From 034dd340b08be1f2f0477ad16131d609f9dbd53c Mon Sep 17 00:00:00 2001 From: Linus Torvalds Date: Sun, 30 Aug 2026 09:22:00 -0700 Subject: Merge tag 'trace-v7.3-2' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace Pull tracing fixes from Steven Rostedt: - Fix error output of boot instance creation failure Currently if a boot instance creation fails, instead of printing out the name of the instance that failed, it prints "(null)". That is because it prints "cur_str" that had already been processed by strsep(). Print the saved name instead. While at it, print the error code of the failure. - Fix use-after-free for same named historgrams Histograms can be named so that they can be used in multiple events. But if the named histogram has a variable attached, the second event that uses the named histogram which duplicates it and needs to free the original after duplication leaves the old variable in place and still visible. If another histogram uses than variable, it will use the stale one which will try to reference the freed duplicate histogram and crash the kernel. Free the duplicate variables along with the duplicated histogram data. - Check return value of kthread_run() in event self test The events self tests uses a kthread for testing but does not check if it succeeded in creating a kthread. If the kthread creation were to fail, the code will still try to call kthread_stop() on the error returned. - Fix race between reading trace_pipe and updating subbuffer size If a user is reading the trace_pipe file at the same time they update the ring buffer sub-buffer size, can cause the trace_pipe read to read stale data. Add trace_access_lock() around updating the ring buffer sub-buffer size. - Fix eventfs_inode on failure path in creation of the events directory In the creation of the "events" directory, if after allocating the eventfs_inode a failure is detected, it calls cleanup_ei() which calls free_ei(). The free_ei() will test if eventfs_inode being freed has no children. It is a bug if it does. But on the failure case of the creation of the "events" directory, the children lists have not yet been initialized and the free will trigger a warning because list_empty() on an uninitialized list returns false. Move the initialization into init_ei() where it makes more sense and makes sure that a created eventfs_inode has its lists initialized upon creation. - Check return value of kthread_run() in ftrace direct sample code The sample code that shows how to use the ftrace direct calls does not test the return of kthread_run() to see if it succeeds. Return a failure if the kthread_run() doesn't succeed. - Clear user events state on fork in case of alloc failure On fork, the child gets a pointer to the parent's user events state. It makes a copy of it then updates the child's pointer to it. But if the allocation fails, the duplication function leaves the child with a pointer to its parent's descriptor. When the child cleans up its data, it will free the parent's descriptor while the