From 4352b8aee98005853aa63f57d6377282de17a33f Mon Sep 17 00:00:00 2001 From: Linus Torvalds Date: Sun, 23 Aug 2026 13:28:57 -0700 Subject: Merge tag 'i3c/for-7.3' of git://git.kernel.org/pub/scm/linux/kernel/git/i3c/linux Pull I3C updates from Alexandre Belloni: "A new driver this cycle, for the AMD AXI I3C controller. There are also new features such as IBI wakeup support, SETAASA device discovery and ACPI support for the the DAA methods, meaning we can now communicate with the SPD devices on DDR5 modules. New driver: - AMD AXI I3C master controller Subsystem: - I3C Common Command Code (CCC) handling improvements, especially around GET CCCs - SETAASA device discovery support - ACPI support for all existing DAA methods like SETDASA, SETNEWDA as well as I2C devices on I3C bus - IBI-based wakeup support Drivers: - dw: SETAASA support - mipi-i3c-hci: advertise IBI wakeup capability, AMD_PT I3C controller support, PIO queue management support for HCI v1.2 - renesas: improve suspend to RAM support, add runtime PM support" * tag 'i3c/for-7.3' of git://git.kernel.org/pub/scm/linux/kernel/git/i3c/linux: (70 commits) i3c: dw: reduce do_daa time if there's no client i3c: mipi-i3c-hci: Add support for AMD_PT I3C controller i3c: mipi-i3c-hci: Add PIO queue management support for HCI v1.2 i3c: mipi-i3c-hci: Fix missing STAT_IBI_STATUS_THLD in PIO mode i3c: dw: rename "pclk" to "apb" to match dt-binding i3c: dw: make struct dw_i3c_cmd smaller i3c: dw: use COMMAND_PORT_TRANSFER_ARG instead of hardcoding i3c: renesas: Don't register devices when ENTDAA times out i3c: master: dw-i3c-master: fix OD timing for first broadcast i3c: mipi-i3c-hci: Advertise IBI wakeup capability i3c: mipi-i3c-hci: Factor out i3c_hci_sysdev() i3c: mipi-i3c-hci-pci: Propagate I3C wakeup requirements to PCI i3c: master: Reject IBI requests from non-IBI-capable devices i3c: master: Add helper to query bus wakeup requirements i3c: master: Report wakeup events for IBIs i3c: master: Support IBI-based wakeup capability i3c: master: Fix potential UAF in i3c_device_match() i3c: master: Fix potential UAF in i3c_device_uevent() i3c: Make dev->desc locking assumptions explicit i3c: master: Fix use-after-free of master->this ... --- drivers/rtc/rtc-spear.c | 492 ++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 492 insertions(+) create mode 100644 drivers/rtc/rtc-spear.c (limited to 'drivers/rtc/rtc-spear.c') diff --git a/drivers/rtc/rtc-spear.c b/drivers/rtc/rtc-spear.c new file mode 100644 index 000000000..959acff8f --- /dev/null +++ b/drivers/rtc/rtc-spear.c @@ -0,0 +1,492 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * drivers/rtc/rtc-spear.c + * + * Copyright (C) 2010 ST Microelectronics + * Rajeev Kumar + */ + +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include + +/* RTC registers */ +#define TIME_REG 0x00 +#define DATE_REG 0x04 +#define ALARM_TIME_REG 0x08 +#define ALARM_DATE_REG 0x0C +#define CTRL_REG 0x10 +#define STATUS_REG 0x14 + +/* TIME_REG & ALARM_TIME_REG */ +#define SECONDS_UNITS (0xf<<0) /* seconds units position */ +#define SECONDS_TENS (0x7<<4) /* seconds tens position */ +#define MINUTES_UNITS (0xf<<8) /* minutes units position */ +#define MINUTES_TENS (0x7<<12) /* minutes tens position */ +#define HOURS_UNITS (0xf<<16) /* hours units position */ +#define HOURS_TENS (0x3<<20) /* hours tens position */ + +/* DATE_REG & ALARM_DATE_REG */ +#define DAYS_UNITS (0xf<<0) /* days units position */ +#define DAYS_TENS (0x3<<4) /* days tens position */ +#define MONTHS_UNITS (0xf<<8) /* months units position */ +#define MONTHS_TENS (0x1<<12) /* months tens position */ +#define YEARS_UNITS (0xf<<16) /* years units position */ +#define YEARS_TENS (0xf<<20) /* years tens position */ +#define YEARS_HUNDREDS (0xf<<24) /* years