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, 483 insertions, 0 deletions

diff --git a/drivers/hwmon/tmp421.c b/drivers/hwmon/tmp421.c
new file mode 100644
index 000000000..ed00ccfdd
--- /dev/null
+++ b/drivers/hwmon/tmp421.c
@@ -0,0 +1,483 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/* tmp421.c
+ *
+ * Copyright (C) 2009 Andre Prendel <andre.prendel@gmx.de>
+ * Preliminary support by:
+ * Melvin Rook, Raymond Ng
+ */
+
+/*
+ * Driver for the Texas Instruments TMP421 SMBus temperature sensor IC.
+ * Supported models: TMP421, TMP422, TMP423, TMP441, TMP442
+ */
+
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/slab.h>
+#include <linux/jiffies.h>
+#include <linux/i2c.h>
+#include <linux/hwmon.h>
+#include <linux/hwmon-sysfs.h>
+#include <linux/err.h>
+#include <linux/of.h>
+#include <linux/sysfs.h>
+
+/* Addresses to scan */
+static const unsigned short normal_i2c[] = { 0x2a, 0x4c, 0x4d, 0x4e, 0x4f,
+					     I2C_CLIENT_END };
+
+enum chips { tmp421, tmp422, tmp423, tmp441, tmp442 };
+
+#define MAX_CHANNELS				4
+/* The TMP421 registers */
+#define TMP421_STATUS_REG			0x08
+#define TMP421_CONFIG_REG_1			0x09
+#define TMP421_CONFIG_REG_2			0x0A
+#define TMP421_CONFIG_REG_REN(x)		(BIT(3 + (x)))
+#define TMP421_CONFIG_REG_REN_MASK		GENMASK(6, 3)
+#define TMP421_CONVERSION_RATE_REG		0x0B
+#define TMP421_N_FACTOR_REG_1			0x21
+#define TMP421_MANUFACTURER_ID_REG		0xFE
+#define TMP421_DEVICE_ID_REG			0xFF
+
+static const u8 TMP421_TEMP_MSB[MAX_CHANNELS]	= { 0x00, 0x01, 0x02, 0x03 };
+static const u8 TMP421_TEMP_LSB[MAX_CHANNELS]	= { 0x10, 0x11, 0x12, 0x13 };
+
+/* Flags */
+#define TMP421_CONFIG_SHUTDOWN			0x40
+#define TMP421_CONFIG_RANGE			0x04
+
+/* Manufacturer / Device ID's */
+#define TMP421_MANUFACTURER_ID			0x55
+#define TMP421_DEVICE_ID			0x21
+#define TMP422_DEVICE_ID			0x22
+#define TMP423_DEVICE_ID			0x23
+#define TMP441_DEVICE_ID			0x41
+#define TMP442_DEVICE_ID			0x42
+
+static const struct i2c_device_id tmp421_id[] = {
+	{ .name = "tmp421", .driver_data = 2 },
+	{ .name = "tmp422", .driver_data = 3 },
+	{ .name = "tmp423", .driver_data = 4 },
+	{ .name = "tmp441", .driver_data = 2 },
+	{ .name = "tmp442", .driver_data = 3 },
+	{ }
+};
+MODULE_DEVICE_TABLE(i2c, tmp421_id);
+
+static const struct of_device_id __maybe_unused tmp421_of_match[] = {
+	{
+		.compatible = "ti,tmp421",
+		.data = (void *)2
+	},
+	{
+		.compatible = "ti,tmp422",
+		.data = (void *)3
+	},
+	{
+		.compatible = "ti,tmp423",
+		.data = (void *)4
+	},
+	{
+		.compatible = "ti,tmp441",
+		.data = (void *)2
+	},
+	{
+		.compatible = "ti,tmp442",
+		.data = (void *)3
+	},
+	{ },
+};
+MODULE_DEVICE_TABLE(of, tmp421_of_match);
+
+struct tmp421_channel {
+	const char *label;
+	bool enabled;
+	s16 temp;
+};
+
+struct tmp421_data {
+	struct i2c_client *client;
+	u32 temp_config[MAX_CHANNELS + 1];
+	struct hwmon_channel_info temp_info;
+	const struct hwmon_channel_info *info[2];
+	struct hwmon_chip_info chip;
+	bool valid;
+	unsigned long last_updated;
+	unsigned long channels;