parent is still using it. In the duplication function, set the child's user_event_mm to NULL before testing if the allocation succeeded, and when it exits it will not free the parent's descriptor. - Fix retry exhaustion in simple ring buffer reader swap simple_ring_buffer_swap_reader_page() starts with retry set to 8 and post-decrements it only after a failed link replacement. On the final attempt, a successful replacement leaves retry at zero, while a failed replacement leaves it at -1. But the check for success expects the retry value to be non-zero and exits with an error on zero. This is the opposite result. Fix it. - Fail nicely when the remote swap_reader_page() returns an error Currently, if the swap_reader_page() of a remote buffer fails, it triggers a WARN_ON_ONCE() and continues normally. Instead, have it exit with an error and a pr_warn() print instead of a full WARNING. * tag 'trace-v7.3-2' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace: ring-buffer: Stop remote reader update when page swap fails tracing: Fix retry exhaustion in simple ring buffer reader swap tracing/user_events: Clear copied tracing state before fork duplication samples/ftrace: Fix kthread_stop() on ERR_PTR in ftrace-direct-multi-modify samples/ftrace: Fix kthread_stop() on ERR_PTR in ftrace-direct-modify eventfs: Initialize ei->children and ei->list in init_ei() tracing: Fix use-after-free in trace_pipe read on sub-buffer order change tracing: Fix crash passing ERR_PTR to kthread_stop() tracing: Fix use-after-free with same-name named triggers tracing: Fix logged instance name on creation failure --- drivers/rtc/rtc-mt7622.c | 408 +++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 408 insertions(+) create mode 100644 drivers/rtc/rtc-mt7622.c (limited to 'drivers/rtc/rtc-mt7622.c') diff --git a/drivers/rtc/rtc-mt7622.c b/drivers/rtc/rtc-mt7622.c new file mode 100644 index 000000000..9e17dd09d --- /dev/null +++ b/drivers/rtc/rtc-mt7622.c @@ -0,0 +1,408 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * Driver for MediaTek SoC based RTC + * + * Copyright (C) 2017 Sean Wang + */ + +#include +#include +#include +#include +#include +#include + +#define MTK_RTC_DEV KBUILD_MODNAME + +#define MTK_RTC_PWRCHK1 0x4 +#define RTC_PWRCHK1_MAGIC 0xc6 + +#define MTK_RTC_PWRCHK2 0x8 +#define RTC_PWRCHK2_MAGIC 0x9a + +#define MTK_RTC_KEY 0xc +#define RTC_KEY_MAGIC 0x59 + +#define MTK_RTC_PROT1 0x10 +#define RTC_PROT1_MAGIC 0xa3 + +#define MTK_RTC_PROT2 0x14 +#define RTC_PROT2_MAGIC 0x57 + +#define MTK_RTC_PROT3 0x18 +#define RTC_PROT3_MAGIC 0x67 + +#define MTK_RTC_PROT4 0x1c +#define RTC_PROT4_MAGIC 0xd2 + +#define MTK_RTC_CTL 0x20 +#define RTC_RC_STOP BIT(0) + +#define MTK_RTC_DEBNCE 0x2c +#define RTC_DEBNCE_MASK GENMASK(2, 0) + +#define MTK_RTC_INT 0x30 +#define RTC_INT_AL_STA BIT(4) + +/* + * Ranges from 0x40 to 0x78 provide RTC time setup for year, month, + * day of month, day of week, hour, minute and second. + */ +#define MTK_RTC_TREG(_t, _f) (0x40 + (0x4 * (_f)) + ((_t) * 0x20)) + +#define