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authorLinus Torvalds <torvalds@linux-foundation.org>2026-10-02 12:17:24 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2026-10-02 12:17:24 -0700
commit3f1fe48a36b0b6722dc3fd421d93512bac138e9a (patch)
treeb767d7f6e26bc64334d3f14f8422d187239dc45d /drivers/rtc/rtc-bq4802.c
downloadlinux-stable-3f1fe48a36b0b6722dc3fd421d93512bac138e9a.tar.gz
linux-stable-3f1fe48a36b0b6722dc3fd421d93512bac138e9a.zip
Merge tag 'io_uring-7.3-20261002' of git://git.kernel.org/pub/scm/linux/kernel/git/axboe/linuxgrafted
Pull io_uring fixes from Jens Axboe: - Fix a task_work add use-after-free with SQPOLL. The sqpoll thread could pop and complete the last request while io_req_normal_work_add() was still looking at them after the mpscq push. Use the same approach as DEFER_TASKRUN to protect from that, holding an RCU read lock across the add, and have exit wait for an RCU grace period for SQPOLL rings as well. - CQE32 ring fixes: correct the free entry check for 32b CQEs, zero the big_cqe for aux CQEs, and only post the dummy skip CQE on CQE_MIXED rings - Mark the source filter table as COW when cloning bpf filters, so registering another filter on the source doesn't modify the shared table in place - Initialize the task context before running the BPF loop - Requeue zcrx multishot receives stopped by a local resource - End a TX_TIMESTAMP multishot cmd when the CQ is full (lollipopkit) * tag 'io_uring-7.3-20261002' of git://git.kernel.org/pub/scm/linux/kernel/git/axboe/linux: io_uring: fix task_work add use-after-free with SQPOLL io_uring/cmd_net: end TX_TIMESTAMP multishot when the CQ is full io_uring/zcrx: requeue multishot receives stopped by a local resource io_uring: initialize task context before running the BPF loop io_uring: zero big_cqe for aux CQEs on CQE32 rings io_uring: fix free entry check for 32b CQEs on CQE32 rings io_uring: only post the dummy skip CQE on CQE_MIXED rings io_uring/bpf_filter: mark source as COW when cloning filters
Diffstat (limited to 'drivers/rtc/rtc-bq4802.c')
-rw-r--r--drivers/rtc/rtc-bq4802.c202
1 files changed, 202 insertions, 0 deletions
diff --git a/drivers/rtc/rtc-bq4802.c b/drivers/rtc/rtc-bq4802.c
new file mode 100644
index 000000000..472e75668
--- /dev/null
+++ b/drivers/rtc/rtc-bq4802.c
@@ -0,0 +1,202 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/* rtc-bq4802.c: TI BQ4802 RTC driver.
+ *
+ * Copyright (C) 2008 David S. Miller <davem@davemloft.net>
+ */
+
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/io.h>
+#include <linux/platform_device.h>
+#include <linux/rtc.h>
+#include <linux/bcd.h>
+#include <linux/slab.h>
+
+MODULE_AUTHOR("David S. Miller <davem@davemloft.net>");
+MODULE_DESCRIPTION("TI BQ4802 RTC driver");
+MODULE_LICENSE("GPL");
+
+struct bq4802 {
+ void __iomem *regs;
+ unsigned long ioport;
+ struct rtc_device *rtc;
+ spinlock_t lock;
+ struct resource *r;
+ u8 (*read)(struct bq4802 *, int);
+ void (*write)(struct bq4802 *, int, u8);
+};
+
+static u8 bq4802_read_io(struct bq4802 *p, int off)
+{
+ return inb(p->ioport + off);
+}
+
+static void bq4802_write_io(struct bq4802 *p, int off, u8 val)
+{
+ outb(val, p->ioport + off);
+}
+
+static u8 bq4802_read_mem(struct bq4802 *p, int off)
+{
+ return readb(p->regs + off);
+}
+
