RTC: add rtc-rs5c313 driver

Add an RTC driver for Ricoh RS5C313 RTC chip.

[akpm@linux-foundation.org: Zillions of coding-style fixes]
[akpm@linux-foundation.org: build fixes]
Signed-off-by: Nobuhiro Iwamatsu <iwamatsu@nigauri.org>
Cc: Alessandro Zummo <a.zummo@towertech.it>
Cc: David Brownell <david-b@pacbell.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

3 files changed, 412 insertions, 0 deletions

diff --git a/drivers/rtc/Kconfig b/drivers/rtc/Kconfig
index ef1eae98ba44..372d74963dd4 100644
--- a/drivers/rtc/Kconfig
+++ b/drivers/rtc/Kconfig
@@ -364,4 +364,10 @@ config RTC_DRV_BFIN
 	  This driver can also be built as a module. If so, the module
 	  will be called rtc-bfin.
 
+config RTC_DRV_RS5C313
+	tristate "Ricoh RS5C313"
+	depends on RTC_CLASS && BROKEN
+	help
+	  If you say yes here you get support for the Ricoh RS5C313 RTC chips.
+
 endmenu
diff --git a/drivers/rtc/Makefile b/drivers/rtc/Makefile
index 9218cf28d6ed..cad027d36447 100644
--- a/drivers/rtc/Makefile
+++ b/drivers/rtc/Makefile
@@ -30,6 +30,7 @@ obj-$(CONFIG_RTC_DRV_S3C)	+= rtc-s3c.o
 obj-$(CONFIG_RTC_DRV_RS5C348)	+= rtc-rs5c348.o
 obj-$(CONFIG_RTC_DRV_M48T86)	+= rtc-m48t86.o
 obj-$(CONFIG_RTC_DRV_DS1553)	+= rtc-ds1553.o
+obj-$(CONFIG_RTC_DRV_RS5C313)	+= rtc-rs5c313.o
 obj-$(CONFIG_RTC_DRV_EP93XX)	+= rtc-ep93xx.o
 obj-$(CONFIG_RTC_DRV_SA1100)	+= rtc-sa1100.o
 obj-$(CONFIG_RTC_DRV_VR41XX)	+= rtc-vr41xx.o
diff --git a/drivers/rtc/rtc-rs5c313.c b/drivers/rtc/rtc-rs5c313.c
new file mode 100644
index 000000000000..9d6de371495b
--- /dev/null
+++ b/drivers/rtc/rtc-rs5c313.c
@@ -0,0 +1,405 @@
+/*
+ * Ricoh RS5C313 RTC device/driver
+ *  Copyright (C) 2007 Nobuhiro Iwamatsu
+ *
+ *  2005-09-19 modifed by kogiidena
+ *
+ * Based on the old drivers/char/rs5c313_rtc.c  by:
+ *  Copyright (C) 2000 Philipp Rumpf <prumpf@tux.org>
+ *  Copyright (C) 1999 Tetsuya Okada & Niibe Yutaka
+ *
+ * Based on code written by Paul Gortmaker.
+ *  Copyright (C) 1996 Paul Gortmaker
+ *
+ * This file is subject to the terms and conditions of the GNU General Public
+ * License.  See the file "COPYING" in the main directory of this archive
+ * for more details.
+ *
+ * Based on other minimal char device drivers, like Alan's
+ * watchdog, Ted's random, etc. etc.
+ *
+ *	1.07	Paul Gortmaker.
+ *	1.08	Miquel van Smoorenburg: disallow certain things on the
+ *		DEC Alpha as the CMOS clock is also used for other things.
+ *	1.09	Nikita Schmidt: epoch support and some Alpha cleanup.
