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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-amlogic-a4.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-amlogic-a4.c')
-rw-r--r--drivers/rtc/rtc-amlogic-a4.c443
1 files changed, 443 insertions, 0 deletions
diff --git a/drivers/rtc/rtc-amlogic-a4.c b/drivers/rtc/rtc-amlogic-a4.c
new file mode 100644
index 000000000..50938c35a
--- /dev/null
+++ b/drivers/rtc/rtc-amlogic-a4.c
@@ -0,0 +1,443 @@
+// SPDX-License-Identifier: (GPL-2.0-only OR MIT)
+/*
+ * Copyright (C) 2024 Amlogic, Inc. All rights reserved
+ * Author: Yiting Deng <yiting.deng@amlogic.com>
+ */
+
+#include <linux/bitfield.h>
+#include <linux/clk.h>
+#include <linux/clk-provider.h>
+#include <linux/delay.h>
+#include <linux/module.h>
+#include <linux/platform_device.h>
+#include <linux/regmap.h>
+#include <linux/rtc.h>
+#include <linux/time64.h>
+
+/* rtc oscillator rate */
+#define OSC_32K 32768
+#define OSC_24M 24000000
+
+#define RTC_CTRL (0x0 << 2) /* Control RTC */
+#define RTC_ALRM0_EN BIT(0)
+#define RTC_OSC_SEL BIT(8)
+#define RTC_ENABLE BIT(12)
+
+#define RTC_COUNTER_REG (0x1 << 2) /* Program RTC counter initial value */
+
+#define RTC_ALARM0_REG (0x2 << 2) /* Program RTC alarm0 value */
+
+#define RTC_SEC_ADJUST_REG (0x6 << 2) /* Control second-based timing adjustment */
+#define RTC_MATCH_COUNTER GENMASK(18, 0)
+#define RTC_SEC_ADJUST_CTRL GENMASK(20, 19)
+#define RTC_ADJ_VALID BIT(23)
+
+#define RTC_INT_MASK (0x8 << 2) /* RTC interrupt mask */
+#define RTC_ALRM0_IRQ_MSK BIT(0)
+
+#define RTC_INT_CLR (0x9 << 2) /* Clear RTC interrupt */
+#define RTC_ALRM0_IRQ_CLR BIT(0)
+
+#define RTC_OSCIN_CTRL0 (0xa << 2) /* Control RTC clk from 24M */
+#define RTC_OSCIN_CTRL1 (0xb << 2) /* Control RTC clk from 24M */
+#define RTC_OSCIN_IN_EN BIT(31)
+#define RTC_OSCIN_OUT_CFG GENMASK(29, 28)
+#define RTC_OSCIN_OUT_N0M0 GENMASK(11, 0)
+#define RTC_OSCIN_OUT_N1M1 GENMASK(23, 12)
+
+#define RTC_INT_STATUS (0xc << 2) /* RTC interrupt status */
+#define RTC_ALRM0_IRQ_STATUS BIT(0)
+
+#define RTC_REAL_TIME (0xd << 2) /* RTC time value */
+
+#define RTC_OSCIN_OUT_32K_N0 0x2dc
+#define RTC_OSCIN_OUT_32K_N1 0x2db
+#define RTC_OSCIN_OUT_32K_M0 0x1
+#define RTC_OSCIN_OUT_32K_M1 0x2
+
+#define RTC_SWALLOW_SECOND 0x2
+#define RTC_INSERT_SECOND 0x3
+
+struct aml_rtc_config {
+ bool gray_stored;
+};
+
+struct aml_rtc_data {
+ struct regmap *map;
+ struct rtc_device *rtc_dev;
+ int irq;
+ struct clk *rtc_clk;
