^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1) // SPDX-License-Identifier: GPL-2.0-or-later
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 2) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 3) * Driver for the SGS-Thomson M48T35 Timekeeper RAM chip
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 4) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 5) * Copyright (C) 2000 Silicon Graphics, Inc.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 6) * Written by Ulf Carlsson (ulfc@engr.sgi.com)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 7) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 8) * Copyright (C) 2008 Thomas Bogendoerfer
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 9) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 10) * Based on code written by Paul Gortmaker.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 11) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 12)
^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/rtc.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 15) #include <linux/slab.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 16) #include <linux/platform_device.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 17) #include <linux/bcd.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 18) #include <linux/io.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 19) #include <linux/err.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 20)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 21) struct m48t35_rtc {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 22) u8 pad[0x7ff8]; /* starts at 0x7ff8 */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 23) #ifdef CONFIG_SGI_IP27
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 24) u8 hour;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 25) u8 min;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 26) u8 sec;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 27) u8 control;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 28) u8 year;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 29) u8 month;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 30) u8 date;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 31) u8 day;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 32) #else
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 33) u8 control;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 34) u8 sec;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 35) u8 min;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 36) u8 hour;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 37) u8 day;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 38) u8 date;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 39) u8 month;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 40) u8 year;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 41) #endif
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 42) };
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 43)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 44) #define M48T35_RTC_SET 0x80
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 45) #define M48T35_RTC_READ 0x40
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 46)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 47) struct m48t35_priv {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 48) struct rtc_device *rtc;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 49) struct m48t35_rtc __iomem *reg;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 50) size_t size;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 51) unsigned long baseaddr;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 52) spinlock_t lock;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 53) };
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 54)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 55) static int m48t35_read_time(struct device *dev, struct rtc_time *tm)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 56) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 57) struct m48t35_priv *priv = dev_get_drvdata(dev);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 58) u8 control;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 59)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 60) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 61) * Only the values that we read from the RTC are set. We leave
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 62) * tm_wday, tm_yday and tm_isdst untouched. Even though the
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 63) * RTC has RTC_DAY_OF_WEEK, we ignore it, as it is only updated
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 64) * by the RTC when initially set to a non-zero value.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 65) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 66) spin_lock_irq(&priv->lock);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 67) control = readb(&priv->reg->control);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 68) writeb(control | M48T35_RTC_READ, &priv->reg->control);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 69) tm->tm_sec = readb(&priv->reg->sec);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 70) tm->tm_min = readb(&priv->reg->min);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 71) tm->tm_hour = readb(&priv->reg->hour);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 72) tm->tm_mday = readb(&priv->reg->date);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 73) tm->tm_mon = readb(&priv->reg->month);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 74) tm->tm_year = readb(&priv->reg->year);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 75) writeb(control, &priv->reg->control);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 76) spin_unlock_irq(&priv->lock);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 77)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 78) tm->tm_sec = bcd2bin(tm->tm_sec);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 79) tm->tm_min = bcd2bin(tm->tm_min);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 80) tm->tm_hour = bcd2bin(tm->tm_hour);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 81) tm->tm_mday = bcd2bin(tm->tm_mday);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 82) tm->tm_mon = bcd2bin(tm->tm_mon);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 83) tm->tm_year = bcd2bin(tm->tm_year);
^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) * Account for differences between how the RTC uses the values
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 87) * and how they are defined in a struct rtc_time;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 88) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 89) tm->tm_year += 70;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 90) if (tm->tm_year <= 69)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 91) tm->tm_year += 100;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 92)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 93) tm->tm_mon--;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 94) return 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 95) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 96)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 97) static int m48t35_set_time(struct device *dev, struct rtc_time *tm)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 98) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 99) struct m48t35_priv *priv = dev_get_drvdata(dev);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 100) unsigned char mon, day, hrs, min, sec;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 101) unsigned int yrs;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 102) u8 control;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 103)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 104) yrs = tm->tm_year + 1900;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 105) mon = tm->tm_mon + 1; /* tm_mon starts at zero */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 106) day = tm->tm_mday;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 107) hrs = tm->tm_hour;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 108) min = tm->tm_min;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 109) sec = tm->tm_sec;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 110)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 111) if (yrs < 1970)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 112) return -EINVAL;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 113)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 114) yrs -= 1970;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 115) if (yrs > 255) /* They are unsigned */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 116) return -EINVAL;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 117)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 118) if (yrs > 169)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 119) return -EINVAL;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 120)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 121) if (yrs >= 100)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 122) yrs -= 100;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 123)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 124) sec = bin2bcd(sec);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 125) min = bin2bcd(min);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 126) hrs = bin2bcd(hrs);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 127) day = bin2bcd(day);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 128) mon = bin2bcd(mon);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 129) yrs = bin2bcd(yrs);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 130)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 131) spin_lock_irq(&priv->lock);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 132) control = readb(&priv->reg->control);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 133) writeb(control | M48T35_RTC_SET, &priv->reg->control);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 134) writeb(yrs, &priv->reg->year);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 135) writeb(mon, &priv->reg->month);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 136) writeb(day, &priv->reg->date);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 137) writeb(hrs, &priv->reg->hour);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 138) writeb(min, &priv->reg->min);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 139) writeb(sec, &priv->reg->sec);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 140) writeb(control, &priv->reg->control);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 141) spin_unlock_irq(&priv->lock);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 142) return 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 143) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 144)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 145) static const struct rtc_class_ops m48t35_ops = {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 146) .read_time = m48t35_read_time,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 147) .set_time = m48t35_set_time,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 148) };
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 149)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 150) static int m48t35_probe(struct platform_device *pdev)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 151) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 152) struct resource *res;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 153) struct m48t35_priv *priv;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 154)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 155) res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 156) if (!res)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 157) return -ENODEV;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 158) priv = devm_kzalloc(&pdev->dev, sizeof(struct m48t35_priv), GFP_KERNEL);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 159) if (!priv)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 160) return -ENOMEM;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 161)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 162) priv->size = resource_size(res);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 163) if (!devm_request_mem_region(&pdev->dev, res->start, priv->size,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 164) pdev->name))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 165) return -EBUSY;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 166)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 167) priv->baseaddr = res->start;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 168) priv->reg = devm_ioremap(&pdev->dev, priv->baseaddr, priv->size);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 169) if (!priv->reg)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 170) return -ENOMEM;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 171)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 172) spin_lock_init(&priv->lock);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 173)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 174) platform_set_drvdata(pdev, priv);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 175)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 176) priv->rtc = devm_rtc_device_register(&pdev->dev, "m48t35",
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 177) &m48t35_ops, THIS_MODULE);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 178) return PTR_ERR_OR_ZERO(priv->rtc);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 179) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 180)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 181) static struct platform_driver m48t35_platform_driver = {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 182) .driver = {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 183) .name = "rtc-m48t35",
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 184) },
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 185) .probe = m48t35_probe,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 186) };
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 187)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 188) module_platform_driver(m48t35_platform_driver);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 189)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 190) MODULE_AUTHOR("Thomas Bogendoerfer <tsbogend@alpha.franken.de>");
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 191) MODULE_DESCRIPTION("M48T35 RTC driver");
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 192) MODULE_LICENSE("GPL");
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 193) MODULE_ALIAS("platform:rtc-m48t35");
Orange Pi5 kernel
Deprecated Linux kernel 5.10.110 for OrangePi 5/5B/5+ boards
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