Merge branches 'expcb.2026.07.24a', 'misc.2026.07.30a', 'rcu-tasks.2026.07.30a', 'srcu.2026.08.11a' and 'torture.2026.08.14a' into HEADgrafted

Changes:

Make expedited grace periods expedite normal RCU callbacks

Miscellaneous fixes:
 * Improve diagnostic output with character task states.
 * Mark accesses to inform KCSAN of concurrency design.
 * Move from kmalloc() to kmalloc_obj().
 * Documentation updates.
 * Improve handling of RCU deferred quiescent states.
 * Clean up unused function arguments and structure fields.
 * Reduce show_rcu_gp_kthreads() stack space.

Tasks RCU updates:
 * Clean up after SRCU re-implementation of Tasks Trace RCU.
 * Mark accesses to inform KCSAN of concurrency design.
 * Add ->lazy_timer status to diagnostic output.
 * Remove an unnecessary memory barrier.
 * Fix a data race, courtesy of KCSAN.
 * Documentation updates.
 * Convert cond_resched_tasks_rcu_qs() from macro to static inline
   function.

SRCU updates:
 * Add Rust helpers for SRCU.
 * Avoid losing queued work at cleanup_srcu_struct() time.

Torture-test updates:
 * Preparation work for immediate RCU priority deboosting.
 * Test RCU readers from real interrupt handlers (as opposed to softirq).
 * Simplify code through use of cpumask_next_wrap().
 * Improve diagnostic output with character task states.
 * Add rcutorture.nwriters parameter to allow lightweight stall testing,
   and rcutorture.stall_only to make doing so easier.
 * Test an RCU Tasks Trace grace period implying an RCU grace period.
 * Make RCU Tasks Trace torturing track reader batches.
 * Fix a data race, courtesy of KCSAN.
 * Plug a shuffle_tmp_mask memory leak on kthread spawn failure.

