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authorLinus Torvalds <torvalds@linux-foundation.org>2026-08-30 09:22:00 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2026-08-30 09:22:00 -0700
commit034dd340b08be1f2f0477ad16131d609f9dbd53c (patch)
tree2536f4b2d7893ccd916b5abdf3c454ad6edc03c2 /drivers/rtc/rtc-pxa.c
downloadlinux-stable-034dd340b08be1f2f0477ad16131d609f9dbd53c.tar.gz
linux-stable-034dd340b08be1f2f0477ad16131d609f9dbd53c.zip
Merge tag 'trace-v7.3-2' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-tracegrafted
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
Diffstat (limited to 'drivers/rtc/rtc-pxa.c')
-rw-r--r--drivers/rtc/rtc-pxa.c425
1 files changed, 425 insertions, 0 deletions
diff --git a/drivers/rtc/rtc-pxa.c b/drivers/rtc/rtc-pxa.c
new file mode 100644
index 000000000..62ee6b8f9
--- /dev/null
+++ b/drivers/rtc/rtc-pxa.c
@@ -0,0 +1,425 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * Real Time Clock interface for XScale PXA27x and PXA3xx
+ *
+ * Copyright (C) 2008 Robert Jarzmik
+ */
+
+#include <linux/init.h>
+#include <linux/platform_device.h>
+#include <linux/module.h>
+#include <linux/rtc.h>
+#include <linux/seq_file.h>
+#include <linux/interrupt.h>
+#include <linux/io.h>
+#include <linux/slab.h>
+#include <linux/of.h>
+
+#include "rtc-sa1100.h"
+
+#define RTC_DEF_DIVIDER (32768 - 1)
+#define RTC_DEF_TRIM 0
+#define MAXFREQ_PERIODIC 1000
+
+/*
+ * PXA Registers and bits definitions
+ */
+#define RTSR_PICE (1 << 15) /* Periodic interrupt count enable */
+#define RTSR_PIALE (1 << 14) /* Periodic interrupt Alarm enable */
+#define RTSR_PIAL (1 << 13) /* Periodic interrupt detected */
+#define RTSR_SWALE2 (1 << 11) /* RTC stopwatch alarm2 enable */
+#define RTSR_SWAL2 (1 << 10) /* RTC stopwatch alarm2 detected */
+#define RTSR_SWALE1 (1 << 9) /* RTC stopwatch alarm1 enable */
+#define RTSR_SWAL1 (1 << 8) /* RTC stopwatch alarm1 detected */
+#define RTSR_RDALE2 (1 << 7) /* RTC alarm2 enable */
+#define RTSR_RDAL2 (1 << 6) /* RTC alarm2 detected */
+#define RTSR_RDALE1 (1 << 5) /* RTC alarm1 enable */
+#define RTSR_RDAL1 (1 << 4) /* RTC alarm1 detected */
+#define RTSR_HZE (1 << 3) /* HZ interrupt enable */
+#define RTSR_ALE (1 << 2) /* RTC alarm interrupt enable */
+#define RTSR_HZ (1 << 1) /* HZ rising-edge detected */
+#define RTSR_AL (1 << 0) /* RTC alarm detected */
+#define RTSR_TRIG_MASK (RTSR_AL | RTSR_HZ | RTSR_RDAL1 | RTSR_RDAL2\
+ | RTSR_SWAL1 | RTSR_SWAL2)
