolution = 21, 364c1375d67SLukas Wunner .conv_time = 73100 * 1.02 + 144000 / 112.64, 365c1375d67SLukas Wunner }, 366c1375d67SLukas Wunner [mcp3553] = { 367c1375d67SLukas Wunner .channels = mcp3201_channels, 368c1375d67SLukas Wunner .num_channels = ARRAY_SIZE(mcp3201_channels), 369c1375d67SLukas Wunner .resolution = 21, 370c1375d67SLukas Wunner .conv_time = 16670 * 1.02 + 144000 / 122.88, 371c1375d67SLukas Wunner }, 372f5ce4a7aSOskar Andero }; 373f5ce4a7aSOskar Andero 374*58efe761SArturas Moskvinas static void mcp320x_regulator_disable(void *reg) 375*58efe761SArturas Moskvinas { 376*58efe761SArturas Moskvinas regulator_disable(reg); 377*58efe761SArturas Moskvinas } 378*58efe761SArturas Moskvinas 379f5ce4a7aSOskar Andero static int mcp320x_probe(struct spi_device *spi) 380f5ce4a7aSOskar Andero { 381f5ce4a7aSOskar Andero struct iio_dev *indio_dev; 382f5ce4a7aSOskar Andero struct mcp320x *adc; 383b12206e9SSøren Andersen const struct mcp320x_chip_info *chip_info; 384c1375d67SLukas Wunner int ret, device_index; 385f5ce4a7aSOskar Andero 386a726dea5SSachin Kamat indio_dev = devm_iio_device_alloc(&spi->dev, sizeof(*adc)); 387f5ce4a7aSOskar Andero if (!indio_dev) 388f5ce4a7aSOskar Andero return -ENOMEM; 389f5ce4a7aSOskar Andero 390f5ce4a7aSOskar Andero adc = iio_priv(indio_dev); 391f5ce4a7aSOskar Andero adc->spi = spi; 392f5ce4a7aSOskar Andero 393f5ce4a7aSOskar Andero indio_dev->name = spi_get_device_id(spi)->name; 394f5ce4a7aSOskar Andero indio_dev->modes = INDIO_DIRECT_MODE; 395f5ce4a7aSOskar Andero indio_dev->info = &mcp320x_info; 396f5ce4a7aSOskar Andero 397c1375d67SLukas Wunner device_index = spi_get_device_id(spi)->driver_data; 398c1375d67SLukas Wunner chip_info = &mcp320x_chip_infos[device_index]; 399f5ce4a7aSOskar Andero indio_dev->channels = chip_info->channels; 400f5ce4a7aSOskar Andero indio_dev->num_channels = chip_info->num_channels; 401f5ce4a7aSOskar Andero 40241be6a0dSManfred Schlaegl adc->chip_info = chip_info; 40341be6a0dSManfred Schlaegl 404f5ce4a7aSOskar Andero adc->transfer[0].tx_buf = &adc->tx_buf; 405f5ce4a7aSOskar Andero adc->transfer[0].len = sizeof(adc->tx_buf); 406f5ce4a7aSOskar Andero adc->transfer[1].rx_buf = adc->rx_buf; 407c1375d67SLukas Wunner adc->transfer[1].len = DIV_ROUND_UP(chip_info->resolution, 8); 408c1375d67SLukas Wunner 409ea910318SLukas Wunner if (chip_info->num_channels == 1) 410ea910318SLukas Wunner /* single-channel converters are rx only (no MOSI pin) */ 411ea910318SLukas Wunner spi_message_init_with_transfers(&adc->msg, 412ea910318SLukas Wunner &adc->transfer[1], 1); 413ea910318SLukas Wunner else 414f5ce4a7aSOskar Andero spi_message_init_with_transfers(&adc->msg, adc->transfer, 415f5ce4a7aSOskar Andero ARRAY_SIZE(adc->transfer)); 416f5ce4a7aSOskar Andero 417c1375d67SLukas Wunner switch (device_index) { 418c1375d67SLukas Wunner case mcp3550_50: 419c1375d67SLukas Wunner case mcp3550_60: 420c1375d67SLukas Wunner case mcp3551: 421c1375d67SLukas Wunner case mcp3553: 422c1375d67SLukas Wunner /* rx len increases from 24 to 25 bit in SPI mode 0,0 */ 423c1375d67SLukas Wunner if (!