+ *	1.09a	Pete Zaitcev: Sun SPARC
+ *	1.09b	Jeff Garzik: Modularize, init cleanup
+ *	1.09c	Jeff Garzik: SMP cleanup
+ *	1.10    Paul Barton-Davis: add support for async I/O
+ *	1.10a	Andrea Arcangeli: Alpha updates
+ *	1.10b	Andrew Morton: SMP lock fix
+ *	1.10c	Cesar Barros: SMP locking fixes and cleanup
+ *	1.10d	Paul Gortmaker: delete paranoia check in rtc_exit
+ *	1.10e	Maciej W. Rozycki: Handle DECstation's year weirdness.
+ *      1.11    Takashi Iwai: Kernel access functions
+ *			      rtc_register/rtc_unregister/rtc_control
+ *      1.11a   Daniele Bellucci: Audit create_proc_read_entry in rtc_init
+ *	1.12	Venkatesh Pallipadi: Hooks for emulating rtc on HPET base-timer
+ *		CONFIG_HPET_EMULATE_RTC
+ *	1.13	Nobuhiro Iwamatsu: Updata driver.
+ */
+
+#include <linux/module.h>
+#include <linux/err.h>
+#include <linux/rtc.h>
+#include <linux/platform_device.h>
+#include <linux/bcd.h>
+#include <linux/delay.h>
+#include <asm/io.h>
+
+#define DRV_NAME	"rs5c313"
+#define DRV_VERSION 	"1.13"
+
+#ifdef CONFIG_SH_LANDISK
+/*****************************************************/
+/* LANDISK dependence part of RS5C313                */
+/*****************************************************/
+
+#define SCSMR1		0xFFE00000
+#define SCSCR1		0xFFE00008
+#define SCSMR1_CA	0x80
+#define SCSCR1_CKE	0x03
+#define SCSPTR1		0xFFE0001C
+#define SCSPTR1_EIO	0x80
+#define SCSPTR1_SPB1IO	0x08
+#define SCSPTR1_SPB1DT	0x04
+#define SCSPTR1_SPB0IO	0x02
+#define SCSPTR1_SPB0DT	0x01
+
+#define SDA_OEN		SCSPTR1_SPB1IO
+#define SDA		SCSPTR1_SPB1DT
+#define SCL_OEN		SCSPTR1_SPB0IO
+#define SCL		SCSPTR1_SPB0DT
+
+/* RICOH RS5C313 CE port */
+#define RS5C313_CE	0xB0000003
+
+/* RICOH RS5C313 CE port bit */
+#define RS5C313_CE_RTCCE	0x02
+
+/* SCSPTR1 data */
+unsigned char scsptr1_data;
+
+#define RS5C313_CEENABLE    ctrl_outb(RS5C313_CE_RTCCE, RS5C313_CE);
+#define RS5C313_CEDISABLE   ctrl_outb(0x00, RS5C313_CE)
+#define RS5C313_MISCOP      ctrl_outb(0x02, 0xB0000008)
+
+static void rs5c313_init_port(void)
+{
+	/* Set SCK as I/O port and Initialize SCSPTR1 data & I/O port. */
+	ctrl_outb(ctrl_inb(SCSMR1) & ~SCSMR1_CA, SCSMR1);
+	ctrl_outb(ctrl_inb(SCSCR1) & ~SCSCR1_CKE, SCSCR1);
+
+	/* And Initialize SCL for RS5C313 clock */
+	scsptr1_data = ctrl_inb(SCSPTR1) | SCL;	/* SCL:H */
+	ctrl_outb(scsptr1_data, SCSPTR1);
+	scsptr1_data = ctrl_inb(SCSPTR1) | SCL_OEN;	/* SCL output enable */
+	ctrl_outb(scsptr1_data, SCSPTR1);
+	RS5C313_CEDISABLE;	/* CE:L */
+}
+
+static void rs5c313_write_data(unsigned char data)
+{
+	int i;
