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, 477 insertions, 0 deletions

diff --git a/drivers/rtc/rtc-ds1343.c b/drivers/rtc/rtc-ds1343.c
new file mode 100644
index 000000000..54f6af788
--- /dev/null
+++ b/drivers/rtc/rtc-ds1343.c
@@ -0,0 +1,477 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/* rtc-ds1343.c
+ *
+ * Driver for Dallas Semiconductor DS1343 Low Current, SPI Compatible
+ * Real Time Clock
+ *
+ * Author : Raghavendra Chandra Ganiga <ravi23ganiga@gmail.com>
+ *	    Ankur Srivastava <sankurece@gmail.com> : DS1343 Nvram Support
+ */
+
+#include <linux/init.h>
+#include <linux/module.h>
+#include <linux/interrupt.h>
+#include <linux/device.h>
+#include <linux/spi/spi.h>
+#include <linux/regmap.h>
+#include <linux/rtc.h>
+#include <linux/bcd.h>
+#include <linux/pm.h>
+#include <linux/pm_wakeirq.h>
+#include <linux/slab.h>
+
+#define DALLAS_MAXIM_DS1343	0
+#define DALLAS_MAXIM_DS1344	1
+
+/* RTC DS1343 Registers */
+#define DS1343_SECONDS_REG	0x00
+#define DS1343_MINUTES_REG	0x01
+#define DS1343_HOURS_REG	0x02
+#define DS1343_DAY_REG		0x03
+#define DS1343_DATE_REG		0x04
+#define DS1343_MONTH_REG	0x05
+#define DS1343_YEAR_REG		0x06
+#define DS1343_ALM0_SEC_REG	0x07
+#define DS1343_ALM0_MIN_REG	0x08
+#define DS1343_ALM0_HOUR_REG	0x09
+#define DS1343_ALM0_DAY_REG	0x0A
+#define DS1343_ALM1_SEC_REG	0x0B
+#define DS1343_ALM1_MIN_REG	0x0C
+#define DS1343_ALM1_HOUR_REG	0x0D
+#define DS1343_ALM1_DAY_REG	0x0E
+#define DS1343_CONTROL_REG	0x0F
+#define DS1343_STATUS_REG	0x10
+#define DS1343_TRICKLE_REG	0x11
+#define DS1343_NVRAM		0x20
+
+#define DS1343_NVRAM_LEN	96
+
+/* DS1343 Control Registers bits */
+#define DS1343_EOSC		0x80
+#define DS1343_DOSF		0x20
+#define DS1343_EGFIL		0x10
+#define DS1343_SQW		0x08
+#define DS1343_INTCN		0x04
+#define DS1343_A1IE		0x02
+#define DS1343_A0IE		0x01
+
+/* DS1343 Status Registers bits */
+#define DS1343_OSF		0x80
+#define DS1343_IRQF1		0x02
+#define DS1343_IRQF0		0x01
+
+/* DS1343 Trickle Charger Registers bits */
+#define DS1343_TRICKLE_MAGIC	0xa0
+#define DS1343_TRICKLE_DS1	0x08
+#define DS1343_TRICKLE_1K	0x01
+#define DS1343_TRICKLE_2K	0x02
+#define DS1343_TRICKLE_4K	0x03
+
+static const struct spi_device_id ds1343_id[] = {
+	{ "ds1343", DALLAS_MAXIM_DS1343 },
+	{ "ds1344", DALLAS_MAXIM_DS1344 },
+	{ }
+};
+MODULE_DEVICE_TABLE(spi, ds1343_id);
+
+struct ds1343_priv {
+	struct rtc_device *rtc;
+	struct regmap *map;
+	int irq;
+};
+
+static ssize_t ds1343_show_glitchfilter(struct device *dev,
+				struct device_attribute *attr, char *buf)
+{
+	struct ds1343_priv *priv = dev_get_drvdata(dev->parent);
+	int glitch_filt_status, data;
+	int res;
+
+	res = regmap_read(priv->map, DS1343_CONTROL_REG, &data);
+	if (res)
+		return res;
+
+	glitch_filt_status = !!(data & DS1343_EGFIL);
+
+	if (glitch_filt_status)
+		return sprintf(buf, "enabled\n");
+	else
+		return sprintf(buf, "disabled\n");
+}
+
+static ssize_t ds1343_store_glitchfilter(struct device *dev,
+					struct device_attribute *attr,
+					const char *buf, size_t count)
+{
+	struct ds1343_priv *priv = dev_get_drvdata(dev->parent);
+	int data = 0;
+	int res;
+
+	if (strncmp(buf, "enabled", 7) == 0)