MTK_RTC_AL_CTL 0x7c +#define RTC_AL_EN BIT(0) +#define RTC_AL_ALL GENMASK(7, 0) + +/* + * The offset is used in the translation for the year between in struct + * rtc_time and in hardware register MTK_RTC_TREG(x,MTK_YEA) + */ +#define MTK_RTC_TM_YR_OFFSET 100 + +/* + * The lowest value for the valid tm_year. RTC hardware would take incorrectly + * tm_year 100 as not a leap year and thus it is also required being excluded + * from the valid options. + */ +#define MTK_RTC_TM_YR_L (MTK_RTC_TM_YR_OFFSET + 1) + +/* + * The most year the RTC can hold is 99 and the next to 99 in year register + * would be wraparound to 0, for MT7622. + */ +#define MTK_RTC_HW_YR_LIMIT 99 + +/* The highest value for the valid tm_year */ +#define MTK_RTC_TM_YR_H (MTK_RTC_TM_YR_OFFSET + MTK_RTC_HW_YR_LIMIT) + +/* Simple macro helps to check whether the hardware supports the tm_year */ +#define MTK_RTC_TM_YR_VALID(_y) ((_y) >= MTK_RTC_TM_YR_L && \ + (_y) <= MTK_RTC_TM_YR_H) + +/* Types of the function the RTC provides are time counter and alarm. */ +enum { + MTK_TC, + MTK_AL, +}; + +/* Indexes are used for the pointer to relevant registers in MTK_RTC_TREG */ +enum { + MTK_YEA, + MTK_MON, + MTK_DOM, + MTK_DOW, + MTK_HOU, + MTK_MIN, + MTK_SEC +}; + +struct mtk_rtc { + struct rtc_device *rtc; + void __iomem *base; + int irq; + struct clk *clk; +}; + +static void mtk_w32(struct mtk_rtc *rtc, u32 reg, u32 val) +{ + writel_relaxed(val, rtc->base + reg); +} + +static u32 mtk_r32(struct mtk_rtc *rtc, u32 reg) +{ + return readl_relaxed(rtc->base + reg); +} + +static void mtk_rmw(struct mtk_rtc *rtc, u32 reg, u32 mask, u32 set) +{ + u32 val; + + val = mtk_r32(rtc, reg); + val &= ~mask; + val |= set; + mtk_w32(rtc, reg, val); +} + +static void mtk_set(struct mtk_rtc *rtc, u32 reg, u32 val) +{ + mtk_rmw(rtc, reg, 0, val); +} + +static void mtk_clr(struct mtk_rtc *rtc, u32 reg, u32 val) +{ + mtk_rmw(rtc, reg, val, 0); +} + +static void mtk_rtc_hw_init(struct mtk_rtc *hw) +{ + /* The setup of the init sequence is for allowing RTC got to work */ + mtk_w32(hw, MTK_RTC_PWRCHK1, RTC_PWRCHK1_MAGIC); + mtk_w32(hw, MTK_RTC_PWRCHK2, RTC_PWRCHK2_MAGIC); + mtk_w32(hw, MTK_RTC_KEY, RTC_KEY_MAGIC); + mtk_w32(hw, MTK_RTC_PROT1, RTC_PROT1_MAGIC); + mtk_w32(hw, MTK_RTC_PROT2, RTC_PROT2_MAGIC); + mtk_w32(hw, MTK_RTC_PROT3, RTC_PROT3_MAGIC); + mtk_w32(hw, MTK_RTC_PROT4, RTC_PROT4_MAGIC); + mtk_rmw(hw, MTK_RTC_DEBNCE, RTC_DEBNCE_MASK, 0); + mtk_clr(hw, MTK_RTC_CTL, RTC_RC_STOP); +} + +static void mtk_rtc_get_alarm_or_time(struct mtk_rtc *hw, struct rtc_time *tm, + int time_alarm) +{ + u32 year, mon, mday, wday, hour, min, sec; + + /* + * Read again until the field of the second is not changed which + * ensures all fields in the consistent state. Note that MTK_SEC must + * be read first. In this way, it guarantees the others remain not + * changed when the results for two MTK_SEC consecutive reads are same. + */ + do { + sec = mtk_r32(hw, MTK_RTC_TREG(time_alarm, MTK_SEC)); + min = mtk_r32(hw, MTK_RTC_TREG(time_alarm, MTK_MIN)); + hour = mtk_r32(hw, MTK_RTC_TREG(time_alarm, MTK_HOU)); + wday = mtk_r32(hw, MTK_RTC_TREG(time_alarm, MTK_DOW)); + mday = mtk_r32(hw, MTK_RTC_TREG(time_alarm, MTK_DOM)); + mon = mtk_r32(hw, MTK_RTC_TREG(time_alarm, MTK_MON)); + year = mtk_r32(hw, MTK_RTC_TREG(time_alarm, MTK_YEA)); + } while (sec != mtk_r32(hw, MTK_RTC_TREG(time_alarm, MTK_SEC))); + + tm->tm_sec = sec; + tm->tm_min = min; + tm->tm_hour = hour; + tm->tm_wday = wday; + tm->tm_mday = mday; + tm->tm_mon = mon - 1; + + /* Rebase to the absolute year which userspace queries */ + tm->tm_year = year + MTK_RTC_TM_YR_OFFSET; +} + +static void mtk_rtc_set_alarm_or_time(struct mtk_rtc *hw, struct rtc_time *tm, + int time_alarm) +{ + u32 year; + + /* Rebase to the relative year which RTC hardware requires */ + year = tm->tm_year - MTK_RTC_TM_YR_OFFSET; + + mtk_w32(hw, MTK_RTC_TREG(time_alarm, MTK_YEA), year); + mtk_w32(hw, MTK_RTC_TREG(time_alarm, MTK_MON), tm->tm_mon + 1); + mtk_w32(hw, MTK_RTC_TREG(time_alarm, MTK_DOW), tm->tm_wday); + mtk_w32(hw, MTK_RTC_TREG(time_alarm, MTK_DOM), tm->tm_mday); + mtk_w32(hw, MTK_RTC_TREG(time_alarm, MTK_HOU), tm->tm_hour); + mtk_w32(hw, MTK_RTC_TREG(time_alarm, MTK_MIN), tm->tm_min); + mtk_w32(hw, MTK_RTC_TREG(time_alarm, MTK_SEC), tm->tm_sec); +} + +static irqreturn_t mtk_rtc_alarmirq(int irq, void *id) +{ + struct mtk_rtc *hw = (struct mtk_rtc *)id; + u32 irq_sta; + + irq_sta = mtk_r32(hw, MTK_RTC_INT); + if (irq_sta & RTC_INT_AL_STA) { + /* Stop alarm also implicitly disables the alarm interrupt */ + mtk_w32(hw, MTK_RTC_AL_CTL, 0); + rtc_update_irq(hw->rtc, 1, RTC_IRQF | RTC_AF); + + /* Ack alarm interrupt status */ + mtk_w32(hw, MTK_RTC_INT, RTC_INT_AL_STA); + return IRQ_HANDLED; + } + + return IRQ_NONE; +} + +static int mtk_rtc_gettime(struct device *dev, struct rtc_time *tm) +{ + struct mtk_rtc *hw = dev_get_drvdata(dev); + + mtk_rtc_get_alarm_or_time(hw, tm, MTK_TC); + + return 0; +} + +static int mtk_rtc_settime(struct device *dev, struct rtc_time *tm) +{ + struct mtk_rtc *hw = dev_get_drvdata(dev); + + if (!MTK_RTC_TM_YR_VALID(tm->tm_year)) + return -EINVAL; + + /* Stop time counter before setting a new one*/ + mtk_set(hw, MTK_RTC_CTL, RTC_RC_STOP); + + mtk_rtc_set_alarm_or_time(hw, tm, MTK_TC); + + /* Restart the time counter */ + mtk_clr(hw, MTK_RTC_CTL, RTC_RC_STOP); + + return 0; +} + +static int mtk_rtc_getalarm(struct device *dev, struct rtc_wkalrm *wkalrm) +{ + struct mtk_rtc *hw = dev_get_drvdata(dev); + struct rtc_time *alrm_tm = &wkalrm->time; + + mtk_rtc_get_alarm_or_time(hw, alrm_tm, MTK_AL); + + wkalrm->enabled = !!(mtk_r32(hw, MTK_RTC_AL_CTL) & RTC_AL_EN); + wkalrm->pending = !!