+
+	for (i = 0; i < 8; i++) {
+		/* SDA:Write Data */
+		scsptr1_data = (scsptr1_data & ~SDA) |
+				((((0x80 >> i) & data) >> (7 - i)) << 2);
+		ctrl_outb(scsptr1_data, SCSPTR1);
+		if (i == 0) {
+			scsptr1_data |= SDA_OEN;	/* SDA:output enable */
+			ctrl_outb(scsptr1_data, SCSPTR1);
+		}
+		ndelay(700);
+		scsptr1_data &= ~SCL;	/* SCL:L */
+		ctrl_outb(scsptr1_data, SCSPTR1);
+		ndelay(700);
+		scsptr1_data |= SCL;	/* SCL:H */
+		ctrl_outb(scsptr1_data, SCSPTR1);
+	}
+
+	scsptr1_data &= ~SDA_OEN;	/* SDA:output disable */
+	ctrl_outb(scsptr1_data, SCSPTR1);
+}
+
+static unsigned char rs5c313_read_data(void)
+{
+	int i;
+	unsigned char data;
+
+	for (i = 0; i < 8; i++) {
+		ndelay(700);
+		/* SDA:Read Data */
+		data |= ((ctrl_inb(SCSPTR1) & SDA) >> 2) << (7 - i);
+		scsptr1_data &= ~SCL;	/* SCL:L */
+		ctrl_outb(scsptr1_data, SCSPTR1);
+		ndelay(700);
+		scsptr1_data |= SCL;	/* SCL:H */
+		ctrl_outb(scsptr1_data, SCSPTR1);
+	}
+	return data & 0x0F;
+}
+
+#endif /* CONFIG_SH_LANDISK */
+
+/*****************************************************/
+/* machine independence part of RS5C313              */
+/*****************************************************/
+
+/* RICOH RS5C313 address */
+#define RS5C313_ADDR_SEC	0x00
+#define RS5C313_ADDR_SEC10	0x01
+#define RS5C313_ADDR_MIN	0x02
+#define RS5C313_ADDR_MIN10	0x03
+#define RS5C313_ADDR_HOUR	0x04
+#define RS5C313_ADDR_HOUR10	0x05
+#define RS5C313_ADDR_WEEK	0x06
+#define RS5C313_ADDR_INTINTVREG	0x07
+#define RS5C313_ADDR_DAY	0x08
+#define RS5C313_ADDR_DAY10	0x09
+#define RS5C313_ADDR_MON	0x0A
+#define RS5C313_ADDR_MON10	0x0B
+#define RS5C313_ADDR_YEAR	0x0C
+#define RS5C313_ADDR_YEAR10	0x0D
+#define RS5C313_ADDR_CNTREG	0x0E
+#define RS5C313_ADDR_TESTREG	0x0F
+
+/* RICOH RS5C313 control register */
+#define RS5C313_CNTREG_ADJ_BSY	0x01
+#define RS5C313_CNTREG_WTEN_XSTP	0x02
+#define RS5C313_CNTREG_12_24	0x04
+#define RS5C313_CNTREG_CTFG	0x08
+
+/* RICOH RS5C313 test register */
+#define RS5C313_TESTREG_TEST	0x01
+
+/* RICOH RS5C313 control bit */
+#define RS5C313_CNTBIT_READ	0x40
+#define RS5C313_CNTBIT_AD	0x20
+#define RS5C313_CNTBIT_DT	0x10
+
+static unsigned char rs5c313_read_reg(unsigned char addr)
+{
+
+	rs5c313_write_data(addr | RS5C313_CNTBIT_READ | RS5C313_CNTBIT_AD);
+	return rs5c313_read_data();
+}
+
+static void rs5c313_write_reg(unsigned char addr, unsigned char data)
+{
+	data &= 0x0f;
+	rs5c313_write_data(addr | RS5C313_CNTBIT_AD);
+	rs5c313_write_data(data | RS5C313_CNTBIT_DT);
+	return;
+}
+
