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, 501 insertions, 0 deletions

diff --git a/drivers/hwmon/isl28022.c b/drivers/hwmon/isl28022.c
new file mode 100644
index 000000000..0c60d2ef2
--- /dev/null
+++ b/drivers/hwmon/isl28022.c
@@ -0,0 +1,501 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * isl28022.c - driver for Renesas ISL28022 power monitor chip monitoring
+ *
+ * Copyright (c) 2023 Carsten Spieß <mail@carsten-spiess.de>
+ */
+
+#include <linux/debugfs.h>
+#include <linux/err.h>
+#include <linux/hwmon.h>
+#include <linux/i2c.h>
+#include <linux/math64.h>
+#include <linux/module.h>
+#include <linux/regmap.h>
+
+/* ISL28022 registers */
+#define ISL28022_REG_CONFIG	0x00
+#define ISL28022_REG_SHUNT	0x01
+#define ISL28022_REG_BUS	0x02
+#define ISL28022_REG_POWER	0x03
+#define ISL28022_REG_CURRENT	0x04
+#define ISL28022_REG_CALIB	0x05
+#define ISL28022_REG_SHUNT_THR	0x06
+#define ISL28022_REG_BUS_THR	0x07
+#define ISL28022_REG_INT	0x08
+#define ISL28022_REG_AUX	0x09
+#define ISL28022_REG_MAX	ISL28022_REG_AUX
+
+/* ISL28022 config flags */
+/* mode flags */
+#define ISL28022_MODE_SHIFT	0
+#define ISL28022_MODE_MASK	0x0007
+
+#define ISL28022_MODE_PWR_DOWN	0x0
+#define ISL28022_MODE_TRG_S	0x1
+#define ISL28022_MODE_TRG_B	0x2
+#define ISL28022_MODE_TRG_SB	0x3
+#define ISL28022_MODE_ADC_OFF	0x4
+#define ISL28022_MODE_CONT_S	0x5
+#define ISL28022_MODE_CONT_B	0x6
+#define ISL28022_MODE_CONT_SB	0x7
+
+/* shunt ADC settings */
+#define ISL28022_SADC_SHIFT	3
+#define ISL28022_SADC_MASK	0x0078
+
+#define ISL28022_BADC_SHIFT	7
+#define ISL28022_BADC_MASK	0x0780
+
+#define ISL28022_ADC_12		0x0	/* 12 bit ADC */
+#define ISL28022_ADC_13		0x1	/* 13 bit ADC */
+#define ISL28022_ADC_14		0x2	/* 14 bit ADC */
+#define ISL28022_ADC_15		0x3	/* 15 bit ADC */
+#define ISL28022_ADC_15_1	0x8	/* 15 bit ADC, 1 sample */
+#define ISL28022_ADC_15_2	0x9	/* 15 bit ADC, 2 samples */
+#define ISL28022_ADC_15_4	0xA	/* 15 bit ADC, 4 samples */
+#define ISL28022_ADC_15_8	0xB	/* 15 bit ADC, 8 samples */
+#define ISL28022_ADC_15_16	0xC	/* 15 bit ADC, 16 samples */
+#define ISL28022_ADC_15_32	0xD	/* 15 bit ADC, 32 samples */
+#define ISL28022_ADC_15_64	0xE	/* 15 bit ADC, 64 samples */
+#define ISL28022_ADC_15_128	0xF	/* 15 bit ADC, 128 samples */
+
+/* shunt voltage range */
+#define ISL28022_PG_SHIFT	11
+#define ISL28022_PG_MASK	0x1800
+
+#define ISL28022_PG_40		0x0	/* +/-40 mV */
+#define ISL28022_PG_80		0x1	/* +/-80 mV */
+#define ISL28022_PG_160		0x2	/* +/-160 mV */
+#define ISL28022_PG_320		0x3	/* +/-3200 mV */
+
+/* bus voltage range */
+#define ISL28022_BRNG_SHIFT	13
+#define ISL28022_BRNG_MASK	0x6000
+
+#define ISL28022_BRNG_16	0x0	/* 16 V */
+#define ISL28022_BRNG_32	0x1	/* 32 V */
+#define ISL28022_BRNG_60	0x3	/* 60 V */
+
+/* reset */
+#define ISL28022_RESET		0x8000
+
+struct isl28022_data {
+	struct regmap		*regmap;
+	u32			shunt;
+	u32			gain;
+	u32			average;
+};
+
+static int isl28022_read_in(struct device *dev, u32 attr, int channel, long *val)
+{
+	struct isl28022_data *data = dev_get_drvdata(dev);
+	unsigned int regval;
+	int err;
+	u16 sign_bit;
+
+	switch (channel) {
+	case 0:
+		switch (attr) {
+		case hwmon_in_input:
+			err = regmap_read(data->regmap,
+					  ISL28022_REG_BUS, &regval);
+			if (err < 0)
+				return err;
+			/* driver supports only 60V mode (BRNG 11) */
+			*val = (long)(((u16)regval) & 0xFFFC);
+			break;
+		default:
+			return -EOPNOTSUPP;
+		}
+		break;
+	case 1:
+		switch (attr) {