+#define RYxR_YEAR_S 9
+#define RYxR_YEAR_MASK (0xfff << RYxR_YEAR_S)
+#define RYxR_MONTH_S 5
+#define RYxR_MONTH_MASK (0xf << RYxR_MONTH_S)
+#define RYxR_DAY_MASK 0x1f
+#define RDxR_WOM_S 20
+#define RDxR_WOM_MASK (0x7 << RDxR_WOM_S)
+#define RDxR_DOW_S 17
+#define RDxR_DOW_MASK (0x7 << RDxR_DOW_S)
+#define RDxR_HOUR_S 12
+#define RDxR_HOUR_MASK (0x1f << RDxR_HOUR_S)
+#define RDxR_MIN_S 6
+#define RDxR_MIN_MASK (0x3f << RDxR_MIN_S)
+#define RDxR_SEC_MASK 0x3f
+
+#define RTSR 0x08
+#define RTTR 0x0c
+#define RDCR 0x10
+#define RYCR 0x14
+#define RDAR1 0x18
+#define RYAR1 0x1c
+#define RTCPICR 0x34
+#define PIAR 0x38
+
+#define rtc_readl(pxa_rtc, reg) \
+ __raw_readl((pxa_rtc)->base + (reg))
+#define rtc_writel(pxa_rtc, reg, value) \
+ __raw_writel((value), (pxa_rtc)->base + (reg))
+
+struct pxa_rtc {
+ struct sa1100_rtc sa1100_rtc;
+ struct resource *ress;
+ void __iomem *base;
+ struct rtc_device *rtc;
+ spinlock_t lock; /* Protects this structure */
+};
+
+
+static u32 ryxr_calc(struct rtc_time *tm)
+{
+ return ((tm->tm_year + 1900) << RYxR_YEAR_S)
+ | ((tm->tm_mon + 1) << RYxR_MONTH_S)
+ | tm->tm_mday;
+}
+
+static u32 rdxr_calc(struct rtc_time *tm)
+{
+ return ((((tm->tm_mday + 6) / 7) << RDxR_WOM_S) & RDxR_WOM_MASK)
+ | (((tm->tm_wday + 1) << RDxR_DOW_S) & RDxR_DOW_MASK)
+ | (tm->tm_hour << RDxR_HOUR_S)
+ | (tm->tm_min << RDxR_MIN_S)
+ | tm->tm_sec;
+}
+
+static void tm_calc(u32 rycr, u32 rdcr, struct rtc_time *tm)
+{
+ tm->tm_year = ((rycr & RYxR_YEAR_MASK) >> RYxR_YEAR_S) - 1900;
+ tm->tm_mon = (((rycr & RYxR_MONTH_MASK) >> RYxR_MONTH_S)) - 1;
+ tm->tm_mday = (rycr & RYxR_DAY_MASK);
+ tm->tm_wday = ((rycr & RDxR_DOW_MASK) >> RDxR_DOW_S) - 1;
+ tm->tm_hour = (rdcr & RDxR_HOUR_MASK) >> RDxR_HOUR_S;
+ tm->tm_min = (rdcr & RDxR_MIN_MASK) >> RDxR_MIN_S;
+ tm->tm_sec = rdcr & RDxR_SEC_MASK;
+}
+
+static void rtsr_clear_bits(struct pxa_rtc *pxa_rtc, u32 mask)
+{
+ u32 rtsr;
+
+ rtsr = rtc_readl(pxa_rtc, RTSR);
+ rtsr &= ~RTSR_TRIG_MASK;
+ rtsr &= ~mask;
+ rtc_writel(pxa_rtc, RTSR, rtsr);
+}
+
+static void rtsr_set_bits(struct pxa_rtc *pxa_rtc, u32 mask)
+{
+ u32 rtsr;
+
+ rtsr = rtc_readl(pxa_rtc, RTSR);
+ rtsr &= ~RTSR_TRIG_MASK;
+ rtsr |= mask;
+ rtc_writel(pxa_rtc, RTSR, rtsr);
+}
+
+static irqreturn_t pxa_rtc_irq(int irq, void *dev_id)
+{
+ struct pxa_rtc *pxa_rtc = dev_get_drvdata(dev_id);
+ u32 rtsr;
+ unsigned long events = 0;
+
+ spin_lock(&pxa_rtc->lock);
+
+ /* clear interrupt sources */
+ rtsr = rtc_readl(pxa_rtc, RTSR);
