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/input/touchscreen/exc3000.c b/drivers/input/touchscreen/exc3000.c
new file mode 100644
index 000000000..037bb3523
--- /dev/null
+++ b/drivers/input/touchscreen/exc3000.c
@@ -0,0 +1,477 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Driver for I2C connected EETI EXC3000 multiple touch controller
+ *
+ * Copyright (C) 2017 Ahmet Inan <inan@distec.de>
+ *
+ * minimal implementation based on egalax_ts.c and egalax_i2c.c
+ */
+
+#include <linux/acpi.h>
+#include <linux/bitops.h>
+#include <linux/delay.h>
+#include <linux/device.h>
+#include <linux/gpio/consumer.h>
+#include <linux/i2c.h>
+#include <linux/input.h>
+#include <linux/input/mt.h>
+#include <linux/input/touchscreen.h>
+#include <linux/interrupt.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/regulator/consumer.h>
+#include <linux/sizes.h>
+#include <linux/timer.h>
+#include <linux/unaligned.h>
+
+#define EXC3000_NUM_SLOTS		10
+#define EXC3000_SLOTS_PER_FRAME		5
+#define EXC3000_LEN_FRAME		66
+#define EXC3000_LEN_VENDOR_REQUEST	68
+#define EXC3000_LEN_POINT		10
+
+#define EXC3000_LEN_MODEL_NAME		16
+#define EXC3000_LEN_FW_VERSION		16
+
+#define EXC3000_VENDOR_EVENT		0x03
+#define EXC3000_MT1_EVENT		0x06
+#define EXC3000_MT2_EVENT		0x18
+
+#define EXC3000_TIMEOUT_MS		100
+
+#define EXC3000_RESET_MS		10
+#define EXC3000_READY_MS		100
+
+static const struct i2c_device_id exc3000_id[];
+
+struct eeti_dev_info {
+	const char *name;
+	int max_xy;
+};
+
+enum eeti_dev_id {
+	EETI_EXC3000,
+	EETI_EXC80H60,
+	EETI_EXC80H84,
+	EETI_EXC81W32,
+};
+
+static struct eeti_dev_info exc3000_info[] = {
+	[EETI_EXC3000] = {
+		.name = "EETI EXC3000 Touch Screen",
+		.max_xy = SZ_4K - 1,
+	},
+	[EETI_EXC80H60] = {
+		.name = "EETI EXC80H60 Touch Screen",
+		.max_xy = SZ_16K - 1,
+	},
+	[EETI_EXC80H84] = {
+		.name = "EETI EXC80H84 Touch Screen",
+		.max_xy = SZ_16K - 1,
+	},
+	[EETI_EXC81W32] = {
+		.name = "EETI EXC81W32 Touch Screen",
+		.max_xy = SZ_16K - 1,
+	},
+};
+
+struct exc3000_data {
+	struct i2c_client *client;
+	const struct eeti_dev_info *info;
+	struct input_dev *input;
+	struct touchscreen_properties prop;
+	struct gpio_desc *reset;
+	struct timer_list timer;
+	u8 buf[2 * EXC3000_LEN_FRAME];
+	struct completion wait_event;
+	struct mutex query_lock;
+};
+
+static void exc3000_report_slots(struct input_dev *input,
+				 struct touchscreen_properties *prop,
+				 const u8 *buf, int num)
+{
+	for (; num--; buf += EXC3000_LEN_POINT) {
+		if (buf[0] & BIT(0)) {
+			input_mt_slot(input, buf[1]);
+			input_mt_report_slot_state(input, MT_TOOL_FINGER, true);
+			touchscreen_report_pos(input, prop,
+					       get_unaligned_le16(buf + 2),
+					       get_unaligned_le16(buf + 4),
+					       true);
+		}
+	}
+}
+
+static void exc3000_timer(struct timer_list *t)
+{
+	struct exc3000_data *data = timer_container_of(data, t, timer);
+
+	input_mt_sync_frame(data->input);
+	input_sync(data->input);
+}
+
+static inline void exc3000_schedule_timer(struct exc3000_data *data)
+{
+	mod_timer(&data->timer, jiffies + msecs_to_jiffies(EXC3000_TIMEOUT_MS));
+}
+
+static void exc3000_shutdown_timer(void *timer)
+{
+	timer_shutdown_sync(timer);
+}
+
+static int exc3000_read_frame(struct exc3000_data *data, u8 *buf)
+{
+	struct i2c_client *client = data->client;
+	int ret;
+
+	ret = i2c_master_send(client, "'", 2);
