^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1) // SPDX-License-Identifier: GPL-2.0-only
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 2) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 3) * ltc2497.c - Driver for Analog Devices/Linear Technology LTC2497 ADC
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 4) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 5) * Copyright (C) 2017 Analog Devices Inc.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 6) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 7) * Datasheet: http://cds.linear.com/docs/en/datasheet/2497fd.pdf
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 8) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 9)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 10) #include <linux/i2c.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 11) #include <linux/iio/iio.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 12) #include <linux/iio/driver.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 13) #include <linux/module.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 14) #include <linux/mod_devicetable.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 15)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 16) #include "ltc2497.h"
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 17)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 18) struct ltc2497_driverdata {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 19) /* this must be the first member */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 20) struct ltc2497core_driverdata common_ddata;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 21) struct i2c_client *client;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 22) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 23) * DMA (thus cache coherency maintenance) requires the
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 24) * transfer buffers to live in their own cache lines.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 25) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 26) __be32 buf ____cacheline_aligned;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 27) };
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 28)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 29) static int ltc2497_result_and_measure(struct ltc2497core_driverdata *ddata,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 30) u8 address, int *val)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 31) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 32) struct ltc2497_driverdata *st =
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 33) container_of(ddata, struct ltc2497_driverdata, common_ddata);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 34) int ret;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 35)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 36) if (val) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 37) ret = i2c_master_recv(st->client, (char *)&st->buf, 3);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 38) if (ret < 0) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 39) dev_err(&st->client->dev, "i2c_master_recv failed\n");
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 40) return ret;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 41) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 42)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 43) *val = (be32_to_cpu(st->buf) >> 14) - (1 << 17);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 44) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 45)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 46) ret = i2c_smbus_write_byte(st->client,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 47) LTC2497_ENABLE | address);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 48) if (ret)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 49) dev_err(&st->client->dev, "i2c transfer failed: %pe\n",
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 50) ERR_PTR(ret));
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 51) return ret;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 52) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 53)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 54) static int ltc2497_probe(struct i2c_client *client,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 55) const struct i2c_device_id *id)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 56) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 57) struct iio_dev *indio_dev;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 58) struct ltc2497_driverdata *st;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 59) struct device *dev = &client->dev;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 60)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 61) if (!i2c_check_functionality(client->adapter, I2C_FUNC_I2C |
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 62) I2C_FUNC_SMBUS_WRITE_BYTE))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 63) return -EOPNOTSUPP;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 64)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 65) indio_dev = devm_iio_device_alloc(dev, sizeof(*st));
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 66) if (!indio_dev)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 67) return -ENOMEM;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 68)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 69) st = iio_priv(indio_dev);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 70) i2c_set_clientdata(client, indio_dev);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 71) st->client = client;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 72) st->common_ddata.result_and_measure = ltc2497_result_and_measure;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 73)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 74) return ltc2497core_probe(dev, indio_dev);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 75) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 76)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 77) static int ltc2497_remove(struct i2c_client *client)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 78) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 79) struct iio_dev *indio_dev = i2c_get_clientdata(client);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 80)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 81) ltc2497core_remove(indio_dev);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 82)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 83) return 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 84) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 85)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 86) static const struct i2c_device_id ltc2497_id[] = {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 87) { "ltc2497", 0 },
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 88) { }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 89) };
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 90) MODULE_DEVICE_TABLE(i2c, ltc2497_id);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 91)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 92) static const struct of_device_id ltc2497_of_match[] = {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 93) { .compatible = "lltc,ltc2497", },
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 94) {},
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 95) };
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 96) MODULE_DEVICE_TABLE(of, ltc2497_of_match);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 97)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 98) static struct i2c_driver ltc2497_driver = {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 99) .driver = {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 100) .name = "ltc2497",
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 101) .of_match_table = ltc2497_of_match,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 102) },
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 103) .probe = ltc2497_probe,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 104) .remove = ltc2497_remove,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 105) .id_table = ltc2497_id,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 106) };
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 107) module_i2c_driver(ltc2497_driver);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 108)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 109) MODULE_AUTHOR("Michael Hennerich <michael.hennerich@analog.com>");
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 110) MODULE_DESCRIPTION("Linear Technology LTC2497 ADC driver");
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 111) MODULE_LICENSE("GPL v2");
Orange Pi5 kernel
Deprecated Linux kernel 5.10.110 for OrangePi 5/5B/5+ boards
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