+ rtc_writel(pxa_rtc, RTSR, rtsr);
+
+ /* temporary disable rtc interrupts */
+ rtsr_clear_bits(pxa_rtc, RTSR_RDALE1 | RTSR_PIALE | RTSR_HZE);
+
+ /* clear alarm interrupt if it has occurred */
+ if (rtsr & RTSR_RDAL1)
+ rtsr &= ~RTSR_RDALE1;
+
+ /* update irq data & counter */
+ if (rtsr & RTSR_RDAL1)
+ events |= RTC_AF | RTC_IRQF;
+ if (rtsr & RTSR_HZ)
+ events |= RTC_UF | RTC_IRQF;
+ if (rtsr & RTSR_PIAL)
+ events |= RTC_PF | RTC_IRQF;
+
+ rtc_update_irq(pxa_rtc->rtc, 1, events);
+
+ /* enable back rtc interrupts */
+ rtc_writel(pxa_rtc, RTSR, rtsr & ~RTSR_TRIG_MASK);
+
+ spin_unlock(&pxa_rtc->lock);
+ return IRQ_HANDLED;
+}
+
+static int pxa_rtc_open(struct device *dev)
+{
+ struct pxa_rtc *pxa_rtc = dev_get_drvdata(dev);
+ int ret;
+
+ ret = request_irq(pxa_rtc->sa1100_rtc.irq_1hz, pxa_rtc_irq, 0,
+ "rtc 1Hz", dev);
+ if (ret < 0) {
+ dev_err(dev, "can't get irq %i, err %d\n",
+ pxa_rtc->sa1100_rtc.irq_1hz, ret);
+ goto err_irq_1Hz;
+ }
+ ret = request_irq(pxa_rtc->sa1100_rtc.irq_alarm, pxa_rtc_irq, 0,
+ "rtc Alrm", dev);
+ if (ret < 0) {
+ dev_err(dev, "can't get irq %i, err %d\n",
+ pxa_rtc->sa1100_rtc.irq_alarm, ret);
+ goto err_irq_Alrm;
+ }
+
+ return 0;
+
+err_irq_Alrm:
+ free_irq(pxa_rtc->sa1100_rtc.irq_1hz, dev);
+err_irq_1Hz:
+ return ret;
+}
+
+static void pxa_rtc_release(struct device *dev)
+{
+ struct pxa_rtc *pxa_rtc = dev_get_drvdata(dev);
+
+ spin_lock_irq(&pxa_rtc->lock);
+ rtsr_clear_bits(pxa_rtc, RTSR_PIALE | RTSR_RDALE1 | RTSR_HZE);
+ spin_unlock_irq(&pxa_rtc->lock);
+
+ free_irq(pxa_rtc->sa1100_rtc.irq_1hz, dev);
+ free_irq(pxa_rtc->sa1100_rtc.irq_alarm, dev);
+}
+
+static int pxa_alarm_irq_enable(struct device *dev, unsigned int enabled)
+{
+ struct pxa_rtc *pxa_rtc = dev_get_drvdata(dev);
+
+ spin_lock_irq(&pxa_rtc->lock);
+
+ if (enabled)
+ rtsr_set_bits(pxa_rtc, RTSR_RDALE1);
+ else
+ rtsr_clear_bits(pxa_rtc, RTSR_RDALE1);
+
+ spin_unlock_irq(&pxa_rtc->lock);
+ return 0;
+}
+
+static int pxa_rtc_read_time(struct device *dev, struct rtc_time *tm)
+{
+ struct pxa_rtc *pxa_rtc = dev_get_drvdata(dev);
+ u32 rycr, rdcr;
+
+ rycr = rtc_readl(pxa_rtc, RYCR);
+ rdcr = rtc_readl(pxa_rtc, RDCR);
+
+ tm_calc(rycr, rdcr, tm);
+ return 0;
+}
+
+static int pxa_rtc_set_time(struct device *dev, struct rtc_time *tm)
+{
+ struct pxa_rtc *pxa_rtc = dev_get_drvdata(dev);
+
+ rtc_writel(pxa_rtc, RYCR, ryxr_calc(tm));
+ rtc_writel(pxa_rtc, RDCR, rdxr_calc(tm));
+
+ return 0;
+}
+
