diff options
| author | Linus Torvalds <torvalds@linux-foundation.org> | 2026-08-23 13:28:57 -0700 |
|---|---|---|
| committer | Linus Torvalds <torvalds@linux-foundation.org> | 2026-08-23 13:28:57 -0700 |
| commit | 4352b8aee98005853aa63f57d6377282de17a33f (patch) | |
| tree | 27614d7a9ef05c32d089004e104364ce42324837 /drivers/rtc/rtc-lpc32xx.c | |
| download | linux-stable-4352b8aee98005853aa63f57d6377282de17a33f.tar.gz linux-stable-4352b8aee98005853aa63f57d6377282de17a33f.zip | |
Merge tag 'i3c/for-7.3' of git://git.kernel.org/pub/scm/linux/kernel/git/i3c/linuxgrafted
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
...
Diffstat (limited to 'drivers/rtc/rtc-lpc32xx.c')
| -rw-r--r-- | drivers/rtc/rtc-lpc32xx.c | 360 |
1 files changed, 360 insertions, 0 deletions
diff --git a/drivers/rtc/rtc-lpc32xx.c b/drivers/rtc/rtc-lpc32xx.c new file mode 100644 index 000000000..74280bffe --- /dev/null +++ b/drivers/rtc/rtc-lpc32xx.c @@ -0,0 +1,360 @@ +// SPDX-License-Identifier: GPL-2.0+ +/* + * Copyright (C) 2010 NXP Semiconductors + */ + +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/init.h> +#include <linux/platform_device.h> +#include <linux/spinlock.h> +#include <linux/rtc.h> +#include <linux/slab.h> +#include <linux/io.h> +#include <linux/of.h> + +/* + * Clock and Power control register offsets + */ +#define LPC32XX_RTC_UCOUNT 0x00 +#define LPC32XX_RTC_DCOUNT 0x04 +#define LPC32XX_RTC_MATCH0 0x08 +#define LPC32XX_RTC_MATCH1 0x0C +#define LPC32XX_RTC_CTRL 0x10 +#define LPC32XX_RTC_INTSTAT 0x14 +#define LPC32XX_RTC_KEY 0x18 +#define LPC32XX_RTC_SRAM 0x80 + +#define LPC32XX_RTC_CTRL_MATCH0 (1 << 0) +#define LPC32XX_RTC_CTRL_MATCH1 (1 << 1) +#define LPC32XX_RTC_CTRL_ONSW_MATCH0 (1 << 2) +#define LPC32XX_RTC_CTRL_ONSW_MATCH1 (1 << 3) +#define LPC32XX_RTC_CTRL_SW_RESET (1 << 4) +#define LPC32XX_RTC_CTRL_CNTR_DIS (1 << 6) +#define LPC32XX_RTC_CTRL_ONSW_FORCE_HI (1 << 7) + +#define LPC32XX_RTC_INTSTAT_MATCH0 (1 << 0) +#define LPC32XX_RTC_INTSTAT_MATCH1 (1 << 1) +#define LPC32XX_RTC_INTSTAT_ONSW (1 << 2) + +#define LPC32XX_RTC_KEY_ONSW_LOADVAL 0xB5C13F27 + +#define rtc_readl(dev, reg) \ + __raw_readl((dev)->rtc_base + (reg)) +#define rtc_writel(dev, reg, val) \ + __raw_writel((val), (dev)->rtc_base + (reg)) + +struct lpc32xx_rtc { + void __iomem *rtc_base; + int irq; + unsigned char alarm_enabled; + struct rtc_device *rtc; + spinlock_t lock; +}; + +static int lpc32xx_rtc_read_time(struct device *dev, struct rtc_time *time) +{ + unsigned long elapsed_sec; + struct lpc32xx_rtc *rtc = dev_get_drvdata(dev); + + elapsed_sec = rtc_readl(rtc, LPC32XX_RTC_UCOUNT); + rtc_time64_to_tm(elapsed_sec, time); + + return 0; +} + +static int lpc32xx_rtc_set_time(struct device *dev, struct rtc_time *time) +{ + struct lpc32xx_rtc *rtc = dev_get_drvdata(dev); + u32 secs = rtc_tm_to_time64(time); + u32 tmp; + + spin_lock_irq(&rtc->lock); + + /* RTC must be disabled during count update */ + tmp = rtc_readl(rtc, LPC32XX_RTC_CTRL); + rtc_writel(rtc, LPC32XX_RTC_CTRL, tmp | LPC32XX_RTC_CTRL_CNTR_DIS); + rtc_writel(rtc, LPC32XX_RTC_UCOUNT, secs); + rtc_writel(rtc, LPC32XX_RTC_DCOUNT, 0xFFFFFFFF - secs); + rtc_writel(rtc, LPC32XX_RTC_CTRL, tmp &= ~LPC32XX_RTC_CTRL_CNTR_DIS); + + spin_unlock_irq(&rtc->lock); + + return 0; +} + +static int lpc32xx_rtc_read_alarm(struct device *dev, + struct rtc_wkalrm *wkalrm) +{ + struct lpc32xx_rtc *rtc = dev_get_drvdata(dev); + + rtc_time64_to_tm(rtc_readl(rtc, LPC32XX_RTC_MATCH0), &wkalrm->time); + wkalrm->enabled = rtc->alarm_enabled; + wkalrm->pending = !!