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authorYunhong Jiang <yunhong.jiang@intel.com>2015-08-04 12:17:53 -0700
committerYunhong Jiang <yunhong.jiang@intel.com>2015-08-04 15:44:42 -0700
commit9ca8dbcc65cfc63d6f5ef3312a33184e1d726e00 (patch)
tree1c9cafbcd35f783a87880a10f85d1a060db1a563 /kernel/drivers/rtc/rtc-omap.c
parent98260f3884f4a202f9ca5eabed40b1354c489b29 (diff)
Add the rt linux 4.1.3-rt3 as base
Import the rt linux 4.1.3-rt3 as OPNFV kvm base. It's from git://git.kernel.org/pub/scm/linux/kernel/git/rt/linux-rt-devel.git linux-4.1.y-rt and the base is: commit 0917f823c59692d751951bf5ea699a2d1e2f26a2 Author: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Date: Sat Jul 25 12:13:34 2015 +0200 Prepare v4.1.3-rt3 Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> We lose all the git history this way and it's not good. We should apply another opnfv project repo in future. Change-Id: I87543d81c9df70d99c5001fbdf646b202c19f423 Signed-off-by: Yunhong Jiang <yunhong.jiang@intel.com>
Diffstat (limited to 'kernel/drivers/rtc/rtc-omap.c')
-rw-r--r--kernel/drivers/rtc/rtc-omap.c774
1 files changed, 774 insertions, 0 deletions
diff --git a/kernel/drivers/rtc/rtc-omap.c b/kernel/drivers/rtc/rtc-omap.c
new file mode 100644
index 000000000..8b6355ffa
--- /dev/null
+++ b/kernel/drivers/rtc/rtc-omap.c
@@ -0,0 +1,774 @@
+/*
+ * TI OMAP Real Time Clock interface for Linux
+ *
+ * Copyright (C) 2003 MontaVista Software, Inc.
+ * Author: George G. Davis <gdavis@mvista.com> or <source@mvista.com>
+ *
+ * Copyright (C) 2006 David Brownell (new RTC framework)
+ * Copyright (C) 2014 Johan Hovold <johan@kernel.org>
+ *
+ * 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/kernel.h>
+#include <linux/init.h>
+#include <linux/module.h>
+#include <linux/ioport.h>
+#include <linux/delay.h>
+#include <linux/rtc.h>
+#include <linux/bcd.h>
+#include <linux/platform_device.h>
+#include <linux/of.h>
+#include <linux/of_device.h>
+#include <linux/pm_runtime.h>
+#include <linux/io.h>
+
+/*
+ * The OMAP RTC is a year/month/day/hours/minutes/seconds BCD clock
+ * with century-range alarm matching, driven by the 32kHz clock.
+ *
+ * The main user-visible ways it differs from PC RTCs are by omitting
+ * "don't care" alarm fields and sub-second periodic IRQs, and having
+ * an autoadjust mechanism to calibrate to the true oscillator rate.
+ *
+ * Board-specific wiring options include using split power mode with
+ * RTC_OFF_NOFF used as the reset signal (so the RTC won't be reset),
+ * and wiring RTC_WAKE_INT (so the RTC alarm can wake the system from
+ * low power modes) for OMAP1 boards (OMAP-L138 has this built into
+ * the SoC). See the BOARD-SPECIFIC CUSTOMIZATION comment.
