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authorLinus Torvalds <torvalds@linux-foundation.org>2026-08-23 13:28:57 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2026-08-23 13:28:57 -0700
commit4352b8aee98005853aa63f57d6377282de17a33f (patch)
tree27614d7a9ef05c32d089004e104364ce42324837 /drivers/input/touchscreen.c
downloadlinux-stable-4352b8aee98005853aa63f57d6377282de17a33f.tar.gz
linux-stable-4352b8aee98005853aa63f57d6377282de17a33f.zip
Merge tag 'i3c/for-7.3' of git://git.kernel.org/pub/scm/linux/kernel/git/i3c/linuxgrafted
Pull I3C updates from Alexandre Belloni: "A new driver this cycle, for the AMD AXI I3C controller. There are also new features such as IBI wakeup support, SETAASA device discovery and ACPI support for the the DAA methods, meaning we can now communicate with the SPD devices on DDR5 modules. New driver: - AMD AXI I3C master controller Subsystem: - I3C Common Command Code (CCC) handling improvements, especially around GET CCCs - SETAASA device discovery support - ACPI support for all existing DAA methods like SETDASA, SETNEWDA as well as I2C devices on I3C bus - IBI-based wakeup support Drivers: - dw: SETAASA support - mipi-i3c-hci: advertise IBI wakeup capability, AMD_PT I3C controller support, PIO queue management support for HCI v1.2 - renesas: improve suspend to RAM support, add runtime PM support" * tag 'i3c/for-7.3' of git://git.kernel.org/pub/scm/linux/kernel/git/i3c/linux: (70 commits) i3c: dw: reduce do_daa time if there's no client i3c: mipi-i3c-hci: Add support for AMD_PT I3C controller i3c: mipi-i3c-hci: Add PIO queue management support for HCI v1.2 i3c: mipi-i3c-hci: Fix missing STAT_IBI_STATUS_THLD in PIO mode i3c: dw: rename "pclk" to "apb" to match dt-binding i3c: dw: make struct dw_i3c_cmd smaller i3c: dw: use COMMAND_PORT_TRANSFER_ARG instead of hardcoding i3c: renesas: Don't register devices when ENTDAA times out i3c: master: dw-i3c-master: fix OD timing for first broadcast i3c: mipi-i3c-hci: Advertise IBI wakeup capability i3c: mipi-i3c-hci: Factor out i3c_hci_sysdev() i3c: mipi-i3c-hci-pci: Propagate I3C wakeup requirements to PCI i3c: master: Reject IBI requests from non-IBI-capable devices i3c: master: Add helper to query bus wakeup requirements i3c: master: Report wakeup events for IBIs i3c: master: Support IBI-based wakeup capability i3c: master: Fix potential UAF in i3c_device_match() i3c: master: Fix potential UAF in i3c_device_uevent() i3c: Make dev->desc locking assumptions explicit i3c: master: Fix use-after-free of master->this ...
Diffstat (limited to 'drivers/input/touchscreen.c')
-rw-r--r--drivers/input/touchscreen.c208
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");