Initial import

1 files changed, 516 insertions, 0 deletions

diff --git a/drivers/rtc/rtc-m48t59.c b/drivers/rtc/rtc-m48t59.c
new file mode 100644
index 000000000..90abb5bd5
--- /dev/null
+++ b/drivers/rtc/rtc-m48t59.c
@@ -0,0 +1,516 @@
+/*
+ * ST M48T59 RTC driver
+ *
+ * Copyright (c) 2007 Wind River Systems, Inc.
+ *
+ * Author: Mark Zhan <rongkai.zhan@windriver.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/io.h>
+#include <linux/device.h>
+#include <linux/platform_device.h>
+#include <linux/rtc.h>
+#include <linux/rtc/m48t59.h>
+#include <linux/bcd.h>
+#include <linux/slab.h>
+
+#ifndef NO_IRQ
+#define NO_IRQ	(-1)
+#endif
+
+#define M48T59_READ(reg) (pdata->read_byte(dev, pdata->offset + reg))
+#define M48T59_WRITE(val, reg) \
+	(pdata->write_byte(dev, pdata->offset + reg, val))
+
+#define M48T59_SET_BITS(mask, reg)	\
+	M48T59_WRITE((M48T59_READ(reg) | (mask)), (reg))
+#define M48T59_CLEAR_BITS(mask, reg)	\
+	M48T59_WRITE((M48T59_READ(reg) & ~(mask)), (reg))
+
+struct m48t59_private {
+	void __iomem *ioaddr;
+	int irq;
+	struct rtc_device *rtc;
+	spinlock_t lock; /* serialize the NVRAM and RTC access */
+};
+
+/*
+ * This is the generic access method when the chip is memory-mapped
+ */
+static void
+m48t59_mem_writeb(struct device *dev, u32 ofs, u8 val)
+{
+	struct platform_device *pdev = to_platform_device(dev);
+	struct m48t59_private *m48t59 = platform_get_drvdata(pdev);
+
+	writeb(val, m48t59->ioaddr+ofs);
+}
+
+static u8
+m48t59_mem_readb(struct device *dev, u32 ofs)
+{
+	struct platform_device *pdev = to_platform_device(dev);
+	struct m48t59_private *m48t59 = platform_get_drvdata(pdev);
+
+	return readb(m48t59->ioaddr+ofs);
+}
+
+/*
+ * NOTE: M48T59 only uses BCD mode
+ */
+static int m48t59_rtc_read_time(struct device *dev, struct rtc_time *tm)
+{
+	struct platform_device *pdev = to_platform_device(dev);
+	struct m48t59_plat_data *pdata = dev_get_platdata(&pdev->dev);
+	struct m48t59_private *m48t59 = platform_get_drvdata(pdev);
+	unsigned long flags;
+	u8 val;
+
+	spin_lock_irqsave(&m48t59->lock, flags);
+	/* Issue the READ command */
+	M48T59_SET_BITS(M48T59_CNTL_READ, M48T59_CNTL);
+
+	tm->tm_year	= bcd2bin(M48T59_READ(M48T59_YEAR));
+	/* tm_mon is 0-11 */
+	tm->tm_mon	= bcd2bin(M48T59_READ(M48T59_MONTH)) - 1;
+	tm->tm_mday	= bcd2bin(M48T59_READ(M48T59_MDAY));
+
+	val = M48T59_READ(M48T59_WDAY);
+	if ((pdata->type == M48T59RTC_TYPE_M48T59) &&
+	    (val & M48T59_WDAY_CEB) && (val & M48T59_WDAY_CB)) {
+		dev_dbg(dev, "Century bit is enabled\n");
+		tm->tm_year += 100;	/* one century */
+	}
+#ifdef CONFIG_SPARC
+	/* Sun SPARC machines count years since 1968 */
+	tm->tm_year += 68;
+#endif
+
+	tm->tm_wday	= bcd2bin(val & 0x07);
+	tm->tm_hour	= bcd2bin(M48T59_READ(M48T59_HOUR) & 0x3F);
+	tm->tm_min	= bcd2bin(M48T59_READ(M48T59_MIN) & 0x7F);
+	tm->tm_sec	= bcd2bin(M48T59_READ(M48T59_SEC) & 0x7F);
+
+	/* Clear the READ bit */
+	M48T59_CLEAR_BITS(M48T59_CNTL_READ, M48T59_CNTL);
+	spin_unlock_irqrestore(&m48t59->lock, flags);