+ */
+
+/* RTC registers */
+#define OMAP_RTC_SECONDS_REG 0x00
+#define OMAP_RTC_MINUTES_REG 0x04
+#define OMAP_RTC_HOURS_REG 0x08
+#define OMAP_RTC_DAYS_REG 0x0C
+#define OMAP_RTC_MONTHS_REG 0x10
+#define OMAP_RTC_YEARS_REG 0x14
+#define OMAP_RTC_WEEKS_REG 0x18
+
+#define OMAP_RTC_ALARM_SECONDS_REG 0x20
+#define OMAP_RTC_ALARM_MINUTES_REG 0x24
+#define OMAP_RTC_ALARM_HOURS_REG 0x28
+#define OMAP_RTC_ALARM_DAYS_REG 0x2c
+#define OMAP_RTC_ALARM_MONTHS_REG 0x30
+#define OMAP_RTC_ALARM_YEARS_REG 0x34
+
+#define OMAP_RTC_CTRL_REG 0x40
+#define OMAP_RTC_STATUS_REG 0x44
+#define OMAP_RTC_INTERRUPTS_REG 0x48
+
+#define OMAP_RTC_COMP_LSB_REG 0x4c
+#define OMAP_RTC_COMP_MSB_REG 0x50
+#define OMAP_RTC_OSC_REG 0x54
+
+#define OMAP_RTC_KICK0_REG 0x6c
+#define OMAP_RTC_KICK1_REG 0x70
+
+#define OMAP_RTC_IRQWAKEEN 0x7c
+
+#define OMAP_RTC_ALARM2_SECONDS_REG 0x80
+#define OMAP_RTC_ALARM2_MINUTES_REG 0x84
+#define OMAP_RTC_ALARM2_HOURS_REG 0x88
+#define OMAP_RTC_ALARM2_DAYS_REG 0x8c
+#define OMAP_RTC_ALARM2_MONTHS_REG 0x90
+#define OMAP_RTC_ALARM2_YEARS_REG 0x94
+
+#define OMAP_RTC_PMIC_REG 0x98
+
+/* OMAP_RTC_CTRL_REG bit fields: */
+#define OMAP_RTC_CTRL_SPLIT BIT(7)
+#define OMAP_RTC_CTRL_DISABLE BIT(6)
+#define OMAP_RTC_CTRL_SET_32_COUNTER BIT(5)
+#define OMAP_RTC_CTRL_TEST BIT(4)
+#define OMAP_RTC_CTRL_MODE_12_24 BIT(3)
+#define OMAP_RTC_CTRL_AUTO_COMP BIT(2)
+#define OMAP_RTC_CTRL_ROUND_30S BIT(1)
+#define OMAP_RTC_CTRL_STOP BIT(0)
+
+/* OMAP_RTC_STATUS_REG bit fields: */
+#define OMAP_RTC_STATUS_POWER_UP BIT(7)
+#define OMAP_RTC_STATUS_ALARM2 BIT(7)
+#define OMAP_RTC_STATUS_ALARM BIT(6)
+#define OMAP_RTC_STATUS_1D_EVENT BIT(5)
+#define OMAP_RTC_STATUS_1H_EVENT BIT(4)
+#define OMAP_RTC_STATUS_1M_EVENT BIT(3)
+#define OMAP_RTC_STATUS_1S_EVENT BIT(2)
+#define OMAP_RTC_STATUS_RUN BIT(1)
+#define OMAP_RTC_STATUS_BUSY BIT(0)
+
+/* OMAP_RTC_INTERRUPTS_REG bit fields: */
+#define OMAP_RTC_INTERRUPTS_IT_ALARM2 BIT(4)
+#define OMAP_RTC_INTERRUPTS_IT_ALARM BIT(3)
+#define OMAP_RTC_INTERRUPTS_IT_TIMER BIT(2)
+
+/* OMAP_RTC_OSC_REG bit fields: */
+#define OMAP_RTC_OSC_32KCLK_EN BIT(6)
+
+/* OMAP_RTC_IRQWAKEEN bit fields: */
+#define OMAP_RTC_IRQWAKEEN_ALARM_WAKEEN BIT(1)
+
+/* OMAP_RTC_PMIC bit fields: */
+#define OMAP_RTC_PMIC_POWER_EN_EN BIT(16)
+
+/* OMAP_RTC_KICKER values */
+#define KICK0_VALUE 0x83e70b13