+	u8 config;
+	struct tmp421_channel channel[MAX_CHANNELS];
+};
+
+static int temp_from_raw(u16 reg, bool extended)
+{
+	/* Mask out status bits */
+	int temp = reg & ~0xf;
+
+	if (extended)
+		temp = temp - 64 * 256;
+	else
+		temp = (s16)temp;
+
+	return DIV_ROUND_CLOSEST(temp * 1000, 256);
+}
+
+static int tmp421_update_device(struct tmp421_data *data)
+{
+	struct i2c_client *client = data->client;
+	int ret = 0;
+	int i;
+
+	if (time_after(jiffies, data->last_updated + (HZ / 2)) ||
+	    !data->valid) {
+		data->valid = false;
+		ret = i2c_smbus_read_byte_data(client, TMP421_CONFIG_REG_1);
+		if (ret < 0)
+			return ret;
+		data->config = ret;
+
+		for (i = 0; i < data->channels; i++) {
+			ret = i2c_smbus_read_byte_data(client, TMP421_TEMP_MSB[i]);
+			if (ret < 0)
+				return ret;
+			data->channel[i].temp = ret << 8;
+
+			ret = i2c_smbus_read_byte_data(client, TMP421_TEMP_LSB[i]);
+			if (ret < 0)
+				return ret;
+			data->channel[i].temp |= ret;
+		}
+		data->last_updated = jiffies;
+		data->valid = true;
+	}
+	return 0;
+}
+
+static int tmp421_enable_channels(struct tmp421_data *data)
+{
+	int err;
+	struct i2c_client *client = data->client;
+	struct device *dev = &client->dev;
+	int old = i2c_smbus_read_byte_data(client, TMP421_CONFIG_REG_2);
+	int new, i;
+
+	if (old < 0) {
+		dev_err(dev, "error reading register, can't disable channels\n");
+		return old;
+	}
+
+	new = old & ~TMP421_CONFIG_REG_REN_MASK;
+	for (i = 0; i < data->channels; i++)
+		if (data->channel[i].enabled)
+			new |= TMP421_CONFIG_REG_REN(i);
+
+	if (new == old)
+		return 0;
+
+	err = i2c_smbus_write_byte_data(client, TMP421_CONFIG_REG_2, new);
+	if (err < 0)
+		dev_err(dev, "error writing register, can't disable channels\n");
+
+	return err;
+}
+
+static int tmp421_read(struct device *dev, enum hwmon_sensor_types type,
+		       u32 attr, int channel, long *val)
+{
+	struct tmp421_data *tmp421 = dev_get_drvdata(dev);
+	int ret = 0;
+
+	ret = tmp421_update_device(tmp421);
+	if (ret)
+		return ret;
+
+	switch (attr) {
+	case hwmon_temp_input:
+		if (!tmp421->channel[channel].enabled)
+			return -ENODATA;
+		*val = temp_from_raw(tmp421->channel[channel].temp,
+				     tmp421->config & TMP421_CONFIG_RANGE);
+		return 0;
+	case hwmon_temp_fault:
+		if (!tmp421->channel[channel].enabled)
+			return -ENODATA;
+		/*
+		 * Any of OPEN or /PVLD bits indicate a hardware mulfunction
+		 * and the conversion result may be incorrect
+		 */
+		*val = !!(tmp421->channel[channel].temp & 0x03);
+		return 0;
+	case hwmon_temp_enable:
+		*val = tmp421->channel[channel].enabled;
+		return 0;
+	default:
+		return -EOPNOTSUPP;
+	}
+
+}
+
+static int tmp421_read_string(struct device *dev, enum hwmon_sensor_types type,
+			     u32 attr, int channel, const char **str)
+{
+	struct tmp421_data *data = dev_get_drvdata(dev);
+
+	*str = data->channel[channel].label;
+
+	return 0;
+}
+
+static int tmp421_write(struct device *dev, enum hwmon_sensor_types type,
+			u32 attr, int channel, long val)