+	if (ret < 0)
+		return ret;
+
+	if (ret != 2)
+		return -EIO;
+
+	ret = i2c_master_recv(client, buf, EXC3000_LEN_FRAME);
+	if (ret < 0)
+		return ret;
+
+	if (ret != EXC3000_LEN_FRAME)
+		return -EIO;
+
+	if (get_unaligned_le16(buf) != EXC3000_LEN_FRAME)
+		return -EINVAL;
+
+	return 0;
+}
+
+static int exc3000_handle_mt_event(struct exc3000_data *data)
+{
+	struct input_dev *input = data->input;
+	int ret, total_slots;
+	u8 *buf = data->buf;
+
+	total_slots = buf[3];
+	if (!total_slots || total_slots > EXC3000_NUM_SLOTS) {
+		ret = -EINVAL;
+		goto out_fail;
+	}
+
+	if (total_slots > EXC3000_SLOTS_PER_FRAME) {
+		/* Read 2nd frame to get the rest of the contacts. */
+		ret = exc3000_read_frame(data, buf + EXC3000_LEN_FRAME);
+		if (ret)
+			goto out_fail;
+
+		/* 2nd chunk must have number of contacts set to 0. */
+		if (buf[EXC3000_LEN_FRAME + 3] != 0) {
+			ret = -EINVAL;
+			goto out_fail;
+		}
+	}
+
+	/*
+	 * We read full state successfully, no contacts will be "stuck".
+	 */
+	timer_delete_sync(&data->timer);
+
+	while (total_slots > 0) {
+		int slots = min(total_slots, EXC3000_SLOTS_PER_FRAME);
+
+		exc3000_report_slots(input, &data->prop, buf + 4, slots);
+		total_slots -= slots;
+		buf += EXC3000_LEN_FRAME;
+	}
+
+	input_mt_sync_frame(input);
+	input_sync(input);
+
+	return 0;
+
+out_fail:
+	/* Schedule a timer to release "stuck" contacts */
+	exc3000_schedule_timer(data);
+
+	return ret;
+}
+
+static irqreturn_t exc3000_interrupt(int irq, void *dev_id)
+{
+	struct exc3000_data *data = dev_id;
+	u8 *buf = data->buf;
+	int ret;
+
+	ret = exc3000_read_frame(data, buf);
+	if (ret) {
+		/* Schedule a timer to release "stuck" contacts */
+		exc3000_schedule_timer(data);
+		goto out;
+	}
+
+	switch (buf[2]) {
+	case EXC3000_VENDOR_EVENT:
+		complete(&data->wait_event);
+		break;
+
+	case EXC3000_MT1_EVENT:
+	case EXC3000_MT2_EVENT:
+		exc3000_handle_mt_event(data);
+		break;
+
+	default:
+		break;
+	}
+
+out:
+	return IRQ_HANDLED;
+}
+
+static int exc3000_vendor_data_request(struct exc3000_data *data, u8 *request,
+				       u8 request_len, u8 *response, int timeout)
+{
+	u8 buf[EXC3000_LEN_VENDOR_REQUEST] = { 0x67, 0x00, 0x42, 0x00, 0x03 };
+	int ret;
+	unsigned long time_left;
+
+	guard(mutex)(&data->query_lock);
+
+	reinit_completion(&data->wait_event);
+
+	buf[5] = request_len;
+	memcpy(&buf[6], request, request_len);
+
+	ret = i2c_master_send(data->client, buf, EXC3000_LEN_VENDOR_REQUEST);
+	if (ret < 0)
+		return ret;
+
+	time_left = wait_for_completion_timeout(&data->wait_event,
+						timeout * HZ);
+	if (time_left == 0)
+		return -ETIMEDOUT;
+
+	if (data->buf[3] >= EXC3000_LEN_FRAME)
+		return -ENOSPC;
+
+	memcpy(response, &data->buf[4], data->buf[3]);
+	return data->buf[3];
+}
+
+static ssize_t fw_version_show(struct device *dev,
+			       struct device_attribute *attr, char *buf)
+{
+	struct i2c_client *client = to_i2c_client(dev);
+	struct exc3000_data *data = i2c_get_clientdata(client);
+	u8 response[EXC3000_LEN_FRAME];
+	int ret;
+
+	/* query bootloader info */
+	ret = exc3000_vendor_data_request(data,
+					  (u8[]){0x39, 0x02}, 2, response, 1);
+	if (ret < 0)
+		return ret;
+
+	/*
+	 * If the bootloader version is non-zero then the device is in
+	 * bootloader mode and won't answer a query for the application FW
+	 * version, so we just use the bootloader version info.