+		case hwmon_in_input:
+			err = regmap_read(data->regmap,
+					  ISL28022_REG_SHUNT, &regval);
+			if (err < 0)
+				return err;
+			switch (data->gain) {
+			case 8:
+				sign_bit = (regval >> 15) & 0x01;
+				*val = (long)((((u16)regval) & 0x7FFF) -
+					(sign_bit * 32768)) / 100;
+				break;
+			case 4:
+				sign_bit = (regval >> 14) & 0x01;
+				*val = (long)((((u16)regval) & 0x3FFF) -
+					(sign_bit * 16384)) / 100;
+				break;
+			case 2:
+				sign_bit = (regval >> 13) & 0x01;
+				*val = (long)((((u16)regval) & 0x1FFF) -
+					(sign_bit * 8192)) / 100;
+				break;
+			case 1:
+				sign_bit = (regval >> 12) & 0x01;
+				*val = (long)((((u16)regval) & 0x0FFF) -
+					(sign_bit * 4096)) / 100;
+				break;
+			}
+			break;
+		default:
+			return -EOPNOTSUPP;
+		}
+		break;
+	default:
+		return -EOPNOTSUPP;
+	}
+
+	return 0;
+}
+
+static int isl28022_read_current(struct device *dev, u32 attr, long *val)
+{
+	struct isl28022_data *data = dev_get_drvdata(dev);
+	unsigned int regval;
+	int err;
+	u16 sign_bit;
+
+	switch (attr) {
+	case hwmon_curr_input:
+		err = regmap_read(data->regmap,
+				  ISL28022_REG_CURRENT, &regval);
+		if (err < 0)
+			return err;
+		sign_bit = (regval >> 15) & 0x01;
+		*val = (((long)(((u16)regval) & 0x7FFF) - (sign_bit * 32768)) *
+			1250L * (long)data->gain) / (long)data->shunt;
+		break;
+	default:
+		return -EOPNOTSUPP;
+	}
+
+	return 0;
+}
+
+static int isl28022_read_power(struct device *dev, u32 attr, long *val)
+{
+	struct isl28022_data *data = dev_get_drvdata(dev);
+	unsigned int regval;
+	int err;
+
+	switch (attr) {
+	case hwmon_power_input:
+		err = regmap_read(data->regmap,
+				  ISL28022_REG_POWER, &regval);
+		if (err < 0)
+			return err;
+		*val = min(div_u64(51200000ULL * data->gain * regval,
+				   data->shunt), LONG_MAX);
+		break;
+	default:
+		return -EOPNOTSUPP;
+	}
+
+	return 0;
+}
+
+static int isl28022_read(struct device *dev, enum hwmon_sensor_types type,
+			 u32 attr, int channel, long *val)
+{
+	switch (type) {
+	case hwmon_in:
+		return isl28022_read_in(dev, attr, channel, val);
+	case hwmon_curr:
+		return isl28022_read_current(dev, attr, val);
+	case hwmon_power:
+		return isl28022_read_power(dev, attr, val);
+	default:
+		return -EOPNOTSUPP;
+	}
+	return 0;
+}
+
+static umode_t isl28022_is_visible(const void *data, enum hwmon_sensor_types type,
+				   u32 attr, int channel)
+{
+	switch (type) {
+	case hwmon_in:
+		switch (attr) {
+		case hwmon_in_input:
+			return 0444;
+		default:
+			break;
+		}
+		break;
+	case hwmon_curr:
+		switch (attr) {
+		case hwmon_curr_input:
+			return 0444;
+		default:
+			break;
+		}
+		break;
+	case hwmon_power:
+		switch (attr) {
+		case hwmon_power_input:
+			return 0444;
+		default:
+			break;
+		}
+		break;
+	default:
+		break;
+	}
+	return 0;
+}
+
+static const struct hwmon_channel_info *isl28022_info[] = {
+	HWMON_CHANNEL_INFO(in,
+			   HWMON_I_INPUT,	/* channel 0: bus voltage (mV) */
+			   HWMON_I_INPUT),	/* channel 1: shunt voltage (mV) */
+	HWMON_CHANNEL_INFO(curr,
+			   HWMON_C_INPUT),	/* channel 1: current (mA) */
+	HWMON_CHANNEL_INFO(power,
+			   HWMON_P_INPUT),	/* channel 1: power (µW) */
+	NULL
+};
+
+static const struct hwmon_ops isl28022_hwmon_ops = {
+	.is_visible = isl28022_is_visible,
+	.read = isl28022_read,
+};
+
+static const struct hwmon_chip_info isl28022_chip_info = {
+	.ops = &isl28022_hwmon_ops,
+	.info = isl28022_info,
+};
+