+		data = DS1343_EGFIL;
+	else if (strncmp(buf, "disabled", 8))
+		return -EINVAL;
+
+	res = regmap_update_bits(priv->map, DS1343_CONTROL_REG,
+				 DS1343_EGFIL, data);
+	if (res)
+		return res;
+
+	return count;
+}
+
+static DEVICE_ATTR(glitch_filter, 0644, ds1343_show_glitchfilter,
+			ds1343_store_glitchfilter);
+
+static int ds1343_nvram_write(void *priv, unsigned int off, void *val,
+			      size_t bytes)
+{
+	struct ds1343_priv *ds1343 = priv;
+
+	return regmap_bulk_write(ds1343->map, DS1343_NVRAM + off, val, bytes);
+}
+
+static int ds1343_nvram_read(void *priv, unsigned int off, void *val,
+			     size_t bytes)
+{
+	struct ds1343_priv *ds1343 = priv;
+
+	return regmap_bulk_read(ds1343->map, DS1343_NVRAM + off, val, bytes);
+}
+
+static ssize_t ds1343_show_tricklecharger(struct device *dev,
+				struct device_attribute *attr, char *buf)
+{
+	struct ds1343_priv *priv = dev_get_drvdata(dev->parent);
+	int res, data;
+	char *diodes = "disabled", *resistors = " ";
+
+	res = regmap_read(priv->map, DS1343_TRICKLE_REG, &data);
+	if (res)
+		return res;
+
+	if ((data & 0xf0) == DS1343_TRICKLE_MAGIC) {
+		switch (data & 0x0c) {
+		case DS1343_TRICKLE_DS1:
+			diodes = "one diode,";
+			break;
+
+		default:
+			diodes = "no diode,";
+			break;
+		}
+
+		switch (data & 0x03) {
+		case DS1343_TRICKLE_1K:
+			resistors = "1k Ohm";
+			break;
+
+		case DS1343_TRICKLE_2K:
+			resistors = "2k Ohm";
+			break;
+
+		case DS1343_TRICKLE_4K:
+			resistors = "4k Ohm";
+			break;
+
+		default:
+			diodes = "disabled";
+			break;
+		}
+	}
+
+	return sprintf(buf, "%s %s\n", diodes, resistors);
+}
+
+static DEVICE_ATTR(trickle_charger, 0444, ds1343_show_tricklecharger, NULL);
+
+static struct attribute *ds1343_attrs[] = {
+	&dev_attr_glitch_filter.attr,
+	&dev_attr_trickle_charger.attr,
+	NULL
+};
+
+static const struct attribute_group ds1343_attr_group = {
+	.attrs  = ds1343_attrs,
+};
+
+static int ds1343_read_time(struct device *dev, struct rtc_time *dt)
+{
+	struct ds1343_priv *priv = dev_get_drvdata(dev);
+	unsigned char buf[7];
+	int res;
+
+	res = regmap_bulk_read(priv->map, DS1343_SECONDS_REG, buf, 7);
+	if (res)
+		return res;
+
+	dt->tm_sec	= bcd2bin(buf[0]);
+	dt->tm_min	= bcd2bin(buf[1]);
+	dt->tm_hour	= bcd2bin(buf[2] & 0x3F);
+	dt->tm_wday	= bcd2bin(buf[3]) - 1;
+	dt->tm_mday	= bcd2bin(buf[4]);
+	dt->tm_mon	= bcd2bin(buf[5] & 0x1F) - 1;
+	dt->tm_year	= bcd2bin(buf[6]) + 100; /* year offset from 1900 */
+
+	return 0;
+}
+
+static int ds1343_set_time(struct device *dev, struct rtc_time *dt)
+{
+	struct ds1343_priv *priv = dev_get_drvdata(dev);
+	u8 buf[7];
+
+	buf[0] = bin2bcd(dt->tm_sec);
+	buf[1] = bin2bcd(dt->tm_min);
+	buf[2] = bin2bcd(dt->tm_hour) & 0x3F;
+	buf[3] = bin2bcd(dt->tm_wday + 1);
+	buf[4] = bin2bcd(dt->tm_mday);
+	buf[5] = bin2bcd(dt->tm_mon + 1);
+	buf[6] = bin2bcd(dt->tm_year - 100);
+
+	return regmap_bulk_write(priv->map, DS1343_SECONDS_REG,
+				 buf, sizeof(buf));
+}
+
+static int ds1343_read_alarm(struct device *dev, struct rtc_wkalrm *alarm)
+{
+	struct ds1343_priv *priv = dev_get_drvdata(dev);
+	unsigned char buf[4];
+	unsigned int val;
+	int res;
