--- /dev/null
+/*
+ * TI LP8788 MFD - rtc driver
+ *
+ * Copyright 2012 Texas Instruments
+ *
+ * Author: Milo(Woogyom) Kim <milo.kim@ti.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/err.h>
+#include <linux/irqdomain.h>
+#include <linux/mfd/lp8788.h>
+#include <linux/module.h>
+#include <linux/platform_device.h>
+#include <linux/rtc.h>
+#include <linux/slab.h>
+
+/* register address */
+#define LP8788_INTEN_3 0x05
+#define LP8788_RTC_UNLOCK 0x64
+#define LP8788_RTC_SEC 0x70
+#define LP8788_ALM1_SEC 0x77
+#define LP8788_ALM1_EN 0x7D
+#define LP8788_ALM2_SEC 0x7E
+#define LP8788_ALM2_EN 0x84
+
+/* mask/shift bits */
+#define LP8788_INT_RTC_ALM1_M BIT(1) /* Addr 05h */
+#define LP8788_INT_RTC_ALM1_S 1
+#define LP8788_INT_RTC_ALM2_M BIT(2) /* Addr 05h */
+#define LP8788_INT_RTC_ALM2_S 2
+#define LP8788_ALM_EN_M BIT(7) /* Addr 7Dh or 84h */
+#define LP8788_ALM_EN_S 7
+
+#define DEFAULT_ALARM_SEL LP8788_ALARM_1
+#define LP8788_MONTH_OFFSET 1
+#define LP8788_BASE_YEAR 2000
+#define MAX_WDAY_BITS 7
+#define LP8788_WDAY_SET 1
+#define RTC_UNLOCK 0x1
+#define RTC_LATCH 0x2
+#define ALARM_IRQ_FLAG (RTC_IRQF | RTC_AF)
+
+enum lp8788_time {
+ LPTIME_SEC,
+ LPTIME_MIN,
+ LPTIME_HOUR,
+ LPTIME_MDAY,
+ LPTIME_MON,
+ LPTIME_YEAR,
+ LPTIME_WDAY,
+ LPTIME_MAX,
+};
+
+struct lp8788_rtc {
+ struct lp8788 *lp;
+ struct rtc_device *rdev;
+ enum lp8788_alarm_sel alarm;
+ int irq;
+};
+
+static const u8 addr_alarm_sec[LP8788_ALARM_MAX] = {
+ LP8788_ALM1_SEC,
+ LP8788_ALM2_SEC,
+};
+
+static const u8 addr_alarm_en[LP8788_ALARM_MAX] = {
+ LP8788_ALM1_EN,
+ LP8788_ALM2_EN,
+};
+
+static const u8 mask_alarm_en[LP8788_ALARM_MAX] = {
+ LP8788_INT_RTC_ALM1_M,
+ LP8788_INT_RTC_ALM2_M,
+};
+
+static const u8 shift_alarm_en[LP8788_ALARM_MAX] = {
+ LP8788_INT_RTC_ALM1_S,
+ LP8788_INT_RTC_ALM2_S,
+};
+
+static int _to_tm_wday(u8 lp8788_wday)
+{
+ int i;
+
+ if (lp8788_wday == 0)
+ return 0;
+
+ /* lookup defined weekday from read register value */
+ for (i = 0; i < MAX_WDAY_BITS; i++) {
+ if ((lp8788_wday >> i) == LP8788_WDAY_SET)
+ break;
+ }
+
+ return i + 1;
+}
+
+static inline int _to_lp8788_wday(int tm_wday)
+{
+ return LP8788_WDAY_SET << (tm_wday - 1);
+}
+
+static void lp8788_rtc_unlock(struct lp8788 *lp)
+{
+ lp8788_write_byte(lp, LP8788_RTC_UNLOCK, RTC_UNLOCK);
+ lp8788_write_byte(lp, LP8788_RTC_UNLOCK, RTC_LATCH);
+}
+
+static int lp8788_rtc_read_time(struct device *dev, struct rtc_time *tm)
+{
+ struct lp8788_rtc *rtc = dev_get_drvdata(dev);
+ struct lp8788 *lp = rtc->lp;
+ u8 data[LPTIME_MAX];
+ int ret;
+
+ lp8788_rtc_unlock(lp);
+
+ ret = lp8788_read_multi_bytes(lp, LP8788_RTC_SEC, data, LPTIME_MAX);
+ if (ret)
+ return ret;
+
+ tm->tm_sec = data[LPTIME_SEC];
+ tm->tm_min = data[LPTIME_MIN];
+ tm->tm_hour = data[LPTIME_HOUR];
+ tm->tm_mday = data[LPTIME_MDAY];
