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");