+static int pxa_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *alrm)
+{
+ struct pxa_rtc *pxa_rtc = dev_get_drvdata(dev);
+ u32 rtsr, ryar, rdar;
+
+ ryar = rtc_readl(pxa_rtc, RYAR1);
+ rdar = rtc_readl(pxa_rtc, RDAR1);
+ tm_calc(ryar, rdar, &alrm->time);
+
+ rtsr = rtc_readl(pxa_rtc, RTSR);
+ alrm->enabled = (rtsr & RTSR_RDALE1) ? 1 : 0;
+ alrm->pending = (rtsr & RTSR_RDAL1) ? 1 : 0;
+ return 0;
+}
+
+static int pxa_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alrm)
+{
+ struct pxa_rtc *pxa_rtc = dev_get_drvdata(dev);
+ u32 rtsr;
+
+ spin_lock_irq(&pxa_rtc->lock);
+
+ rtc_writel(pxa_rtc, RYAR1, ryxr_calc(&alrm->time));
+ rtc_writel(pxa_rtc, RDAR1, rdxr_calc(&alrm->time));
+
+ rtsr = rtc_readl(pxa_rtc, RTSR);
+ if (alrm->enabled)
+ rtsr |= RTSR_RDALE1;
+ else
+ rtsr &= ~RTSR_RDALE1;
+ rtc_writel(pxa_rtc, RTSR, rtsr);
+
+ spin_unlock_irq(&pxa_rtc->lock);
+
+ return 0;
+}
+
+static int pxa_rtc_proc(struct device *dev, struct seq_file *seq)
+{
+ struct pxa_rtc *pxa_rtc = dev_get_drvdata(dev);
+
+ seq_printf(seq, "trim/divider\t: 0x%08x\n", rtc_readl(pxa_rtc, RTTR));
+ seq_printf(seq, "update_IRQ\t: %s\n",
+ (rtc_readl(pxa_rtc, RTSR) & RTSR_HZE) ? "yes" : "no");
+ seq_printf(seq, "periodic_IRQ\t: %s\n",
+ (rtc_readl(pxa_rtc, RTSR) & RTSR_PIALE) ? "yes" : "no");
+ seq_printf(seq, "periodic_freq\t: %u\n", rtc_readl(pxa_rtc, PIAR));
+
+ return 0;
+}
+
+static const struct rtc_class_ops pxa_rtc_ops = {
+ .read_time = pxa_rtc_read_time,
+ .set_time = pxa_rtc_set_time,
+ .read_alarm = pxa_rtc_read_alarm,
+ .set_alarm = pxa_rtc_set_alarm,
+ .alarm_irq_enable = pxa_alarm_irq_enable,
+ .proc = pxa_rtc_proc,
+};
+
+static int __init pxa_rtc_probe(struct platform_device *pdev)
+{
+ struct device *dev = &pdev->dev;
+ struct pxa_rtc *pxa_rtc;
+ struct sa1100_rtc *sa1100_rtc;
+ int ret;
+
+ pxa_rtc = devm_kzalloc(dev, sizeof(*pxa_rtc), GFP_KERNEL);
+ if (!pxa_rtc)
+ return -ENOMEM;
+ sa1100_rtc = &pxa_rtc->sa1100_rtc;
+
+ spin_lock_init(&pxa_rtc->lock);
+ platform_set_drvdata(pdev, pxa_rtc);
+
+ pxa_rtc->ress = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+ if (!pxa_rtc->ress) {
+ dev_err(dev, "No I/O memory resource defined\n");
+ return -ENXIO;
+ }
+
+ sa1100_rtc->irq_1hz = platform_get_irq(pdev, 0);
+ if (sa1100_rtc->irq_1hz < 0)
+ return -ENXIO;
+ sa1100_rtc->irq_alarm = platform_get_irq(pdev, 1);
+ if (sa1100_rtc->irq_alarm < 0)
+ return -ENXIO;
+
+ sa1100_rtc->rtc = devm_rtc_allocate_device(&pdev->dev);
+ if (IS_ERR(sa1100_rtc->rtc))