+
+	dev_dbg(dev, "RTC read time %04d-%02d-%02d %02d/%02d/%02d\n",
+		tm->tm_year + 1900, tm->tm_mon, tm->tm_mday,
+		tm->tm_hour, tm->tm_min, tm->tm_sec);
+	return rtc_valid_tm(tm);
+}
+
+static int m48t59_rtc_set_time(struct device *dev, struct rtc_time *tm)
+{
+	struct platform_device *pdev = to_platform_device(dev);
+	struct m48t59_plat_data *pdata = dev_get_platdata(&pdev->dev);
+	struct m48t59_private *m48t59 = platform_get_drvdata(pdev);
+	unsigned long flags;
+	u8 val = 0;
+	int year = tm->tm_year;
+
+#ifdef CONFIG_SPARC
+	/* Sun SPARC machines count years since 1968 */
+	year -= 68;
+#endif
+
+	dev_dbg(dev, "RTC set time %04d-%02d-%02d %02d/%02d/%02d\n",
+		year + 1900, tm->tm_mon, tm->tm_mday,
+		tm->tm_hour, tm->tm_min, tm->tm_sec);
+
+	if (year < 0)
+		return -EINVAL;
+
+	spin_lock_irqsave(&m48t59->lock, flags);
+	/* Issue the WRITE command */
+	M48T59_SET_BITS(M48T59_CNTL_WRITE, M48T59_CNTL);
+
+	M48T59_WRITE((bin2bcd(tm->tm_sec) & 0x7F), M48T59_SEC);
+	M48T59_WRITE((bin2bcd(tm->tm_min) & 0x7F), M48T59_MIN);
+	M48T59_WRITE((bin2bcd(tm->tm_hour) & 0x3F), M48T59_HOUR);
+	M48T59_WRITE((bin2bcd(tm->tm_mday) & 0x3F), M48T59_MDAY);
+	/* tm_mon is 0-11 */
+	M48T59_WRITE((bin2bcd(tm->tm_mon + 1) & 0x1F), M48T59_MONTH);
+	M48T59_WRITE(bin2bcd(year % 100), M48T59_YEAR);
+
+	if (pdata->type == M48T59RTC_TYPE_M48T59 && (year / 100))
+		val = (M48T59_WDAY_CEB | M48T59_WDAY_CB);
+	val |= (bin2bcd(tm->tm_wday) & 0x07);
+	M48T59_WRITE(val, M48T59_WDAY);
+
+	/* Clear the WRITE bit */
+	M48T59_CLEAR_BITS(M48T59_CNTL_WRITE, M48T59_CNTL);
+	spin_unlock_irqrestore(&m48t59->lock, flags);
+	return 0;
+}
+
+/*
+ * Read alarm time and date in RTC
+ */
+static int m48t59_rtc_readalarm(struct device *dev, struct rtc_wkalrm *alrm)
+{
+	struct platform_device *pdev = to_platform_device(dev);
+	struct m48t59_plat_data *pdata = dev_get_platdata(&pdev->dev);
+	struct m48t59_private *m48t59 = platform_get_drvdata(pdev);
+	struct rtc_time *tm = &alrm->time;
+	unsigned long flags;
+	u8 val;
+
+	/* If no irq, we don't support ALARM */
+	if (m48t59->irq == NO_IRQ)
+		return -EIO;
+
+	spin_lock_irqsave(&m48t59->lock, flags);
+	/* Issue the READ command */
+	M48T59_SET_BITS(M48T59_CNTL_READ, M48T59_CNTL);
+
+	tm->tm_year = bcd2bin(M48T59_READ(M48T59_YEAR));
+#ifdef CONFIG_SPARC
+	/* Sun SPARC machines count years since 1968 */
+	tm->tm_year += 68;
+#endif
+	/* tm_mon is 0-11 */
+	tm->tm_mon = bcd2bin(M48T59_READ(M48T59_MONTH)) - 1;
+
+	val = M48T59_READ(M48T59_WDAY);
+	if ((val & M48T59_WDAY_CEB) && (val & M48T59_WDAY_CB))
+		tm->tm_year += 100;	/* one century */
+
+	tm->tm_mday = bcd2bin(M48T59_READ(M48T59_ALARM_DATE));
+	tm->tm_hour = bcd2bin(M48T59_READ(M48T59_ALARM_HOUR));
+	tm->tm_min = bcd2bin(M48T59_READ(M48T59_ALARM_MIN));
+	tm->tm_sec = bcd2bin(M48T59_READ(M48T59_ALARM_SEC));
+
+	/* Clear the READ bit */
+	M48T59_CLEAR_BITS(M48T59_CNTL_READ, M48T59_CNTL);
+	spin_unlock_irqrestore(&m48t59->lock, flags);
+
+	dev_dbg(dev, "RTC read alarm time %04d-%02d-%02d %02d/%02d/%02d\n",
