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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-ep93xx.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-ep93xx.c')
-rw-r--r--drivers/rtc/rtc-ep93xx.c170
1 files changed, 170 insertions, 0 deletions
diff --git a/drivers/rtc/rtc-ep93xx.c b/drivers/rtc/rtc-ep93xx.c
new file mode 100644
index 000000000..507c9f220
--- /dev/null
+++ b/drivers/rtc/rtc-ep93xx.c
@@ -0,0 +1,170 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * A driver for the RTC embedded in the Cirrus Logic EP93XX processors
+ * Copyright (c) 2006 Tower Technologies
+ *
+ * Author: Alessandro Zummo <a.zummo@towertech.it>
+ */
+
+#include <linux/module.h>
+#include <linux/rtc.h>
+#include <linux/platform_device.h>
+#include <linux/io.h>
+#include <linux/gfp.h>
+
+#define EP93XX_RTC_DATA 0x000
+#define EP93XX_RTC_MATCH 0x004
+#define EP93XX_RTC_STATUS 0x008
+#define EP93XX_RTC_STATUS_INTR BIT(0)
+#define EP93XX_RTC_LOAD 0x00C
+#define EP93XX_RTC_CONTROL 0x010
+#define EP93XX_RTC_CONTROL_MIE BIT(0)
+#define EP93XX_RTC_SWCOMP 0x108
+#define EP93XX_RTC_SWCOMP_DEL_MASK 0x001f0000
+#define EP93XX_RTC_SWCOMP_DEL_SHIFT 16
+#define EP93XX_RTC_SWCOMP_INT_MASK 0x0000ffff
+#define EP93XX_RTC_SWCOMP_INT_SHIFT 0
+
+struct ep93xx_rtc {
+ void __iomem *mmio_base;
+};
+
+static int ep93xx_rtc_get_swcomp(struct device *dev, unsigned short *preload,
+ unsigned short *delete)
+{
+ struct ep93xx_rtc *ep93xx_rtc = dev_get_drvdata(dev);
+ unsigned long comp;
+
+ comp = readl(ep93xx_rtc->mmio_base + EP93XX_RTC_SWCOMP);
+
+ if (preload)
+ *preload = (comp & EP93XX_RTC_SWCOMP_INT_MASK)
+ >> EP93XX_RTC_SWCOMP_INT_SHIFT;
+
+ if (delete)
+ *delete = (comp & EP93XX_RTC_SWCOMP_DEL_MASK)
+ >> EP93XX_RTC_SWCOMP_DEL_SHIFT;
+
+ return 0;
+}
+
+static int ep93xx_rtc_read_time(struct device *dev, struct rtc_time *tm)
+{
+ struct ep93xx_rtc *ep93xx_rtc = dev_get_drvdata(dev);
+ unsigned long time;
+
+ time = readl(ep93xx_rtc->mmio_base + EP93XX_RTC_DATA);
+
+ rtc_time64_to_tm(time, tm);
+ return 0;
+}
+
+static int ep93xx_rtc_set_time(struct device *dev, struct rtc_time *tm)
+{
+ struct ep93xx_rtc *ep93xx_rtc = dev_get_drvdata(dev);
+ unsigned long secs = rtc_tm_to_time64(tm);
+
+ writel(secs + 1, ep93xx_rtc->mmio_base + EP93XX_RTC_LOAD);
+ return 0;
+}
+
+static int ep93xx_rtc_proc(struct device *dev, struct seq_file *seq)
+{
+ unsigned short preload, delete;
+
+ ep93xx_rtc_get_swcomp(dev, &preload, &delete);
+
+ seq_printf(seq, "preload\t\t: %d\n", preload);
+ seq_printf(seq, "delete\t\t: %d\n", delete);
+
+ return 0;
+}
+
+static const struct rtc_class_ops ep93xx_rtc_ops = {
+ .read_time = ep93xx_rtc_read_time,
+ .set_time = ep93xx_rtc_set_time,
+ .proc = ep93xx_rtc_proc,
+};
+
+static ssize_t comp_preload_show(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ unsigned short preload;
+
+ ep93xx_rtc_get_swcomp(dev->parent, &preload, NULL);
+
+ return sprintf(buf, "%d\n", preload);
+}
+static DEVICE_ATTR_RO(comp_preload);
+
+static ssize_t comp_delete_show(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ unsigned short delete;
+
+ ep93xx_rtc_get_swcomp(dev->parent, NULL, &delete);
+
+ return sprintf(buf, "%d\n", delete);
+}
+static DEVICE_ATTR_RO(comp_delete);
+
+static struct attribute *ep93xx_rtc_attrs[] = {
+ &dev_attr_comp_preload.attr,
+ &dev_attr_comp_delete.attr,
+ NULL
+};
+
+static const struct attribute_group ep93xx_rtc_sysfs_files = {
+ .attrs = ep93xx_rtc_attrs,
+};
+
+static int ep93xx_rtc_probe(struct platform_device *pdev)
+{
+ struct ep93xx_rtc *ep93xx_rtc;
+ struct rtc_device *rtc;
+ int err;
+
+ ep93xx_rtc = devm_kzalloc(&pdev->dev, sizeof(*ep93xx_rtc), GFP_KERNEL);
+ if (!ep93xx_rtc)
+ return -ENOMEM;
+
+ ep93xx_rtc->mmio_base = devm_platform_ioremap_resource(pdev, 0);
+ if (IS_ERR(ep93xx_rtc->mmio_base))
+ return PTR_ERR(ep93xx_rtc->mmio_base);
+
+ platform_set_drvdata(pdev, ep93xx_rtc);
+
+ rtc = devm_rtc_allocate_device(&pdev->dev);
+ if (IS_ERR(rtc))
+ return PTR_ERR(rtc);
+
+ rtc->ops = &ep93xx_rtc_ops;
+ rtc->range_max = U32_MAX;
+
+ err = rtc_add_group(rtc, &ep93xx_rtc_sysfs_files);
+ if (err)
+ return err;
+
+ return devm_rtc_register_device(rtc);
+}
+
+static const struct of_device_id ep93xx_rtc_of_ids[] = {
+ { .compatible = "cirrus,ep9301-rtc" },
+ { /* sentinel */ }
+};
+MODULE_DEVICE_TABLE(of, ep93xx_rtc_of_ids);
+
+static struct platform_driver ep93xx_rtc_driver = {
+ .driver = {
+ .name = "ep93xx-rtc",
+ .of_match_table = ep93xx_rtc_of_ids,
+ },
+ .probe = ep93xx_rtc_probe,
+};
+
+module_platform_driver(ep93xx_rtc_driver);
+
+MODULE_AUTHOR("Alessandro Zummo <a.zummo@towertech.it>");
+MODULE_DESCRIPTION("EP93XX RTC driver");
+MODULE_LICENSE("GPL");
+MODULE_ALIAS("platform:ep93xx-rtc");