+	 */
+	if (response[2] || response[3])
+		return sprintf(buf, "%d.%d\n", response[2], response[3]);
+
+	ret = exc3000_vendor_data_request(data, (u8[]){'D'}, 1, response, 1);
+	if (ret < 0)
+		return ret;
+
+	return sprintf(buf, "%s\n", &response[1]);
+}
+static DEVICE_ATTR_RO(fw_version);
+
+static ssize_t model_show(struct device *dev,
+			  struct device_attribute *attr, char *buf)
+{
+	struct i2c_client *client = to_i2c_client(dev);
+	struct exc3000_data *data = i2c_get_clientdata(client);
+	u8 response[EXC3000_LEN_FRAME];
+	int ret;
+
+	ret = exc3000_vendor_data_request(data, (u8[]){'E'}, 1, response, 1);
+	if (ret < 0)
+		return ret;
+
+	return sprintf(buf, "%s\n", &response[1]);
+}
+static DEVICE_ATTR_RO(model);
+
+static ssize_t type_show(struct device *dev,
+			  struct device_attribute *attr, char *buf)
+{
+	struct i2c_client *client = to_i2c_client(dev);
+	struct exc3000_data *data = i2c_get_clientdata(client);
+	u8 response[EXC3000_LEN_FRAME];
+	int ret;
+
+	ret = exc3000_vendor_data_request(data, (u8[]){'F'}, 1, response, 1);
+	if (ret < 0)
+		return ret;
+
+	return sprintf(buf, "%s\n", &response[1]);
+}
+static DEVICE_ATTR_RO(type);
+
+static struct attribute *exc3000_attrs[] = {
+	&dev_attr_fw_version.attr,
+	&dev_attr_model.attr,
+	&dev_attr_type.attr,
+	NULL
+};
+ATTRIBUTE_GROUPS(exc3000);
+
+static int exc3000_probe(struct i2c_client *client)
+{
+	struct exc3000_data *data;
+	struct input_dev *input;
+	int error, max_xy, retry;
+
+	data = devm_kzalloc(&client->dev, sizeof(*data), GFP_KERNEL);
+	if (!data)
+		return -ENOMEM;
+
+	data->client = client;
+	data->info = device_get_match_data(&client->dev);
+	if (!data->info) {
+		enum eeti_dev_id eeti_dev_id =
+			i2c_match_id(exc3000_id, client)->driver_data;
+		data->info = &exc3000_info[eeti_dev_id];
+	}
+	timer_setup(&data->timer, exc3000_timer, 0);
+	init_completion(&data->wait_event);
+	mutex_init(&data->query_lock);
+
+	data->reset = devm_gpiod_get_optional(&client->dev, "reset",
+					      GPIOD_OUT_HIGH);
+	if (IS_ERR(data->reset))
+		return PTR_ERR(data->reset);
+
+	/* For proper reset sequence, enable power while reset asserted */
+	error = devm_regulator_get_enable(&client->dev, "vdd");
+	if (error && error != -ENODEV)
+		return dev_err_probe(&client->dev, error,
+				     "failed to request vdd regulator\n");
+
+	if (data->reset) {
+		msleep(EXC3000_RESET_MS);
+		gpiod_set_value_cansleep(data->reset, 0);
+		msleep(EXC3000_READY_MS);
+	}
+
+	input = devm_input_allocate_device(&client->dev);
+	if (!input)
+		return -ENOMEM;
+
+	data->input = input;
+	input_set_drvdata(input, data);
+
+	input->name = data->info->name;
+	input->id.bustype = BUS_I2C;
+
+	max_xy = data->info->max_xy;
+	input_set_abs_params(input, ABS_MT_POSITION_X, 0, max_xy, 0, 0);
+	input_set_abs_params(input, ABS_MT_POSITION_Y, 0, max_xy, 0, 0);
+