+
+	if (priv->irq <= 0)
+		return -EINVAL;
+
+	res = regmap_read(priv->map, DS1343_STATUS_REG, &val);
+	if (res)
+		return res;
+
+	alarm->pending = !!(val & DS1343_IRQF0);
+
+	res = regmap_read(priv->map, DS1343_CONTROL_REG, &val);
+	if (res)
+		return res;
+	alarm->enabled = !!(val & DS1343_A0IE);
+
+	res = regmap_bulk_read(priv->map, DS1343_ALM0_SEC_REG, buf, 4);
+	if (res)
+		return res;
+
+	alarm->time.tm_sec = bcd2bin(buf[0]) & 0x7f;
+	alarm->time.tm_min = bcd2bin(buf[1]) & 0x7f;
+	alarm->time.tm_hour = bcd2bin(buf[2]) & 0x3f;
+	alarm->time.tm_mday = bcd2bin(buf[3]) & 0x3f;
+
+	return 0;
+}
+
+static int ds1343_set_alarm(struct device *dev, struct rtc_wkalrm *alarm)
+{
+	struct ds1343_priv *priv = dev_get_drvdata(dev);
+	unsigned char buf[4];
+	int res = 0;
+
+	if (priv->irq <= 0)
+		return -EINVAL;
+
+	res = regmap_update_bits(priv->map, DS1343_CONTROL_REG, DS1343_A0IE, 0);
+	if (res)
+		return res;
+
+	buf[0] = bin2bcd(alarm->time.tm_sec);
+	buf[1] = bin2bcd(alarm->time.tm_min);
+	buf[2] = bin2bcd(alarm->time.tm_hour);
+	buf[3] = bin2bcd(alarm->time.tm_mday);
+
+	res = regmap_bulk_write(priv->map, DS1343_ALM0_SEC_REG, buf, 4);
+	if (res)
+		return res;
+
+	if (alarm->enabled)
+		res = regmap_update_bits(priv->map, DS1343_CONTROL_REG,
+					 DS1343_A0IE, DS1343_A0IE);
+
+	return res;
+}
+
+static int ds1343_alarm_irq_enable(struct device *dev, unsigned int enabled)
+{
+	struct ds1343_priv *priv = dev_get_drvdata(dev);
+
+	if (priv->irq <= 0)
+		return -EINVAL;
+
+	return regmap_update_bits(priv->map, DS1343_CONTROL_REG,
+				  DS1343_A0IE, enabled ? DS1343_A0IE : 0);
+}
+
+static irqreturn_t ds1343_thread(int irq, void *dev_id)
+{
+	struct ds1343_priv *priv = dev_id;
+	unsigned int stat;
+	int res = 0;
+
+	rtc_lock(priv->rtc);
+
+	res = regmap_read(priv->map, DS1343_STATUS_REG, &stat);
+	if (res)
+		goto out;
+
+	if (stat & DS1343_IRQF0) {
+		stat &= ~DS1343_IRQF0;
+		regmap_write(priv->map, DS1343_STATUS_REG, stat);
+
+		rtc_update_irq(priv->rtc, 1, RTC_AF | RTC_IRQF);
+
+		regmap_update_bits(priv->map, DS1343_CONTROL_REG,
+				   DS1343_A0IE, 0);
+	}
+
+out:
+	rtc_unlock(priv->rtc);
+	return IRQ_HANDLED;
+}
+
+static const struct rtc_class_ops ds1343_rtc_ops = {
+	.read_time	= ds1343_read_time,
+	.set_time	= ds1343_set_time,
+	.read_alarm	= ds1343_read_alarm,
+	.set_alarm	= ds1343_set_alarm,
+	.alarm_irq_enable = ds1343_alarm_irq_enable,
+};
+
+static int ds1343_probe(struct spi_device *spi)
+{
+	struct ds1343_priv *priv;
+	struct regmap_config config = { .reg_bits = 8, .val_bits = 8,
+					.write_flag_mask = 0x80, };
+	unsigned int data;
+	int res;
+	struct nvmem_config nvmem_cfg = {
+		.name = "ds1343-",
+		.word_size = 1,
+		.stride = 1,
+		.size = DS1343_NVRAM_LEN,
+		.reg_read = ds1343_nvram_read,
+		.reg_write = ds1343_nvram_write,
+	};
+
+	priv = devm_kzalloc(&spi->dev, sizeof(struct ds1343_priv), GFP_KERNEL);
+	if (!priv)
+		return -ENOMEM;
+
+	/* RTC DS1347 works in spi mode 3 and
+	 * its chip select is active high. Active high should be defined as
+	 * "inverse polarity" as GPIO-based chip selects can be logically
+	 * active high but inverted by the GPIO library.