+static inline unsigned char rs5c313_read_cntreg(unsigned char addr)
+{
+	return rs5c313_read_reg(RS5C313_ADDR_CNTREG);
+}
+
+static inline void rs5c313_write_cntreg(unsigned char data)
+{
+	rs5c313_write_reg(RS5C313_ADDR_CNTREG, data);
+}
+
+static inline void rs5c313_write_intintvreg(unsigned char data)
+{
+	rs5c313_write_reg(RS5C313_ADDR_INTINTVREG, data);
+}
+
+static int rs5c313_rtc_read_time(struct device *dev, struct rtc_time *tm)
+{
+	int data;
+
+	while (1) {
+		RS5C313_CEENABLE;	/* CE:H */
+
+		/* Initialize control reg. 24 hour */
+		rs5c313_write_cntreg(0x04);
+
+		if (!(rs5c313_read_cntreg() & RS5C313_CNTREG_ADJ_BSY))
+			break;
+
+		RS5C313_CEDISABLE;
+		ndelay(700);	/* CE:L */
+
+	}
+
+	data = rs5c313_read_reg(RS5C313_ADDR_SEC);
+	data |= (rs5c313_read_reg(RS5C313_ADDR_SEC10) << 4);
+	tm->tm_sec = BCD2BIN(data);
+
+	data = rs5c313_read_reg(RS5C313_ADDR_MIN);
+	data |= (rs5c313_read_reg(RS5C313_ADDR_MIN10) << 4);
+	tm->tm_min = BCD2BIN(data);
+
+	data = rs5c313_read_reg(RS5C313_ADDR_HOUR);
+	data |= (rs5c313_read_reg(RS5C313_ADDR_HOUR10) << 4);
+	tm->tm_hour = BCD2BIN(data);
+
+	data = rs5c313_read_reg(RS5C313_ADDR_DAY);
+	data |= (rs5c313_read_reg(RS5C313_ADDR_DAY10) << 4);
+	tm->tm_mday = BCD2BIN(data);
+
+	data = rs5c313_read_reg(RS5C313_ADDR_MON);
+	data |= (rs5c313_read_reg(RS5C313_ADDR_MON10) << 4);
+	tm->tm_mon = BCD2BIN(data) - 1;
+
+	data = rs5c313_read_reg(RS5C313_ADDR_YEAR);
+	data |= (rs5c313_read_reg(RS5C313_ADDR_YEAR10) << 4);
+	tm->tm_year = BCD2BIN(data);
+
+	if (tm->tm_year < 70)
+		tm->tm_year += 100;
+
+	data = rs5c313_read_reg(RS5C313_ADDR_WEEK);
+	tm->tm_wday = BCD2BIN(data);
+
+	RS5C313_CEDISABLE;
+	ndelay(700);		/* CE:L */
+
+	return 0;
+}
+
+static int rs5c313_rtc_set_time(struct device *dev, struct rtc_time *tm)
+{
+	int data;
+
+	/* busy check. */
+	while (1) {
+		RS5C313_CEENABLE;	/* CE:H */
+
+		/* Initiatlize control reg. 24 hour */
+		rs5c313_write_cntreg(0x04);
+
+		if (!(rs5c313_read_cntreg() & RS5C313_CNTREG_ADJ_BSY))
+			break;
+		RS5C313_MISCOP;
+		RS5C313_CEDISABLE;
+		ndelay(700);	/* CE:L */
+	}
+
+	data = BIN2BCD(tm->tm_sec);
+	rs5c313_write_reg(RS5C313_ADDR_SEC, data);
+	rs5c313_write_reg(RS5C313_ADDR_SEC10, (data >> 4));
+
+	data = BIN2BCD(tm->tm_min);
+	rs5c313_write_reg(RS5C313_ADDR_MIN, data );
+	rs5c313_write_reg(RS5C313_ADDR_MIN10, (data >> 4));
+
+	data = BIN2BCD(tm->tm_hour);
+	rs5c313_write_reg(RS5C313_ADDR_HOUR, data);
+	rs5c313_write_reg(RS5C313_ADDR_HOUR10, (data >> 4));
+
+	data = BIN2BCD(tm->tm_mday);
+	rs5c313_write_reg(RS5C313_ADDR_DAY, data);