(spi->mode & SPI_CPOL)) 424c1375d67SLukas Wunner adc->transfer[1].len++; 425c1375d67SLukas Wunner 426c1375d67SLukas Wunner /* conversions are started by asserting CS pin for 8 usec */ 427eccd0718SSergiu Cuciurean adc->start_conv_transfer.delay.value = 8; 428eccd0718SSergiu Cuciurean adc->start_conv_transfer.delay.unit = SPI_DELAY_UNIT_USECS; 429c1375d67SLukas Wunner spi_message_init_with_transfers(&adc->start_conv_msg, 430c1375d67SLukas Wunner &adc->start_conv_transfer, 1); 431c1375d67SLukas Wunner 432c1375d67SLukas Wunner /* 433c1375d67SLukas Wunner * If CS was previously kept low (continuous conversion mode) 434c1375d67SLukas Wunner * and then changed to high, the chip is in shutdown. 435c1375d67SLukas Wunner * Sometimes it fails to wake from shutdown and clocks out 436c1375d67SLukas Wunner * only 0xffffff. The magic sequence of performing two 437c1375d67SLukas Wunner * conversions without delay between them resets the chip 438c1375d67SLukas Wunner * and ensures all subsequent conversions succeed. 439c1375d67SLukas Wunner */ 440c1375d67SLukas Wunner mcp320x_adc_conversion(adc, 0, 1, device_index, &ret); 441c1375d67SLukas Wunner mcp320x_adc_conversion(adc, 0, 1, device_index, &ret); 442c1375d67SLukas Wunner } 443c1375d67SLukas Wunner 444a726dea5SSachin Kamat adc->reg = devm_regulator_get(&spi->dev, "vref"); 445a726dea5SSachin Kamat if (IS_ERR(adc->reg)) 446a726dea5SSachin Kamat return PTR_ERR(adc->reg); 447f5ce4a7aSOskar Andero 448f5ce4a7aSOskar Andero ret = regulator_enable(adc->reg); 449f5ce4a7aSOskar Andero if (ret < 0) 450a726dea5SSachin Kamat return ret; 451f5ce4a7aSOskar Andero 452*58efe761SArturas Moskvinas ret = devm_add_action_or_reset(&spi->dev, mcp320x_regulator_disable, adc->reg); 453*58efe761SArturas Moskvinas if (ret < 0) 454*58efe761SArturas Moskvinas return ret; 455*58efe761SArturas Moskvinas 456f5ce4a7aSOskar Andero mutex_init(&adc->lock); 457f5ce4a7aSOskar Andero 458*58efe761SArturas Moskvinas return devm_iio_device_register(&spi->dev, indio_dev); 459f5ce4a7aSOskar Andero } 460f5ce4a7aSOskar Andero 461b12206e9SSøren Andersen static const struct of_device_id mcp320x_dt_ids[] = { 4620d0e5384SJavier Martinez Canillas /* NOTE: The use of compatibles with no vendor prefix is deprecated. */ 46335ed9fbfSLukas Wunner { .compatible = "mcp3001" }, 46435ed9fbfSLukas Wunner { .compatible = "mcp3002" }, 46535ed9fbfSLukas Wunner { .compatible = "mcp3004" }, 46635ed9fbfSLukas Wunner { .compatible = "mcp3008" }, 46735ed9fbfSLukas Wunner { .compatible = "mcp3201" }, 