hundereds position */ +#define YEARS_MILLENIUMS (0xf<<28) /* years millenium position */ + +/* MASK SHIFT TIME_REG & ALARM_TIME_REG*/ +#define SECOND_SHIFT 0x00 /* seconds units */ +#define MINUTE_SHIFT 0x08 /* minutes units position */ +#define HOUR_SHIFT 0x10 /* hours units position */ +#define MDAY_SHIFT 0x00 /* Month day shift */ +#define MONTH_SHIFT 0x08 /* Month shift */ +#define YEAR_SHIFT 0x10 /* Year shift */ + +#define SECOND_MASK 0x7F +#define MIN_MASK 0x7F +#define HOUR_MASK 0x3F +#define DAY_MASK 0x3F +#define MONTH_MASK 0x7F +#define YEAR_MASK 0xFFFF + +/* date reg equal to time reg, for debug only */ +#define TIME_BYP (1<<9) +#define INT_ENABLE (1<<31) /* interrupt enable */ + +/* STATUS_REG */ +#define CLK_UNCONNECTED (1<<0) +#define PEND_WR_TIME (1<<2) +#define PEND_WR_DATE (1<<3) +#define LOST_WR_TIME (1<<4) +#define LOST_WR_DATE (1<<5) +#define RTC_INT_MASK (1<<31) +#define STATUS_BUSY (PEND_WR_TIME | PEND_WR_DATE) +#define STATUS_FAIL (LOST_WR_TIME | LOST_WR_DATE) + +struct spear_rtc_config { + struct rtc_device *rtc; + struct clk *clk; + spinlock_t lock; + void __iomem *ioaddr; + unsigned int irq_wake; +}; + +static inline void spear_rtc_clear_interrupt(struct spear_rtc_config *config) +{ + unsigned int val; + unsigned long flags; + + spin_lock_irqsave(&config->lock, flags); + val = readl(config->ioaddr + STATUS_REG); + val |= RTC_INT_MASK; + writel(val, config->ioaddr + STATUS_REG); + spin_unlock_irqrestore(&config->lock, flags); +} + +static inline void spear_rtc_enable_interrupt(struct spear_rtc_config *config) +{ + unsigned int val; + + val = readl(config->ioaddr + CTRL_REG); + if (!(val & INT_ENABLE)) { + spear_rtc_clear_interrupt(config); + val |= INT_ENABLE; + writel(val, config->ioaddr + CTRL_REG); + } +} + +static inline void spear_rtc_disable_interrupt(struct spear_rtc_config *config) +{ + unsigned int val; + + val = readl(config->ioaddr + CTRL_REG); + if (val & INT_ENABLE) { + val &= ~INT_ENABLE; + writel(val, config->ioaddr + CTRL_REG); + } +} + +static inline int is_write_complete(struct spear_rtc_config *config) +{ + int ret = 0; + unsigned long flags; + + spin_lock_irqsave(&config->lock, flags); + if ((readl(config->ioaddr + STATUS_REG)) & STATUS_FAIL) + ret = -EIO; + spin_unlock_irqrestore(&config->lock, flags); + + return ret; +} + +static void rtc_wait_not_busy(struct spear_rtc_config *config) +{ + int status, count = 0; + unsigned long flags; + + /* Assuming BUSY may stay active for 80 msec) */ + for (count = 0; count < 80; count++) { + spin_lock_irqsave(&config->lock, flags); + status = readl(config->ioaddr + STATUS_REG); + spin_unlock_irqrestore(&config->lock, flags); + if ((status & STATUS_BUSY) == 0) + break; + /* check status busy, after each msec */ + msleep(1); + } +} + +static irqreturn_t spear_rtc_irq(int irq, void *dev_id) +{ + struct spear_rtc_config *config = dev_id; + unsigned long events = 0; + unsigned int irq_data; + + spin_lock(&config->lock); + irq_data = readl(config->ioaddr + STATUS_REG); + spin_unlock(&config->lock); + + if ((irq_data & RTC_INT_MASK)) { + spear_rtc_clear_interrupt(config); + events = RTC_IRQF | RTC_AF; + rtc_update_irq(config->rtc, 1, events); + return IRQ_HANDLED; + } else + return IRQ_NONE; + +} + +static void tm2bcd(struct rtc_time *tm) +{ + 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); + tm->tm_year = bin2bcd(tm->tm_year); +} + +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); +} + +/* + * spear_rtc_read_time - set the time + * @dev: rtc device in use + * @tm: holds date and time + * + * This function read time and date. On success it will return 0 + * otherwise -ve error is returned. + */ +static int spear_rtc_read_time(struct device *dev, struct rtc_time *tm) +{ + struct spear_rtc_config *config = dev_get_drvdata(dev); + unsigned int time, date; + + /* we don't report wday/yday/isdst ... */ + rtc_wait_not_busy(config); + + do { + time = readl(config->ioaddr + TIME_REG); + date = readl(config->ioaddr + DATE_REG); + } while (time == readl(config->ioaddr + TIME_REG)); + tm->tm_sec = (time >> SECOND_SHIFT) & SECOND_MASK; + tm->tm_min = (time >> MINUTE_SHIFT) & MIN_MASK; + tm->tm_hour = (time >> HOUR_SHIFT) & HOUR_MASK; + tm->tm_mday = (date >> MDAY_SHIFT) & DAY_MASK; + tm->tm_mon = (date >> MONTH_SHIFT) & MONTH_MASK; + tm->tm_year = (date >> YEAR_SHIFT) & YEAR_MASK; + + bcd2tm(tm); + return 0; +} + +/* + * spear_rtc_set_time - set the time + * @dev: rtc device in use + * @tm: holds date and time + * + * This function set time and date. On success it will return 0 + * otherwise -ve error is returned. + */ +static int spear_rtc_set_time(struct device *dev, struct rtc_time *tm) +{ + struct spear_rtc_config *config = dev_get_drvdata(dev); + unsigned int time, date; + + tm2bcd(tm); + + rtc_wait_not_busy(config); + time = (tm->tm_sec << SECOND_SHIFT) | (tm->tm_min << MINUTE_SHIFT) | + (tm->tm_hour << HOUR_SHIFT); + date = (tm->tm_mday << MDAY_SHIFT) | (tm->tm_mon << MONTH_SHIFT) | + (tm->tm_year << YEAR_SHIFT); + writel(time, config->ioaddr + TIME_REG); + writel(date, config->ioaddr + DATE_REG); + + return is_write_complete(config); +} + +/* + * spear_rtc_read_alarm - read the alarm time + * @dev: rtc device in use + * @alm: holds alarm date and time + * + * This function read alarm time and date. On success it will return 0 + * otherwise -ve error is returned. + */ +static int spear_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *alm) +{ + struct spear_rtc_config *config = dev_get_drvdata(dev); + unsigned int time, date; + + rtc_wait_not_busy(config); + + time = readl(config->ioaddr + ALARM_TIME_REG); + date = readl(config->ioaddr + ALARM_DATE_REG); + alm->time.tm_sec = (time >> SECOND_SHIFT) & SECOND_MASK; + alm->time.tm_min = (time >> MINUTE_SHIFT) & MIN_MASK; + alm->time.tm_hour = (time >> HOUR_SHIFT) & HOUR_MASK; + alm->time.tm_mday = (date >> MDAY_SHIFT) & DAY_MASK; + alm->time.tm_mon = (date >> MONTH_SHIFT) & MONTH_MASK; + alm->time.tm_year = (date >> YEAR_SHIFT) & YEAR_MASK; + + bcd2tm(&alm->time); + alm->enabled = readl(config->ioaddr + CTRL_REG) & INT_ENABLE; + + return 0; +} + +/* + * spear_rtc_set_alarm - set the alarm time + * @dev: rtc device in use + * @alm: holds alarm date and time + * + * This function set alarm time and date. On success it will return 0 + * otherwise -ve error is returned. + */ +static int spear_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alm) +{ + struct spear_rtc_config *config = dev_get_drvdata(dev); + unsigned int time, date; + int err; + + tm2bcd(&alm->time); + + rtc_wait_not_busy(config); + + time = (alm->time.tm_sec << SECOND_SHIFT) | (alm->time.tm_min << + MINUTE_SHIFT) | (alm->time.tm_hour << HOUR_SHIFT); + date = (alm->time.tm_mday << MDAY_SHIFT) | (alm->time.tm_mon << + MONTH_SHIFT) | (alm->time.tm_year << YEAR_SHIFT); + + writel(time, config->ioaddr + ALARM_TIME_REG); + writel(date, config->ioaddr + ALARM_DATE_REG); + err = is_write_complete(config); + if (err < 0) + return err; + + if (alm->enabled) + spear_rtc_enable_interrupt(config); + else + spear_rtc_disable_interrupt(config); + + return 0; +} + +static int spear_alarm_irq_enable(struct device *dev, unsigned int enabled) +{ + struct spear_rtc_config *config = dev_get_drvdata(dev); + int ret = 0; + + spear_rtc_clear_interrupt(config); + + switch (enabled) { + case 0: + /* alarm off */ + spear_rtc_disable_interrupt(config); + break; + case 1: + /* alarm on */ + spear_rtc_enable_interrupt(config); + break; + default: + ret = -EINVAL; + break; + } + + return ret; +} + +static