+static void bq4802_write_mem(struct bq4802 *p, int off, u8 val)
+{
+ writeb(val, p->regs + off);
+}
+
+static int bq4802_read_time(struct device *dev, struct rtc_time *tm)
+{
+ struct bq4802 *p = dev_get_drvdata(dev);
+ unsigned long flags;
+ unsigned int century;
+ u8 val;
+
+ spin_lock_irqsave(&p->lock, flags);
+
+ val = p->read(p, 0x0e);
+ p->write(p, 0xe, val | 0x08);
+
+ tm->tm_sec = p->read(p, 0x00);
+ tm->tm_min = p->read(p, 0x02);
+ tm->tm_hour = p->read(p, 0x04);
+ tm->tm_mday = p->read(p, 0x06);
+ tm->tm_mon = p->read(p, 0x09);
+ tm->tm_year = p->read(p, 0x0a);
+ tm->tm_wday = p->read(p, 0x08);
+ century = p->read(p, 0x0f);
+
+ p->write(p, 0x0e, val);
+
+ spin_unlock_irqrestore(&p->lock, flags);
+
+ 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);
+ tm->tm_year = bcd2bin(tm->tm_year);
+ tm->tm_wday = bcd2bin(tm->tm_wday);
+ century = bcd2bin(century);
+
+ tm->tm_year += (century * 100);
+ tm->tm_year -= 1900;
+
+ tm->tm_mon--;
+
+ return 0;
+}
+
+static int bq4802_set_time(struct device *dev, struct rtc_time *tm)
+{
+ struct bq4802 *p = dev_get_drvdata(dev);
+ u8 sec, min, hrs, day, mon, yrs, century, val;
+ unsigned long flags;
+ unsigned int year;
+
+ year = tm->tm_year + 1900;
+ century = year / 100;
+ yrs = year % 100;
+
+ mon = tm->tm_mon + 1; /* tm_mon starts at zero */
+ day = tm->tm_mday;
+ hrs = tm->tm_hour;
+ min = tm->tm_min;
+ sec = tm->tm_sec;
+
+ sec = bin2bcd(sec);
+ min = bin2bcd(min);
+ hrs = bin2bcd(hrs);
+ day = bin2bcd(day);
+ mon = bin2bcd(mon);
+ yrs = bin2bcd(yrs);
+ century = bin2bcd(century);
+
+ spin_lock_irqsave(&p->lock, flags);
+
+ val = p->read(p, 0x0e);
+ p->write(p, 0x0e, val | 0x08);
+
+ p->write(p, 0x00, sec);
+ p->write(p, 0x02, min);
+ p->write(p, 0x04, hrs);
+ p->write(p, 0x06, day);
+ p->write(p, 0x09, mon);
+ p->write(p, 0x0a, yrs);
+ p->write(p, 0x0f, century);
+
+ p->write(p, 0x0e, val);
+
+ spin_unlock_irqrestore(&p->lock, flags);
+
+ return 0;
+}
+
+static const struct rtc_class_ops bq4802_ops = {
+ .read_time = bq4802_read_time,
+ .set_time = bq4802_set_time,
+};
+
+static int bq4802_probe(struct platform_device *pdev)
+{
+ struct bq4802 *p = devm_kzalloc(&pdev->dev, sizeof(*p), GFP_KERNEL);
+ int err = -ENOMEM;
+
+ if (!p)
+ goto out;
+
+ spin_lock_init(&p->lock);
+
+ p->r = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+ if (!p->r) {
+ p->r = platform_get_resource(pdev, IORESOURCE_IO, 0);
+ err = -EINVAL;
+ if (!p->r)
+ goto out;
+ }
+ if (p->r->flags & IORESOURCE_IO) {
+ p->ioport = p->r->start;
+ p->read = bq4802_read_io;
+ p->write = bq4802_write_io;
+ } else if (p->r->flags & IORESOURCE_MEM) {
+ p->regs = devm_ioremap(&pdev->dev, p->r->start,
+ resource_size(p->r));
+ if (!p->regs){
+ err = -ENOMEM;
+ goto out;
+ }
+ p->read = bq4802_read_mem;
+ p->write = bq4802_write_mem;
+ } else {
+ err = -EINVAL;
+ goto out;
+ }
+
+ platform_set_drvdata(pdev, p);
+
+ p->rtc = devm_rtc_device_register(&pdev->dev, "bq4802",
+ &bq4802_ops, THIS_MODULE);
+ if (IS_ERR(p->rtc)) {
+ err = PTR_ERR(p->rtc);
+ goto out;
+ }
+
+ err = 0;
+out:
+ return err;
+
+}
+
+/* work with hotplug and coldplug */
+MODULE_ALIAS("platform:rtc-bq4802");
+
+static struct platform_driver bq4802_driver = {
+ .driver = {
+ .name = "rtc-bq4802",
+ },
+ .probe = bq4802_probe,
+};
+
+module_platform_driver(bq4802_driver);