+static bool isl28022_is_writeable_reg(struct device *dev, unsigned int reg)
+{
+	switch (reg) {
+	case ISL28022_REG_CONFIG:
+	case ISL28022_REG_CALIB:
+	case ISL28022_REG_SHUNT_THR:
+	case ISL28022_REG_BUS_THR:
+	case ISL28022_REG_INT:
+	case ISL28022_REG_AUX:
+		return true;
+	}
+
+	return false;
+}
+
+static bool isl28022_is_volatile_reg(struct device *dev, unsigned int reg)
+{
+	switch (reg) {
+	case ISL28022_REG_CONFIG:
+	case ISL28022_REG_SHUNT:
+	case ISL28022_REG_BUS:
+	case ISL28022_REG_POWER:
+	case ISL28022_REG_CURRENT:
+	case ISL28022_REG_INT:
+	case ISL28022_REG_AUX:
+		return true;
+	}
+	return true;
+}
+
+static const struct regmap_config isl28022_regmap_config = {
+	.reg_bits = 8,
+	.val_bits = 16,
+	.max_register = ISL28022_REG_MAX,
+	.writeable_reg = isl28022_is_writeable_reg,
+	.volatile_reg = isl28022_is_volatile_reg,
+	.val_format_endian = REGMAP_ENDIAN_BIG,
+	.cache_type = REGCACHE_MAPLE,
+	.use_single_read = true,
+	.use_single_write = true,
+};
+
+static int shunt_voltage_show(struct seq_file *seqf, void *unused)
+{
+	struct isl28022_data *data = seqf->private;
+	unsigned int regval;
+	int err;
+
+	err = regmap_read(data->regmap,
+			  ISL28022_REG_SHUNT, &regval);
+	if (err)
+		return err;
+
+	/* print shunt voltage in micro volt  */
+	seq_printf(seqf, "%d\n", regval * 10);
+
+	return 0;
+}
+DEFINE_SHOW_ATTRIBUTE(shunt_voltage);
+
+/*
+ * read property values and make consistency checks.
+ *
+ * following values for shunt range and resistor are allowed:
+ *   40 mV -> gain 1, shunt min.  800 micro ohms
+ *   80 mV -> gain 2, shunt min. 1600 micro ohms
+ *  160 mV -> gain 4, shunt min. 3200 micro ohms
+ *  320 mV -> gain 8, shunt min. 6400 micro ohms
+ */
+static int isl28022_read_properties(struct device *dev, struct isl28022_data *data)
+{
+	const char *propname;
+	u32 val;
+	int err;
+
+	propname = "shunt-resistor-micro-ohms";
+	if (device_property_present(dev, propname)) {
+		err = device_property_read_u32(dev, propname, &val);
+		if (err)
+			return err;
+	} else {
+		val = 10000;
+	}
+	data->shunt = val;
+
+	propname = "renesas,shunt-range-microvolt";
+	if (device_property_present(dev, propname)) {
+		err = device_property_read_u32(dev, propname, &val);
+		if (err)
+			return err;
+	} else {
+		val = 320000;
+	}
+
+	switch (val) {
+	case 40000:
+		data->gain = 1;
+		if (data->shunt < 800)
+			goto shunt_invalid;
+		break;
+	case 80000:
+		data->gain = 2;
+		if (data->shunt < 1600)
+			goto shunt_invalid;
+		break;
+	case 160000:
+		data->gain = 4;
+		if (data->shunt < 3200)
+			goto shunt_invalid;
+		break;
+	case 320000:
+		data->gain = 8;
+		if (data->shunt < 6400)
+			goto shunt_invalid;
+		break;
+	default:
+		return dev_err_probe(dev, -EINVAL, "%s invalid value %u\n", propname, val);
+	}
+
+	propname = "renesas,average-samples";
+	if (device_property_present(dev, propname)) {
+		err = device_property_read_u32(dev, propname, &val);
+		if (err)
+			return err;
+	} else {
+		val = 1;
+	}
+	if (val > 128 || hweight32(val) != 1)
+		return dev_err_probe(dev, -EINVAL, "%s invalid value %u\n", propname, val);
+
+	data->average = val;
+
+	return 0;
+
+shunt_invalid:
+	return dev_err_probe(dev, -EINVAL,
+			     "renesas,shunt-resistor-microvolt invalid value %d\n",
+			     data->shunt);
+}
+
+/*
+ * write configuration and calibration registers
+ *
+ * The driver supports only shunt and bus continuous ADC mode at 15bit resolution
+ * with averaging from 1 to 128 samples (pow of 2) on both channels.
