[PATCH/RFC 14/16] rtc: Add an RTC driver for the Oki MSM6242

Geert Uytterhoeven
2009-04-18T18:52:31Z

Cc: rtc-linux@googlegroups.com
---
drivers/rtc/Kconfig | 9 ++
drivers/rtc/Makefile | 1 +
drivers/rtc/rtc-msm6242.c | 285 +++++++++++++++++++++++++++++++++++++++++++++
3 files changed, 295 insertions(+), 0 deletions(-)
create mode 100644 drivers/rtc/rtc-msm6242.c

diff --git a/drivers/rtc/Kconfig b/drivers/rtc/Kconfig
index ffe34a1..a0f6297 100644
--- a/drivers/rtc/Kconfig
+++ b/drivers/rtc/Kconfig
@@ -526,6 +526,15 @@ config RTC_DRV_PCF50633
If you say yes here you get support for the RTC subsystem of the
NXP PCF50633 used in embedded systems.

+config RTC_DRV_MSM6242
+ tristate "Oki MSM6242"
+ help
+ If you say yes here you get support for the Oki MSM6242
+ timekeeping chip. It is used in some Amiga models (e.g. A2000).
+
+ This driver can also be built as a module. If so, the module
+ will be called rtc-msm6242.
+
comment "on-CPU RTC drivers"