+		tm->tm_year + 1900, tm->tm_mon, tm->tm_mday,
+		tm->tm_hour, tm->tm_min, tm->tm_sec);
+	return rtc_valid_tm(tm);
+}
+
+/*
+ * Set alarm time and date in RTC
+ */
+static int m48t59_rtc_setalarm(struct device *dev, struct rtc_wkalrm *alrm)
+{
+	struct platform_device *pdev = to_platform_device(dev);
+	struct m48t59_plat_data *pdata = dev_get_platdata(&pdev->dev);
+	struct m48t59_private *m48t59 = platform_get_drvdata(pdev);
+	struct rtc_time *tm = &alrm->time;
+	u8 mday, hour, min, sec;
+	unsigned long flags;
+	int year = tm->tm_year;
+
+#ifdef CONFIG_SPARC
+	/* Sun SPARC machines count years since 1968 */
+	year -= 68;
+#endif
+
+	/* If no irq, we don't support ALARM */
+	if (m48t59->irq == NO_IRQ)
+		return -EIO;
+
+	if (year < 0)
+		return -EINVAL;
+
+	/*
+	 * 0xff means "always match"
+	 */
+	mday = tm->tm_mday;
+	mday = (mday >= 1 && mday <= 31) ? bin2bcd(mday) : 0xff;
+	if (mday == 0xff)
+		mday = M48T59_READ(M48T59_MDAY);
+
+	hour = tm->tm_hour;
+	hour = (hour < 24) ? bin2bcd(hour) : 0x00;
+
+	min = tm->tm_min;
+	min = (min < 60) ? bin2bcd(min) : 0x00;
+
+	sec = tm->tm_sec;
+	sec = (sec < 60) ? bin2bcd(sec) : 0x00;
+
+	spin_lock_irqsave(&m48t59->lock, flags);
+	/* Issue the WRITE command */
+	M48T59_SET_BITS(M48T59_CNTL_WRITE, M48T59_CNTL);
+
+	M48T59_WRITE(mday, M48T59_ALARM_DATE);
+	M48T59_WRITE(hour, M48T59_ALARM_HOUR);
+	M48T59_WRITE(min, M48T59_ALARM_MIN);
+	M48T59_WRITE(sec, M48T59_ALARM_SEC);
+
+	/* Clear the WRITE bit */
+	M48T59_CLEAR_BITS(M48T59_CNTL_WRITE, M48T59_CNTL);
+	spin_unlock_irqrestore(&m48t59->lock, flags);
+
+	dev_dbg(dev, "RTC set alarm time %04d-%02d-%02d %02d/%02d/%02d\n",
+		year + 1900, tm->tm_mon, tm->tm_mday,
+		tm->tm_hour, tm->tm_min, tm->tm_sec);
+	return 0;
+}
+
+/*
+ * Handle commands from user-space
+ */
+static int m48t59_rtc_alarm_irq_enable(struct device *dev, unsigned int enabled)
+{
+	struct platform_device *pdev = to_platform_device(dev);
+	struct m48t59_plat_data *pdata = dev_get_platdata(&pdev->dev);
+	struct m48t59_private *m48t59 = platform_get_drvdata(pdev);
+	unsigned long flags;
+
+	spin_lock_irqsave(&m48t59->lock, flags);
+	if (enabled)
+		M48T59_WRITE(M48T59_INTR_AFE, M48T59_INTR);
+	else
+		M48T59_WRITE(0x00, M48T59_INTR);
+	spin_unlock_irqrestore(&m48t59->lock, flags);
+
+	return 0;
+}
+
+static int m48t59_rtc_proc(struct device *dev, struct seq_file *seq)
+{
+	struct platform_device *pdev = to_platform_device(dev);
+	struct m48t59_plat_data *pdata = dev_get_platdata(&pdev->dev);
+	struct m48t59_private *m48t59 = platform_get_drvdata(pdev);
+	unsigned long flags;
+	u8 val;
+
+	spin_lock_irqsave(&m48t59->lock, flags);
+	val = M48T59_READ(M48T59_FLAGS);
+	spin_unlock_irqrestore(&m48t59->lock, flags);
+
+	seq_printf(seq, "battery\t\t: %s\n",
+		 (val & M48T59_FLAGS_BF) ? "low" : "normal");
+	return 0;
+}
+
+/*
+ * IRQ handler for the RTC
+ */
+static irqreturn_t m48t59_rtc_interrupt(int irq, void *dev_id)
+{
+	struct device *dev = (struct device *)dev_id;