+#define KICK1_VALUE 0x95a4f1e0
+
+struct omap_rtc;
+
+struct omap_rtc_device_type {
+ bool has_32kclk_en;
+ bool has_irqwakeen;
+ bool has_pmic_mode;
+ bool has_power_up_reset;
+ void (*lock)(struct omap_rtc *rtc);
+ void (*unlock)(struct omap_rtc *rtc);
+};
+
+struct omap_rtc {
+ struct rtc_device *rtc;
+ void __iomem *base;
+ int irq_alarm;
+ int irq_timer;
+ u8 interrupts_reg;
+ bool is_pmic_controller;
+ const struct omap_rtc_device_type *type;
+};
+
+static inline u8 rtc_read(struct omap_rtc *rtc, unsigned int reg)
+{
+ return readb(rtc->base + reg);
+}
+
+static inline u32 rtc_readl(struct omap_rtc *rtc, unsigned int reg)
+{
+ return readl(rtc->base + reg);
+}
+
+static inline void rtc_write(struct omap_rtc *rtc, unsigned int reg, u8 val)
+{
+ writeb(val, rtc->base + reg);
+}
+
+static inline void rtc_writel(struct omap_rtc *rtc, unsigned int reg, u32 val)
+{
+ writel(val, rtc->base + reg);
+}
+
+static void am3352_rtc_unlock(struct omap_rtc *rtc)
+{
+ rtc_writel(rtc, OMAP_RTC_KICK0_REG, KICK0_VALUE);
+ rtc_writel(rtc, OMAP_RTC_KICK1_REG, KICK1_VALUE);
+}
+
+static void am3352_rtc_lock(struct omap_rtc *rtc)
+{
+ rtc_writel(rtc, OMAP_RTC_KICK0_REG, 0);
+ rtc_writel(rtc, OMAP_RTC_KICK1_REG, 0);
+}
+
+static void default_rtc_unlock(struct omap_rtc *rtc)
+{
+}
+
+static void default_rtc_lock(struct omap_rtc *rtc)
+{
+}
+
+/*
+ * We rely on the rtc framework to handle locking (rtc->ops_lock),
+ * so the only other requirement is that register accesses which
+ * require BUSY to be clear are made with IRQs locally disabled
+ */
+static void rtc_wait_not_busy(struct omap_rtc *rtc)
+{
+ int count;
+ u8 status;
+
+ /* BUSY may stay active for 1/32768 second (~30 usec) */
+ for (count = 0; count < 50; count++) {
+ status = rtc_read(rtc, OMAP_RTC_STATUS_REG);
+ if (!(status & OMAP_RTC_STATUS_BUSY))
+ break;
+ udelay(1);
+ }
+ /* now we have ~15 usec to read/write various registers */
+}
+
+static irqreturn_t rtc_irq(int irq, void *dev_id)
+{
+ struct omap_rtc *rtc = dev_id;
+ unsigned long events = 0;
+ u8 irq_data;
+
+ irq_data = rtc_read(rtc, OMAP_RTC_STATUS_REG);
+
+ /* alarm irq? */
+ if (irq_data & OMAP_RTC_STATUS_ALARM) {
+ rtc->type->unlock(rtc);
+ rtc_write(rtc, OMAP_RTC_STATUS_REG, OMAP_RTC_STATUS_ALARM);
+ rtc->type->lock(rtc);
+ events |= RTC_IRQF | RTC_AF;
+ }
+
+ /* 1/sec periodic/update irq? */
