rtc: Add an RTC driver for the Ricoh RP5C01

Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Acked-by: Alessandro Zummo <alessandro.zummo@towertech.it>

1 files changed, 222 insertions, 0 deletions

diff --git a/drivers/rtc/rtc-rp5c01.c b/drivers/rtc/rtc-rp5c01.c
new file mode 100644
index 000000000000..e1313feb060f
--- /dev/null
+++ b/drivers/rtc/rtc-rp5c01.c
@@ -0,0 +1,222 @@
+/*
+ *  Ricoh RP5C01 RTC Driver
+ *
+ *  Copyright 2009 Geert Uytterhoeven
+ *
+ *  Based on the A3000 TOD code in arch/m68k/amiga/config.c
+ *  Copyright (C) 1993 Hamish Macdonald
+ */
+
+#include <linux/io.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/platform_device.h>
+#include <linux/rtc.h>
+
+
+enum {
+        RP5C01_1_SECOND         = 0x0,  /* MODE 00 */
+        RP5C01_10_SECOND        = 0x1,  /* MODE 00 */
+        RP5C01_1_MINUTE         = 0x2,  /* MODE 00 and MODE 01 */
+        RP5C01_10_MINUTE        = 0x3,  /* MODE 00 and MODE 01 */
+        RP5C01_1_HOUR           = 0x4,  /* MODE 00 and MODE 01 */
+        RP5C01_10_HOUR          = 0x5,  /* MODE 00 and MODE 01 */
+        RP5C01_DAY_OF_WEEK      = 0x6,  /* MODE 00 and MODE 01 */
+        RP5C01_1_DAY            = 0x7,  /* MODE 00 and MODE 01 */
+        RP5C01_10_DAY           = 0x8,  /* MODE 00 and MODE 01 */
+        RP5C01_1_MONTH          = 0x9,  /* MODE 00 */
+        RP5C01_10_MONTH         = 0xa,  /* MODE 00 */
+        RP5C01_1_YEAR           = 0xb,  /* MODE 00 */
+        RP5C01_10_YEAR          = 0xc,  /* MODE 00 */
+
+        RP5C01_12_24_SELECT     = 0xa,  /* MODE 01 */
+        RP5C01_LEAP_YEAR        = 0xb,  /* MODE 01 */
+
+        RP5C01_MODE             = 0xd,  /* all modes */
+        RP5C01_TEST             = 0xe,  /* all modes */
+        RP5C01_RESET            = 0xf,  /* all modes */
+};
+
+#define RP5C01_12_24_SELECT_12  (0 << 0)
+#define RP5C01_12_24_SELECT_24  (1 << 0)
+
+#define RP5C01_10_HOUR_AM       (0 << 1)
+#define RP5C01_10_HOUR_PM       (1 << 1)
+
+#define RP5C01_MODE_TIMER_EN    (1 << 3)        /* timer enable */
+#define RP5C01_MODE_ALARM_EN    (1 << 2)        /* alarm enable */
+
+#define RP5C01_MODE_MODE_MASK   (3 << 0)
+#define RP5C01_MODE_MODE00      (0 << 0)        /* time */
+#define RP5C01_MODE_MODE01      (1 << 0)        /* alarm, 12h/24h, leap year */
+#define RP5C01_MODE_RAM_BLOCK10 (2 << 0)        /* RAM 4 bits x 13 */
+#define RP5C01_MODE_RAM_BLOCK11 (3 << 0)        /* RAM 4 bits x 13 */
+
+#define RP5C01_RESET_1HZ_PULSE  (1 << 3)
+#define RP5C01_RESET_16HZ_PULSE (1 << 2)
+#define RP5C01_RESET_SECOND     (1 << 1)        /* reset divider stages for */
+                                                /* seconds or smaller units */
+#define RP5C01_RESET_ALARM      (1 << 0)        /* reset all alarm registers */
+
+
+struct rp5c01_priv {
+        u32 __iomem *regs;
+        struct rtc_device *rtc;
+};
+
+static inline unsigned int rp5c01_read(struct rp5c01_priv *priv,
+                                       unsigned int reg)
+{
+        return __raw_readl(&priv->regs[reg]) & 0xf;
+}
+
+static inline void rp5c01_write(struct rp5c01_priv *priv, unsigned int val,
+                                unsigned int reg)
+{
+        return __raw_writel(val, &priv->regs[reg]);
+}
+
+static void rp5c01_lock(struct rp5c01_priv *priv)
+{
+        rp5c01_write(priv, RP5C01_MODE_MODE00, RP5C01_MODE);
+}
+
+static void rp5c01_unlock(struct rp5c01_priv *priv)
+{
+        rp5c01_write(priv, RP5C01_MODE_TIMER_EN | RP5C01_MODE_MODE01,
+                     RP5C01_MODE);
+}
+
+static int rp5c01_read_time(struct device *dev, struct rtc_time *tm)
+{
+        struct rp5c01_priv *priv = dev_get_drvdata(dev);
+
+        rp5c01_lock(priv);
+
+        tm->tm_sec  = rp5c01_read(priv, RP5C01_10_SECOND) * 10 +
+                      rp5c01_read(priv, RP5C01_1_SECOND);
+        tm->tm_min  = rp5c01_read(priv, RP5C01_10_MINUTE) * 10 +
+                      rp5c01_read(priv, RP5C01_1_MINUTE);