+	struct platform_device *pdev = to_platform_device(dev);
+	struct m48t59_plat_data *pdata = dev_get_platdata(&pdev->dev);
+	struct m48t59_private *m48t59 = platform_get_drvdata(pdev);
+	u8 event;
+
+	spin_lock(&m48t59->lock);
+	event = M48T59_READ(M48T59_FLAGS);
+	spin_unlock(&m48t59->lock);
+
+	if (event & M48T59_FLAGS_AF) {
+		rtc_update_irq(m48t59->rtc, 1, (RTC_AF | RTC_IRQF));
+		return IRQ_HANDLED;
+	}
+
+	return IRQ_NONE;
+}
+
+static const struct rtc_class_ops m48t59_rtc_ops = {
+	.read_time	= m48t59_rtc_read_time,
+	.set_time	= m48t59_rtc_set_time,
+	.read_alarm	= m48t59_rtc_readalarm,
+	.set_alarm	= m48t59_rtc_setalarm,
+	.proc		= m48t59_rtc_proc,
+	.alarm_irq_enable = m48t59_rtc_alarm_irq_enable,
+};
+
+static const struct rtc_class_ops m48t02_rtc_ops = {
+	.read_time	= m48t59_rtc_read_time,
+	.set_time	= m48t59_rtc_set_time,
+};
+
+static ssize_t m48t59_nvram_read(struct file *filp, struct kobject *kobj,
+				struct bin_attribute *bin_attr,
+				char *buf, loff_t pos, size_t size)
+{
+	struct device *dev = container_of(kobj, struct device, kobj);
+	struct platform_device *pdev = to_platform_device(dev);
+	struct m48t59_plat_data *pdata = dev_get_platdata(&pdev->dev);
+	struct m48t59_private *m48t59 = platform_get_drvdata(pdev);
+	ssize_t cnt = 0;
+	unsigned long flags;
+
+	for (; size > 0 && pos < pdata->offset; cnt++, size--) {
+		spin_lock_irqsave(&m48t59->lock, flags);
+		*buf++ = M48T59_READ(cnt);
+		spin_unlock_irqrestore(&m48t59->lock, flags);
+	}
+
+	return cnt;
+}
+
+static ssize_t m48t59_nvram_write(struct file *filp, struct kobject *kobj,
+				struct bin_attribute *bin_attr,
+				char *buf, loff_t pos, size_t size)
+{
+	struct device *dev = container_of(kobj, struct device, kobj);
+	struct platform_device *pdev = to_platform_device(dev);
+	struct m48t59_plat_data *pdata = dev_get_platdata(&pdev->dev);
+	struct m48t59_private *m48t59 = platform_get_drvdata(pdev);
+	ssize_t cnt = 0;
+	unsigned long flags;
+
+	for (; size > 0 && pos < pdata->offset; cnt++, size--) {
+		spin_lock_irqsave(&m48t59->lock, flags);
+		M48T59_WRITE(*buf++, cnt);
+		spin_unlock_irqrestore(&m48t59->lock, flags);
+	}
+
+	return cnt;
+}
+
+static struct bin_attribute m48t59_nvram_attr = {
+	.attr = {
+		.name = "nvram",
+		.mode = S_IRUGO | S_IWUSR,
+	},
+	.read = m48t59_nvram_read,
+	.write = m48t59_nvram_write,
+};
+
+static int m48t59_rtc_probe(struct platform_device *pdev)
+{
+	struct m48t59_plat_data *pdata = dev_get_platdata(&pdev->dev);
+	struct m48t59_private *m48t59 = NULL;
+	struct resource *res;
+	int ret = -ENOMEM;
+	char *name;
+	const struct rtc_class_ops *ops;
+
+	/* This chip could be memory-mapped or I/O-mapped */
+	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	if (!res) {
+		res = platform_get_resource(pdev, IORESOURCE_IO, 0);
+		if (!res)
+			return -EINVAL;
+	}
+
+	if (res->flags & IORESOURCE_IO) {
+		/* If we are I/O-mapped, the platform should provide
+		 * the operations accessing chip registers.