+ if (irq_data & OMAP_RTC_STATUS_1S_EVENT)
+ events |= RTC_IRQF | RTC_UF;
+
+ rtc_update_irq(rtc->rtc, 1, events);
+
+ return IRQ_HANDLED;
+}
+
+static int omap_rtc_alarm_irq_enable(struct device *dev, unsigned int enabled)
+{
+ struct omap_rtc *rtc = dev_get_drvdata(dev);
+ u8 reg, irqwake_reg = 0;
+
+ local_irq_disable();
+ rtc_wait_not_busy(rtc);
+ reg = rtc_read(rtc, OMAP_RTC_INTERRUPTS_REG);
+ if (rtc->type->has_irqwakeen)
+ irqwake_reg = rtc_read(rtc, OMAP_RTC_IRQWAKEEN);
+
+ if (enabled) {
+ reg |= OMAP_RTC_INTERRUPTS_IT_ALARM;
+ irqwake_reg |= OMAP_RTC_IRQWAKEEN_ALARM_WAKEEN;
+ } else {
+ reg &= ~OMAP_RTC_INTERRUPTS_IT_ALARM;
+ irqwake_reg &= ~OMAP_RTC_IRQWAKEEN_ALARM_WAKEEN;
+ }
+ rtc_wait_not_busy(rtc);
+ rtc->type->unlock(rtc);
+ rtc_write(rtc, OMAP_RTC_INTERRUPTS_REG, reg);
+ if (rtc->type->has_irqwakeen)
+ rtc_write(rtc, OMAP_RTC_IRQWAKEEN, irqwake_reg);
+ rtc->type->lock(rtc);
+ local_irq_enable();
+
+ return 0;
+}
+
+/* this hardware doesn't support "don't care" alarm fields */
+static int tm2bcd(struct rtc_time *tm)
+{
+ if (rtc_valid_tm(tm) != 0)
+ return -EINVAL;
+
+ tm->tm_sec = bin2bcd(tm->tm_sec);
+ tm->tm_min = bin2bcd(tm->tm_min);
+ tm->tm_hour = bin2bcd(tm->tm_hour);
+ tm->tm_mday = bin2bcd(tm->tm_mday);
+
+ tm->tm_mon = bin2bcd(tm->tm_mon + 1);
+
+ /* epoch == 1900 */
+ if (tm->tm_year < 100 || tm->tm_year > 199)
+ return -EINVAL;
+ tm->tm_year = bin2bcd(tm->tm_year - 100);
+
+ return 0;
+}
+
+static void bcd2tm(struct rtc_time *tm)
+{
+ tm->tm_sec = bcd2bin(tm->tm_sec);
+ tm->tm_min = bcd2bin(tm->tm_min);
+ tm->tm_hour = bcd2bin(tm->tm_hour);
+ tm->tm_mday = bcd2bin(tm->tm_mday);
+ tm->tm_mon = bcd2bin(tm->tm_mon) - 1;
+ /* epoch == 1900 */
+ tm->tm_year = bcd2bin(tm->tm_year) + 100;
+}
+
+static void omap_rtc_read_time_raw(struct omap_rtc *rtc, struct rtc_time *tm)
+{
+ tm->tm_sec = rtc_read(rtc, OMAP_RTC_SECONDS_REG);
+ tm->tm_min = rtc_read(rtc, OMAP_RTC_MINUTES_REG);
+ tm->tm_hour = rtc_read(rtc, OMAP_RTC_HOURS_REG);
+ tm->tm_mday = rtc_read(rtc, OMAP_RTC_DAYS_REG);
+ tm->tm_mon = rtc_read(rtc, OMAP_RTC_MONTHS_REG);
+ tm->tm_year = rtc_read(rtc, OMAP_RTC_YEARS_REG);
+}
+
+static int omap_rtc_read_time(struct device *dev, struct rtc_time *tm)
+{
+ struct omap_rtc *rtc = dev_get_drvdata(dev);
+
+ /* we don't report wday/yday/isdst ... */
