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, 208 insertions, 0 deletions

diff --git a/drivers/mfd/da9052-i2c.c b/drivers/mfd/da9052-i2c.c
new file mode 100644
index 000000000..fd000a21b
--- /dev/null
+++ b/drivers/mfd/da9052-i2c.c
@@ -0,0 +1,208 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * I2C access for DA9052 PMICs.
+ *
+ * Copyright(c) 2011 Dialog Semiconductor Ltd.
+ *
+ * Author: David Dajun Chen <dchen@diasemi.com>
+ */
+
+#include <linux/device.h>
+#include <linux/module.h>
+#include <linux/input.h>
+#include <linux/mfd/core.h>
+#include <linux/i2c.h>
+#include <linux/err.h>
+#include <linux/of.h>
+
+#include <linux/mfd/da9052/da9052.h>
+#include <linux/mfd/da9052/reg.h>
+
+
+/* I2C safe register check */
+static inline bool i2c_safe_reg(unsigned char reg)
+{
+	switch (reg) {
+	case DA9052_STATUS_A_REG:
+	case DA9052_STATUS_B_REG:
+	case DA9052_STATUS_C_REG:
+	case DA9052_STATUS_D_REG:
+	case DA9052_ADC_RES_L_REG:
+	case DA9052_ADC_RES_H_REG:
+	case DA9052_VDD_RES_REG:
+	case DA9052_ICHG_AV_REG:
+	case DA9052_TBAT_RES_REG:
+	case DA9052_ADCIN4_RES_REG:
+	case DA9052_ADCIN5_RES_REG:
+	case DA9052_ADCIN6_RES_REG:
+	case DA9052_TJUNC_RES_REG:
+	case DA9052_TSI_X_MSB_REG:
+	case DA9052_TSI_Y_MSB_REG:
+	case DA9052_TSI_LSB_REG:
+	case DA9052_TSI_Z_MSB_REG:
+		return true;
+	default:
+		return false;
+	}
+}
+
+/*
+ * There is an issue with DA9052 and DA9053_AA/BA/BB PMIC where the PMIC
+ * gets lockup up or fails to respond following a system reset.
+ * This fix is to follow any read or write with a dummy read to a safe
+ * register.
+ */
+static int da9052_i2c_fix(struct da9052 *da9052, unsigned char reg)
+{
+	int val;
+
+	switch (da9052->chip_id) {
+	case DA9052:
+	case DA9053_AA:
+	case DA9053_BA:
+	case DA9053_BB:
+		/* A dummy read to a safe register address. */
+		if (!i2c_safe_reg(reg))
+			return regmap_read(da9052->regmap,
+					   DA9052_PARK_REGISTER,
+					   &val);
+		break;
+	case DA9053_BC:
+	default:
+		/*
+		 * For other chips parking of I2C register
+		 * to a safe place is not required.
+		 */
+		break;
+	}
+
+	return 0;
+}
+
+/*
+ * According to errata item 24, multiwrite mode should be avoided
+ * in order to prevent register data corruption after power-down.
+ */
+static int da9052_i2c_disable_multiwrite(struct da9052 *da9052)
+{
+	int reg_val, ret;
+
+	ret = regmap_read(da9052->regmap, DA9052_CONTROL_B_REG, &reg_val);
+	if (ret < 0)
+		return ret;
+
+	if (!(reg_val & DA9052_CONTROL_B_WRITEMODE)) {
+		reg_val |= DA9052_CONTROL_B_WRITEMODE;
+		ret = regmap_write(da9052->regmap, DA9052_CONTROL_B_REG,
+				   reg_val);
+		if (ret < 0)
+			return ret;
+	}
+
+	return 0;
+}
+
+static const struct i2c_device_id da9052_i2c_id[] = {
+	{"da9052", DA9052},
+	{"da9053-aa", DA9053_AA},
+	{"da9053-ba", DA9053_BA},
+	{"da9053-bb", DA9053_BB},
+	{"da9053-bc", DA9053_BC},
+	{}
+};
+MODULE_DEVICE_TABLE(i2c, da9052_i2c_id);
+
+#ifdef CONFIG_OF
+static const struct of_device_id dialog_dt_ids[] = {
+	{ .compatible = "dlg,da9052", .data = &da9052_i2c_id[0] },
+	{ .compatible = "dlg,da9053-aa", .data = &da9052_i2c_id[1] },
+	{ .compatible = "dlg,da9053-ba", .data = &da9052_i2c_id[2] },
+	{ .compatible = "dlg,da9053-bb", .data = &da9052_i2c_id[3] },
+	{ .compatible = "dlg,da9053-bc", .data = &da9052_i2c_id[4] },
+	{ /* sentinel */ }
+};
+#endif
+
+static int da9052_i2c_probe(struct i2c_client *client)
+{
+	const struct i2c_device_id *id = i2c_client_get_device_id(client);
+	struct da9052 *da9052;
+	int ret;
+
+	da9052 = devm_kzalloc(&client->dev, sizeof(struct da9052), GFP_KERNEL);
+	if (!da9052)
+		return -ENOMEM;
+
+	da9052->dev = &client->dev;
+	da9052->chip_irq = client->irq;
+	da9052->fix_io = da9052_i2c_fix;
+
+	i2c_set_clientdata(client, da9052);
+
+	da9052->regmap = devm_regmap_init_i2c(client, &da9052_regmap_config);
+	if (IS_ERR(da9052->regmap)) {
+		ret = PTR_ERR(da9052->regmap);
+		dev_err(&client->dev, "Failed to allocate register map: %d\n",
+			ret);
+		return ret;
+	}
+
+	ret = da9052_i2c_disable_multiwrite(da9052);
+	if (ret < 0)
+		return ret;
+
+#ifdef CONFIG_OF
+	if (!id)
+		id = of_device_get_match_data(&client->dev);
+#endif
+
+	if (!id) {
+		ret = -ENODEV;
+		dev_err(&client->dev, "id is null.\n");
+		return ret;
+	}
+
+	return da9052_device_init(da9052, id->driver_data);
+}
+
+static void da9052_i2c_remove(struct i2c_client *client)
+{
+	struct da9052 *da9052 = i2c_get_clientdata(client);
+
+	da9052_device_exit(da9052);
+}
+
+static struct i2c_driver da9052_i2c_driver = {
+	.probe = da9052_i2c_probe,
+	.remove = da9052_i2c_remove,
+	.id_table = da9052_i2c_id,
+	.driver = {
+		.name = "da9052",
+#ifdef CONFIG_OF
+		.of_match_table = dialog_dt_ids,
+#endif
+	},
+};
+
+static int __init da9052_i2c_init(void)
+{
+	int ret;
+
+	ret = i2c_add_driver(&da9052_i2c_driver);
+	if (ret != 0) {
+		pr_err("DA9052 I2C registration failed %d\n", ret);
+		return ret;
+	}
+
+	return 0;
+}
+subsys_initcall(da9052_i2c_init);
+
+static void __exit da9052_i2c_exit(void)
+{
+	i2c_del_driver(&da9052_i2c_driver);
+}
+module_exit(da9052_i2c_exit);
+
+MODULE_AUTHOR("David Dajun Chen <dchen@diasemi.com>");
+MODULE_DESCRIPTION("I2C driver for Dialog DA9052 PMIC");