^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1) // SPDX-License-Identifier: GPL-2.0
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 2) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 3) * Sensirion SCD30 carbon dioxide sensor i2c driver
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 4) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 5) * Copyright (c) 2020 Tomasz Duszynski <tomasz.duszynski@octakon.com>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 6) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 7) * I2C slave address: 0x61
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 8) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 9) #include <linux/crc8.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 10) #include <linux/device.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 11) #include <linux/errno.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 12) #include <linux/i2c.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 13) #include <linux/mod_devicetable.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 14) #include <linux/module.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 15) #include <linux/types.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 16) #include <asm/unaligned.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 17)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 18) #include "scd30.h"
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 19)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 20) #define SCD30_I2C_MAX_BUF_SIZE 18
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 21) #define SCD30_I2C_CRC8_POLYNOMIAL 0x31
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 22)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 23) static u16 scd30_i2c_cmd_lookup_tbl[] = {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 24) [CMD_START_MEAS] = 0x0010,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 25) [CMD_STOP_MEAS] = 0x0104,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 26) [CMD_MEAS_INTERVAL] = 0x4600,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 27) [CMD_MEAS_READY] = 0x0202,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 28) [CMD_READ_MEAS] = 0x0300,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 29) [CMD_ASC] = 0x5306,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 30) [CMD_FRC] = 0x5204,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 31) [CMD_TEMP_OFFSET] = 0x5403,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 32) [CMD_FW_VERSION] = 0xd100,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 33) [CMD_RESET] = 0xd304,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 34) };
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 35)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 36) DECLARE_CRC8_TABLE(scd30_i2c_crc8_tbl);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 37)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 38) static int scd30_i2c_xfer(struct scd30_state *state, char *txbuf, int txsize,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 39) char *rxbuf, int rxsize)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 40) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 41) struct i2c_client *client = to_i2c_client(state->dev);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 42) int ret;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 43)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 44) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 45) * repeated start is not supported hence instead of sending two i2c
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 46) * messages in a row we send one by one
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 47) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 48) ret = i2c_master_send(client, txbuf, txsize);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 49) if (ret < 0)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 50) return ret;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 51) if (ret != txsize)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 52) return -EIO;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 53)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 54) if (!rxbuf)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 55) return 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 56)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 57) ret = i2c_master_recv(client, rxbuf, rxsize);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 58) if (ret < 0)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 59) return ret;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 60) if (ret != rxsize)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 61) return -EIO;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 62)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 63) return 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 64) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 65)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 66) static int scd30_i2c_command(struct scd30_state *state, enum scd30_cmd cmd, u16 arg,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 67) void *response, int size)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 68) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 69) char buf[SCD30_I2C_MAX_BUF_SIZE];
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 70) char *rsp = response;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 71) int i, ret;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 72) char crc;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 73)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 74) put_unaligned_be16(scd30_i2c_cmd_lookup_tbl[cmd], buf);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 75) i = 2;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 76)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 77) if (rsp) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 78) /* each two bytes are followed by a crc8 */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 79) size += size / 2;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 80) } else {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 81) put_unaligned_be16(arg, buf + i);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 82) crc = crc8(scd30_i2c_crc8_tbl, buf + i, 2, CRC8_INIT_VALUE);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 83) i += 2;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 84) buf[i] = crc;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 85) i += 1;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 86)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 87) /* commands below don't take an argument */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 88) if ((cmd == CMD_STOP_MEAS) || (cmd == CMD_RESET))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 89) i -= 3;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 90) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 91)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 92) ret = scd30_i2c_xfer(state, buf, i, buf, size);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 93) if (ret)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 94) return ret;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 95)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 96) /* validate received data and strip off crc bytes */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 97) for (i = 0; i < size; i += 3) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 98) crc = crc8(scd30_i2c_crc8_tbl, buf + i, 2, CRC8_INIT_VALUE);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 99) if (crc != buf[i + 2]) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 100) dev_err(state->dev, "data integrity check failed\n");
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 101) return -EIO;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 102) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 103)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 104) *rsp++ = buf[i];
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 105) *rsp++ = buf[i + 1];
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 106) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 107)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 108) return 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 109) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 110)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 111) static int scd30_i2c_probe(struct i2c_client *client)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 112) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 113) if (!i2c_check_functionality(client->adapter, I2C_FUNC_I2C))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 114) return -EOPNOTSUPP;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 115)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 116) crc8_populate_msb(scd30_i2c_crc8_tbl, SCD30_I2C_CRC8_POLYNOMIAL);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 117)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 118) return scd30_probe(&client->dev, client->irq, client->name, NULL, scd30_i2c_command);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 119) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 120)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 121) static const struct of_device_id scd30_i2c_of_match[] = {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 122) { .compatible = "sensirion,scd30" },
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 123) { }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 124) };
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 125) MODULE_DEVICE_TABLE(of, scd30_i2c_of_match);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 126)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 127) static struct i2c_driver scd30_i2c_driver = {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 128) .driver = {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 129) .name = KBUILD_MODNAME,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 130) .of_match_table = scd30_i2c_of_match,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 131) .pm = &scd30_pm_ops,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 132) },
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 133) .probe_new = scd30_i2c_probe,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 134) };
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 135) module_i2c_driver(scd30_i2c_driver);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 136)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 137) MODULE_AUTHOR("Tomasz Duszynski <tomasz.duszynski@octakon.com>");
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 138) MODULE_DESCRIPTION("Sensirion SCD30 carbon dioxide sensor i2c driver");
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 139) MODULE_LICENSE("GPL v2");
Orange Pi5 kernel
Deprecated Linux kernel 5.10.110 for OrangePi 5/5B/5+ boards
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