+ struct clk *sys_clk;
+ int rtc_enabled;
+ const struct aml_rtc_config *config;
+};
+
+static inline u32 gray_to_binary(u32 gray)
+{
+ u32 bcd = gray;
+ int size = sizeof(bcd) * 8;
+ int i;
+
+ for (i = 0; (1 << i) < size; i++)
+ bcd ^= bcd >> (1 << i);
+
+ return bcd;
+}
+
+static inline u32 binary_to_gray(u32 bcd)
+{
+ return bcd ^ (bcd >> 1);
+}
+
+static int aml_rtc_read_time(struct device *dev, struct rtc_time *tm)
+{
+ struct aml_rtc_data *rtc = dev_get_drvdata(dev);
+ u32 time_sec;
+
+ /* if RTC disabled, read time failed */
+ if (!rtc->rtc_enabled)
+ return -EINVAL;
+
+ regmap_read(rtc->map, RTC_REAL_TIME, &time_sec);
+ if (rtc->config->gray_stored)
+ time_sec = gray_to_binary(time_sec);
+ rtc_time64_to_tm(time_sec, tm);
+ dev_dbg(dev, "%s: read time = %us\n", __func__, time_sec);
+
+ return 0;
+}
+
+static int aml_rtc_set_time(struct device *dev, struct rtc_time *tm)
+{
+ struct aml_rtc_data *rtc = dev_get_drvdata(dev);
+ u32 time_sec;
+
+ /* if RTC disabled, first enable it */
+ if (!rtc->rtc_enabled) {
+ regmap_write_bits(rtc->map, RTC_CTRL, RTC_ENABLE, RTC_ENABLE);
+ usleep_range(100, 200);
+ rtc->rtc_enabled = regmap_test_bits(rtc->map, RTC_CTRL, RTC_ENABLE);
+ if (!rtc->rtc_enabled)
+ return -EINVAL;
+ }
+
+ time_sec = rtc_tm_to_time64(tm);
+ if (rtc->config->gray_stored)
+ time_sec = binary_to_gray(time_sec);
+ regmap_write(rtc->map, RTC_COUNTER_REG, time_sec);
+ dev_dbg(dev, "%s: set time = %us\n", __func__, time_sec);
+
+ return 0;
+}
+
+static int aml_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alarm)
+{
+ struct aml_rtc_data *rtc = dev_get_drvdata(dev);
+ time64_t alarm_sec;
+
+ /* if RTC disabled, set alarm failed */
+ if (!rtc->rtc_enabled)
+ return -EINVAL;
+
+ regmap_update_bits(rtc->map, RTC_CTRL,
+ RTC_ALRM0_EN, RTC_ALRM0_EN);
+ regmap_update_bits(rtc->map, RTC_INT_MASK,
+ RTC_ALRM0_IRQ_MSK, 0);
+
+ alarm_sec = rtc_tm_to_time64(&alarm->time);
+ if (rtc->config->gray_stored)
+ alarm_sec = binary_to_gray(alarm_sec);
+ regmap_write(rtc->map, RTC_ALARM0_REG, alarm_sec);
+
+ dev_dbg(dev, "%s: alarm->enabled=%d alarm_set=%llds\n", __func__,
+ alarm->enabled, alarm_sec);
+
+ return 0;
+}
+
+static int aml_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *alarm)
+{
+ struct aml_rtc_data *rtc = dev_get_drvdata(dev);
+ u32 alarm_sec;
+ int alarm_enable;
+ int alarm_mask;
+
+ /* if RTC disabled, read alarm failed */
+ if (!rtc->rtc_enabled)
+ return -EINVAL;
+
+ regmap_read(rtc->map, RTC_ALARM0_REG, &alarm_sec);