+ local_irq_disable();
+ rtc_wait_not_busy(rtc);
+ omap_rtc_read_time_raw(rtc, tm);
+ local_irq_enable();
+
+ bcd2tm(tm);
+
+ return 0;
+}
+
+static int omap_rtc_set_time(struct device *dev, struct rtc_time *tm)
+{
+ struct omap_rtc *rtc = dev_get_drvdata(dev);
+
+ if (tm2bcd(tm) < 0)
+ return -EINVAL;
+
+ local_irq_disable();
+ rtc_wait_not_busy(rtc);
+
+ rtc->type->unlock(rtc);
+ rtc_write(rtc, OMAP_RTC_YEARS_REG, tm->tm_year);
+ rtc_write(rtc, OMAP_RTC_MONTHS_REG, tm->tm_mon);
+ rtc_write(rtc, OMAP_RTC_DAYS_REG, tm->tm_mday);
+ rtc_write(rtc, OMAP_RTC_HOURS_REG, tm->tm_hour);
+ rtc_write(rtc, OMAP_RTC_MINUTES_REG, tm->tm_min);
+ rtc_write(rtc, OMAP_RTC_SECONDS_REG, tm->tm_sec);
+ rtc->type->lock(rtc);
+
+ local_irq_enable();
+
+ return 0;
+}
+
+static int omap_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *alm)
+{
+ struct omap_rtc *rtc = dev_get_drvdata(dev);
+ u8 interrupts;
+
+ local_irq_disable();
+ rtc_wait_not_busy(rtc);
+
+ alm->time.tm_sec = rtc_read(rtc, OMAP_RTC_ALARM_SECONDS_REG);
+ alm->time.tm_min = rtc_read(rtc, OMAP_RTC_ALARM_MINUTES_REG);
+ alm->time.tm_hour = rtc_read(rtc, OMAP_RTC_ALARM_HOURS_REG);
+ alm->time.tm_mday = rtc_read(rtc, OMAP_RTC_ALARM_DAYS_REG);
+ alm->time.tm_mon = rtc_read(rtc, OMAP_RTC_ALARM_MONTHS_REG);
+ alm->time.tm_year = rtc_read(rtc, OMAP_RTC_ALARM_YEARS_REG);
+
+ local_irq_enable();
+
+ bcd2tm(&alm->time);
+
+ interrupts = rtc_read(rtc, OMAP_RTC_INTERRUPTS_REG);
+ alm->enabled = !!(interrupts & OMAP_RTC_INTERRUPTS_IT_ALARM);
+
+ return 0;
+}
+
+static int omap_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alm)
+{
+ struct omap_rtc *rtc = dev_get_drvdata(dev);
+ u8 reg, irqwake_reg = 0;
+
+ if (tm2bcd(&alm->time) < 0)
+ return -EINVAL;
+
+ local_irq_disable();
+ rtc_wait_not_busy(rtc);
+
+ rtc->type->unlock(rtc);
+ rtc_write(rtc, OMAP_RTC_ALARM_YEARS_REG, alm->time.tm_year);
+ rtc_write(rtc, OMAP_RTC_ALARM_MONTHS_REG, alm->time.tm_mon);
+ rtc_write(rtc, OMAP_RTC_ALARM_DAYS_REG, alm->time.tm_mday);
+ rtc_write(rtc, OMAP_RTC_ALARM_HOURS_REG, alm->time.tm_hour);
+ rtc_write(rtc, OMAP_RTC_ALARM_MINUTES_REG, alm->time.tm_min);
+ rtc_write(rtc, OMAP_RTC_ALARM_SECONDS_REG, alm->time.tm_sec);
+
+ reg = rtc_read(rtc, OMAP_RTC_INTERRUPTS_REG);
+ if (rtc->type->has_irqwakeen)
+ irqwake_reg = rtc_read(rtc, OMAP_RTC_IRQWAKEEN);
+
+ if (alm->enabled) {