+ * Shunt voltage gain 1,2,4 or 8 is allowed.
+ * The bus voltage range is 60V fixed.
+ */
+static int isl28022_config(struct isl28022_data *data)
+{
+	int err;
+	u16 config;
+	u16 calib;
+
+	config = (ISL28022_MODE_CONT_SB << ISL28022_MODE_SHIFT) |
+			(ISL28022_BRNG_60 << ISL28022_BRNG_SHIFT) |
+			(__ffs(data->gain) << ISL28022_PG_SHIFT) |
+			((ISL28022_ADC_15_1 + __ffs(data->average)) << ISL28022_SADC_SHIFT) |
+			((ISL28022_ADC_15_1 + __ffs(data->average)) << ISL28022_BADC_SHIFT);
+
+	calib = data->shunt ? 0x8000 / data->gain : 0;
+
+	err = regmap_write(data->regmap, ISL28022_REG_CONFIG, config);
+	if (err < 0)
+		return err;
+
+	return regmap_write(data->regmap, ISL28022_REG_CALIB, calib);
+}
+
+static int isl28022_probe(struct i2c_client *client)
+{
+	struct device *dev = &client->dev;
+	struct device *hwmon_dev;
+	struct isl28022_data *data;
+	int err;
+
+	if (!i2c_check_functionality(client->adapter,
+				     I2C_FUNC_SMBUS_BYTE_DATA |
+				     I2C_FUNC_SMBUS_WORD_DATA))
+		return -ENODEV;
+
+	data = devm_kzalloc(dev, sizeof(struct isl28022_data), GFP_KERNEL);
+	if (!data)
+		return -ENOMEM;
+
+	err = isl28022_read_properties(dev, data);
+	if (err)
+		return err;
+
+	data->regmap = devm_regmap_init_i2c(client, &isl28022_regmap_config);
+	if (IS_ERR(data->regmap))
+		return PTR_ERR(data->regmap);
+
+	err = isl28022_config(data);
+	if (err)
+		return err;
+
+	debugfs_create_file("shunt_voltage", 0444, client->debugfs, data, &shunt_voltage_fops);
+
+	hwmon_dev = devm_hwmon_device_register_with_info(dev, client->name,
+							 data, &isl28022_chip_info, NULL);
+	if (IS_ERR(hwmon_dev))
+		return PTR_ERR(hwmon_dev);
+
+	return 0;
+}
+
+static const struct i2c_device_id isl28022_ids[] = {
+	{ .name = "isl28022" },
+	{ /* LIST END */ }
+};
+MODULE_DEVICE_TABLE(i2c, isl28022_ids);
+
+static const struct of_device_id __maybe_unused isl28022_of_match[] = {
+	{ .compatible = "renesas,isl28022"},
+	{ /* LIST END */ }
+};
+MODULE_DEVICE_TABLE(of, isl28022_of_match);
+
+static struct i2c_driver isl28022_driver = {
+	.class		= I2C_CLASS_HWMON,
+	.driver = {
+		.name	= "isl28022",
+	},
+	.probe	= isl28022_probe,
+	.id_table	= isl28022_ids,
+};
+module_i2c_driver(isl28022_driver);
+
+MODULE_AUTHOR("Carsten Spieß <mail@carsten-spiess.de>");
+MODULE_DESCRIPTION("ISL28022 driver");
+MODULE_LICENSE("GPL");