+ if (rtc->config->gray_stored)
+ alarm_sec = gray_to_binary(alarm_sec);
+ rtc_time64_to_tm(alarm_sec, &alarm->time);
+
+ alarm_enable = regmap_test_bits(rtc->map, RTC_CTRL, RTC_ALRM0_EN);
+ alarm_mask = regmap_test_bits(rtc->map, RTC_INT_MASK, RTC_ALRM0_IRQ_MSK);
+ alarm->enabled = (alarm_enable && !alarm_mask) ? 1 : 0;
+ dev_dbg(dev, "%s: alarm->enabled=%d alarm=%us\n", __func__,
+ alarm->enabled, alarm_sec);
+
+ return 0;
+}
+
+static int aml_rtc_read_offset(struct device *dev, long *offset)
+{
+ struct aml_rtc_data *rtc = dev_get_drvdata(dev);
+ u32 reg_val;
+ long val;
+ int sign, match_counter, enable;
+
+ /* if RTC disabled, read offset failed */
+ if (!rtc->rtc_enabled)
+ return -EINVAL;
+
+ regmap_read(rtc->map, RTC_SEC_ADJUST_REG, &reg_val);
+ enable = FIELD_GET(RTC_ADJ_VALID, reg_val);
+ if (!enable) {
+ val = 0;
+ } else {
+ sign = FIELD_GET(RTC_SEC_ADJUST_CTRL, reg_val);
+ match_counter = FIELD_GET(RTC_MATCH_COUNTER, reg_val);
+ val = 1000000000 / (match_counter + 1);
+ if (sign == RTC_SWALLOW_SECOND)
+ val = -val;
+ }
+ *offset = val;
+
+ return 0;
+}
+
+static int aml_rtc_set_offset(struct device *dev, long offset)
+{
+ struct aml_rtc_data *rtc = dev_get_drvdata(dev);
+ int sign = 0;
+ int match_counter = 0;
+ int enable = 0;
+ u32 reg_val;
+
+ /* if RTC disabled, set offset failed */
+ if (!rtc->rtc_enabled)
+ return -EINVAL;
+
+ if (offset) {
+ enable = 1;
+ sign = offset < 0 ? RTC_SWALLOW_SECOND : RTC_INSERT_SECOND;
+ match_counter = 1000000000 / abs(offset) - 1;
+ if (match_counter < 0 || match_counter > RTC_MATCH_COUNTER)
+ return -EINVAL;
+ }
+
+ reg_val = FIELD_PREP(RTC_ADJ_VALID, enable) |
+ FIELD_PREP(RTC_SEC_ADJUST_CTRL, sign) |
+ FIELD_PREP(RTC_MATCH_COUNTER, match_counter);
+ regmap_write(rtc->map, RTC_SEC_ADJUST_REG, reg_val);
+
+ return 0;
+}
+
+static int aml_rtc_alarm_enable(struct device *dev, unsigned int enabled)
+{
+ struct aml_rtc_data *rtc = dev_get_drvdata(dev);
+
+ if (enabled) {
+ regmap_update_bits(rtc->map, RTC_CTRL,
+ RTC_ALRM0_EN, RTC_ALRM0_EN);
+ regmap_update_bits(rtc->map, RTC_INT_MASK,
+ RTC_ALRM0_IRQ_MSK, 0);
+ } else {
+ regmap_update_bits(rtc->map, RTC_INT_MASK,
+ RTC_ALRM0_IRQ_MSK, RTC_ALRM0_IRQ_MSK);
+ regmap_update_bits(rtc->map, RTC_CTRL,
+ RTC_ALRM0_EN, 0);
+ }
+
+ return 0;
+}
+
+static const struct rtc_class_ops aml_rtc_ops = {
+ .read_time = aml_rtc_read_time,
+ .set_time = aml_rtc_set_time,
+ .read_alarm = aml_rtc_read_alarm,
+ .set_alarm = aml_rtc_set_alarm,
