^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) * An rtc/i2c driver for the Dallas DS1672
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 4) * Copyright 2005-06 Tower Technologies
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 5) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 6) * Author: Alessandro Zummo <a.zummo@towertech.it>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 7) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 8)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 9) #include <linux/i2c.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 10) #include <linux/rtc.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 11) #include <linux/module.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 12)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 13) /* Registers */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 14)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 15) #define DS1672_REG_CNT_BASE 0
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 16) #define DS1672_REG_CONTROL 4
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 17) #define DS1672_REG_TRICKLE 5
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 18)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 19) #define DS1672_REG_CONTROL_EOSC 0x80
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 20)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 21) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 22) * In the routines that deal directly with the ds1672 hardware, we use
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 23) * rtc_time -- month 0-11, hour 0-23, yr = calendar year-epoch
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 24) * Time is set to UTC.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 25) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 26) static int ds1672_read_time(struct device *dev, struct rtc_time *tm)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 27) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 28) struct i2c_client *client = to_i2c_client(dev);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 29) unsigned long time;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 30) unsigned char addr = DS1672_REG_CONTROL;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 31) unsigned char buf[4];
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 32)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 33) struct i2c_msg msgs[] = {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 34) {/* setup read ptr */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 35) .addr = client->addr,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 36) .len = 1,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 37) .buf = &addr
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 38) },
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 39) {/* read date */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 40) .addr = client->addr,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 41) .flags = I2C_M_RD,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 42) .len = 1,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 43) .buf = buf
^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)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 47) /* read control register */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 48) if ((i2c_transfer(client->adapter, &msgs[0], 2)) != 2) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 49) dev_warn(&client->dev, "Unable to read the control register\n");
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 50) return -EIO;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 51) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 52)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 53) if (buf[0] & DS1672_REG_CONTROL_EOSC) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 54) dev_warn(&client->dev, "Oscillator not enabled. Set time to enable.\n");
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 55) return -EINVAL;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 56) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 57)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 58) addr = DS1672_REG_CNT_BASE;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 59) msgs[1].len = 4;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 60)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 61) /* read date registers */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 62) if ((i2c_transfer(client->adapter, &msgs[0], 2)) != 2) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 63) dev_err(&client->dev, "%s: read error\n", __func__);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 64) return -EIO;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 65) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 66)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 67) dev_dbg(&client->dev,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 68) "%s: raw read data - counters=%02x,%02x,%02x,%02x\n",
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 69) __func__, buf[0], buf[1], buf[2], buf[3]);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 70)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 71) time = ((unsigned long)buf[3] << 24) | (buf[2] << 16) |
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 72) (buf[1] << 8) | buf[0];
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 73)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 74) rtc_time64_to_tm(time, tm);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 75)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 76) dev_dbg(&client->dev, "%s: tm is %ptR\n", __func__, tm);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 77)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 78) return 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 79) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 80)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 81) static int ds1672_set_time(struct device *dev, struct rtc_time *tm)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 82) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 83) struct i2c_client *client = to_i2c_client(dev);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 84) int xfer;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 85) unsigned char buf[6];
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 86) unsigned long secs = rtc_tm_to_time64(tm);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 87)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 88) buf[0] = DS1672_REG_CNT_BASE;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 89) buf[1] = secs & 0x000000FF;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 90) buf[2] = (secs & 0x0000FF00) >> 8;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 91) buf[3] = (secs & 0x00FF0000) >> 16;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 92) buf[4] = (secs & 0xFF000000) >> 24;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 93) buf[5] = 0; /* set control reg to enable counting */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 94)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 95) xfer = i2c_master_send(client, buf, 6);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 96) if (xfer != 6) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 97) dev_err(&client->dev, "%s: send: %d\n", __func__, xfer);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 98) return -EIO;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 99) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 100)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 101) return 0;
^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) static const struct rtc_class_ops ds1672_rtc_ops = {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 105) .read_time = ds1672_read_time,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 106) .set_time = ds1672_set_time,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 107) };
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 108)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 109) static int ds1672_probe(struct i2c_client *client,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 110) const struct i2c_device_id *id)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 111) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 112) int err = 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 113) struct rtc_device *rtc;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 114)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 115) dev_dbg(&client->dev, "%s\n", __func__);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 116)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 117) if (!i2c_check_functionality(client->adapter, I2C_FUNC_I2C))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 118) return -ENODEV;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 119)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 120) rtc = devm_rtc_allocate_device(&client->dev);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 121) if (IS_ERR(rtc))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 122) return PTR_ERR(rtc);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 123)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 124) rtc->ops = &ds1672_rtc_ops;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 125) rtc->range_max = U32_MAX;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 126)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 127) err = rtc_register_device(rtc);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 128) if (err)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 129) return err;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 130)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 131) i2c_set_clientdata(client, rtc);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 132)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 133) return 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 134) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 135)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 136) static const struct i2c_device_id ds1672_id[] = {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 137) { "ds1672", 0 },
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 138) { }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 139) };
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 140) MODULE_DEVICE_TABLE(i2c, ds1672_id);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 141)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 142) static const struct of_device_id ds1672_of_match[] = {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 143) { .compatible = "dallas,ds1672" },
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 144) { }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 145) };
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 146) MODULE_DEVICE_TABLE(of, ds1672_of_match);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 147)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 148) static struct i2c_driver ds1672_driver = {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 149) .driver = {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 150) .name = "rtc-ds1672",
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 151) .of_match_table = of_match_ptr(ds1672_of_match),
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 152) },
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 153) .probe = &ds1672_probe,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 154) .id_table = ds1672_id,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 155) };
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 156)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 157) module_i2c_driver(ds1672_driver);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 158)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 159) MODULE_AUTHOR("Alessandro Zummo <a.zummo@towertech.it>");
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 160) MODULE_DESCRIPTION("Dallas/Maxim DS1672 timekeeper driver");
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 161) MODULE_LICENSE("GPL");
Orange Pi5 kernel
Deprecated Linux kernel 5.10.110 for OrangePi 5/5B/5+ boards
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