1 // SPDX-License-Identifier: GPL-2.0-only
2 /* drivers/rtc/rtc-rx4581.c
6  * Based on:
7  * drivers/rtc/rtc-max6902.c
12  * Driver for MAX6902 spi RTC
14  * and based on:
15  * drivers/rtc/rtc-rx8581.c
22  * Based on: rtc-pcf8563.c (An I2C driver for the Philips PCF8563 RTC)
23  * Copyright 2005-06 Tower Technologies
31 #include <linux/spi/spi.h>
69 	struct spi_device *spi = to_spi_device(dev);  in rx4581_set_reg()  local
76 	return spi_write_then_read(spi, buf, 2, NULL, 0);  in rx4581_set_reg()
82 	struct spi_device *spi = to_spi_device(dev);  in rx4581_get_reg()  local
87 	return spi_write_then_read(spi, data, 1, data, 1);  in rx4581_get_reg()
92  * rtc_time -- month 0-11, hour 0-23, yr = calendar year-epoch.
96 	struct spi_device *spi = to_spi_device(dev);  in rx4581_get_datetime()  local
102 	 * time and date then re-read the "update flag". If the update flag  in rx4581_get_datetime()
109 		return -EIO;  in rx4581_get_datetime()
120 				return -EIO;  in rx4581_get_datetime()
126 		err = spi_write_then_read(spi, date, 1, date, 7);  in rx4581_get_datetime()
129 			return -EIO;  in rx4581_get_datetime()
136 			return -EIO;  in rx4581_get_datetime()
150 	tm->tm_sec = bcd2bin(date[RX4581_REG_SC] & 0x7F);  in rx4581_get_datetime()
151 	tm->tm_min = bcd2bin(date[RX4581_REG_MN] & 0x7F);  in rx4581_get_datetime()
152 	tm->tm_hour = bcd2bin(date[RX4581_REG_HR] & 0x3F); /* rtc hr 0-23 */  in rx4581_get_datetime()
153 	tm->tm_wday = ilog2(date[RX4581_REG_DW] & 0x7F);  in rx4581_get_datetime()
154 	tm->tm_mday = bcd2bin(date[RX4581_REG_DM] & 0x3F);  in rx4581_get_datetime()
155 	tm->tm_mon = bcd2bin(date[RX4581_REG_MO] & 0x1F) - 1; /* rtc mn 1-12 */  in rx4581_get_datetime()
156 	tm->tm_year = bcd2bin(date[RX4581_REG_YR]);  in rx4581_get_datetime()
157 	if (tm->tm_year < 70)  in rx4581_get_datetime()
158 		tm->tm_year += 100;	/* assume we are in 1970...2069 */  in rx4581_get_datetime()
164 		tm->tm_sec, tm->tm_min, tm->tm_hour,  in rx4581_get_datetime()
165 		tm->tm_mday, tm->tm_mon, tm->tm_year, tm->tm_wday);  in rx4581_get_datetime()
172 	struct spi_device *spi = to_spi_device(dev);  in rx4581_set_datetime()  local
179 		tm->tm_sec, tm->tm_min, tm->tm_hour,  in rx4581_set_datetime()
180 		tm->tm_mday, tm->tm_mon, tm->tm_year, tm->tm_wday);  in rx4581_set_datetime()
184 	buf[RX4581_REG_SC+1] = bin2bcd(tm->tm_sec);  in rx4581_set_datetime()
185 	buf[RX4581_REG_MN+1] = bin2bcd(tm->tm_min);  in rx4581_set_datetime()
186 	buf[RX4581_REG_HR+1] = bin2bcd(tm->tm_hour);  in rx4581_set_datetime()
188 	buf[RX4581_REG_DM+1] = bin2bcd(tm->tm_mday);  in rx4581_set_datetime()
190 	/* month, 1 - 12 */  in rx4581_set_datetime()
191 	buf[RX4581_REG_MO+1] = bin2bcd(tm->tm_mon + 1);  in rx4581_set_datetime()
194 	buf[RX4581_REG_YR+1] = bin2bcd(tm->tm_year % 100);  in rx4581_set_datetime()
195 	buf[RX4581_REG_DW+1] = (0x1 << tm->tm_wday);  in rx4581_set_datetime()
201 		return -EIO;  in rx4581_set_datetime()
208 		return -EIO;  in rx4581_set_datetime()
212 	err = spi_write_then_read(spi, buf, 8, NULL, 0);  in rx4581_set_datetime()
215 		return -EIO;  in rx4581_set_datetime()
222 		return -EIO;  in rx4581_set_datetime()
229 		return -EIO;  in rx4581_set_datetime()
236 		return -EIO;  in rx4581_set_datetime()
243 		return -EIO;  in rx4581_set_datetime()
254 static int rx4581_probe(struct spi_device *spi)  in rx4581_probe()  argument
260 	res = rx4581_get_reg(&spi->dev, RX4581_REG_SC, &tmp);  in rx4581_probe()
264 	rtc = devm_rtc_device_register(&spi->dev, "rx4581",  in rx4581_probe()
269 	spi_set_drvdata(spi, rtc);  in rx4581_probe()
277 MODULE_DEVICE_TABLE(spi, rx4581_id);
281 		.name	= "rtc-rx4581",
289 MODULE_DESCRIPTION("rx4581 spi RTC driver");
292 MODULE_ALIAS("spi:rtc-rx4581");