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authorLinus Torvalds <torvalds@linux-foundation.org>2026-08-19 10:09:22 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2026-08-19 10:09:22 -0700
commitf4cdf7ca9a1fdcca413157df19753f388a5a224e (patch)
tree60a31895b2446cd7fa27514e8c2843534a0de0da /drivers/input/touchscreen.c
downloadlinux-stable-f4cdf7ca9a1fdcca413157df19753f388a5a224e.tar.gz
linux-stable-f4cdf7ca9a1fdcca413157df19753f388a5a224e.zip
Merge tag 'media/v7.3-1' of git://git.kernel.org/pub/scm/linux/kernel/git/mchehab/linux-mediagrafted
Pull media updates from Mauro Carvalho Chehab: - v4l2-core: added ISP statistics support and per-block validation - v4l2-core: Allow unknown HDR10 white point and luminance - New camera sensors: Sony IMX678 and IMX471m, Himax HM1092 IR sensor - New codec: Milos: VPU v2.0 codec support - isp driver: gained support for Dreamchip RPPX1 ISP framework - vsp1 driver: gained support for RZ/T2H and RZ/N2H - Novalake driver: gained CVS support for new NVL hardware - dvb-core: fix feed leak on failed DMX_ADD_PID - several driver fixes, cleanups and minor improvements * tag 'media/v7.3-1' of git://git.kernel.org/pub/scm/linux/kernel/git/mchehab/linux-media: (308 commits) media: ipu-bridge: check all DMI entries when overriding sensor rotation media: v4l2-async: avoid deleting unlinked ASC entry on link error media: rzg2l-cru: Align bytesperline to hardware DMA stride requirement media: intel/ipu6: fix async notifier cleanup leak on parse error media: staging/ipu7: fix async notifier UAF on probe error path media: amd: isp4: fix self-deadlock in isp4sd_pwron_and_init() error path media: amd: isp4: release partial allocations in isp4if_alloc_fw_gpumem() media: rcar-isp: Fix VSPX reference leaks media: rcar-isp: Release ISPCORE resources media: i2c: imx415: Release runtime PM reference on VBLANK error media: i2c: imx415: Return test pattern write errors media: renesas: vsp1: Declare index variables in for loop statement media: renesas: vsp1: Make reset control optional to support platforms without a reset line media: dt-bindings: media: renesas,vsp1: Document RZ/T2H and RZ/N2H SoCs media: dt-bindings: media: renesas,fcp: Document RZ/T2H and RZ/N2H SoCs media: nxp: imx8-isi: Add additional 32-bit RGB format support media: nxp: imx8-isi: Add 16-bit raw Bayer format support media: nxp: imx8-isi: Implement per-stream reference counting for multiplexed streams media: nxp: imx8-isi: Use BIT_ULL() for 64-bit stream masks media: nxp: imx8-isi: Correct color map between V4L2 and ISI ...
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");