rtc: Enable rtc in max8925
authorHaojian Zhuang <haojian.zhuang@marvell.com>
Mon, 25 Jan 2010 11:30:29 +0000 (06:30 -0500)
committerSamuel Ortiz <sameo@linux.intel.com>
Sun, 7 Mar 2010 21:17:16 +0000 (22:17 +0100)
MAX8925 is a PMIC that contains RTC component.

Signed-off-by: Haojian Zhuang <haojian.zhuang@marvell.com>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
drivers/rtc/Kconfig
drivers/rtc/Makefile
drivers/rtc/rtc-max8925.c [new file with mode: 0644]

index 2bb8a8b..6a13037 100644 (file)
@@ -175,6 +175,16 @@ config RTC_DRV_MAX6900
          This driver can also be built as a module. If so, the module
          will be called rtc-max6900.
 
+config RTC_DRV_MAX8925
+       tristate "Maxim MAX8925"
+       depends on MFD_MAX8925
+       help
+         If you say yes here you will get support for the
+         RTC of Maxim MAX8925 PMIC.
+
+         This driver can also be built as a module. If so, the module
+         will be called rtc-max8925.
+
 config RTC_DRV_RS5C372
        tristate "Ricoh R2025S/D, RS5C372A/B, RV5C386, RV5C387A"
        help
index b7148af..44ef194 100644 (file)
@@ -52,6 +52,7 @@ obj-$(CONFIG_RTC_DRV_M48T59)  += rtc-m48t59.o
 obj-$(CONFIG_RTC_DRV_M48T86)   += rtc-m48t86.o
 obj-$(CONFIG_RTC_MXC)          += rtc-mxc.o
 obj-$(CONFIG_RTC_DRV_MAX6900)  += rtc-max6900.o
+obj-$(CONFIG_RTC_DRV_MAX8925)  += rtc-max8925.o
 obj-$(CONFIG_RTC_DRV_MAX6902)  += rtc-max6902.o
 obj-$(CONFIG_RTC_DRV_MC13783)  += rtc-mc13783.o
 obj-$(CONFIG_RTC_DRV_MSM6242)  += rtc-msm6242.o
diff --git a/drivers/rtc/rtc-max8925.c b/drivers/rtc/rtc-max8925.c
new file mode 100644 (file)
index 0000000..acdbb17
--- /dev/null
@@ -0,0 +1,314 @@
+/*
+ * RTC driver for Maxim MAX8925
+ *
+ * Copyright (C) 2009-2010 Marvell International Ltd.
+ *     Haojian Zhuang <haojian.zhuang@marvell.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/module.h>
+#include <linux/i2c.h>
+#include <linux/rtc.h>
+#include <linux/platform_device.h>
+#include <linux/mfd/max8925.h>
+
+enum {
+       RTC_SEC = 0,
+       RTC_MIN,
+       RTC_HOUR,
+       RTC_WEEKDAY,
+       RTC_DATE,
+       RTC_MONTH,
+       RTC_YEAR1,
+       RTC_YEAR2,
+};
+
+#define MAX8925_RTC_SEC                        0x00
+#define MAX8925_RTC_MIN                        0x01
+#define MAX8925_RTC_HOUR               0x02
+#define MAX8925_RTC_WEEKDAY            0x03
+#define MAX8925_RTC_DATE               0x04
+#define MAX8925_RTC_MONTH              0x05
+#define MAX8925_RTC_YEAR1              0x06
+#define MAX8925_RTC_YEAR2              0x07
+#define MAX8925_ALARM0_SEC             0x08
+#define MAX8925_ALARM0_MIN             0x09
+#define MAX8925_ALARM0_HOUR            0x0a
+#define MAX8925_ALARM0_WEEKDAY         0x0b
+#define MAX8925_ALARM0_DATE            0x0c
+#define MAX8925_ALARM0_MON             0x0d
+#define MAX8925_ALARM0_YEAR1           0x0e
+#define MAX8925_ALARM0_YEAR2           0x0f
+#define MAX8925_ALARM1_SEC             0x10
+#define MAX8925_ALARM1_MIN             0x11
+#define MAX8925_ALARM1_HOUR            0x12
+#define MAX8925_ALARM1_WEEKDAY         0x13
+#define MAX8925_ALARM1_DATE            0x14
+#define MAX8925_ALARM1_MON             0x15
+#define MAX8925_ALARM1_YEAR1           0x16
+#define MAX8925_ALARM1_YEAR2           0x17
+#define MAX8925_RTC_CNTL               0x1b
+#define MAX8925_RTC_STATUS             0x20
+
+#define TIME_NUM                       8
+#define ALARM_1SEC                     (1 << 7)
+#define HOUR_12                                (1 << 7)
+#define HOUR_AM_PM                     (1 << 5)
+#define ALARM0_IRQ                     (1 << 3)
+#define ALARM1_IRQ                     (1 << 2)
+#define ALARM0_STATUS                  (1 << 2)
+#define ALARM1_STATUS                  (1 << 1)
+
+
+struct max8925_rtc_info {
+       struct rtc_device       *rtc_dev;
+       struct max8925_chip     *chip;
+       struct i2c_client       *rtc;
+       struct device           *dev;
+};
+