const struct rtc_class_ops spear_rtc_ops = { + .read_time = spear_rtc_read_time, + .set_time = spear_rtc_set_time, + .read_alarm = spear_rtc_read_alarm, + .set_alarm = spear_rtc_set_alarm, + .alarm_irq_enable = spear_alarm_irq_enable, +}; + +static int spear_rtc_probe(struct platform_device *pdev) +{ + struct spear_rtc_config *config; + int status = 0; + int irq; + + config = devm_kzalloc(&pdev->dev, sizeof(*config), GFP_KERNEL); + if (!config) + return -ENOMEM; + + config->rtc = devm_rtc_allocate_device(&pdev->dev); + if (IS_ERR(config->rtc)) + return PTR_ERR(config->rtc); + + /* alarm irqs */ + irq = platform_get_irq(pdev, 0); + if (irq < 0) + return irq; + + status = devm_request_irq(&pdev->dev, irq, spear_rtc_irq, 0, pdev->name, + config); + if (status) { + dev_err(&pdev->dev, "Alarm interrupt IRQ%d already claimed\n", + irq); + return status; + } + + config->ioaddr = devm_platform_ioremap_resource(pdev, 0); + if (IS_ERR(config->ioaddr)) + return PTR_ERR(config->ioaddr); + + config->clk = devm_clk_get(&pdev->dev, NULL); + if (IS_ERR(config->clk)) + return PTR_ERR(config->clk); + + status = clk_prepare_enable(config->clk); + if (status < 0) + return status; + + spin_lock_init(&config->lock); + platform_set_drvdata(pdev, config); + + config->rtc->ops = &spear_rtc_ops; + config->rtc->range_min = RTC_TIMESTAMP_BEGIN_0000; + config->rtc->range_max = RTC_TIMESTAMP_END_9999; + + status = devm_rtc_register_device(config->rtc); + if (status) + goto err_disable_clock; + + if (!device_can_wakeup(&pdev->dev)) + device_init_wakeup(&pdev->dev, true); + + return 0; + +err_disable_clock: + clk_disable_unprepare(config->clk); + + return status; +} + +static void spear_rtc_remove(struct platform_device *pdev) +{ + struct spear_rtc_config *config = platform_get_drvdata(pdev); + + spear_rtc_disable_interrupt(config); + clk_disable_unprepare(config->clk); + device_init_wakeup(&pdev->dev, false); +} + +#ifdef CONFIG_PM_SLEEP +static int spear_rtc_suspend(struct device *dev) +{ + struct platform_device *pdev = to_platform_device(dev); + struct spear_rtc_config *config = platform_get_drvdata(pdev); + int irq; + + irq = platform_get_irq(pdev, 0); + if (device_may_wakeup(&pdev->dev)) { + if (!enable_irq_wake(irq)) + config->irq_wake = 1; + } else { + spear_rtc_disable_interrupt(config); + clk_disable(config->clk); + } + + return 0; +} + +static int spear_rtc_resume(struct device *dev) +{ + struct platform_device *pdev = to_platform_device(dev); + struct spear_rtc_config *config = platform_get_drvdata(pdev); + int irq; + + irq = platform_get_irq(pdev, 0); + + if (device_may_wakeup(&pdev->dev)) { + if (config->irq_wake) { + disable_irq_wake(irq); + config->irq_wake = 0; + } + } else { + clk_enable(config->clk); + spear_rtc_enable_interrupt(config); + } + + return 0; +} +#endif + +static SIMPLE_DEV_PM_OPS(spear_rtc_pm_ops, spear_rtc_suspend, spear_rtc_resume); + +static void spear_rtc_shutdown(struct platform_device *pdev) +{ + struct spear_rtc_config *config = platform_get_drvdata(pdev); + + spear_rtc_disable_interrupt(config); + clk_disable(config->clk); +} + +#ifdef CONFIG_OF +static const struct of_device_id spear_rtc_id_table[] = { + { .compatible = "st,spear600-rtc" }, + {} +}; +MODULE_DEVICE_TABLE(of, spear_rtc_id_table); +#endif + +static struct platform_driver spear_rtc_driver = { + .probe = spear_rtc_probe, + .remove = spear_rtc_remove, + .shutdown = spear_rtc_shutdown, + .driver = { + .name = "rtc-spear", + .pm = &spear_rtc_pm_ops, + .of_match_table = of_match_ptr(spear_rtc_id_table), + }, +}; + +module_platform_driver(spear_rtc_driver); + +MODULE_ALIAS("platform:rtc-spear"); +MODULE_AUTHOR("Rajeev Kumar "); +MODULE_DESCRIPTION("ST SPEAr Realtime Clock Driver (RTC)"); +MODULE_LICENSE("GPL"); -- cgit v1.3.1