+ reg |= OMAP_RTC_INTERRUPTS_IT_ALARM;
+ irqwake_reg |= OMAP_RTC_IRQWAKEEN_ALARM_WAKEEN;
+ } else {
+ reg &= ~OMAP_RTC_INTERRUPTS_IT_ALARM;
+ irqwake_reg &= ~OMAP_RTC_IRQWAKEEN_ALARM_WAKEEN;
+ }
+ rtc_write(rtc, OMAP_RTC_INTERRUPTS_REG, reg);
+ if (rtc->type->has_irqwakeen)
+ rtc_write(rtc, OMAP_RTC_IRQWAKEEN, irqwake_reg);
+ rtc->type->lock(rtc);
+
+ local_irq_enable();
+
+ return 0;
+}
+
+static struct omap_rtc *omap_rtc_power_off_rtc;
+
+/*
+ * omap_rtc_poweroff: RTC-controlled power off
+ *
+ * The RTC can be used to control an external PMIC via the pmic_power_en pin,
+ * which can be configured to transition to OFF on ALARM2 events.
+ *
+ * Notes:
+ * The two-second alarm offset is the shortest offset possible as the alarm
+ * registers must be set before the next timer update and the offset
+ * calculation is too heavy for everything to be done within a single access
+ * period (~15 us).
+ *
+ * Called with local interrupts disabled.
+ */
+static void omap_rtc_power_off(void)
+{
+ struct omap_rtc *rtc = omap_rtc_power_off_rtc;
+ struct rtc_time tm;
+ unsigned long now;
+ u32 val;
+
+ rtc->type->unlock(rtc);
+ /* enable pmic_power_en control */
+ val = rtc_readl(rtc, OMAP_RTC_PMIC_REG);
+ rtc_writel(rtc, OMAP_RTC_PMIC_REG, val | OMAP_RTC_PMIC_POWER_EN_EN);
+
+ /* set alarm two seconds from now */
+ omap_rtc_read_time_raw(rtc, &tm);
+ bcd2tm(&tm);
+ rtc_tm_to_time(&tm, &now);
+ rtc_time_to_tm(now + 2, &tm);
+
+ if (tm2bcd(&tm) < 0) {
+ dev_err(&rtc->rtc->dev, "power off failed\n");
+ return;
+ }
+
+ rtc_wait_not_busy(rtc);
+
+ rtc_write(rtc, OMAP_RTC_ALARM2_SECONDS_REG, tm.tm_sec);
+ rtc_write(rtc, OMAP_RTC_ALARM2_MINUTES_REG, tm.tm_min);
+ rtc_write(rtc, OMAP_RTC_ALARM2_HOURS_REG, tm.tm_hour);
+ rtc_write(rtc, OMAP_RTC_ALARM2_DAYS_REG, tm.tm_mday);
+ rtc_write(rtc, OMAP_RTC_ALARM2_MONTHS_REG, tm.tm_mon);
+ rtc_write(rtc, OMAP_RTC_ALARM2_YEARS_REG, tm.tm_year);
+
+ /*
+ * enable ALARM2 interrupt
+ *
+ * NOTE: this fails on AM3352 if rtc_write (writeb) is used
+ */
+ val = rtc_read(rtc, OMAP_RTC_INTERRUPTS_REG);
+ rtc_writel(rtc, OMAP_RTC_INTERRUPTS_REG,
+ val | OMAP_RTC_INTERRUPTS_IT_ALARM2);
+ rtc->type->lock(rtc);
+
+ /*
+ * Wait for alarm to trigger (within two seconds) and external PMIC to
+ * power off the system. Add a 500 ms margin for external latencies
+ * (e.g. debounce circuits).