(rtc_readl(rtc, LPC32XX_RTC_INTSTAT) & + LPC32XX_RTC_INTSTAT_MATCH0); + + return rtc_valid_tm(&wkalrm->time); +} + +static int lpc32xx_rtc_set_alarm(struct device *dev, + struct rtc_wkalrm *wkalrm) +{ + struct lpc32xx_rtc *rtc = dev_get_drvdata(dev); + unsigned long alarmsecs; + u32 tmp; + + alarmsecs = rtc_tm_to_time64(&wkalrm->time); + + spin_lock_irq(&rtc->lock); + + /* Disable alarm during update */ + tmp = rtc_readl(rtc, LPC32XX_RTC_CTRL); + rtc_writel(rtc, LPC32XX_RTC_CTRL, tmp & ~LPC32XX_RTC_CTRL_MATCH0); + + rtc_writel(rtc, LPC32XX_RTC_MATCH0, alarmsecs); + + rtc->alarm_enabled = wkalrm->enabled; + if (wkalrm->enabled) { + rtc_writel(rtc, LPC32XX_RTC_INTSTAT, + LPC32XX_RTC_INTSTAT_MATCH0); + rtc_writel(rtc, LPC32XX_RTC_CTRL, tmp | + LPC32XX_RTC_CTRL_MATCH0); + } + + spin_unlock_irq(&rtc->lock); + + return 0; +} + +static int lpc32xx_rtc_alarm_irq_enable(struct device *dev, + unsigned int enabled) +{ + struct lpc32xx_rtc *rtc = dev_get_drvdata(dev); + u32 tmp; + + spin_lock_irq(&rtc->lock); + tmp = rtc_readl(rtc, LPC32XX_RTC_CTRL); + + if (enabled) { + rtc->alarm_enabled = 1; + tmp |= LPC32XX_RTC_CTRL_MATCH0; + } else { + rtc->alarm_enabled = 0; + tmp &= ~LPC32XX_RTC_CTRL_MATCH0; + } + + rtc_writel(rtc, LPC32XX_RTC_CTRL, tmp); + spin_unlock_irq(&rtc->lock); + + return 0; +} + +static irqreturn_t lpc32xx_rtc_alarm_interrupt(int irq, void *dev) +{ + struct lpc32xx_rtc *rtc = dev; + + spin_lock(&rtc->lock); + + /* Disable alarm interrupt */ + rtc_writel(rtc, LPC32XX_RTC_CTRL, + rtc_readl(rtc, LPC32XX_RTC_CTRL) & + ~LPC32XX_RTC_CTRL_MATCH0); + rtc->alarm_enabled = 0; + + /* + * Write a large value to the match value so the RTC won't + * keep firing the match status + */ + rtc_writel(rtc, LPC32XX_RTC_MATCH0, 0xFFFFFFFF); + rtc_writel(rtc, LPC32XX_RTC_INTSTAT, LPC32XX_RTC_INTSTAT_MATCH0); + + spin_unlock(&rtc->lock); + + rtc_update_irq(rtc->rtc, 1, RTC_IRQF | RTC_AF); + + return IRQ_HANDLED; +} + +static const struct rtc_class_ops lpc32xx_rtc_ops = { + .read_time = lpc32xx_rtc_read_time, + .set_time = lpc32xx_rtc_set_time, + .read_alarm = lpc32xx_rtc_read_alarm, + .set_alarm = lpc32xx_rtc_set_alarm, + .alarm_irq_enable = lpc32xx_rtc_alarm_irq_enable, +}; + +static int lpc32xx_rtc_probe(struct platform_device *pdev) +{ + struct lpc32xx_rtc *rtc; + int err; + u32 tmp; + + rtc = devm_kzalloc(&pdev->dev, sizeof(*rtc), GFP_KERNEL); + if (unlikely(!rtc)) + return -ENOMEM; + + rtc->rtc_base = devm_platform_ioremap_resource(pdev, 0); + if (IS_ERR(rtc->rtc_base)) + return PTR_ERR(rtc->rtc_base); + + spin_lock_init(&rtc->lock); + + /* + * The RTC is on a separate power domain and can keep it's state + * across a chip power cycle. If the RTC has never been previously + * setup, then set it up now for the first time. + */ + tmp = rtc_readl(rtc, LPC32XX_RTC_CTRL); + if (rtc_readl(rtc, LPC32XX_RTC_KEY) != LPC32XX_RTC_KEY_ONSW_LOADVAL) { + tmp &= ~(LPC32XX_RTC_CTRL_SW_RESET | + LPC32XX_RTC_CTRL_CNTR_DIS | + LPC32XX_RTC_CTRL_MATCH0 | + LPC32XX_RTC_CTRL_MATCH1 | + LPC32XX_RTC_CTRL_ONSW_MATCH0 | + LPC32XX_RTC_CTRL_ONSW_MATCH1 | + LPC32XX_RTC_CTRL_ONSW_FORCE_HI); + rtc_writel(rtc, LPC32XX_RTC_CTRL, tmp); + + /* Clear latched interrupt states */ + rtc_writel(rtc, LPC32XX_RTC_MATCH0, 0xFFFFFFFF); + rtc_writel(rtc, LPC32XX_RTC_INTSTAT, + LPC32XX_RTC_INTSTAT_MATCH0 | + LPC32XX_RTC_INTSTAT_MATCH1 | + LPC32XX_RTC_INTSTAT_ONSW); + + /* Write key value to RTC so it won't reload on reset */ + rtc_writel(rtc, LPC32XX_RTC_KEY, + LPC32XX_RTC_KEY_ONSW_LOADVAL); + } else { + rtc_writel(rtc, LPC32XX_RTC_CTRL, + tmp & ~LPC32XX_RTC_CTRL_MATCH0); + } + + platform_set_drvdata(pdev, rtc); + + rtc->rtc = devm_rtc_allocate_device(&pdev->dev); + if (IS_ERR(rtc->rtc)) + return PTR_ERR(rtc->rtc); + + rtc->rtc->ops = &lpc32xx_rtc_ops; + rtc->rtc->range_max = U32_MAX; + + err = devm_rtc_register_device(rtc->rtc); + if (err) + return err; + + /* + * IRQ is enabled after device registration in case alarm IRQ + * is pending upon suspend exit. + */ + rtc->irq = platform_get_irq(pdev, 0); + if (rtc->irq < 0) { + dev_warn(&pdev->dev, "Can't get interrupt resource\n"); + } else { + if (devm_request_irq(&pdev->dev, rtc->irq, + lpc32xx_rtc_alarm_interrupt, + 0, pdev->name, rtc) < 0) { + dev_warn(&pdev->dev, "Can't request interrupt.\n"); + rtc->irq = -1; + } else { + device_init_wakeup(&pdev->dev, true); + } + } + + return 0; +} + +#ifdef CONFIG_PM +static int lpc32xx_rtc_suspend(struct device *dev) +{ + struct lpc32xx_rtc *rtc = dev_get_drvdata(dev); + + if (rtc->irq >= 0) { + if (device_may_wakeup(dev)) + enable_irq_wake(rtc->irq); + else + disable_irq_wake(rtc->irq); + } + + return 0; +} + +static int lpc32xx_rtc_resume(struct device *dev) +{ + struct lpc32xx_rtc *rtc = dev_get_drvdata(dev); + + if (rtc->irq >= 0 && device_may_wakeup(dev)) + disable_irq_wake(rtc->irq); + + return 0; +} + +/* Unconditionally disable the alarm */ +static int lpc32xx_rtc_freeze(struct device *dev) +{ + struct lpc32xx_rtc *rtc = dev_get_drvdata(dev); + + spin_lock_irq(&rtc->lock); + + rtc_writel(rtc, LPC32XX_RTC_CTRL, + rtc_readl(rtc, LPC32XX_RTC_CTRL) & + ~LPC32XX_RTC_CTRL_MATCH0); + + spin_unlock_irq(&rtc->lock); + + return 0; +} + +static int lpc32xx_rtc_thaw(struct device *dev) +{ + struct lpc32xx_rtc *rtc = dev_get_drvdata(dev); + + if (rtc->alarm_enabled) { + spin_lock_irq(&rtc->lock); + + rtc_writel(rtc, LPC32XX_RTC_CTRL, + rtc_readl(rtc, LPC32XX_RTC_CTRL) | + LPC32XX_RTC_CTRL_MATCH0); + + spin_unlock_irq(&rtc->lock); + } + + return 0; +} + +static const struct dev_pm_ops lpc32xx_rtc_pm_ops = { + .suspend = lpc32xx_rtc_suspend, + .resume = lpc32xx_rtc_resume, + .freeze = lpc32xx_rtc_freeze, + .thaw = lpc32xx_rtc_thaw, + .restore = lpc32xx_rtc_resume +}; + +#define LPC32XX_RTC_PM_OPS (&lpc32xx_rtc_pm_ops) +#else +#define LPC32XX_RTC_PM_OPS NULL +#endif + +#ifdef CONFIG_OF +static const struct of_device_id lpc32xx_rtc_match[] = { + { .compatible = "nxp,lpc3220-rtc" }, + { } +}; +MODULE_DEVICE_TABLE(of, lpc32xx_rtc_match); +#endif + +static struct platform_driver lpc32xx_rtc_driver = { + .probe = lpc32xx_rtc_probe, + .driver = { + .name = "rtc-lpc32xx", + .pm = LPC32XX_RTC_PM_OPS, + .of_match_table = of_match_ptr(lpc32xx_rtc_match), + }, +}; + +module_platform_driver(lpc32xx_rtc_driver); + +MODULE_AUTHOR("Kevin Wells <wellsk40@gmail.com"); +MODULE_DESCRIPTION("RTC driver for the LPC32xx SoC"); +MODULE_LICENSE("GPL"); +MODULE_ALIAS("platform:rtc-lpc32xx"); |
