diff options
Diffstat (limited to 'drivers/rtc/rtc-omap.c')
| -rw-r--r-- | drivers/rtc/rtc-omap.c | 774 |
1 files changed, 774 insertions, 0 deletions
diff --git a/drivers/rtc/rtc-omap.c b/drivers/rtc/rtc-omap.c new file mode 100644 index 000000000..8b6355ffa --- /dev/null +++ b/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"); |