+static irqreturn_t rtc_update_handler(int irq, void *data)
+{
+       struct max8925_rtc_info *info = (struct max8925_rtc_info *)data;
+
+       /* disable ALARM0 except for 1SEC alarm */
+       max8925_set_bits(info->rtc, MAX8925_ALARM0_CNTL, 0x7f, 0);
+       rtc_update_irq(info->rtc_dev, 1, RTC_IRQF | RTC_AF);
+       return IRQ_HANDLED;
+}
+
+static int tm_calc(struct rtc_time *tm, unsigned char *buf, int len)
+{
+       if (len < TIME_NUM)
+               return -EINVAL;
+       tm->tm_year = (buf[RTC_YEAR2] >> 4) * 1000
+                       + (buf[RTC_YEAR2] & 0xf) * 100
+                       + (buf[RTC_YEAR1] >> 4) * 10
+                       + (buf[RTC_YEAR1] & 0xf);
+       tm->tm_year -= 1900;
+       tm->tm_mon = ((buf[RTC_MONTH] >> 4) & 0x01) * 10
+                       + (buf[RTC_MONTH] & 0x0f);
+       tm->tm_mday = ((buf[RTC_DATE] >> 4) & 0x03) * 10
+                       + (buf[RTC_DATE] & 0x0f);
+       tm->tm_wday = buf[RTC_WEEKDAY] & 0x07;
+       if (buf[RTC_HOUR] & HOUR_12) {
+               tm->tm_hour = ((buf[RTC_HOUR] >> 4) & 0x1) * 10
+                               + (buf[RTC_HOUR] & 0x0f);
+               if (buf[RTC_HOUR] & HOUR_AM_PM)
+                       tm->tm_hour += 12;
+       } else
+               tm->tm_hour = ((buf[RTC_HOUR] >> 4) & 0x03) * 10
+                               + (buf[RTC_HOUR] & 0x0f);
+       tm->tm_min = ((buf[RTC_MIN] >> 4) & 0x7) * 10
+                       + (buf[RTC_MIN] & 0x0f);
+       tm->tm_sec = ((buf[RTC_SEC] >> 4) & 0x7) * 10
+                       + (buf[RTC_SEC] & 0x0f);
+       return 0;
+}
+
+static int data_calc(unsigned char *buf, struct rtc_time *tm, int len)
+{
+       unsigned char high, low;
+
+       if (len < TIME_NUM)
+               return -EINVAL;
+
+       high = (tm->tm_year + 1900) / 1000;
+       low = (tm->tm_year + 1900) / 100;
+       low = low - high * 10;
+       buf[RTC_YEAR2] = (high << 4) + low;
+       high = (tm->tm_year + 1900) / 10;
+       low = tm->tm_year + 1900;
+       low = low - high * 10;
+       high = high - (high / 10) * 10;
+       buf[RTC_YEAR1] = (high << 4) + low;
+       high = tm->tm_mon / 10;
+       low = tm->tm_mon;
+       low = low - high * 10;
+       buf[RTC_MONTH] = (high << 4) + low;
+       high = tm->tm_mday / 10;
+       low = tm->tm_mday;
+       low = low - high * 10;
+       buf[RTC_DATE] = (high << 4) + low;
+       buf[RTC_WEEKDAY] = tm->tm_wday;
+       high = tm->tm_hour / 10;
+       low = tm->tm_hour;
+       low = low - high * 10;
+       buf[RTC_HOUR] = (high << 4) + low;
+       high = tm->tm_min / 10;
+       low = tm->tm_min;
+       low = low - high * 10;
+       buf[RTC_MIN] = (high << 4) + low;
+       high = tm->tm_sec / 10;
+       low = tm->tm_sec;
+       low = low - high * 10;
+       buf[RTC_SEC] = (high << 4) + low;
+       return 0;
+}
+
+static int max8925_rtc_read_time(struct device *dev, struct rtc_time *tm)
+{
+       struct max8925_rtc_info *info = dev_get_drvdata(dev);
+       unsigned char buf[TIME_NUM];
+       int ret;
+
+       ret = max8925_bulk_read(info->rtc, MAX8925_RTC_SEC, TIME_NUM, buf);
+       if (ret < 0)
+               goto out;
+       ret = tm_calc(tm, buf, TIME_NUM);
+out:
+       return ret;
+}
+
+static int max8925_rtc_set_time(struct device *dev, struct rtc_time *tm)
+{
+       struct max8925_rtc_info *info = dev_get_drvdata(dev);
+       unsigned char buf[TIME_NUM];
+       int ret;
+
+       ret = data_calc(buf, tm, TIME_NUM);
+       if (ret < 0)
+               goto out;
+       ret = max8925_bulk_write(info->rtc, MAX8925_RTC_SEC, TIME_NUM, buf);
+out:
+       return ret;
+}
+
+static int max8925_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *alrm)
+{
+       struct max8925_rtc_info *info = dev_get_drvdata(dev);
+       unsigned char buf[TIME_NUM];
+       int ret;
+
+       ret = max8925_bulk_read(info->rtc, MAX8925_ALARM0_SEC, TIME_NUM, buf);
+       if (ret < 0)