+	rs5c313_write_reg(RS5C313_ADDR_DAY10, (data>> 4));
+
+	data = BIN2BCD(tm->tm_mon + 1);
+	rs5c313_write_reg(RS5C313_ADDR_MON, data);
+	rs5c313_write_reg(RS5C313_ADDR_MON10, (data >> 4));
+
+	data = BIN2BCD(tm->tm_year % 100);
+	rs5c313_write_reg(RS5C313_ADDR_YEAR, data);
+	rs5c313_write_reg(RS5C313_ADDR_YEAR10, (data >> 4));
+
+	data = BIN2BCD(tm->tm_wday);
+	rs5c313_write_reg(RS5C313_ADDR_WEEK, data);
+
+	RS5C313_CEDISABLE;	/* CE:H */
+	ndelay(700);
+
+	return 0;
+}
+
+static void rs5c313_check_xstp_bit(void)
+{
+	struct rtc_time tm;
+
+	RS5C313_CEENABLE;	/* CE:H */
+	if (rs5c313_read_cntreg() & RS5C313_CNTREG_WTEN_XSTP) {
+		/* INT interval reg. OFF */
+		rs5c313_write_intintvreg(0x00);
+		/* Initialize control reg. 24 hour & adjust */
+		rs5c313_write_cntreg(0x07);
+
+		/* busy check. */
+		while (rs5c313_read_cntreg() & RS5C313_CNTREG_ADJ_BSY)
+			RS5C313_MISCOP;
+
+		memset(&tm, 0, sizeof(struct rtc_time));
+		tm.tm_mday 	= 1;
+		tm.tm_mon 	= 1;
+
+		rs5c313_rtc_set_time(NULL, &tm);
+		printk(KERN_ERR "RICHO RS5C313: invalid value, resetting to "
+				"1 Jan 2000\n");
+	}
+	RS5C313_CEDISABLE;
+	ndelay(700);		/* CE:L */
+}
+
+static const struct rtc_class_ops rs5c313_rtc_ops = {
+	.read_time = rs5c313_rtc_read_time,
+	.set_time = rs5c313_rtc_set_time,
+};
+
+static int rs5c313_rtc_probe(struct platform_device *pdev)
+{
+	struct rtc_device *rtc = rtc_device_register("rs5c313", &pdev->dev,
+				&rs5c313_rtc_ops, THIS_MODULE);
+
+	if (IS_ERR(rtc))
+		return PTR_ERR(rtc);
+
+	platform_set_drvdata(pdev, rtc);
+
+	return err;
+}
+
+static int __devexit rs5c313_rtc_remove(struct platform_device *pdev)
+{
+	struct rtc_device *rtc = platform_get_drvdata( pdev );
+
+	rtc_device_unregister(rtc);
+
+	return 0;
+}
+
+static struct platform_driver rs5c313_rtc_platform_driver = {
+	.driver         = {
+		.name   = DRV_NAME,
+		.owner  = THIS_MODULE,
+	},
+	.probe 	= rs5c313_rtc_probe,
+	.remove = __devexit_p( rs5c313_rtc_remove ),
+};
+
+static int __init rs5c313_rtc_init(void)
+{
+	int err;
+
+	err = platform_driver_register(&rs5c313_rtc_platform_driver);
+	if (err)
+		return err;
+
+	rs5c313_init_port();
+	rs5c313_check_xstp_bit();
+
+	return 0;
+}
+
+static void __exit rs5c313_rtc_exit(void)
+{
+	platform_driver_unregister( &rs5c313_rtc_platform_driver );
+}
+
+module_init(rs5c313_rtc_init);
+module_exit(rs5c313_rtc_exit);
+
+MODULE_VERSION(DRV_VERSION);
+MODULE_AUTHOR("kogiidena , Nobuhiro Iwamatsu <iwamatsu@nigauri.org>");
+MODULE_DESCRIPTION("Ricoh RS5C313 RTC device driver");
+MODULE_LICENSE("GPL");