+{
+	struct tmp421_data *data = dev_get_drvdata(dev);
+	int ret;
+
+	switch (attr) {
+	case hwmon_temp_enable:
+		data->channel[channel].enabled = val;
+		ret = tmp421_enable_channels(data);
+		break;
+	default:
+	    ret = -EOPNOTSUPP;
+	}
+
+	return ret;
+}
+
+static umode_t tmp421_is_visible(const void *data, enum hwmon_sensor_types type,
+				 u32 attr, int channel)
+{
+	switch (attr) {
+	case hwmon_temp_fault:
+	case hwmon_temp_input:
+	case hwmon_temp_label:
+		return 0444;
+	case hwmon_temp_enable:
+		return 0644;
+	default:
+		return 0;
+	}
+}
+
+static int tmp421_init_client(struct tmp421_data *data)
+{
+	int config, config_orig;
+	struct i2c_client *client = data->client;
+
+	/* Set the conversion rate to 2 Hz */
+	i2c_smbus_write_byte_data(client, TMP421_CONVERSION_RATE_REG, 0x05);
+
+	/* Start conversions (disable shutdown if necessary) */
+	config = i2c_smbus_read_byte_data(client, TMP421_CONFIG_REG_1);
+	if (config < 0) {
+		dev_err(&client->dev,
+			"Could not read configuration register (%d)\n", config);
+		return config;
+	}
+
+	config_orig = config;
+	config &= ~TMP421_CONFIG_SHUTDOWN;
+
+	if (config != config_orig) {
+		dev_info(&client->dev, "Enable monitoring chip\n");
+		i2c_smbus_write_byte_data(client, TMP421_CONFIG_REG_1, config);
+	}
+
+	return tmp421_enable_channels(data);
+}
+
+static int tmp421_detect(struct i2c_client *client,
+			 struct i2c_board_info *info)
+{
+	enum chips kind;
+	struct i2c_adapter *adapter = client->adapter;
+	static const char * const names[] = {
+		"TMP421", "TMP422", "TMP423",
+		"TMP441", "TMP442"
+	};
+	int addr = client->addr;
+	u8 reg;
+
+	if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE_DATA))
+		return -ENODEV;
+
+	reg = i2c_smbus_read_byte_data(client, TMP421_MANUFACTURER_ID_REG);
+	if (reg != TMP421_MANUFACTURER_ID)
+		return -ENODEV;
+
+	reg = i2c_smbus_read_byte_data(client, TMP421_CONVERSION_RATE_REG);
+	if (reg & 0xf8)
+		return -ENODEV;
+
+	reg = i2c_smbus_read_byte_data(client, TMP421_STATUS_REG);
+	if (reg & 0x7f)
+		return -ENODEV;
+
+	reg = i2c_smbus_read_byte_data(client, TMP421_DEVICE_ID_REG);
+	switch (reg) {
+	case TMP421_DEVICE_ID:
+		kind = tmp421;
+		break;
+	case TMP422_DEVICE_ID:
+		if (addr == 0x2a)
+			return -ENODEV;
+		kind = tmp422;
+		break;
+	case TMP423_DEVICE_ID:
+		if (addr != 0x4c && addr != 0x4d)
+			return -ENODEV;
+		kind = tmp423;
+		break;
+	case TMP441_DEVICE_ID:
+		kind = tmp441;
+		break;
+	case TMP442_DEVICE_ID:
+		if (addr != 0x4c && addr != 0x4d)
+			return -ENODEV;
+		kind = tmp442;
+		break;
+	default:
+		return -ENODEV;
+	}
+
+	strscpy(info->type, tmp421_id[kind].name, I2C_NAME_SIZE);
+	dev_info(&adapter->dev, "Detected TI %s chip at 0x%02x\n",
+		 names[kind], client->addr);
+
+	return 0;
+}
+
+static int tmp421_probe_child_from_dt(struct i2c_client *client,
+				      struct device_node *child,
+				      struct tmp421_data *data)
+
+{
+	struct device *dev = &client->dev;
+	u32 i;
+	s32 val;
+	int err;
+
+	err = of_property_read_u32(child, "reg", &i);
