1 files changed, 514 insertions, 0 deletions

diff --git a/drivers/rtc/rtc-wm8350.c b/drivers/rtc/rtc-wm8350.c
new file mode 100644
index 0000000..5c5e3aa
--- /dev/null
+++ b/drivers/rtc/rtc-wm8350.c
@@ -0,0 +1,514 @@
+/*
+ *	Real Time Clock driver for Wolfson Microelectronics WM8350
+ *
+ *	Copyright (C) 2007, 2008 Wolfson Microelectronics PLC.
+ *
+ *  Author: Liam Girdwood
+ *          linux@wolfsonmicro.com
+ *
+ *  This program is free software; you can redistribute  it and/or modify it
+ *  under  the terms of  the GNU General  Public License as published by the
+ *  Free Software Foundation;  either version 2 of the  License, or (at your
+ *  option) any later version.
+ *
+ */
+
+#include <linux/module.h>
+#include <linux/kernel.h>
+#include <linux/time.h>
+#include <linux/rtc.h>
+#include <linux/bcd.h>
+#include <linux/interrupt.h>
+#include <linux/ioctl.h>
+#include <linux/completion.h>
+#include <linux/mfd/wm8350/rtc.h>
+#include <linux/mfd/wm8350/core.h>
+#include <linux/delay.h>
+#include <linux/platform_device.h>
+
+#define WM8350_SET_ALM_RETRIES	5
+#define WM8350_SET_TIME_RETRIES	5
+#define WM8350_GET_TIME_RETRIES	5
+
+#define to_wm8350_from_rtc_dev(d) container_of(d, struct wm8350, rtc.pdev.dev)
+
+/*
+ * Read current time and date in RTC
+ */
+static int wm8350_rtc_readtime(struct device *dev, struct rtc_time *tm)
+{
+	struct wm8350 *wm8350 = dev_get_drvdata(dev);
+	u16 time1[4], time2[4];
+	int retries = WM8350_GET_TIME_RETRIES, ret;
+
+	/*
+	 * Read the time twice and compare.
+	 * If time1 == time2, then time is valid else retry.
+	 */
+	do {
+		ret = wm8350_block_read(wm8350, WM8350_RTC_SECONDS_MINUTES,
+					4, time1);
+		if (ret < 0)
+			return ret;
+		ret = wm8350_block_read(wm8350, WM8350_RTC_SECONDS_MINUTES,
+					4, time2);
+		if (ret < 0)
+			return ret;
+
+		if (memcmp(time1, time2, sizeof(time1)) == 0) {
+			tm->tm_sec = time1[0] & WM8350_RTC_SECS_MASK;
+
+			tm->tm_min = (time1[0] & WM8350_RTC_MINS_MASK)
+			    >> WM8350_RTC_MINS_SHIFT;
+
+			tm->tm_hour = time1[1] & WM8350_RTC_HRS_MASK;
+
+			tm->tm_wday = ((time1[1] >> WM8350_RTC_DAY_SHIFT)
+				       & 0x7) - 1;
+
+			tm->tm_mon = ((time1[2] & WM8350_RTC_MTH_MASK)
+				      >> WM8350_RTC_MTH_SHIFT) - 1;
+
+			tm->tm_mday = (time1[2] & WM8350_RTC_DATE_MASK);
+
+			tm->tm_year = ((time1[3] & WM8350_RTC_YHUNDREDS_MASK)
+				       >> WM8350_RTC_YHUNDREDS_SHIFT) * 100;
+			tm->tm_year += time1[3] & WM8350_RTC_YUNITS_MASK;
+
+			tm->tm_yday = rtc_year_days(tm->tm_mday, tm->tm_mon,
+						    tm->tm_year);
+			tm->tm_year -= 1900;
+
+			dev_dbg(dev, "Read (%d left): %04x %04x %04x %04x\n",
+				retries,