46835ed9fbfSLukas Wunner { .compatible = "mcp3202" }, 46935ed9fbfSLukas Wunner { .compatible = "mcp3204" }, 47035ed9fbfSLukas Wunner { .compatible = "mcp3208" }, 47135ed9fbfSLukas Wunner { .compatible = "mcp3301" }, 47235ed9fbfSLukas Wunner { .compatible = "microchip,mcp3001" }, 47335ed9fbfSLukas Wunner { .compatible = "microchip,mcp3002" }, 47435ed9fbfSLukas Wunner { .compatible = "microchip,mcp3004" }, 47535ed9fbfSLukas Wunner { .compatible = "microchip,mcp3008" }, 47635ed9fbfSLukas Wunner { .compatible = "microchip,mcp3201" }, 47735ed9fbfSLukas Wunner { .compatible = "microchip,mcp3202" }, 47835ed9fbfSLukas Wunner { .compatible = "microchip,mcp3204" }, 47935ed9fbfSLukas Wunner { .compatible = "microchip,mcp3208" }, 48035ed9fbfSLukas Wunner { .compatible = "microchip,mcp3301" }, 481c1375d67SLukas Wunner { .compatible = "microchip,mcp3550-50" }, 482c1375d67SLukas Wunner { .compatible = "microchip,mcp3550-60" }, 483c1375d67SLukas Wunner { .compatible = "microchip,mcp3551" }, 484c1375d67SLukas Wunner { .compatible = "microchip,mcp3553" }, 48535ed9fbfSLukas Wunner { } 486b12206e9SSøren Andersen }; 487b12206e9SSøren Andersen MODULE_DEVICE_TABLE(of, mcp320x_dt_ids); 488b12206e9SSøren Andersen 489f5ce4a7aSOskar Andero static const struct spi_device_id mcp320x_id[] = { 490b12206e9SSøren Andersen { "mcp3001", mcp3001 }, 491b12206e9SSøren Andersen { "mcp3002", mcp3002 }, 492b12206e9SSøren Andersen { "mcp3004", mcp3004 }, 493b12206e9SSøren Andersen { "mcp3008", mcp3008 }, 494b12206e9SSøren Andersen { "mcp3201", mcp3201 }, 495b12206e9SSøren Andersen { "mcp3202", mcp3202 }, 496f5ce4a7aSOskar Andero { "mcp3204", mcp3204 }, 497f5ce4a7aSOskar Andero { "mcp3208", mcp3208 }, 498f686a36bSAndrea Galbusera { "mcp3301", mcp3301 }, 499c1375d67SLukas Wunner { "mcp3550-50", mcp3550_50 }, 500c1375d67SLukas Wunner { "mcp3550-60", mcp3550_60 }, 501c1375d67SLukas Wunner { "mcp3551", mcp3551 }, 502c1375d67SLukas Wunner { "mcp3553", mcp3553 }, 503f5ce4a7aSOskar Andero { } 504f5ce4a7aSOskar Andero }; 505f5ce4a7aSOskar Andero MODULE_DEVICE_TABLE(spi, mcp320x_id); 506f5ce4a7aSOskar Andero 507f5ce4a7aSOskar Andero static struct spi_driver mcp320x_driver = { 508f5ce4a7aSOskar Andero .driver = { 509f5ce4a7aSOskar Andero .name = "mcp320x", 510016d271eSJonathan Cameron .of_match_table = mcp320x_dt_ids, 511f5ce4a7aSOskar Andero }, 512f5ce4a7aSOskar Andero .probe = mcp320x_probe, 513f5ce4a7aSOskar Andero .id_table = mcp320x_id, 514f5ce4a7aSOskar Andero }; 515f5ce4a7aSOskar Andero module_spi_driver(mcp320x_driver); 516f5ce4a7aSOskar Andero 517f5ce4a7aSOskar Andero MODULE_AUTHOR("Oskar Andero <oskar.andero@gmail.com>"); 518c1375d67SLukas Wunner MODULE_DESCRIPTION("Microchip Technology MCP3x01/02/04/08 and MCP3550/1/3"); 519f5ce4a7aSOskar Andero MODULE_LICENSE("GPL v2"); 520