+ tm->tm_mon = data[LPTIME_MON] - LP8788_MONTH_OFFSET;
+ tm->tm_year = data[LPTIME_YEAR] + LP8788_BASE_YEAR - 1900;
+ tm->tm_wday = _to_tm_wday(data[LPTIME_WDAY]);
+
+ return 0;
+}
+
+static int lp8788_rtc_set_time(struct device *dev, struct rtc_time *tm)
+{
+ struct lp8788_rtc *rtc = dev_get_drvdata(dev);
+ struct lp8788 *lp = rtc->lp;
+ u8 data[LPTIME_MAX - 1];
+ int ret, i, year;
+
+ year = tm->tm_year + 1900 - LP8788_BASE_YEAR;
+ if (year < 0) {
+ dev_err(lp->dev, "invalid year: %d\n", year);
+ return -EINVAL;
+ }
+
+ /* because rtc weekday is a readonly register, do not update */
+ data[LPTIME_SEC] = tm->tm_sec;
+ data[LPTIME_MIN] = tm->tm_min;
+ data[LPTIME_HOUR] = tm->tm_hour;
+ data[LPTIME_MDAY] = tm->tm_mday;
+ data[LPTIME_MON] = tm->tm_mon + LP8788_MONTH_OFFSET;
+ data[LPTIME_YEAR] = year;
+
+ for (i = 0; i < ARRAY_SIZE(data); i++) {
+ ret = lp8788_write_byte(lp, LP8788_RTC_SEC + i, data[i]);
+ if (ret)
+ return ret;
+ }
+
+ return 0;
+}
+
+static int lp8788_read_alarm(struct device *dev, struct rtc_wkalrm *alarm)
+{
+ struct lp8788_rtc *rtc = dev_get_drvdata(dev);
+ struct lp8788 *lp = rtc->lp;
+ struct rtc_time *tm = &alarm->time;
+ u8 addr, data[LPTIME_MAX];
+ int ret;
+
+ addr = addr_alarm_sec[rtc->alarm];
+ ret = lp8788_read_multi_bytes(lp, addr, data, LPTIME_MAX);
+ if (ret)
+ return ret;
+
+ tm->tm_sec = data[LPTIME_SEC];
+ tm->tm_min = data[LPTIME_MIN];
+ tm->tm_hour = data[LPTIME_HOUR];
+ tm->tm_mday = data[LPTIME_MDAY];
+ tm->tm_mon = data[LPTIME_MON] - LP8788_MONTH_OFFSET;
+ tm->tm_year = data[LPTIME_YEAR] + LP8788_BASE_YEAR - 1900;
+ tm->tm_wday = _to_tm_wday(data[LPTIME_WDAY]);
+ alarm->enabled = data[LPTIME_WDAY] & LP8788_ALM_EN_M;
+
+ return 0;
+}
+
+static int lp8788_set_alarm(struct device *dev, struct rtc_wkalrm *alarm)
+{
+ struct lp8788_rtc *rtc = dev_get_drvdata(dev);
+ struct lp8788 *lp = rtc->lp;
+ struct rtc_time *tm = &alarm->time;
+ u8 addr, data[LPTIME_MAX];
+ int ret, i, year;
+
+ year = tm->tm_year + 1900 - LP8788_BASE_YEAR;
+ if (year < 0) {
+ dev_err(lp->dev, "invalid year: %d\n", year);
+ return -EINVAL;
+ }
+
+ data[LPTIME_SEC] = tm->tm_sec;
+ data[LPTIME_MIN] = tm->tm_min;
+ data[LPTIME_HOUR] = tm->tm_hour;
+ data[LPTIME_MDAY] = tm->tm_mday;
+ data[LPTIME_MON] = tm->tm_mon + LP8788_MONTH_OFFSET;
+ data[LPTIME_YEAR] = year;
+ data[LPTIME_WDAY] = _to_lp8788_wday(tm->tm_wday);
+
+ for (i = 0; i < ARRAY_SIZE(data); i++) {
+ addr = addr_alarm_sec[rtc->alarm] + i;
+ ret = lp8788_write_byte(lp, addr, data[i]);
+ if (ret)
+ return ret;
+ }
+
+ alarm->enabled = 1;
+ addr = addr_alarm_en[rtc->alarm];
+
+ return lp8788_update_bits(lp, addr, LP8788_ALM_EN_M,
+ alarm->enabled << LP8788_ALM_EN_S);
+}
+
+static int lp8788_alarm_irq_enable(struct device *dev, unsigned int enable)
+{
+ struct lp8788_rtc *rtc = dev_get_drvdata(dev);
+ struct lp8788 *lp = rtc->lp;
