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

1 files changed, 359 insertions, 0 deletions

diff --git a/drivers/rtc/rtc-sunplus.c b/drivers/rtc/rtc-sunplus.c
new file mode 100644
index 000000000..519a06e72
--- /dev/null
+++ b/drivers/rtc/rtc-sunplus.c
@@ -0,0 +1,359 @@
+// SPDX-License-Identifier: GPL-2.0
+
+/*
+ * The RTC driver for Sunplus	SP7021
+ *
+ * Copyright (C) 2019 Sunplus Technology Inc., All rights reseerved.
+ */
+
+#include <linux/bitfield.h>
+#include <linux/clk.h>
+#include <linux/err.h>
+#include <linux/io.h>
+#include <linux/ktime.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/platform_device.h>
+#include <linux/reset.h>
+#include <linux/rtc.h>
+
+#define RTC_REG_NAME			"rtc"
+
+#define RTC_CTRL			0x40
+#define TIMER_FREEZE_MASK_BIT		BIT(5 + 16)
+#define TIMER_FREEZE			BIT(5)
+#define DIS_SYS_RST_RTC_MASK_BIT	BIT(4 + 16)
+#define DIS_SYS_RST_RTC			BIT(4)
+#define RTC32K_MODE_RESET_MASK_BIT	BIT(3 + 16)
+#define RTC32K_MODE_RESET		BIT(3)
+#define ALARM_EN_OVERDUE_MASK_BIT	BIT(2 + 16)
+#define ALARM_EN_OVERDUE		BIT(2)
+#define ALARM_EN_PMC_MASK_BIT		BIT(1 + 16)
+#define ALARM_EN_PMC			BIT(1)
+#define ALARM_EN_MASK_BIT		BIT(0 + 16)
+#define ALARM_EN			BIT(0)
+#define RTC_TIMER_OUT			0x44
+#define RTC_DIVIDER			0x48
+#define RTC_TIMER_SET			0x4c
+#define RTC_ALARM_SET			0x50
+#define RTC_USER_DATA			0x54
+#define RTC_RESET_RECORD		0x58
+#define RTC_BATT_CHARGE_CTRL		0x5c
+#define BAT_CHARGE_RSEL_MASK_BIT	GENMASK(3 + 16, 2 + 16)
+#define BAT_CHARGE_RSEL_MASK		GENMASK(3, 2)
+#define BAT_CHARGE_RSEL_2K_OHM		FIELD_PREP(BAT_CHARGE_RSEL_MASK, 0)
+#define BAT_CHARGE_RSEL_250_OHM		FIELD_PREP(BAT_CHARGE_RSEL_MASK, 1)
+#define BAT_CHARGE_RSEL_50_OHM		FIELD_PREP(BAT_CHARGE_RSEL_MASK, 2)
+#define BAT_CHARGE_RSEL_0_OHM		FIELD_PREP(BAT_CHARGE_RSEL_MASK, 3)
+#define BAT_CHARGE_DSEL_MASK_BIT	BIT(1 + 16)
+#define BAT_CHARGE_DSEL_MASK		GENMASK(1, 1)
+#define BAT_CHARGE_DSEL_ON		FIELD_PREP(BAT_CHARGE_DSEL_MASK, 0)
+#define BAT_CHARGE_DSEL_OFF		FIELD_PREP(BAT_CHARGE_DSEL_MASK, 1)
+#define BAT_CHARGE_EN_MASK_BIT		BIT(0 + 16)
+#define BAT_CHARGE_EN			BIT(0)
+#define RTC_TRIM_CTRL			0x60
+
+struct sunplus_rtc {
+	struct rtc_device *rtc;
+	struct resource *res;
+	struct clk *rtcclk;
+	struct reset_control *rstc;
+	void __iomem *reg_base;
+	int irq;
+};
+
+static void sp_get_seconds(struct device *dev, unsigned long *secs)
+{
+	struct sunplus_rtc *sp_rtc = dev_get_drvdata(dev);
+
+	*secs = (unsigned long)readl(sp_rtc->reg_base + RTC_TIMER_OUT);
+}
+
+static void sp_set_seconds(struct device *dev, unsigned long secs)
+{
+	struct sunplus_rtc *sp_rtc = dev_get_drvdata(dev);
+
+	writel((u32)secs, sp_rtc->reg_base + RTC_TIMER_SET);
+}
+