+				time1[0], time1[1], time1[2], time1[3]);
+
+			return 0;
+		}
+	} while (retries--);
+
+	dev_err(dev, "timed out reading RTC time\n");
+	return -EIO;
+}
+
+/*
+ * Set current time and date in RTC
+ */
+static int wm8350_rtc_settime(struct device *dev, struct rtc_time *tm)
+{
+	struct wm8350 *wm8350 = dev_get_drvdata(dev);
+	u16 time[4];
+	u16 rtc_ctrl;
+	int ret, retries = WM8350_SET_TIME_RETRIES;
+
+	time[0] = tm->tm_sec;
+	time[0] |= tm->tm_min << WM8350_RTC_MINS_SHIFT;
+	time[1] = tm->tm_hour;
+	time[1] |= (tm->tm_wday + 1) << WM8350_RTC_DAY_SHIFT;
+	time[2] = tm->tm_mday;
+	time[2] |= (tm->tm_mon + 1) << WM8350_RTC_MTH_SHIFT;
+	time[3] = ((tm->tm_year + 1900) / 100) << WM8350_RTC_YHUNDREDS_SHIFT;
+	time[3] |= (tm->tm_year + 1900) % 100;
+
+	dev_dbg(dev, "Setting: %04x %04x %04x %04x\n",
+		time[0], time[1], time[2], time[3]);
+
+	/* Set RTC_SET to stop the clock */
+	ret = wm8350_set_bits(wm8350, WM8350_RTC_TIME_CONTROL, WM8350_RTC_SET);
+	if (ret < 0)
+		return ret;
+
+	/* Wait until confirmation of stopping */
+	do {
+		rtc_ctrl = wm8350_reg_read(wm8350, WM8350_RTC_TIME_CONTROL);
+		schedule_timeout_uninterruptible(msecs_to_jiffies(1));
+	} while (retries-- && !(rtc_ctrl & WM8350_RTC_STS));
+
+	if (!retries) {
+		dev_err(dev, "timed out on set confirmation\n");
+		return -EIO;
+	}
+
+	/* Write time to RTC */
+	ret = wm8350_block_write(wm8350, WM8350_RTC_SECONDS_MINUTES, 4, time);
+	if (ret < 0)
+		return ret;
+
+	/* Clear RTC_SET to start the clock */
+	ret = wm8350_clear_bits(wm8350, WM8350_RTC_TIME_CONTROL,
+				WM8350_RTC_SET);
+	return ret;
+}
+
+/*
+ * Read alarm time and date in RTC
+ */
+static int wm8350_rtc_readalarm(struct device *dev, struct rtc_wkalrm *alrm)
+{
+	struct wm8350 *wm8350 = dev_get_drvdata(dev);
+	struct rtc_time *tm = &alrm->time;
+	u16 time[4];
+	int ret;
+
+	ret = wm8350_block_read(wm8350, WM8350_ALARM_SECONDS_MINUTES, 4, time);
+	if (ret < 0)
+		return ret;
+
+	tm->tm_sec = time[0] & WM8350_RTC_ALMSECS_MASK;
+	if (tm->tm_sec == WM8350_RTC_ALMSECS_MASK)
+		tm->tm_sec = -1;
+
+	tm->tm_min = time[0] & WM8350_RTC_ALMMINS_MASK;
+	if (tm->tm_min == WM8350_RTC_ALMMINS_MASK)
+		tm->tm_min = -1;
+	else
+		tm->tm_min >>= WM8350_RTC_ALMMINS_SHIFT;
+
+	tm->tm_hour = time[1] & WM8350_RTC_ALMHRS_MASK;
+	if (tm->tm_hour == WM8350_RTC_ALMHRS_MASK)
+		tm->tm_hour = -1;
+
+	tm->tm_wday = ((time[1] >> WM8350_RTC_ALMDAY_SHIFT) & 0x7) - 1;
+	if (tm->tm_wday > 7)
+		tm->tm_wday = -1;
+
+	tm->tm_mon = time[2] & WM8350_RTC_ALMMTH_MASK;
+	if (tm->tm_mon == WM8350_RTC_ALMMTH_MASK)
+		tm->tm_mon = -1;
+	else
+		tm->tm_mon = (tm->tm_mon >> WM8350_RTC_ALMMTH_SHIFT) - 1;
+
+	tm->tm_mday = (time[2] & WM8350_RTC_ALMDATE_MASK);