+ .alarm_irq_enable = aml_rtc_alarm_enable,
+ .read_offset = aml_rtc_read_offset,
+ .set_offset = aml_rtc_set_offset,
+};
+
+static irqreturn_t aml_rtc_handler(int irq, void *data)
+{
+ struct aml_rtc_data *rtc = (struct aml_rtc_data *)data;
+
+ regmap_write(rtc->map, RTC_ALARM0_REG, 0);
+ regmap_write(rtc->map, RTC_INT_CLR, RTC_ALRM0_IRQ_STATUS);
+
+ rtc_update_irq(rtc->rtc_dev, 1, RTC_AF | RTC_IRQF);
+
+ return IRQ_HANDLED;
+}
+
+static void aml_rtc_init(struct aml_rtc_data *rtc)
+{
+ u32 reg_val = 0;
+
+ rtc->rtc_enabled = regmap_test_bits(rtc->map, RTC_CTRL, RTC_ENABLE);
+ if (!rtc->rtc_enabled) {
+ if (clk_get_rate(rtc->rtc_clk) == OSC_24M) {
+ /* select 24M oscillator */
+ regmap_write_bits(rtc->map, RTC_CTRL, RTC_OSC_SEL, RTC_OSC_SEL);
+
+ /*
+ * Set RTC oscillator to freq_out to freq_in/((N0*M0+N1*M1)/(M0+M1))
+ * Enable clock_in gate of oscillator 24MHz
+ * Set N0 to 733, N1 to 732
+ */
+ reg_val = FIELD_PREP(RTC_OSCIN_IN_EN, 1)
+ | FIELD_PREP(RTC_OSCIN_OUT_CFG, 1)
+ | FIELD_PREP(RTC_OSCIN_OUT_N0M0, RTC_OSCIN_OUT_32K_N0)
+ | FIELD_PREP(RTC_OSCIN_OUT_N1M1, RTC_OSCIN_OUT_32K_N1);
+ regmap_write_bits(rtc->map, RTC_OSCIN_CTRL0, RTC_OSCIN_IN_EN
+ | RTC_OSCIN_OUT_CFG | RTC_OSCIN_OUT_N0M0
+ | RTC_OSCIN_OUT_N1M1, reg_val);
+
+ /* Set M0 to 2, M1 to 3, so freq_out = 32768 Hz*/
+ reg_val = FIELD_PREP(RTC_OSCIN_OUT_N0M0, RTC_OSCIN_OUT_32K_M0)
+ | FIELD_PREP(RTC_OSCIN_OUT_N1M1, RTC_OSCIN_OUT_32K_M1);
+ regmap_write_bits(rtc->map, RTC_OSCIN_CTRL1, RTC_OSCIN_OUT_N0M0
+ | RTC_OSCIN_OUT_N1M1, reg_val);
+ } else {
+ /* select 32K oscillator */
+ regmap_write_bits(rtc->map, RTC_CTRL, RTC_OSC_SEL, 0);
+ }
+ }
+ regmap_write_bits(rtc->map, RTC_INT_MASK,
+ RTC_ALRM0_IRQ_MSK, RTC_ALRM0_IRQ_MSK);
+ regmap_write_bits(rtc->map, RTC_CTRL, RTC_ALRM0_EN, 0);
+}
+
+static int aml_rtc_probe(struct platform_device *pdev)
+{
+ struct device *dev = &pdev->dev;
+ struct aml_rtc_data *rtc;
+ void __iomem *base;
+ int ret = 0;
+
+ const struct regmap_config aml_rtc_regmap_config = {
+ .reg_bits = 32,
+ .val_bits = 32,
+ .reg_stride = 4,
+ .max_register = RTC_REAL_TIME,
+ };
+
+ rtc = devm_kzalloc(dev, sizeof(*rtc), GFP_KERNEL);
+ if (!rtc)
+ return -ENOMEM;
+
+ rtc->config = of_device_get_match_data(dev);
+ if (!rtc->config)
+ return -ENODEV;
+
+ base = devm_platform_ioremap_resource(pdev, 0);
+ if (IS_ERR(base))
+ return dev_err_probe(dev, PTR_ERR(base), "resource ioremap failed\n");
+
+ rtc->map = devm_regmap_init_mmio(dev, base, &aml_rtc_regmap_config);