+        tm->tm_hour = rp5c01_read(priv, RP5C01_10_HOUR) * 10 +
+                      rp5c01_read(priv, RP5C01_1_HOUR);
+        tm->tm_mday = rp5c01_read(priv, RP5C01_10_DAY) * 10 +
+                      rp5c01_read(priv, RP5C01_1_DAY);
+        tm->tm_wday = rp5c01_read(priv, RP5C01_DAY_OF_WEEK);
+        tm->tm_mon  = rp5c01_read(priv, RP5C01_10_MONTH) * 10 +
+                      rp5c01_read(priv, RP5C01_1_MONTH) - 1;
+        tm->tm_year = rp5c01_read(priv, RP5C01_10_YEAR) * 10 +
+                      rp5c01_read(priv, RP5C01_1_YEAR);
+        if (tm->tm_year <= 69)
+                tm->tm_year += 100;
+
+        rp5c01_unlock(priv);
+
+        return rtc_valid_tm(tm);
+}
+
+static int rp5c01_set_time(struct device *dev, struct rtc_time *tm)
+{
+        struct rp5c01_priv *priv = dev_get_drvdata(dev);
+
+        rp5c01_lock(priv);
+
+        rp5c01_write(priv, tm->tm_sec / 10, RP5C01_10_SECOND);
+        rp5c01_write(priv, tm->tm_sec % 10, RP5C01_1_SECOND);
+        rp5c01_write(priv, tm->tm_min / 10, RP5C01_10_MINUTE);
+        rp5c01_write(priv, tm->tm_min % 10, RP5C01_1_MINUTE);
+        rp5c01_write(priv, tm->tm_hour / 10, RP5C01_10_HOUR);
+        rp5c01_write(priv, tm->tm_hour % 10, RP5C01_1_HOUR);
+        rp5c01_write(priv, tm->tm_mday / 10, RP5C01_10_DAY);
+        rp5c01_write(priv, tm->tm_mday % 10, RP5C01_1_DAY);
+        if (tm->tm_wday != -1)
+                rp5c01_write(priv, tm->tm_wday, RP5C01_DAY_OF_WEEK);
+        rp5c01_write(priv, (tm->tm_mon + 1) / 10, RP5C01_10_MONTH);
+        rp5c01_write(priv, (tm->tm_mon + 1) % 10, RP5C01_1_MONTH);
+        if (tm->tm_year >= 100)
+                tm->tm_year -= 100;
+        rp5c01_write(priv, tm->tm_year / 10, RP5C01_10_YEAR);
+        rp5c01_write(priv, tm->tm_year % 10, RP5C01_1_YEAR);
+
+        rp5c01_unlock(priv);
+        return 0;
+}
+
+static const struct rtc_class_ops rp5c01_rtc_ops = {
+        .read_time      = rp5c01_read_time,
+        .set_time       = rp5c01_set_time,
+};
+
+static int __init rp5c01_rtc_probe(struct platform_device *dev)
+{
+        struct resource *res;
+        struct rp5c01_priv *priv;
+        struct rtc_device *rtc;
+        int error;
+
+        res = platform_get_resource(dev, IORESOURCE_MEM, 0);
+        if (!res)
+                return -ENODEV;
+
+        priv = kzalloc(sizeof(*priv), GFP_KERNEL);
+        if (!priv)
+                return -ENOMEM;
+
+        priv->regs = ioremap(res->start, resource_size(res));
+        if (!priv->regs) {
+                error = -ENOMEM;
+                goto out_free_priv;
+        }
+
+        rtc = rtc_device_register("rtc-rp5c01", &dev->dev, &rp5c01_rtc_ops,
+                                  THIS_MODULE);
+        if (IS_ERR(rtc)) {
+                error = PTR_ERR(rtc);
+                goto out_unmap;
+        }
+
+        priv->rtc = rtc;
+        platform_set_drvdata(dev, priv);
+        return 0;
+
+out_unmap:
+        iounmap(priv->regs);
+out_free_priv:
+        kfree(priv);
+        return error;
+}
+
+static int __exit rp5c01_rtc_remove(struct platform_device *dev)
+{
+        struct rp5c01_priv *priv = platform_get_drvdata(dev);
+
+        rtc_device_unregister(priv->rtc);
+        iounmap(priv->regs);
+        kfree(priv);
+        return 0;
+}
+
+static struct platform_driver rp5c01_rtc_driver = {
+        .driver = {
+                .name   = "rtc-rp5c01",
+                .owner  = THIS_MODULE,
+        },
+        .remove = __exit_p(rp5c01_rtc_remove),
+};
+
+static int __init rp5c01_rtc_init(void)
+{
+        return platform_driver_probe(&rp5c01_rtc_driver, rp5c01_rtc_probe);
+}
+
+static void __exit rp5c01_rtc_fini(void)
+{
+        platform_driver_unregister(&rp5c01_rtc_driver);
+}
+
+module_init(rp5c01_rtc_init);
+module_exit(rp5c01_rtc_fini);
+
+MODULE_AUTHOR("Geert Uytterhoeven <geert@linux-m68k.org>");
+MODULE_LICENSE("GPL");
+MODULE_DESCRIPTION("Ricoh RP5C01 RTC driver");
+MODULE_ALIAS("platform:rtc-rp5c01");