+ */
+ mdelay(2500);
+}
+
+static struct rtc_class_ops omap_rtc_ops = {
+ .read_time = omap_rtc_read_time,
+ .set_time = omap_rtc_set_time,
+ .read_alarm = omap_rtc_read_alarm,
+ .set_alarm = omap_rtc_set_alarm,
+ .alarm_irq_enable = omap_rtc_alarm_irq_enable,
+};
+
+static const struct omap_rtc_device_type omap_rtc_default_type = {
+ .has_power_up_reset = true,
+ .lock = default_rtc_lock,
+ .unlock = default_rtc_unlock,
+};
+
+static const struct omap_rtc_device_type omap_rtc_am3352_type = {
+ .has_32kclk_en = true,
+ .has_irqwakeen = true,
+ .has_pmic_mode = true,
+ .lock = am3352_rtc_lock,
+ .unlock = am3352_rtc_unlock,
+};
+
+static const struct omap_rtc_device_type omap_rtc_da830_type = {
+ .lock = am3352_rtc_lock,
+ .unlock = am3352_rtc_unlock,
+};
+
+static const struct platform_device_id omap_rtc_id_table[] = {
+ {
+ .name = "omap_rtc",
+ .driver_data = (kernel_ulong_t)&omap_rtc_default_type,
+ }, {
+ .name = "am3352-rtc",
+ .driver_data = (kernel_ulong_t)&omap_rtc_am3352_type,
+ }, {
+ .name = "da830-rtc",
+ .driver_data = (kernel_ulong_t)&omap_rtc_da830_type,
+ }, {
+ /* sentinel */
+ }
+};
+MODULE_DEVICE_TABLE(platform, omap_rtc_id_table);
+
+static const struct of_device_id omap_rtc_of_match[] = {
+ {
+ .compatible = "ti,am3352-rtc",
+ .data = &omap_rtc_am3352_type,
+ }, {
+ .compatible = "ti,da830-rtc",
+ .data = &omap_rtc_da830_type,
+ }, {
+ /* sentinel */
+ }
+};
+MODULE_DEVICE_TABLE(of, omap_rtc_of_match);
+
+static int omap_rtc_probe(struct platform_device *pdev)
+{
+ struct omap_rtc *rtc;
+ struct resource *res;
+ u8 reg, mask, new_ctrl;
+ const struct platform_device_id *id_entry;
+ const struct of_device_id *of_id;
+ int ret;
+
+ rtc = devm_kzalloc(&pdev->dev, sizeof(*rtc), GFP_KERNEL);
+ if (!rtc)
+ return -ENOMEM;
+
+ of_id = of_match_device(omap_rtc_of_match, &pdev->dev);
+ if (of_id) {
+ rtc->type = of_id->data;
+ rtc->is_pmic_controller = rtc->type->has_pmic_mode &&
+ of_property_read_bool(pdev->dev.of_node,
+ "system-power-controller");
+ } else {
+ id_entry = platform_get_device_id(pdev);
+ rtc->type = (void *)id_entry->driver_data;
+ }
+
+ rtc->irq_timer = platform_get_irq(pdev, 0);
+ if (rtc->irq_timer <= 0)
+ return -ENOENT;
+
+ rtc->irq_alarm = platform_get_irq(pdev, 1);
+ if (rtc->irq_alarm <= 0)
+ return -ENOENT;
+
+ res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+ rtc->base = devm_ioremap_resource(&pdev->dev, res);
+ if (IS_ERR(rtc->base))
+ return PTR_ERR(rtc->base);
+
+ platform_set_drvdata(pdev, rtc);
+
+ /* Enable the clock/module so that we can access the registers */
+ pm_runtime_enable(&pdev->dev);
+ pm_runtime_get_sync(&pdev->dev);
+
+ rtc->type->unlock(rtc);
+
+ /*
+ * disable interrupts
+ *
+ * NOTE: ALARM2 is not cleared on AM3352 if rtc_write (writeb) is used
+ */
+ rtc_writel(rtc, OMAP_RTC_INTERRUPTS_REG, 0);
+
+ /* enable RTC functional clock */
+ if (rtc->type->has_32kclk_en) {
+ reg = rtc_read(rtc, OMAP_RTC_OSC_REG);
+ rtc_writel(rtc, OMAP_RTC_OSC_REG,
+ reg | OMAP_RTC_OSC_32KCLK_EN);
+ }
+
+ /* clear old status */
+ reg = rtc_read(rtc, OMAP_RTC_STATUS_REG);
+
+ mask = OMAP_RTC_STATUS_ALARM;
+
+ if (rtc->type->has_pmic_mode)
+ mask |= OMAP_RTC_STATUS_ALARM2;
+
+ if (rtc->type->has_power_up_reset) {
+ mask |= OMAP_RTC_STATUS_POWER_UP;
+ if (reg & OMAP_RTC_STATUS_POWER_UP)
+ dev_info(&pdev->dev, "RTC power up reset detected\n");
+ }
+
+ if (reg & mask)
+ rtc_write(rtc, OMAP_RTC_STATUS_REG, reg & mask);
+
+ /* On boards with split power, RTC_ON_NOFF won't reset the RTC */
+ reg = rtc_read(rtc, OMAP_RTC_CTRL_REG);
+ if (reg & OMAP_RTC_CTRL_STOP)
+ dev_info(&pdev->dev, "already running\n");
+
+ /* force to 24 hour mode */
+ new_ctrl = reg & (OMAP_RTC_CTRL_SPLIT | OMAP_RTC_CTRL_AUTO_COMP);
+ new_ctrl |= OMAP_RTC_CTRL_STOP;
+
+ /*
+ * BOARD-SPECIFIC CUSTOMIZATION CAN GO HERE:
+ *
+ * - Device wake-up capability setting should come through chip
+ * init logic. OMAP1 boards should initialize the "wakeup capable"
+ * flag in the platform device if the board is wired right for
+ * being woken up by RTC alarm. For OMAP-L138, this capability
+ * is built into the SoC by the "Deep Sleep" capability.
+ *
+ * - Boards wired so RTC_ON_nOFF is used as the reset signal,
+ * rather than nPWRON_RESET, should forcibly enable split
+ * power mode. (Some chip errata report that RTC_CTRL_SPLIT
+ * is write-only, and always reads as zero...)