+		 */
+		if (!pdata || !pdata->write_byte || !pdata->read_byte)
+			return -EINVAL;
+	} else if (res->flags & IORESOURCE_MEM) {
+		/* we are memory-mapped */
+		if (!pdata) {
+			pdata = devm_kzalloc(&pdev->dev, sizeof(*pdata),
+						GFP_KERNEL);
+			if (!pdata)
+				return -ENOMEM;
+			/* Ensure we only kmalloc platform data once */
+			pdev->dev.platform_data = pdata;
+		}
+		if (!pdata->type)
+			pdata->type = M48T59RTC_TYPE_M48T59;
+
+		/* Try to use the generic memory read/write ops */
+		if (!pdata->write_byte)
+			pdata->write_byte = m48t59_mem_writeb;
+		if (!pdata->read_byte)
+			pdata->read_byte = m48t59_mem_readb;
+	}
+
+	m48t59 = devm_kzalloc(&pdev->dev, sizeof(*m48t59), GFP_KERNEL);
+	if (!m48t59)
+		return -ENOMEM;
+
+	m48t59->ioaddr = pdata->ioaddr;
+
+	if (!m48t59->ioaddr) {
+		/* ioaddr not mapped externally */
+		m48t59->ioaddr = devm_ioremap(&pdev->dev, res->start,
+						resource_size(res));
+		if (!m48t59->ioaddr)
+			return ret;
+	}
+
+	/* Try to get irq number. We also can work in
+	 * the mode without IRQ.
+	 */
+	m48t59->irq = platform_get_irq(pdev, 0);
+	if (m48t59->irq <= 0)
+		m48t59->irq = NO_IRQ;
+
+	if (m48t59->irq != NO_IRQ) {
+		ret = devm_request_irq(&pdev->dev, m48t59->irq,
+				m48t59_rtc_interrupt, IRQF_SHARED,
+				"rtc-m48t59", &pdev->dev);
+		if (ret)
+			return ret;
+	}
+	switch (pdata->type) {
+	case M48T59RTC_TYPE_M48T59:
+		name = "m48t59";
+		ops = &m48t59_rtc_ops;
+		pdata->offset = 0x1ff0;
+		break;
+	case M48T59RTC_TYPE_M48T02:
+		name = "m48t02";
+		ops = &m48t02_rtc_ops;
+		pdata->offset = 0x7f0;
+		break;
+	case M48T59RTC_TYPE_M48T08:
+		name = "m48t08";
+		ops = &m48t02_rtc_ops;
+		pdata->offset = 0x1ff0;
+		break;
+	default:
+		dev_err(&pdev->dev, "Unknown RTC type\n");
+		return -ENODEV;
+	}
+
+	spin_lock_init(&m48t59->lock);
+	platform_set_drvdata(pdev, m48t59);
+
+	m48t59->rtc = devm_rtc_device_register(&pdev->dev, name, ops,
+						THIS_MODULE);
+	if (IS_ERR(m48t59->rtc))
+		return PTR_ERR(m48t59->rtc);
+
+	m48t59_nvram_attr.size = pdata->offset;
+
+	ret = sysfs_create_bin_file(&pdev->dev.kobj, &m48t59_nvram_attr);
+	if (ret)
+		return ret;
+
+	return 0;
+}
+
+static int m48t59_rtc_remove(struct platform_device *pdev)
+{
+	sysfs_remove_bin_file(&pdev->dev.kobj, &m48t59_nvram_attr);
+	return 0;
+}
+
+/* work with hotplug and coldplug */
+MODULE_ALIAS("platform:rtc-m48t59");
+
+static struct platform_driver m48t59_rtc_driver = {
+	.driver		= {
+		.name	= "rtc-m48t59",
+	},
+	.probe		= m48t59_rtc_probe,
+	.remove		= m48t59_rtc_remove,
+};
+
+module_platform_driver(m48t59_rtc_driver);
+
+MODULE_AUTHOR("Mark Zhan <rongkai.zhan@windriver.com>");
+MODULE_DESCRIPTION("M48T59/M48T02/M48T08 RTC driver");
+MODULE_LICENSE("GPL");