+	if (tm->tm_mday == WM8350_RTC_ALMDATE_MASK)
+		tm->tm_mday = -1;
+
+	tm->tm_year = -1;
+
+	alrm->enabled = !(time[3] & WM8350_RTC_ALMSTS);
+
+	return 0;
+}
+
+static int wm8350_rtc_stop_alarm(struct wm8350 *wm8350)
+{
+	int retries = WM8350_SET_ALM_RETRIES;
+	u16 rtc_ctrl;
+	int ret;
+
+	/* Set RTC_SET to stop the clock */
+	ret = wm8350_set_bits(wm8350, WM8350_RTC_TIME_CONTROL,
+			      WM8350_RTC_ALMSET);
+	if (ret < 0)
+		return ret;
+
+	/* Wait until confirmation of stopping */
+	do {
+		rtc_ctrl = wm8350_reg_read(wm8350, WM8350_RTC_TIME_CONTROL);
+		schedule_timeout_uninterruptible(msecs_to_jiffies(1));
+	} while (retries-- && !(rtc_ctrl & WM8350_RTC_ALMSTS));
+
+	if (!(rtc_ctrl & WM8350_RTC_ALMSTS))
+		return -ETIMEDOUT;
+
+	return 0;
+}
+
+static int wm8350_rtc_start_alarm(struct wm8350 *wm8350)
+{
+	int ret;
+	int retries = WM8350_SET_ALM_RETRIES;
+	u16 rtc_ctrl;
+
+	ret = wm8350_clear_bits(wm8350, WM8350_RTC_TIME_CONTROL,
+				WM8350_RTC_ALMSET);
+	if (ret < 0)
+		return ret;
+
+	/* Wait until confirmation */
+	do {
+		rtc_ctrl = wm8350_reg_read(wm8350, WM8350_RTC_TIME_CONTROL);
+		schedule_timeout_uninterruptible(msecs_to_jiffies(1));
+	} while (retries-- && rtc_ctrl & WM8350_RTC_ALMSTS);
+
+	if (rtc_ctrl & WM8350_RTC_ALMSTS)
+		return -ETIMEDOUT;
+
+	return 0;
+}
+
+static int wm8350_rtc_setalarm(struct device *dev, struct rtc_wkalrm *alrm)
+{
+	struct wm8350 *wm8350 = dev_get_drvdata(dev);
+	struct rtc_time *tm = &alrm->time;
+	u16 time[3];
+	int ret;
+
+	memset(time, 0, sizeof(time));
+
+	if (tm->tm_sec != -1)
+		time[0] |= tm->tm_sec;
+	else
+		time[0] |= WM8350_RTC_ALMSECS_MASK;
+
+	if (tm->tm_min != -1)
+		time[0] |= tm->tm_min << WM8350_RTC_ALMMINS_SHIFT;
+	else
+		time[0] |= WM8350_RTC_ALMMINS_MASK;
+
+	if (tm->tm_hour != -1)
+		time[1] |= tm->tm_hour;
+	else
+		time[1] |= WM8350_RTC_ALMHRS_MASK;
+
+	if (tm->tm_wday != -1)
+		time[1] |= (tm->tm_wday + 1) << WM8350_RTC_ALMDAY_SHIFT;
+	else
+		time[1] |= WM8350_RTC_ALMDAY_MASK;
+
+	if (tm->tm_mday != -1)
+		time[2] |= tm->tm_mday;
+	else
+		time[2] |= WM8350_RTC_ALMDATE_MASK;
+
+	if (tm->tm_mon != -1)
+		time[2] |= (tm->tm_mon + 1) << WM8350_RTC_ALMMTH_SHIFT;
+	else
+		time[2] |= WM8350_RTC_ALMMTH_MASK;
+
+	ret = wm8350_rtc_stop_alarm(wm8350);
+	if (ret < 0)
+		return ret;
+
+	/* Write time to RTC */
+	ret = wm8350_block_write(wm8350, WM8350_ALARM_SECONDS_MINUTES,
+				 3, time);
+	if (ret < 0)
+		return ret;
+
+	if (alrm->enabled)
+		ret = wm8350_rtc_start_alarm(wm8350);
+
+	return ret;
+}
+
+/*
+ * Handle commands from user-space
+ */
+static int wm8350_rtc_ioctl(struct device *dev, unsigned int cmd,
