// SPDX-License-Identifier: GPL-2.0-only/* rtc-bq4802.c: TI BQ4802 RTC driver. * * Copyright (C) 2008 David S. Miller <davem@davemloft.net> */ #include <linux/kernel.h>#include <linux/module.h>#include <linux/init.h>#include <linux/io.h>#include <linux/platform_device.h>#include <linux/rtc.h>#include <linux/bcd.h>#include <linux/slab.h> MODULE_AUTHOR("David S. Miller <davem@davemloft.net>");MODULE_DESCRIPTION("TI BQ4802 RTC driver");MODULE_LICENSE("GPL"); struct bq4802 {	void __iomem		*regs;	unsigned long		ioport;	struct rtc_device	*rtc;	spinlock_t		lock;	struct resource		*r;	u8 (*read)(struct bq4802 *, int);	void (*write)(struct bq4802 *, int, u8);}; static u8 bq4802_read_io(struct bq4802 *p, int off){	return inb(p->ioport + off);} static void bq4802_write_io(struct bq4802 *p, int off, u8 val){	outb(val, p->ioport + off);} static u8 bq4802_read_mem(struct bq4802 *p, int off){	return readb(p->regs + off);} static void bq4802_write_mem(struct bq4802 *p, int off, u8 val){	writeb(val, p->regs + off);} static int bq4802_read_time(struct device *dev, struct rtc_time *tm){	struct bq4802 *p = dev_get_drvdata(dev);	unsigned long flags;	unsigned int century;	u8 val; 	spin_lock_irqsave(&p->lock, flags); 	val = p->read(p, 0x0e);	p->write(p, 0xe, val | 0x08); 	tm->tm_sec = p->read(p, 0x00);	tm->tm_min = p->read(p, 0x02);	tm->tm_hour = p->read(p, 0x04);	tm->tm_mday = p->read(p, 0x06);	tm->tm_mon = p->read(p, 0x09);	tm->tm_year = p->read(p, 0x0a);	tm->tm_wday = p->read(p, 0x08);	century = p->read(p, 0x0f); 	p->write(p, 0x0e, val); 	spin_unlock_irqrestore(&p->lock, flags); 	tm->tm_sec = bcd2bin(tm->tm_sec);	tm->tm_min = bcd2bin(tm->tm_min);	tm->tm_hour = bcd2bin(tm->tm_hour);	tm->tm_mday = bcd2bin(tm->tm_mday);	tm->tm_mon = bcd2bin(tm->tm_mon);	tm->tm_year = bcd2bin(tm->tm_year);	tm->tm_wday = bcd2bin(tm->tm_wday);	century = bcd2bin(century); 	tm->tm_year += (century * 100);	tm->tm_year -= 1900; 	tm->tm_mon--; 	return 0;} static int bq4802_set_time(struct device *dev, struct rtc_time *tm){	struct bq4802 *p = dev_get_drvdata(dev);	u8 sec, min, hrs, day, mon, yrs, century, val;	unsigned long flags;	unsigned int year; 	year = tm->tm_year + 1900;	century = year / 100;	yrs = year % 100; 	mon = tm->tm_mon + 1;   /* tm_mon starts at zero */	day = tm->tm_mday;	hrs = tm->tm_hour;	min = tm->tm_min;	sec = tm->tm_sec; 	sec = bin2bcd(sec);	min = bin2bcd(min);	hrs = bin2bcd(hrs);	day = bin2bcd(day);	mon = bin2bcd(mon);	yrs = bin2bcd(yrs);	century = bin2bcd(century); 	spin_lock_irqsave(&p->lock, flags); 	val = p->read(p, 0x0e);	p->write(p, 0x0e, val | 0x08); 	p->write(p, 0x00, sec);	p->write(p, 0x02, min);	p->write(p, 0x04, hrs);	p->write(p, 0x06, day);	p->write(p, 0x09, mon);	p->write(p, 0x0a, yrs);	p->write(p, 0x0f, century); 	p->write(p, 0x0e, val); 	spin_unlock_irqrestore(&p->lock, flags); 	return 0;} static const struct rtc_class_ops bq4802_ops = {	.read_time	= bq4802_read_time,	.set_time	= bq4802_set_time,}; static int bq4802_probe(struct platform_device *pdev){	struct bq4802 *p = devm_kzalloc(&pdev->dev, sizeof(*p), GFP_KERNEL);	int err = -ENOMEM; 	if (!p)		goto out; 	spin_lock_init(&p->lock); 	p->r = platform_get_resource(pdev, IORESOURCE_MEM, 0);	if (!p->r) {		p->r = platform_get_resource(pdev, IORESOURCE_IO, 0);		err = -EINVAL;		if (!p->r)			goto out;	}	if (p->r->flags & IORESOURCE_IO) {		p->ioport = p->r->start;		p->read = bq4802_read_io;		p->write = bq4802_write_io;	} else if (p->r->flags & IORESOURCE_MEM) {		p->regs = devm_ioremap(&pdev->dev, p->r->start,					resource_size(p->r));		if (!p->regs){			err = -ENOMEM;			goto out;		}		p->read = bq4802_read_mem;		p->write = bq4802_write_mem;	} else {		err = -EINVAL;		goto out;	} 	platform_set_drvdata(pdev, p); 	p->rtc = devm_rtc_device_register(&pdev->dev, "bq4802",					&bq4802_ops, THIS_MODULE);	if (IS_ERR(p->rtc)) {		err = PTR_ERR(p->rtc);		goto out;	} 	err = 0;out:	return err; } /* work with hotplug and coldplug */MODULE_ALIAS("platform:rtc-bq4802"); static struct platform_driver bq4802_driver = {	.driver		= {		.name	= "rtc-bq4802",	},	.probe		= bq4802_probe,}; module_platform_driver(bq4802_driver);