(mtk_r32(hw, MTK_RTC_INT) & RTC_INT_AL_STA); + + return 0; +} + +static int mtk_rtc_setalarm(struct device *dev, struct rtc_wkalrm *wkalrm) +{ + struct mtk_rtc *hw = dev_get_drvdata(dev); + struct rtc_time *alrm_tm = &wkalrm->time; + + if (!MTK_RTC_TM_YR_VALID(alrm_tm->tm_year)) + return -EINVAL; + + /* + * Stop the alarm also implicitly including disables interrupt before + * setting a new one. + */ + mtk_clr(hw, MTK_RTC_AL_CTL, RTC_AL_EN); + + /* + * Avoid contention between mtk_rtc_setalarm and IRQ handler so that + * disabling the interrupt and awaiting for pending IRQ handler to + * complete. + */ + synchronize_irq(hw->irq); + + mtk_rtc_set_alarm_or_time(hw, alrm_tm, MTK_AL); + + /* Restart the alarm with the new setup */ + mtk_w32(hw, MTK_RTC_AL_CTL, RTC_AL_ALL); + + return 0; +} + +static const struct rtc_class_ops mtk_rtc_ops = { + .read_time = mtk_rtc_gettime, + .set_time = mtk_rtc_settime, + .read_alarm = mtk_rtc_getalarm, + .set_alarm = mtk_rtc_setalarm, +}; + +static const struct of_device_id mtk_rtc_match[] = { + { .compatible = "mediatek,mt7622-rtc" }, + { .compatible = "mediatek,soc-rtc" }, + {}, +}; +MODULE_DEVICE_TABLE(of, mtk_rtc_match); + +static int mtk_rtc_probe(struct platform_device *pdev) +{ + struct mtk_rtc *hw; + int ret; + + hw = devm_kzalloc(&pdev->dev, sizeof(*hw), GFP_KERNEL); + if (!hw) + return -ENOMEM; + + platform_set_drvdata(pdev, hw); + + hw->base = devm_platform_ioremap_resource(pdev, 0); + if (IS_ERR(hw->base)) + return PTR_ERR(hw->base); + + hw->clk = devm_clk_get(&pdev->dev, "rtc"); + if (IS_ERR(hw->clk)) { + dev_err(&pdev->dev, "No clock\n"); + return PTR_ERR(hw->clk); + } + + ret = clk_prepare_enable(hw->clk); + if (ret) + return ret; + + hw->irq = platform_get_irq(pdev, 0); + if (hw->irq < 0) { + ret = hw->irq; + goto err; + } + + ret = devm_request_irq(&pdev->dev, hw->irq, mtk_rtc_alarmirq, + 0, dev_name(&pdev->dev), hw); + if (ret) { + dev_err(&pdev->dev, "Can't request IRQ\n"); + goto err; + } + + mtk_rtc_hw_init(hw); + + device_init_wakeup(&pdev->dev, true); + + hw->rtc = devm_rtc_device_register(&pdev->dev, pdev->name, + &mtk_rtc_ops, THIS_MODULE); + if (IS_ERR(hw->rtc)) { + ret = PTR_ERR(hw->rtc); + dev_err(&pdev->dev, "Unable to register device\n"); + goto err; + } + + return 0; +err: + clk_disable_unprepare(hw->clk); + + return ret; +} + +static void mtk_rtc_remove(struct platform_device *pdev) +{ + struct mtk_rtc *hw = platform_get_drvdata(pdev); + + clk_disable_unprepare(hw->clk); +} + +#ifdef CONFIG_PM_SLEEP +static int mtk_rtc_suspend(struct device *dev) +{ + struct mtk_rtc *hw = dev_get_drvdata(dev); + + if (device_may_wakeup(dev)) + enable_irq_wake(hw->irq); + + return 0; +} + +static int mtk_rtc_resume(struct device *dev) +{ + struct mtk_rtc *hw = dev_get_drvdata(dev); + + if (device_may_wakeup(dev)) + disable_irq_wake(hw->irq); + + return 0; +} + +static SIMPLE_DEV_PM_OPS(mtk_rtc_pm_ops, mtk_rtc_suspend, mtk_rtc_resume); + +#define MTK_RTC_PM_OPS (&mtk_rtc_pm_ops) +#else /* CONFIG_PM */ +#define MTK_RTC_PM_OPS NULL +#endif /* CONFIG_PM */ + +static struct platform_driver mtk_rtc_driver = { + .probe = mtk_rtc_probe, + .remove = mtk_rtc_remove, + .driver = { + .name = MTK_RTC_DEV, + .of_match_table = mtk_rtc_match, + .pm = MTK_RTC_PM_OPS, + }, +}; + +module_platform_driver(mtk_rtc_driver); + +MODULE_DESCRIPTION("MediaTek SoC based RTC Driver"); +MODULE_AUTHOR("Sean Wang "); +MODULE_LICENSE("GPL"); -- cgit v1.3.1