config RTC_DRV_OMAP
diff --git a/drivers/rtc/Makefile b/drivers/rtc/Makefile
index 6c0639a..c70418b 100644
--- a/drivers/rtc/Makefile
+++ b/drivers/rtc/Makefile
@@ -76,4 +76,5 @@ obj-$(CONFIG_RTC_DRV_VR41XX) += rtc-vr41xx.o
obj-$(CONFIG_RTC_DRV_WM8350) += rtc-wm8350.o
obj-$(CONFIG_RTC_DRV_X1205) += rtc-x1205.o
obj-$(CONFIG_RTC_DRV_PCF50633) += rtc-pcf50633.o
+obj-$(CONFIG_RTC_DRV_MSM6242) += rtc-msm6242.o
obj-$(CONFIG_RTC_DRV_PS3) += rtc-ps3.o
diff --git a/drivers/rtc/rtc-msm6242.c b/drivers/rtc/rtc-msm6242.c
new file mode 100644
index 0000000..c3af4f8
--- /dev/null
+++ b/drivers/rtc/rtc-msm6242.c
@@ -0,0 +1,285 @@
+/*
+ * Oki MSM6242 RTC Driver
+ *
+ * Copyright 2009 Geert Uytterhoeven
+ *
+ * Based on the A2000 TOD code in arch/m68k/amiga/config.c
+ * Copyright (C) 1993 Hamish Macdonald
+ */
+
+#include <linux/delay.h>
+#include <linux/io.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/platform_device.h>
+#include <linux/rtc.h>
+
+
+enum {
+ MSM6242_SECOND1 = 0x0, /* 1-second digit register */
+ MSM6242_SECOND10 = 0x1, /* 10-second digit register */
+ MSM6242_MINUTE1 = 0x2, /* 1-minute digit register */
+ MSM6242_MINUTE10 = 0x3, /* 10-minute digit register */
+ MSM6242_HOUR1 = 0x4, /* 1-hour digit register */
+ MSM6242_HOUR10 = 0x5, /* PM/AM, 10-hour digit register */
+ MSM6242_DAY1 = 0x6, /* 1-day digit register */
+ MSM6242_DAY10 = 0x7, /* 10-day digit register */
+ MSM6242_MONTH1 = 0x8, /* 1-month digit register */
+ MSM6242_MONTH10 = 0x9, /* 10-month digit register */
+ MSM6242_YEAR1 = 0xa, /* 1-year digit register */
+ MSM6242_YEAR10 = 0xb, /* 10-year digit register */
+ MSM6242_WEEK = 0xc, /* Week register */
+ MSM6242_CD = 0xd, /* Control Register D */
+ MSM6242_CE = 0xe, /* Control Register E */
+ MSM6242_CF = 0xf, /* Control Register F */
+};
+
+#define MSM6242_HOUR10_AM (0 << 2)
+#define MSM6242_HOUR10_PM (1 << 2)
+#define MSM6242_HOUR10_HR_MASK (3 << 0)
+
+#define MSM6242_WEEK_SUNDAY 0
+#define MSM6242_WEEK_MONDAY 1
+#define MSM6242_WEEK_TUESDAY 2
+#define MSM6242_WEEK_WEDNESDAY 3
+#define MSM6242_WEEK_THURSDAY 4
+#define MSM6242_WEEK_FRIDAY 5
+#define MSM6242_WEEK_SATURDAY 6
+
+#define MSM6242_CD_30_S_ADJ (1 << 3) /* 30-second adjustment */
+#define MSM6242_CD_IRQ_FLAG (1 << 2)
+#define MSM6242_CD_BUSY (1 << 1)
+#define MSM6242_CD_HOLD (1 << 0)
+
+#define MSM6242_CE_T_MASK (3 << 2)
+#define MSM6242_CE_T_64HZ (0 << 2) /* period 1/64 second */
+#define MSM6242_CE_T_1HZ (1 << 2) /* period 1 second */
+#define MSM6242_CE_T_1MINUTE (2 << 2) /* period 1 minute */
+#define MSM6242_CE_T_1HOUR (3 << 2) /* period 1 hour */
+
+#define MSM6242_CE_ITRPT_STND (1 << 1)
+#define MSM6242_CE_MASK (1 << 0) /* STD.P output control */
+
+#define MSM6242_CF_TEST (1 << 3)
+#define MSM6242_CF_12H (0 << 2)
+#define MSM6242_CF_24H (1 << 2)
+#define MSM6242_CF_STOP (1 << 1)
+#define MSM6242_CF_REST (1 << 0) /* reset */
+
+
+struct msm6242_priv {
+ u32 __iomem *regs;
+ struct rtc_device *rtc;
+};
+
+static inline unsigned int msm6242_read(struct msm6242_priv *priv,
+ unsigned int reg)
+{
+ return __raw_readl(&priv->regs[reg]) & 0xf;
+}
+
+static inline void msm6242_write(struct msm6242_priv *priv, unsigned int val,
+ unsigned int reg)
+{
+ return __raw_writel(val, &priv->regs[reg]);
+}
+
+static inline void msm6242_set(struct msm6242_priv *priv, unsigned int val,
+ unsigned int reg)
+{
+ msm6242_write(priv, msm6242_read(priv, reg) | val, reg);
+}
+
+static inline void msm6242_clear(struct msm6242_priv *priv, unsigned int val,
+ unsigned int reg)
+{
+ msm6242_write(priv, msm6242_read(priv, reg) & ~val, reg);
+}
+
+static void msm6242_lock(struct msm6242_priv *priv)
+{
+ int cnt = 5;
+
+ msm6242_set(priv, MSM6242_CD_HOLD, MSM6242_CD);
+
+ while ((msm6242_read(priv, MSM6242_CD) & MSM6242_CD_BUSY) && cnt--) {
+ msm6242_clear(priv, MSM6242_CD_HOLD, MSM6242_CD);
+ udelay(70);
+ msm6242_set(priv, MSM6242_CD_HOLD, MSM6242_CD);
+ }
+
+ if (!cnt)
+ pr_warning("msm6242: timed out waiting for RTC (0x%x)\n",
+ msm6242_read(priv, MSM6242_CD));
+}
+
+static void msm6242_unlock(struct msm6242_priv *priv)
+{
+ msm6242_clear(priv, MSM6242_CD_HOLD, MSM6242_CD);
+}
+