+			    unsigned long arg)
+{
+	struct wm8350 *wm8350 = dev_get_drvdata(dev);
+
+	switch (cmd) {
+	case RTC_AIE_OFF:
+		return wm8350_rtc_stop_alarm(wm8350);
+	case RTC_AIE_ON:
+		return wm8350_rtc_start_alarm(wm8350);
+
+	case RTC_UIE_OFF:
+		wm8350_mask_irq(wm8350, WM8350_IRQ_RTC_SEC);
+		break;
+	case RTC_UIE_ON:
+		wm8350_unmask_irq(wm8350, WM8350_IRQ_RTC_SEC);
+		break;
+
+	default:
+		return -ENOIOCTLCMD;
+	}
+
+	return 0;
+}
+
+static void wm8350_rtc_alarm_handler(struct wm8350 *wm8350, int irq,
+				     void *data)
+{
+	struct rtc_device *rtc = wm8350->rtc.rtc;
+	int ret;
+
+	rtc_update_irq(rtc, 1, RTC_IRQF | RTC_AF);
+
+	/* Make it one shot */
+	ret = wm8350_set_bits(wm8350, WM8350_RTC_TIME_CONTROL,
+			      WM8350_RTC_ALMSET);
+	if (ret != 0) {
+		dev_err(&(wm8350->rtc.pdev->dev),
+			"Failed to disable alarm: %d\n", ret);
+	}
+}
+
+static void wm8350_rtc_update_handler(struct wm8350 *wm8350, int irq,
+				      void *data)
+{
+	struct rtc_device *rtc = wm8350->rtc.rtc;
+
+	rtc_update_irq(rtc, 1, RTC_IRQF | RTC_UF);
+}
+
+static const struct rtc_class_ops wm8350_rtc_ops = {
+	.ioctl = wm8350_rtc_ioctl,
+	.read_time = wm8350_rtc_readtime,
+	.set_time = wm8350_rtc_settime,
+	.read_alarm = wm8350_rtc_readalarm,
+	.set_alarm = wm8350_rtc_setalarm,
+};
+
+#ifdef CONFIG_PM
+static int wm8350_rtc_suspend(struct platform_device *pdev, pm_message_t state)
+{
+	struct wm8350 *wm8350 = dev_get_drvdata(&pdev->dev);
+	int ret = 0;
+	u16 reg;
+
+	reg = wm8350_reg_read(wm8350, WM8350_RTC_TIME_CONTROL);
+
+	if (device_may_wakeup(&wm8350->rtc.pdev->dev) &&
+	    reg & WM8350_RTC_ALMSTS) {
+		ret = wm8350_rtc_stop_alarm(wm8350);
+		if (ret != 0)
+			dev_err(&pdev->dev, "Failed to stop RTC alarm: %d\n",
+				ret);
+	}
+
+	return ret;
+}
+
+static int wm8350_rtc_resume(struct platform_device *pdev)
+{
+	struct wm8350 *wm8350 = dev_get_drvdata(&pdev->dev);
+	int ret;
+
+	if (wm8350->rtc.alarm_enabled) {
+		ret = wm8350_rtc_start_alarm(wm8350);
+		if (ret != 0)
+			dev_err(&pdev->dev,
+				"Failed to restart RTC alarm: %d\n", ret);
+	}
+
+	return 0;
+}
+
+#else
+#define wm8350_rtc_suspend NULL
+#define wm8350_rtc_resume NULL
+#endif
+
+static int wm8350_rtc_probe(struct platform_device *pdev)
+{
+	struct wm8350 *wm8350 = platform_get_drvdata(pdev);
+	struct wm8350_rtc *wm_rtc = &wm8350->rtc;
+	int ret = 0;
+	u16 timectl, power5;
+
+	timectl = wm8350_reg_read(wm8350, WM8350_RTC_TIME_CONTROL);
+	if (timectl & WM8350_RTC_BCD) {
+		dev_err(&pdev->dev, "RTC BCD mode not supported\n");
+		return -EINVAL;
+	}
+	if (timectl & WM8350_RTC_12HR) {
+		dev_err(&pdev->dev, "RTC 12 hour mode not supported\n");
+		return -EINVAL;
+	}
+