+	touchscreen_parse_properties(input, true, &data->prop);
+
+	error = input_mt_init_slots(input, EXC3000_NUM_SLOTS,
+				    INPUT_MT_DIRECT | INPUT_MT_DROP_UNUSED);
+	if (error)
+		return error;
+
+	error = input_register_device(input);
+	if (error)
+		return error;
+
+	error = devm_add_action_or_reset(&client->dev, exc3000_shutdown_timer,
+					 &data->timer);
+	if (error)
+		return error;
+
+	error = devm_request_threaded_irq(&client->dev, client->irq,
+					  NULL, exc3000_interrupt, IRQF_ONESHOT,
+					  client->name, data);
+	if (error)
+		return error;
+
+	/*
+	 * I²C does not have built-in recovery, so retry on failure. This
+	 * ensures, that the device probe will not fail for temporary issues
+	 * on the bus.  This is not needed for the sysfs calls (userspace
+	 * will receive the error code and can start another query) and
+	 * cannot be done for touch events (but that only means loosing one
+	 * or two touch events anyways).
+	 */
+	for (retry = 0; retry < 3; retry++) {
+		u8 response[EXC3000_LEN_FRAME];
+
+		error = exc3000_vendor_data_request(data, (u8[]){'E'}, 1,
+						    response, 1);
+		if (error > 0) {
+			dev_dbg(&client->dev, "TS Model: %s", &response[1]);
+			error = 0;
+			break;
+		}
+		dev_warn(&client->dev, "Retry %d get EETI EXC3000 model: %d\n",
+			 retry + 1, error);
+	}
+
+	if (error)
+		return error;
+
+	i2c_set_clientdata(client, data);
+
+	return 0;
+}
+
+static const struct i2c_device_id exc3000_id[] = {
+	{ .name = "exc3000", .driver_data = EETI_EXC3000 },
+	{ .name = "exc80h60", .driver_data = EETI_EXC80H60 },
+	{ .name = "exc80h84", .driver_data = EETI_EXC80H84 },
+	{ .name = "exc81w32", .driver_data = EETI_EXC81W32 },
+	{ }
+};
+MODULE_DEVICE_TABLE(i2c, exc3000_id);
+
+#ifdef CONFIG_OF
+static const struct of_device_id exc3000_of_match[] = {
+	{ .compatible = "eeti,exc3000", .data = &exc3000_info[EETI_EXC3000] },
+	{ .compatible = "eeti,exc80h60", .data = &exc3000_info[EETI_EXC80H60] },
+	{ .compatible = "eeti,exc80h84", .data = &exc3000_info[EETI_EXC80H84] },
+	{ .compatible = "eeti,exc81w32", .data = &exc3000_info[EETI_EXC81W32] },
+	{ }
+};
+MODULE_DEVICE_TABLE(of, exc3000_of_match);
+#endif
+
+#ifdef CONFIG_ACPI
+static const struct acpi_device_id exc3000_acpi_match[] = {
+	{ "EGA00001", .driver_data = (kernel_ulong_t)&exc3000_info[EETI_EXC80H60] },
+	{ }
+};
+MODULE_DEVICE_TABLE(acpi, exc3000_acpi_match);
+#endif
+
+static struct i2c_driver exc3000_driver = {
+	.driver = {
+		.name	= "exc3000",
+		.dev_groups = exc3000_groups,
+		.of_match_table = of_match_ptr(exc3000_of_match),
+		.acpi_match_table = ACPI_PTR(exc3000_acpi_match),
+	},
+	.id_table	= exc3000_id,
+	.probe		= exc3000_probe,
+};
+
+module_i2c_driver(exc3000_driver);
+
+MODULE_AUTHOR("Ahmet Inan <inan@distec.de>");
+MODULE_DESCRIPTION("I2C connected EETI EXC3000 multiple touch controller driver");
+MODULE_LICENSE("GPL v2");