+static int sp_rtc_read_time(struct device *dev, struct rtc_time *tm)
+{
+	unsigned long secs;
+
+	sp_get_seconds(dev, &secs);
+	rtc_time64_to_tm(secs, tm);
+
+	return 0;
+}
+
+static int sp_rtc_set_time(struct device *dev, struct rtc_time *tm)
+{
+	unsigned long secs;
+
+	secs = rtc_tm_to_time64(tm);
+	dev_dbg(dev, "%s, secs = %lu\n", __func__, secs);
+	sp_set_seconds(dev, secs);
+
+	return 0;
+}
+
+static int sp_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alrm)
+{
+	struct sunplus_rtc *sp_rtc = dev_get_drvdata(dev);
+	unsigned long alarm_time;
+
+	alarm_time = rtc_tm_to_time64(&alrm->time);
+	dev_dbg(dev, "%s, alarm_time: %u\n", __func__, (u32)(alarm_time));
+	writel((u32)alarm_time, sp_rtc->reg_base + RTC_ALARM_SET);
+
+	return 0;
+}
+
+static int sp_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *alrm)
+{
+	struct sunplus_rtc *sp_rtc = dev_get_drvdata(dev);
+	unsigned int alarm_time;
+
+	alarm_time = readl(sp_rtc->reg_base + RTC_ALARM_SET);
+	dev_dbg(dev, "%s, alarm_time: %u\n", __func__, alarm_time);
+
+	if (alarm_time == 0)
+		alrm->enabled = 0;
+	else
+		alrm->enabled = 1;
+
+	rtc_time64_to_tm((unsigned long)(alarm_time), &alrm->time);
+
+	return 0;
+}
+
+static int sp_rtc_alarm_irq_enable(struct device *dev, unsigned int enabled)
+{
+	struct sunplus_rtc *sp_rtc = dev_get_drvdata(dev);
+
+	if (enabled)
+		writel((TIMER_FREEZE_MASK_BIT | DIS_SYS_RST_RTC_MASK_BIT |
+			RTC32K_MODE_RESET_MASK_BIT | ALARM_EN_OVERDUE_MASK_BIT |
+			ALARM_EN_PMC_MASK_BIT | ALARM_EN_MASK_BIT) |
+			(DIS_SYS_RST_RTC | ALARM_EN_OVERDUE | ALARM_EN_PMC | ALARM_EN),
+			sp_rtc->reg_base + RTC_CTRL);
+	else
+		writel((ALARM_EN_OVERDUE_MASK_BIT | ALARM_EN_PMC_MASK_BIT | ALARM_EN_MASK_BIT) |
+			0x0, sp_rtc->reg_base + RTC_CTRL);
+
+	return 0;
+}
+
+static const struct rtc_class_ops sp_rtc_ops = {
+	.read_time =		sp_rtc_read_time,
+	.set_time =		sp_rtc_set_time,
+	.set_alarm =		sp_rtc_set_alarm,
+	.read_alarm =		sp_rtc_read_alarm,
+	.alarm_irq_enable =	sp_rtc_alarm_irq_enable,
+};
+
+static irqreturn_t sp_rtc_irq_handler(int irq, void *dev_id)
+{
+	struct platform_device *plat_dev = dev_id;
+	struct sunplus_rtc *sp_rtc = dev_get_drvdata(&plat_dev->dev);
+
+	rtc_update_irq(sp_rtc->rtc, 1, RTC_IRQF | RTC_AF);
+	dev_dbg(&plat_dev->dev, "[RTC] ALARM INT\n");
+
+	return IRQ_HANDLED;
+}
+
+/*
+ * -------------------------------------------------------------------------------------
+ * bat_charge_rsel   bat_charge_dsel   bat_charge_en     Remarks
+ *         x              x                 0            Disable
+ *         0              0                 1            0.86mA (2K Ohm with diode)
+ *         1              0                 1            1.81mA (250 Ohm with diode)