+	/* enable the RTC if it's not already enabled */
+	power5 = wm8350_reg_read(wm8350, WM8350_POWER_MGMT_5);
+	if (!(power5 &  WM8350_RTC_TICK_ENA)) {
+		dev_info(wm8350->dev, "Starting RTC\n");
+
+		wm8350_reg_unlock(wm8350);
+
+		ret = wm8350_set_bits(wm8350, WM8350_POWER_MGMT_5,
+				      WM8350_RTC_TICK_ENA);
+		if (ret < 0) {
+			dev_err(&pdev->dev, "failed to enable RTC: %d\n", ret);
+			return ret;
+		}
+
+		wm8350_reg_lock(wm8350);
+	}
+
+	if (timectl & WM8350_RTC_STS) {
+		int retries;
+
+		ret = wm8350_clear_bits(wm8350, WM8350_RTC_TIME_CONTROL,
+					WM8350_RTC_SET);
+		if (ret < 0) {
+			dev_err(&pdev->dev, "failed to start: %d\n", ret);
+			return ret;
+		}
+
+		retries = WM8350_SET_TIME_RETRIES;
+		do {
+			timectl = wm8350_reg_read(wm8350,
+						  WM8350_RTC_TIME_CONTROL);
+		} while (timectl & WM8350_RTC_STS && retries--);
+
+		if (retries == 0) {
+			dev_err(&pdev->dev, "failed to start: timeout\n");
+			return -ENODEV;
+		}
+	}
+
+	device_init_wakeup(&pdev->dev, 1);
+
+	wm_rtc->rtc = rtc_device_register("wm8350", &pdev->dev,
+					  &wm8350_rtc_ops, THIS_MODULE);
+	if (IS_ERR(wm_rtc->rtc)) {
+		ret = PTR_ERR(wm_rtc->rtc);
+		dev_err(&pdev->dev, "failed to register RTC: %d\n", ret);
+		return ret;
+	}
+
+	wm8350_mask_irq(wm8350, WM8350_IRQ_RTC_SEC);
+	wm8350_mask_irq(wm8350, WM8350_IRQ_RTC_PER);
+
+	wm8350_register_irq(wm8350, WM8350_IRQ_RTC_SEC,
+			    wm8350_rtc_update_handler, NULL);
+
+	wm8350_register_irq(wm8350, WM8350_IRQ_RTC_ALM,
+			    wm8350_rtc_alarm_handler, NULL);
+	wm8350_unmask_irq(wm8350, WM8350_IRQ_RTC_ALM);
+
+	return 0;
+}
+
+static int __devexit wm8350_rtc_remove(struct platform_device *pdev)
+{
+	struct wm8350 *wm8350 = platform_get_drvdata(pdev);
+	struct wm8350_rtc *wm_rtc = &wm8350->rtc;
+
+	wm8350_mask_irq(wm8350, WM8350_IRQ_RTC_SEC);
+
+	wm8350_free_irq(wm8350, WM8350_IRQ_RTC_SEC);
+	wm8350_free_irq(wm8350, WM8350_IRQ_RTC_ALM);
+
+	rtc_device_unregister(wm_rtc->rtc);
+
+	return 0;
+}
+
+static struct platform_driver wm8350_rtc_driver = {
+	.probe = wm8350_rtc_probe,
+	.remove = __devexit_p(wm8350_rtc_remove),
+	.suspend = wm8350_rtc_suspend,
+	.resume = wm8350_rtc_resume,
+	.driver = {
+		.name = "wm8350-rtc",
+	},
+};
+
+static int __init wm8350_rtc_init(void)
+{
+	return platform_driver_register(&wm8350_rtc_driver);
+}
+module_init(wm8350_rtc_init);
+
+static void __exit wm8350_rtc_exit(void)
+{
+	platform_driver_unregister(&wm8350_rtc_driver);
+}
+module_exit(wm8350_rtc_exit);
+
+MODULE_AUTHOR("Mark Brown <broonie@opensource.wolfsonmicro.com>");
+MODULE_DESCRIPTION("RTC driver for the WM8350");
+MODULE_LICENSE("GPL");
+MODULE_ALIAS("platform:wm8350-rtc");