+static int msm6242_read_time(struct device *dev, struct rtc_time *tm)
+{
+ struct msm6242_priv *priv = dev_get_drvdata(dev);
+
+ msm6242_lock(priv);
+
+ tm->tm_sec = msm6242_read(priv, MSM6242_SECOND10) * 10 +
+ msm6242_read(priv, MSM6242_SECOND1);
+ tm->tm_min = msm6242_read(priv, MSM6242_MINUTE10) * 10 +
+ msm6242_read(priv, MSM6242_MINUTE1);
+ tm->tm_hour = (msm6242_read(priv, MSM6242_HOUR10 & 3)) * 10 +
+ msm6242_read(priv, MSM6242_HOUR1);
+ tm->tm_mday = msm6242_read(priv, MSM6242_DAY10) * 10 +
+ msm6242_read(priv, MSM6242_DAY1);
+ tm->tm_wday = msm6242_read(priv, MSM6242_WEEK);
+ tm->tm_mon = msm6242_read(priv, MSM6242_MONTH10) * 10 +
+ msm6242_read(priv, MSM6242_MONTH1) - 1;
+ tm->tm_year = msm6242_read(priv, MSM6242_YEAR10) * 10 +
+ msm6242_read(priv, MSM6242_YEAR1);
+ if (tm->tm_year <= 69)
+ tm->tm_year += 100;
+
+ if (!(msm6242_read(priv, MSM6242_CF) & MSM6242_CF_24H)) {
+ unsigned int pm = msm6242_read(priv, MSM6242_HOUR10) &
+ MSM6242_HOUR10_PM;
+ if (!pm && tm->tm_hour == 12)
+ tm->tm_hour = 0;
+ else if (pm && tm->tm_hour != 12)
+ tm->tm_hour += 12;
+ }
+
+ msm6242_unlock(priv);
+
+ return rtc_valid_tm(tm);
+}
+
+static int msm6242_set_time(struct device *dev, struct rtc_time *tm)
+{
+ struct msm6242_priv *priv = dev_get_drvdata(dev);
+
+ msm6242_lock(priv);
+
+ msm6242_write(priv, tm->tm_sec / 10, MSM6242_SECOND10);
+ msm6242_write(priv, tm->tm_sec % 10, MSM6242_SECOND1);
+ msm6242_write(priv, tm->tm_min / 10, MSM6242_MINUTE10);
+ msm6242_write(priv, tm->tm_min % 10, MSM6242_MINUTE1);
+ if (msm6242_read(priv, MSM6242_CF) & MSM6242_CF_24H)
+ msm6242_write(priv, tm->tm_hour / 10, MSM6242_HOUR10);
+ else if (tm->tm_hour >= 12)
+ msm6242_write(priv, MSM6242_HOUR10_PM + (tm->tm_hour - 12) / 10,
+ MSM6242_HOUR10);
+ else
+ msm6242_write(priv, tm->tm_hour / 10, MSM6242_HOUR10);
+ msm6242_write(priv, tm->tm_hour % 10, MSM6242_HOUR1);
+ msm6242_write(priv, tm->tm_mday / 10, MSM6242_DAY10);
+ msm6242_write(priv, tm->tm_mday % 10, MSM6242_DAY1);
+ if (tm->tm_wday != -1)
+ msm6242_write(priv, tm->tm_wday, MSM6242_WEEK);
+ msm6242_write(priv, (tm->tm_mon + 1) / 10, MSM6242_MONTH10);
+ msm6242_write(priv, (tm->tm_mon + 1) % 10, MSM6242_MONTH1);
+ if (tm->tm_year >= 100)
+ tm->tm_year -= 100;
+ msm6242_write(priv, tm->tm_year / 10, MSM6242_YEAR10);
+ msm6242_write(priv, tm->tm_year % 10, MSM6242_YEAR1);
+
+ msm6242_unlock(priv);
+ return 0;
+}
+
+static int msm6242_set_mmss(struct device *dev, unsigned long secs)
+{
+ struct msm6242_priv *priv = dev_get_drvdata(dev);
+ unsigned int real_seconds = secs % 60, real_minutes = (secs / 60) % 60;
+
+ msm6242_lock(priv);
+
+ msm6242_write(priv, real_seconds / 10, MSM6242_SECOND10);
+ msm6242_write(priv, real_seconds % 10, MSM6242_SECOND1);
+ msm6242_write(priv, real_minutes / 10, MSM6242_MINUTE10);
+ msm6242_write(priv, real_minutes % 10, MSM6242_MINUTE1);
+
+ msm6242_unlock(priv);
+ return 0;
+}
+
+static const struct rtc_class_ops msm6242_rtc_ops = {
+ .read_time = msm6242_read_time,
+ .set_time = msm6242_set_time,
+ .set_mmss = msm6242_set_mmss,
+};
+
+static int __init msm6242_rtc_probe(struct platform_device *dev)
+{
+ struct resource *res;
+ struct msm6242_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-msm6242", &dev->dev, &msm6242_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 msm6242_rtc_remove(struct platform_device *dev)
+{
+ struct msm6242_priv *priv = platform_get_drvdata(dev);
+
+ rtc_device_unregister(priv->rtc);
+ iounmap(priv->regs);
+ kfree(priv);
+ return 0;
+}
+
+static struct platform_driver msm6242_rtc_driver = {
+ .driver = {
+ .name = "rtc-msm6242",
+ .owner = THIS_MODULE,
+ },
+ .remove = __exit_p(msm6242_rtc_remove),
+};
+
+static int __init msm6242_rtc_init(void)
+{
+ return platform_driver_probe(&msm6242_rtc_driver, msm6242_rtc_probe);
+}
+
+static void __exit msm6242_rtc_fini(void)
+{
+ platform_driver_unregister(&msm6242_rtc_driver);
+}
+
+module_init(msm6242_rtc_init);
+module_exit(msm6242_rtc_fini);
+
+MODULE_AUTHOR("Geert Uytterhoeven");
+MODULE_LICENSE("GPL");
+MODULE_DESCRIPTION("Oki MSM6242 RTC driver");
+MODULE_ALIAS("platform:rtc-msm6242");
--
1.6.2.3