+ return PTR_ERR(sa1100_rtc->rtc);
+
+ pxa_rtc->base = devm_ioremap(dev, pxa_rtc->ress->start,
+ resource_size(pxa_rtc->ress));
+ if (!pxa_rtc->base) {
+ dev_err(dev, "Unable to map pxa RTC I/O memory\n");
+ return -ENOMEM;
+ }
+
+ pxa_rtc_open(dev);
+
+ sa1100_rtc->rcnr = pxa_rtc->base + 0x0;
+ sa1100_rtc->rtsr = pxa_rtc->base + 0x8;
+ sa1100_rtc->rtar = pxa_rtc->base + 0x4;
+ sa1100_rtc->rttr = pxa_rtc->base + 0xc;
+ ret = sa1100_rtc_init(pdev, sa1100_rtc);
+ if (ret) {
+ dev_err(dev, "Unable to init SA1100 RTC sub-device\n");
+ return ret;
+ }
+
+ rtsr_clear_bits(pxa_rtc, RTSR_PIALE | RTSR_RDALE1 | RTSR_HZE);
+
+ pxa_rtc->rtc = devm_rtc_device_register(&pdev->dev, "pxa-rtc",
+ &pxa_rtc_ops, THIS_MODULE);
+ if (IS_ERR(pxa_rtc->rtc)) {
+ ret = PTR_ERR(pxa_rtc->rtc);
+ dev_err(dev, "Failed to register RTC device -> %d\n", ret);
+ return ret;
+ }
+
+ device_init_wakeup(dev, true);
+
+ return 0;
+}
+
+static void __exit pxa_rtc_remove(struct platform_device *pdev)
+{
+ struct device *dev = &pdev->dev;
+
+ pxa_rtc_release(dev);
+}
+
+#ifdef CONFIG_OF
+static const struct of_device_id pxa_rtc_dt_ids[] = {
+ { .compatible = "marvell,pxa-rtc" },
+ {}
+};
+MODULE_DEVICE_TABLE(of, pxa_rtc_dt_ids);
+#endif
+
+#ifdef CONFIG_PM_SLEEP
+static int pxa_rtc_suspend(struct device *dev)
+{
+ struct pxa_rtc *pxa_rtc = dev_get_drvdata(dev);
+
+ if (device_may_wakeup(dev))
+ enable_irq_wake(pxa_rtc->sa1100_rtc.irq_alarm);
+ return 0;
+}
+
+static int pxa_rtc_resume(struct device *dev)
+{
+ struct pxa_rtc *pxa_rtc = dev_get_drvdata(dev);
+
+ if (device_may_wakeup(dev))
+ disable_irq_wake(pxa_rtc->sa1100_rtc.irq_alarm);
+ return 0;
+}
+#endif
+
+static SIMPLE_DEV_PM_OPS(pxa_rtc_pm_ops, pxa_rtc_suspend, pxa_rtc_resume);
+
+/*
+ * pxa_rtc_remove() lives in .exit.text. For drivers registered via
+ * module_platform_driver_probe() this is ok because they cannot get unbound at
+ * runtime. So mark the driver struct with __refdata to prevent modpost
+ * triggering a section mismatch warning.
+ */
+static struct platform_driver pxa_rtc_driver __refdata = {
+ .remove = __exit_p(pxa_rtc_remove),
+ .driver = {
+ .name = "pxa-rtc",
+ .of_match_table = of_match_ptr(pxa_rtc_dt_ids),
+ .pm = &pxa_rtc_pm_ops,
+ },
+};
+
+module_platform_driver_probe(pxa_rtc_driver, pxa_rtc_probe);
+
+MODULE_AUTHOR("Robert Jarzmik <robert.jarzmik@free.fr>");
+MODULE_DESCRIPTION("PXA27x/PXA3xx Realtime Clock Driver (RTC)");
+MODULE_LICENSE("GPL");
+MODULE_ALIAS("platform:pxa-rtc");