+               goto out;
+       ret = tm_calc(&alrm->time, buf, TIME_NUM);
+       if (ret < 0)
+               goto out;
+       ret = max8925_reg_read(info->rtc, MAX8925_RTC_IRQ_MASK);
+       if (ret < 0)
+               goto out;
+       if ((ret & ALARM0_IRQ) == 0)
+               alrm->enabled = 1;
+       else
+               alrm->enabled = 0;
+       ret = max8925_reg_read(info->rtc, MAX8925_RTC_STATUS);
+       if (ret < 0)
+               goto out;
+       if (ret & ALARM0_STATUS)
+               alrm->pending = 1;
+       else
+               alrm->pending = 0;
+out:
+       return ret;
+}
+
+static int max8925_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alrm)
+{
+       struct max8925_rtc_info *info = dev_get_drvdata(dev);
+       unsigned char buf[TIME_NUM];
+       int ret;
+
+       ret = data_calc(buf, &alrm->time, TIME_NUM);
+       if (ret < 0)
+               goto out;
+       ret = max8925_bulk_write(info->rtc, MAX8925_ALARM0_SEC, TIME_NUM, buf);
+       if (ret < 0)
+               goto out;
+       /* only enable alarm on year/month/day/hour/min/sec */
+       ret = max8925_reg_write(info->rtc, MAX8925_ALARM0_CNTL, 0x77);
+       if (ret < 0)
+               goto out;
+out:
+       return ret;
+}
+
+static const struct rtc_class_ops max8925_rtc_ops = {
+       .read_time      = max8925_rtc_read_time,
+       .set_time       = max8925_rtc_set_time,
+       .read_alarm     = max8925_rtc_read_alarm,
+       .set_alarm      = max8925_rtc_set_alarm,
+};
+
+static int __devinit max8925_rtc_probe(struct platform_device *pdev)
+{
+       struct max8925_chip *chip = dev_get_drvdata(pdev->dev.parent);
+       struct max8925_rtc_info *info;
+       int irq, ret;
+
+       info = kzalloc(sizeof(struct max8925_rtc_info), GFP_KERNEL);
+       if (!info)
+               return -ENOMEM;
+       info->chip = chip;
+       info->rtc = chip->rtc;
+       info->dev = &pdev->dev;
+       irq = chip->irq_base + MAX8925_IRQ_RTC_ALARM0;
+
+       ret = request_threaded_irq(irq, NULL, rtc_update_handler,
+                                  IRQF_ONESHOT, "rtc-alarm0", info);
+       if (ret < 0) {
+               dev_err(chip->dev, "Failed to request IRQ: #%d: %d\n",
+                       irq, ret);
+               goto out_irq;
+       }
+
+       info->rtc_dev = rtc_device_register("max8925-rtc", &pdev->dev,
+                                       &max8925_rtc_ops, THIS_MODULE);
+       ret = PTR_ERR(info->rtc_dev);
+       if (IS_ERR(info->rtc_dev)) {
+               dev_err(&pdev->dev, "Failed to register RTC device: %d\n", ret);
+               goto out_rtc;
+       }
+
+       dev_set_drvdata(&pdev->dev, info);
+       platform_set_drvdata(pdev, info);
+
+       return 0;
+out_rtc:
+       free_irq(chip->irq_base + MAX8925_IRQ_RTC_ALARM0, info);
+out_irq:
+       kfree(info);
+       return ret;
+}
+
+static int __devexit max8925_rtc_remove(struct platform_device *pdev)
+{
+       struct max8925_rtc_info *info = platform_get_drvdata(pdev);
+
+       if (info) {
+               free_irq(info->chip->irq_base + MAX8925_IRQ_RTC_ALARM0, info);
+               rtc_device_unregister(info->rtc_dev);
+               kfree(info);
+       }
+       return 0;
+}
+
+static struct platform_driver max8925_rtc_driver = {
+       .driver         = {
+               .name   = "max8925-rtc",
+               .owner  = THIS_MODULE,
+       },
+       .probe          = max8925_rtc_probe,
+       .remove         = __devexit_p(max8925_rtc_remove),
+};
+
+static int __init max8925_rtc_init(void)
+{
+       return platform_driver_register(&max8925_rtc_driver);
+}
+module_init(max8925_rtc_init);
+
+static void __exit max8925_rtc_exit(void)
+{
+       platform_driver_unregister(&max8925_rtc_driver);
+}
+module_exit(max8925_rtc_exit);
+
+MODULE_DESCRIPTION("Maxim MAX8925 RTC driver");
+MODULE_AUTHOR("Haojian Zhuang <haojian.zhuang@marvell.com>");
+MODULE_LICENSE("GPL");
+