1 files changed, 208 insertions, 0 deletions

diff --git a/drivers/input/touchscreen.c b/drivers/input/touchscreen.c
new file mode 100644
index 000000000..d699b24bb
--- /dev/null
+++ b/drivers/input/touchscreen.c
@@ -0,0 +1,208 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ *  Generic helper functions for touchscreens and other two-dimensional
+ *  pointing devices
+ *
+ *  Copyright (c) 2014 Sebastian Reichel <sre@kernel.org>
+ */
+
+#include <linux/export.h>
+#include <linux/property.h>
+#include <linux/input.h>
+#include <linux/input/mt.h>
+#include <linux/input/touchscreen.h>
+#include <linux/module.h>
+
+static bool touchscreen_get_prop_u32(struct device *dev,
+				     const char *property,
+				     unsigned int default_value,
+				     unsigned int *value)
+{
+	u32 val;
+	int error;
+
+	error = device_property_read_u32(dev, property, &val);
+	if (error) {
+		*value = default_value;
+		return false;
+	}
+
+	*value = val;
+	return true;
+}
+
+static void touchscreen_set_params(struct input_dev *dev,
+				   unsigned long axis,
+				   int min, int max, int fuzz)
+{
+	struct input_absinfo *absinfo;
+
+	if (!test_bit(axis, dev->absbit)) {
+		dev_warn(&dev->dev,
+			 "Parameters are specified but the axis %lu is not set up\n",
+			 axis);
+		return;
+	}
+
+	absinfo = &dev->absinfo[axis];
+	absinfo->minimum = min;
+	absinfo->maximum = max;
+	absinfo->fuzz = fuzz;
+}
+
+/**
+ * touchscreen_parse_properties - parse common touchscreen properties
+ * @input: input device that should be parsed
+ * @multitouch: specifies whether parsed properties should be applied to
+ *	single-touch or multi-touch axes
+ * @prop: pointer to a struct touchscreen_properties into which to store
+ *	axis swap and invert info for use with touchscreen_report_x_y();
+ *	or %NULL
+ *
+ * This function parses common properties for touchscreens and sets up the
+ * input device accordingly. The function keeps previously set up default
+ * values if no value is specified.
+ */
+void touchscreen_parse_properties(struct input_dev *input, bool multitouch,
+				  struct touchscreen_properties *prop)
+{
+	struct device *dev = input->dev.parent;
+	struct input_absinfo *absinfo;
+	unsigned int axis, axis_x, axis_y;
+	unsigned int minimum, maximum, fuzz;
+	bool data_present;
+
+	input_alloc_absinfo(input);
+	if (!input->absinfo)
+		return;
+
+	axis_x = multitouch ? ABS_MT_POSITION_X : ABS_X;
+	axis_y = multitouch ? ABS_MT_POSITION_Y : ABS_Y;
+
+	data_present = touchscreen_get_prop_u32(dev, "touchscreen-min-x",
+						input_abs_get_min(input, axis_x),
+						&minimum);
+	data_present |= touchscreen_get_prop_u32(dev, "touchscreen-size-x",
+						 input_abs_get_max(input,
+								   axis_x) + 1,
+						 &maximum);
+	data_present |= touchscreen_get_prop_u32(dev, "touchscreen-fuzz-x",
+						 input_abs_get_fuzz(input, axis_x),
+						 &fuzz);
+	if (data_present)
+		touchscreen_set_params(input, axis_x, minimum, maximum - 1, fuzz);
+
+	data_present = touchscreen_get_prop_u32(dev, "touchscreen-min-y",
+						input_abs_get_min(input, axis_y),
+						&minimum);
+	data_present |= touchscreen_get_prop_u32(dev, "touchscreen-size-y",
+						 input_abs_get_max(input,
+								   axis_y) + 1,
+						 &maximum);
+	data_present |= touchscreen_get_prop_u32(dev, "touchscreen-fuzz-y",
+						 input_abs_get_fuzz(input, axis_y),
+						 &fuzz);
+	if (data_present)
+		touchscreen_set_params(input, axis_y, minimum, maximum - 1, fuzz);
+
+	axis = multitouch ? ABS_MT_PRESSURE : ABS_PRESSURE;
+	data_present = touchscreen_get_prop_u32(dev,
+						"touchscreen-max-pressure",
+						input_abs_get_max(input, axis),
+						&maximum);
+	data_present |= touchscreen_get_prop_u32(dev,
+						 "touchscreen-fuzz-pressure",
+						 input_abs_get_fuzz(input, axis),
+						 &fuzz);
+	if (data_present)
+		touchscreen_set_params(input, axis, 0, maximum, fuzz);
+
+	if (!prop)
+		return;
+
+	prop->max_x = input_abs_get_max(input, axis_x);
+	prop->max_y = input_abs_get_max(input, axis_y);
+
+	prop->invert_x =
+		device_property_read_bool(dev, "touchscreen-inverted-x");
+	if (prop->invert_x) {
+		absinfo = &input->absinfo[axis_x];
+		absinfo->maximum -= absinfo->minimum;
+		absinfo->minimum = 0;
+	}
+
+	prop->invert_y =
+		device_property_read_bool(dev, "touchscreen-inverted-y");
+	if (prop->invert_y) {
+		absinfo = &input->absinfo[axis_y];
+		absinfo->maximum -= absinfo->minimum;
+		absinfo->minimum = 0;
+	}
+
+	prop->swap_x_y =
+		device_property_read_bool(dev, "touchscreen-swapped-x-y");
+	if (prop->swap_x_y)
+		swap(input->absinfo[axis_x], input->absinfo[axis_y]);
+}
+EXPORT_SYMBOL(touchscreen_parse_properties);
+
+static void
+touchscreen_apply_prop_to_x_y(const struct touchscreen_properties *prop,
+			      unsigned int *x, unsigned int *y)
+{
+	if (prop->invert_x)
+		*x = prop->max_x - *x;
+
+	if (prop->invert_y)
+		*y = prop->max_y - *y;
+
+	if (prop->swap_x_y)
+		swap(*x, *y);
+}
+
+/**
+ * touchscreen_set_mt_pos - Set input_mt_pos coordinates
+ * @pos: input_mt_pos to set coordinates of
+ * @prop: pointer to a struct touchscreen_properties
+ * @x: X coordinate to store in pos
+ * @y: Y coordinate to store in pos
+ *
+ * Adjust the passed in x and y values applying any axis inversion and
+ * swapping requested in the passed in touchscreen_properties and store
+ * the result in a struct input_mt_pos.
+ */
+void touchscreen_set_mt_pos(struct input_mt_pos *pos,
+			    const struct touchscreen_properties *prop,
+			    unsigned int x, unsigned int y)
+{
+	touchscreen_apply_prop_to_x_y(prop, &x, &y);
+	pos->x = x;
+	pos->y = y;
+}
+EXPORT_SYMBOL(touchscreen_set_mt_pos);
+
+/**
+ * touchscreen_report_pos - Report touchscreen coordinates
+ * @input: input_device to report coordinates for
+ * @prop: pointer to a struct touchscreen_properties
+ * @x: X coordinate to report
+ * @y: Y coordinate to report
+ * @multitouch: Report coordinates on single-touch or multi-touch axes
+ *
+ * Adjust the passed in x and y values applying any axis inversion and
+ * swapping requested in the passed in touchscreen_properties and then
+ * report the resulting coordinates on the input_dev's x and y axis.
+ */
+void touchscreen_report_pos(struct input_dev *input,
+			    const struct touchscreen_properties *prop,
+			    unsigned int x, unsigned int y,
+			    bool multitouch)
+{
+	touchscreen_apply_prop_to_x_y(prop, &x, &y);
+	input_report_abs(input, multitouch ? ABS_MT_POSITION_X : ABS_X, x);
+	input_report_abs(input, multitouch ? ABS_MT_POSITION_Y : ABS_Y, y);
+}
+EXPORT_SYMBOL(touchscreen_report_pos);
+
+MODULE_LICENSE("GPL v2");
+MODULE_DESCRIPTION("Helper functions for touchscreens and other devices");