+	 */
+	spi->mode |= SPI_MODE_3;
+	spi->mode ^= SPI_CS_HIGH;
+	spi->bits_per_word = 8;
+	res = spi_setup(spi);
+	if (res)
+		return res;
+
+	spi_set_drvdata(spi, priv);
+
+	priv->map = devm_regmap_init_spi(spi, &config);
+
+	if (IS_ERR(priv->map)) {
+		dev_err(&spi->dev, "spi regmap init failed for rtc ds1343\n");
+		return PTR_ERR(priv->map);
+	}
+
+	res = regmap_read(priv->map, DS1343_SECONDS_REG, &data);
+	if (res)
+		return res;
+
+	regmap_read(priv->map, DS1343_CONTROL_REG, &data);
+	data |= DS1343_INTCN;
+	data &= ~(DS1343_EOSC | DS1343_A1IE | DS1343_A0IE);
+	regmap_write(priv->map, DS1343_CONTROL_REG, data);
+
+	regmap_read(priv->map, DS1343_STATUS_REG, &data);
+	data &= ~(DS1343_OSF | DS1343_IRQF1 | DS1343_IRQF0);
+	regmap_write(priv->map, DS1343_STATUS_REG, data);
+
+	priv->rtc = devm_rtc_allocate_device(&spi->dev);
+	if (IS_ERR(priv->rtc))
+		return PTR_ERR(priv->rtc);
+
+	priv->rtc->ops = &ds1343_rtc_ops;
+	priv->rtc->range_min = RTC_TIMESTAMP_BEGIN_2000;
+	priv->rtc->range_max = RTC_TIMESTAMP_END_2099;
+
+	res = rtc_add_group(priv->rtc, &ds1343_attr_group);
+	if (res)
+		dev_err(&spi->dev,
+			"unable to create sysfs entries for rtc ds1343\n");
+
+	res = devm_rtc_register_device(priv->rtc);
+	if (res)
+		return res;
+
+	nvmem_cfg.priv = priv;
+	devm_rtc_nvmem_register(priv->rtc, &nvmem_cfg);
+
+	priv->irq = spi->irq;
+
+	if (priv->irq >= 0) {
+		res = devm_request_threaded_irq(&spi->dev, spi->irq, NULL,
+						ds1343_thread, IRQF_ONESHOT,
+						"ds1343", priv);
+		if (res) {
+			priv->irq = -1;
+			dev_err(&spi->dev,
+				"unable to request irq for rtc ds1343\n");
+		} else {
+			device_init_wakeup(&spi->dev, true);
+			devm_pm_set_wake_irq(&spi->dev, spi->irq);
+		}
+	}
+
+	return 0;
+}
+
+#ifdef CONFIG_PM_SLEEP
+
+static int ds1343_suspend(struct device *dev)
+{
+	struct spi_device *spi = to_spi_device(dev);
+
+	if (spi->irq >= 0 && device_may_wakeup(dev))
+		enable_irq_wake(spi->irq);
+
+	return 0;
+}
+
+static int ds1343_resume(struct device *dev)
+{
+	struct spi_device *spi = to_spi_device(dev);
+
+	if (spi->irq >= 0 && device_may_wakeup(dev))
+		disable_irq_wake(spi->irq);
+
+	return 0;
+}
+
+#endif
+
+static SIMPLE_DEV_PM_OPS(ds1343_pm, ds1343_suspend, ds1343_resume);
+
+static struct spi_driver ds1343_driver = {
+	.driver = {
+		.name = "ds1343",
+		.pm = &ds1343_pm,
+	},
+	.probe = ds1343_probe,
+	.id_table = ds1343_id,
+};
+
+module_spi_driver(ds1343_driver);
+
+MODULE_DESCRIPTION("DS1343 RTC SPI Driver");
+MODULE_AUTHOR("Raghavendra Chandra Ganiga <ravi23ganiga@gmail.com>,"
+		"Ankur Srivastava <sankurece@gmail.com>");
+MODULE_LICENSE("GPL v2");