+ *         2              0                 1            2.07mA (50 Ohm with diode)
+ *         3              0                 1            16.0mA (0 Ohm with diode)
+ *         0              1                 1            1.36mA (2K Ohm without diode)
+ *         1              1                 1            3.99mA (250 Ohm without diode)
+ *         2              1                 1            4.41mA (50 Ohm without diode)
+ *         3              1                 1            16.0mA (0 Ohm without diode)
+ * -------------------------------------------------------------------------------------
+ */
+static void sp_rtc_set_trickle_charger(struct device dev)
+{
+	struct sunplus_rtc *sp_rtc = dev_get_drvdata(&dev);
+	u32 ohms, rsel;
+	u32 chargeable;
+
+	if (of_property_read_u32(dev.of_node, "trickle-resistor-ohms", &ohms) ||
+	    of_property_read_u32(dev.of_node, "aux-voltage-chargeable", &chargeable)) {
+		dev_warn(&dev, "battery charger disabled\n");
+		return;
+	}
+
+	switch (ohms) {
+	case 2000:
+		rsel = BAT_CHARGE_RSEL_2K_OHM;
+		break;
+	case 250:
+		rsel = BAT_CHARGE_RSEL_250_OHM;
+		break;
+	case 50:
+		rsel = BAT_CHARGE_RSEL_50_OHM;
+		break;
+	case 0:
+		rsel = BAT_CHARGE_RSEL_0_OHM;
+		break;
+	default:
+		dev_err(&dev, "invalid charger resistor value (%d)\n", ohms);
+		return;
+	}
+
+	writel(BAT_CHARGE_RSEL_MASK_BIT | rsel, sp_rtc->reg_base + RTC_BATT_CHARGE_CTRL);
+
+	switch (chargeable) {
+	case 0:
+		writel(BAT_CHARGE_DSEL_MASK_BIT | BAT_CHARGE_DSEL_OFF,
+		       sp_rtc->reg_base + RTC_BATT_CHARGE_CTRL);
+		break;
+	case 1:
+		writel(BAT_CHARGE_DSEL_MASK_BIT | BAT_CHARGE_DSEL_ON,
+		       sp_rtc->reg_base + RTC_BATT_CHARGE_CTRL);
+		break;
+	default:
+		dev_err(&dev, "invalid aux-voltage-chargeable value (%d)\n", chargeable);
+		return;
+	}
+
+	writel(BAT_CHARGE_EN_MASK_BIT | BAT_CHARGE_EN, sp_rtc->reg_base + RTC_BATT_CHARGE_CTRL);
+}
+
+static int sp_rtc_probe(struct platform_device *plat_dev)
+{
+	struct sunplus_rtc *sp_rtc;
+	int ret;
+
+	sp_rtc = devm_kzalloc(&plat_dev->dev, sizeof(*sp_rtc), GFP_KERNEL);
+	if (!sp_rtc)
+		return -ENOMEM;
+
+	sp_rtc->reg_base = devm_platform_ioremap_resource_byname(plat_dev, RTC_REG_NAME);
+	if (IS_ERR(sp_rtc->reg_base))
+		return dev_err_probe(&plat_dev->dev, PTR_ERR(sp_rtc->reg_base),
+					    "%s devm_ioremap_resource fail\n", RTC_REG_NAME);
+	dev_dbg(&plat_dev->dev, "res = %pR, reg_base = %p\n",
+		sp_rtc->res, sp_rtc->reg_base);
+
+	sp_rtc->irq = platform_get_irq(plat_dev, 0);
+	if (sp_rtc->irq < 0)
+		return sp_rtc->irq;
+
+	ret = devm_request_irq(&plat_dev->dev, sp_rtc->irq, sp_rtc_irq_handler,
+			       IRQF_TRIGGER_RISING, "rtc irq", plat_dev);
+	if (ret)