+	if (err) {
+		dev_err(dev, "missing reg property of %pOFn\n", child);
+		return err;
+	}
+
+	if (i >= data->channels) {
+		dev_err(dev, "invalid reg %d of %pOFn\n", i, child);
+		return -EINVAL;
+	}
+
+	err = of_property_read_string(child, "label", &data->channel[i].label);
+	if (err == -ENODATA || err == -EILSEQ) {
+		dev_err(dev, "invalid label property in %pOFn\n", child);
+		return err;
+	}
+	if (data->channel[i].label)
+		data->temp_config[i] |= HWMON_T_LABEL;
+
+	data->channel[i].enabled = of_device_is_available(child);
+
+	err = of_property_read_s32(child, "ti,n-factor", &val);
+	if (!err) {
+		if (i == 0) {
+			dev_err(dev, "n-factor can't be set for internal channel\n");
+			return -EINVAL;
+		}
+
+		if (val > 127 || val < -128) {
+			dev_err(dev, "n-factor for channel %d invalid (%d)\n",
+				i, val);
+			return -EINVAL;
+		}
+		i2c_smbus_write_byte_data(client, TMP421_N_FACTOR_REG_1 + i - 1,
+					  val);
+	}
+
+	return 0;
+}
+
+static int tmp421_probe_from_dt(struct i2c_client *client, struct tmp421_data *data)
+{
+	struct device *dev = &client->dev;
+	const struct device_node *np = dev->of_node;
+	int err;
+
+	for_each_child_of_node_scoped(np, child) {
+		if (strcmp(child->name, "channel"))
+			continue;
+
+		err = tmp421_probe_child_from_dt(client, child, data);
+		if (err)
+			return err;
+	}
+
+	return 0;
+}
+
+static const struct hwmon_ops tmp421_ops = {
+	.is_visible = tmp421_is_visible,
+	.read = tmp421_read,
+	.read_string = tmp421_read_string,
+	.write = tmp421_write,
+};
+
+static int tmp421_probe(struct i2c_client *client)
+{
+	struct device *dev = &client->dev;
+	struct device *hwmon_dev;
+	struct tmp421_data *data;
+	int i, err;
+
+	data = devm_kzalloc(dev, sizeof(struct tmp421_data), GFP_KERNEL);
+	if (!data)
+		return -ENOMEM;
+
+	data->channels = (unsigned long)i2c_get_match_data(client);
+	data->client = client;
+
+	for (i = 0; i < data->channels; i++) {
+		data->temp_config[i] = HWMON_T_INPUT | HWMON_T_FAULT | HWMON_T_ENABLE;
+		data->channel[i].enabled = true;
+	}
+
+	err = tmp421_probe_from_dt(client, data);
+	if (err)
+		return err;
+
+	err = tmp421_init_client(data);
+	if (err)
+		return err;
+
+	data->chip.ops = &tmp421_ops;
+	data->chip.info = data->info;
+
+	data->info[0] = &data->temp_info;
+
+	data->temp_info.type = hwmon_temp;
+	data->temp_info.config = data->temp_config;
+
+	hwmon_dev = devm_hwmon_device_register_with_info(dev, client->name,
+							 data,
+							 &data->chip,
+							 NULL);
+	return PTR_ERR_OR_ZERO(hwmon_dev);
+}
+
+static struct i2c_driver tmp421_driver = {
+	.class = I2C_CLASS_HWMON,
+	.driver = {
+		.name	= "tmp421",
+		.of_match_table = of_match_ptr(tmp421_of_match),
+	},
+	.probe = tmp421_probe,
+	.id_table = tmp421_id,
+	.detect = tmp421_detect,
+	.address_list = normal_i2c,
+};
+
+module_i2c_driver(tmp421_driver);
+
+MODULE_AUTHOR("Andre Prendel <andre.prendel@gmx.de>");
+MODULE_DESCRIPTION("Texas Instruments TMP421/422/423/441/442 temperature sensor driver");
+MODULE_LICENSE("GPL");