+ */
+
+ if (new_ctrl & OMAP_RTC_CTRL_SPLIT)
+ dev_info(&pdev->dev, "split power mode\n");
+
+ if (reg != new_ctrl)
+ rtc_write(rtc, OMAP_RTC_CTRL_REG, new_ctrl);
+
+ rtc->type->lock(rtc);
+
+ device_init_wakeup(&pdev->dev, true);
+
+ rtc->rtc = devm_rtc_device_register(&pdev->dev, pdev->name,
+ &omap_rtc_ops, THIS_MODULE);
+ if (IS_ERR(rtc->rtc)) {
+ ret = PTR_ERR(rtc->rtc);
+ goto err;
+ }
+
+ /* handle periodic and alarm irqs */
+ ret = devm_request_irq(&pdev->dev, rtc->irq_timer, rtc_irq, 0,
+ dev_name(&rtc->rtc->dev), rtc);
+ if (ret)
+ goto err;
+
+ if (rtc->irq_timer != rtc->irq_alarm) {
+ ret = devm_request_irq(&pdev->dev, rtc->irq_alarm, rtc_irq, 0,
+ dev_name(&rtc->rtc->dev), rtc);
+ if (ret)
+ goto err;
+ }
+
+ if (rtc->is_pmic_controller) {
+ if (!pm_power_off) {
+ omap_rtc_power_off_rtc = rtc;
+ pm_power_off = omap_rtc_power_off;
+ }
+ }
+
+ return 0;
+
+err:
+ device_init_wakeup(&pdev->dev, false);
+ rtc->type->lock(rtc);
+ pm_runtime_put_sync(&pdev->dev);
+ pm_runtime_disable(&pdev->dev);
+
+ return ret;
+}
+
+static int __exit omap_rtc_remove(struct platform_device *pdev)
+{
+ struct omap_rtc *rtc = platform_get_drvdata(pdev);
+
+ if (pm_power_off == omap_rtc_power_off &&
+ omap_rtc_power_off_rtc == rtc) {
+ pm_power_off = NULL;
+ omap_rtc_power_off_rtc = NULL;
+ }
+
+ device_init_wakeup(&pdev->dev, 0);
+
+ rtc->type->unlock(rtc);
+ /* leave rtc running, but disable irqs */
+ rtc_write(rtc, OMAP_RTC_INTERRUPTS_REG, 0);
+
+ rtc->type->lock(rtc);
+
+ /* Disable the clock/module */
+ pm_runtime_put_sync(&pdev->dev);
+ pm_runtime_disable(&pdev->dev);
+
+ return 0;
+}
+
+#ifdef CONFIG_PM_SLEEP
+static int omap_rtc_suspend(struct device *dev)
+{
+ struct omap_rtc *rtc = dev_get_drvdata(dev);
+
+ rtc->interrupts_reg = rtc_read(rtc, OMAP_RTC_INTERRUPTS_REG);
+
+ rtc->type->unlock(rtc);
+ /*
+ * FIXME: the RTC alarm is not currently acting as a wakeup event
+ * source on some platforms, and in fact this enable() call is just
+ * saving a flag that's never used...
+ */
+ if (device_may_wakeup(dev))
+ enable_irq_wake(rtc->irq_alarm);
+ else
+ rtc_write(rtc, OMAP_RTC_INTERRUPTS_REG, 0);
+ rtc->type->lock(rtc);
+
+ /* Disable the clock/module */
+ pm_runtime_put_sync(dev);
+
+ return 0;
+}
+
+static int omap_rtc_resume(struct device *dev)
+{
+ struct omap_rtc *rtc = dev_get_drvdata(dev);
+
+ /* Enable the clock/module so that we can access the registers */
+ pm_runtime_get_sync(dev);
+
+ rtc->type->unlock(rtc);
+ if (device_may_wakeup(dev))
+ disable_irq_wake(rtc->irq_alarm);
+ else
+ rtc_write(rtc, OMAP_RTC_INTERRUPTS_REG, rtc->interrupts_reg);
+ rtc->type->lock(rtc);
+
+ return 0;
+}
+#endif
+
+static SIMPLE_DEV_PM_OPS(omap_rtc_pm_ops, omap_rtc_suspend, omap_rtc_resume);
+
+static void omap_rtc_shutdown(struct platform_device *pdev)
+{
+ struct omap_rtc *rtc = platform_get_drvdata(pdev);
+ u8 mask;
+
+ /*
+ * Keep the ALARM interrupt enabled to allow the system to power up on
+ * alarm events.
+ */
+ rtc->type->unlock(rtc);
+ mask = rtc_read(rtc, OMAP_RTC_INTERRUPTS_REG);
+ mask &= OMAP_RTC_INTERRUPTS_IT_ALARM;
+ rtc_write(rtc, OMAP_RTC_INTERRUPTS_REG, mask);
+ rtc->type->lock(rtc);
+}
+
+static struct platform_driver omap_rtc_driver = {
+ .probe = omap_rtc_probe,
+ .remove = __exit_p(omap_rtc_remove),
+ .shutdown = omap_rtc_shutdown,
+ .driver = {
+ .name = "omap_rtc",
+ .pm = &omap_rtc_pm_ops,
+ .of_match_table = omap_rtc_of_match,
+ },
+ .id_table = omap_rtc_id_table,
+};
+
+module_platform_driver(omap_rtc_driver);
+
+MODULE_ALIAS("platform:omap_rtc");
+MODULE_AUTHOR("George G. Davis (and others)");
+MODULE_LICENSE("GPL");