+		return dev_err_probe(&plat_dev->dev, ret, "devm_request_irq failed:\n");
+
+	sp_rtc->rtcclk = devm_clk_get(&plat_dev->dev, NULL);
+	if (IS_ERR(sp_rtc->rtcclk))
+		return dev_err_probe(&plat_dev->dev, PTR_ERR(sp_rtc->rtcclk),
+					    "devm_clk_get fail\n");
+
+	sp_rtc->rstc = devm_reset_control_get_exclusive(&plat_dev->dev, NULL);
+	if (IS_ERR(sp_rtc->rstc))
+		return dev_err_probe(&plat_dev->dev, PTR_ERR(sp_rtc->rstc),
+					    "failed to retrieve reset controller\n");
+
+	ret = clk_prepare_enable(sp_rtc->rtcclk);
+	if (ret)
+		goto free_clk;
+
+	ret = reset_control_deassert(sp_rtc->rstc);
+	if (ret)
+		goto free_reset_assert;
+
+	device_init_wakeup(&plat_dev->dev, true);
+	dev_set_drvdata(&plat_dev->dev, sp_rtc);
+
+	sp_rtc->rtc = devm_rtc_allocate_device(&plat_dev->dev);
+	if (IS_ERR(sp_rtc->rtc)) {
+		ret = PTR_ERR(sp_rtc->rtc);
+		goto free_reset_assert;
+	}
+
+	sp_rtc->rtc->range_max = U32_MAX;
+	sp_rtc->rtc->range_min = 0;
+	sp_rtc->rtc->ops = &sp_rtc_ops;
+
+	ret = devm_rtc_register_device(sp_rtc->rtc);
+	if (ret)
+		goto free_reset_assert;
+
+	/* Setup trickle charger */
+	if (plat_dev->dev.of_node)
+		sp_rtc_set_trickle_charger(plat_dev->dev);
+
+	/* Keep RTC from system reset */
+	writel(DIS_SYS_RST_RTC_MASK_BIT | DIS_SYS_RST_RTC, sp_rtc->reg_base + RTC_CTRL);
+
+	return 0;
+
+free_reset_assert:
+	reset_control_assert(sp_rtc->rstc);
+free_clk:
+	clk_disable_unprepare(sp_rtc->rtcclk);
+
+	return ret;
+}
+
+static void sp_rtc_remove(struct platform_device *plat_dev)
+{
+	struct sunplus_rtc *sp_rtc = dev_get_drvdata(&plat_dev->dev);
+
+	device_init_wakeup(&plat_dev->dev, false);
+	reset_control_assert(sp_rtc->rstc);
+	clk_disable_unprepare(sp_rtc->rtcclk);
+}
+
+#ifdef CONFIG_PM_SLEEP
+static int sp_rtc_suspend(struct device *dev)
+{
+	struct sunplus_rtc *sp_rtc = dev_get_drvdata(dev);
+
+	if (device_may_wakeup(dev))
+		enable_irq_wake(sp_rtc->irq);
+
+	return 0;
+}
+
+static int sp_rtc_resume(struct device *dev)
+{
+	struct sunplus_rtc *sp_rtc = dev_get_drvdata(dev);
+
+	if (device_may_wakeup(dev))
+		disable_irq_wake(sp_rtc->irq);
+
+	return 0;
+}
+#endif
+
+static const struct of_device_id sp_rtc_of_match[] = {
+	{ .compatible = "sunplus,sp7021-rtc" },
+	{ /* sentinel */ }
+};
+MODULE_DEVICE_TABLE(of, sp_rtc_of_match);
+
+static SIMPLE_DEV_PM_OPS(sp_rtc_pm_ops, sp_rtc_suspend, sp_rtc_resume);
+
+static struct platform_driver sp_rtc_driver = {
+	.probe   = sp_rtc_probe,
+	.remove = sp_rtc_remove,
+	.driver  = {
+		.name	= "sp7021-rtc",
+		.of_match_table = sp_rtc_of_match,
+		.pm	= &sp_rtc_pm_ops,
+	},
+};
+module_platform_driver(sp_rtc_driver);
+
+MODULE_AUTHOR("Vincent Shih <vincent.sunplus@gmail.com>");
+MODULE_DESCRIPTION("Sunplus RTC driver");
+MODULE_LICENSE("GPL v2");
+