+ if (IS_ERR(rtc->map))
+ return dev_err_probe(dev, PTR_ERR(rtc->map), "regmap init failed\n");
+
+ rtc->irq = platform_get_irq(pdev, 0);
+ if (rtc->irq < 0)
+ return rtc->irq;
+
+ rtc->rtc_clk = devm_clk_get(dev, "osc");
+ if (IS_ERR(rtc->rtc_clk))
+ return dev_err_probe(dev, PTR_ERR(rtc->rtc_clk),
+ "failed to find rtc clock\n");
+ if (clk_get_rate(rtc->rtc_clk) != OSC_32K && clk_get_rate(rtc->rtc_clk) != OSC_24M)
+ return dev_err_probe(dev, -EINVAL, "Invalid clock configuration\n");
+
+ rtc->sys_clk = devm_clk_get_enabled(dev, "sys");
+ if (IS_ERR(rtc->sys_clk))
+ return dev_err_probe(dev, PTR_ERR(rtc->sys_clk),
+ "failed to get_enable rtc sys clk\n");
+ aml_rtc_init(rtc);
+
+ devm_device_init_wakeup(dev);
+ platform_set_drvdata(pdev, rtc);
+
+ rtc->rtc_dev = devm_rtc_allocate_device(dev);
+ if (IS_ERR(rtc->rtc_dev))
+ return PTR_ERR(rtc->rtc_dev);
+
+ ret = devm_request_irq(dev, rtc->irq, aml_rtc_handler,
+ 0, "aml-rtc alarm", rtc);
+ if (ret) {
+ dev_err_probe(dev, ret, "IRQ%d request failed, ret = %d\n",
+ rtc->irq, ret);
+ return ret;
+ }
+
+ rtc->rtc_dev->ops = &aml_rtc_ops;
+ rtc->rtc_dev->range_min = 0;
+ rtc->rtc_dev->range_max = U32_MAX;
+
+ return devm_rtc_register_device(rtc->rtc_dev);
+}
+
+#ifdef CONFIG_PM_SLEEP
+static int aml_rtc_suspend(struct device *dev)
+{
+ struct aml_rtc_data *rtc = dev_get_drvdata(dev);
+
+ if (device_may_wakeup(dev))
+ enable_irq_wake(rtc->irq);
+
+ return 0;
+}
+
+static int aml_rtc_resume(struct device *dev)
+{
+ struct aml_rtc_data *rtc = dev_get_drvdata(dev);
+
+ if (device_may_wakeup(dev))
+ disable_irq_wake(rtc->irq);
+
+ return 0;
+}
+#endif
+
+static SIMPLE_DEV_PM_OPS(aml_rtc_pm_ops,
+ aml_rtc_suspend, aml_rtc_resume);
+
+static const struct aml_rtc_config a5_rtc_config = {
+};
+
+static const struct aml_rtc_config a4_rtc_config = {
+ .gray_stored = true,
+};
+
+static const struct of_device_id aml_rtc_device_id[] = {
+ {
+ .compatible = "amlogic,a4-rtc",
+ .data = &a4_rtc_config,
+ },
+ {
+ .compatible = "amlogic,a5-rtc",
+ .data = &a5_rtc_config,
+ },
+ { }
+};
+MODULE_DEVICE_TABLE(of, aml_rtc_device_id);
+
+static struct platform_driver aml_rtc_driver = {
+ .probe = aml_rtc_probe,
+ .driver = {
+ .name = "aml-rtc",
+ .pm = &aml_rtc_pm_ops,
+ .of_match_table = aml_rtc_device_id,
+ },
+};
+
+module_platform_driver(aml_rtc_driver);
+MODULE_DESCRIPTION("Amlogic RTC driver");
+MODULE_AUTHOR("Yiting Deng <yiting.deng@amlogic.com>");
+MODULE_LICENSE("GPL");