+ u8 mask, shift;
+
+ if (!rtc->irq)
+ return -EIO;
+
+ mask = mask_alarm_en[rtc->alarm];
+ shift = shift_alarm_en[rtc->alarm];
+
+ return lp8788_update_bits(lp, LP8788_INTEN_3, mask, enable << shift);
+}
+
+static const struct rtc_class_ops lp8788_rtc_ops = {
+ .read_time = lp8788_rtc_read_time,
+ .set_time = lp8788_rtc_set_time,
+ .read_alarm = lp8788_read_alarm,
+ .set_alarm = lp8788_set_alarm,
+ .alarm_irq_enable = lp8788_alarm_irq_enable,
+};
+
+static irqreturn_t lp8788_alarm_irq_handler(int irq, void *ptr)
+{
+ struct lp8788_rtc *rtc = ptr;
+
+ rtc_update_irq(rtc->rdev, 1, ALARM_IRQ_FLAG);
+ return IRQ_HANDLED;
+}
+
+static int lp8788_alarm_irq_register(struct platform_device *pdev,
+ struct lp8788_rtc *rtc)
+{
+ struct resource *r;
+ struct lp8788 *lp = rtc->lp;
+ struct irq_domain *irqdm = lp->irqdm;
+ int irq;
+
+ rtc->irq = 0;
+
+ /* even the alarm IRQ number is not specified, rtc time should work */
+ r = platform_get_resource_byname(pdev, IORESOURCE_IRQ, LP8788_ALM_IRQ);
+ if (!r)
+ return 0;
+
+ if (rtc->alarm == LP8788_ALARM_1)
+ irq = r->start;
+ else
+ irq = r->end;
+
+ rtc->irq = irq_create_mapping(irqdm, irq);
+
+ return request_threaded_irq(rtc->irq, NULL, lp8788_alarm_irq_handler,
+ 0, LP8788_ALM_IRQ, rtc);
+}
+
+static void lp8788_alarm_irq_unregister(struct lp8788_rtc *rtc)
+{
+ if (rtc->irq)
+ free_irq(rtc->irq, rtc);
+}
+
+static int lp8788_rtc_probe(struct platform_device *pdev)
+{
+ struct lp8788 *lp = dev_get_drvdata(pdev->dev.parent);
+ struct lp8788_rtc *rtc;
+ struct device *dev = &pdev->dev;
+
+ rtc = devm_kzalloc(dev, sizeof(struct lp8788_rtc), GFP_KERNEL);
+ if (!rtc)
+ return -ENOMEM;
+
+ rtc->lp = lp;
+ rtc->alarm = lp->pdata ? lp->pdata->alarm_sel : DEFAULT_ALARM_SEL;
+ platform_set_drvdata(pdev, rtc);
+
+ device_init_wakeup(dev, 1);
+
+ rtc->rdev = rtc_device_register("lp8788_rtc", dev,
+ &lp8788_rtc_ops, THIS_MODULE);
+ if (IS_ERR(rtc->rdev)) {
+ dev_err(dev, "can not register rtc device\n");
+ return PTR_ERR(rtc->rdev);
+ }
+
+ if (lp8788_alarm_irq_register(pdev, rtc))
+ dev_warn(lp->dev, "no rtc irq handler\n");
+
+ return 0;
+}
+
+static int lp8788_rtc_remove(struct platform_device *pdev)
+{
+ struct lp8788_rtc *rtc = platform_get_drvdata(pdev);
+
+ lp8788_alarm_irq_unregister(rtc);
+ rtc_device_unregister(rtc->rdev);
+ platform_set_drvdata(pdev, NULL);
+
+ return 0;
+}
+
+static struct platform_driver lp8788_rtc_driver = {
+ .probe = lp8788_rtc_probe,
+ .remove = lp8788_rtc_remove,
+ .driver = {
+ .name = LP8788_DEV_RTC,
+ .owner = THIS_MODULE,
+ },
+};
+module_platform_driver(lp8788_rtc_driver);
+
+MODULE_DESCRIPTION("Texas Instruments LP8788 RTC Driver");
+MODULE_AUTHOR("Milo Kim");
+MODULE_LICENSE("GPL");
+MODULE_ALIAS("platform:lp8788-rtc");
projects / platform / kernel / linux-stable.git / commitdiff