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authorDanilo Krummrich <dakr@kernel.org>2026-08-13 18:52:04 +0200
committerDanilo Krummrich <dakr@kernel.org>2026-08-17 01:41:36 +0200
commitf146c7bc85a51f95c05e0f8173d484eb301ece78 (patch)
tree07296ae54ed6551492b0c609dc0f5463f61f89ca /drivers/input/touchscreen.c
downloadlinux-stable-f146c7bc85a51f95c05e0f8173d484eb301ece78.tar.gz
linux-stable-f146c7bc85a51f95c05e0f8173d484eb301ece78.zip
PCI: Add pci_irq_type() to query the allocated interrupt typegrafted
Add a helper that returns PCI_IRQ_MSIX, PCI_IRQ_MSI, or PCI_IRQ_INTX based on the interrupt type the PCI core selected after pci_alloc_irq_vectors(). Several drivers already open-code this check against pdev->msix_enabled and pdev->msi_enabled, or even open code this helper [1]. A common helper avoids the duplication and keeps drivers from accessing the bitfield directly (see also [2]). Acked-by: Bjorn Helgaas <bhelgaas@google.com> Tested-by: John Hubbard <jhubbard@nvidia.com> Link: https://elixir.bootlin.com/linux/v7.1/source/drivers/net/ethernet/aquantia/atlantic/aq_pci_func.c#L196 [1] Inspired-by: John Hubbard <jhubbard@nvidia.com> Link: https://lore.kernel.org/all/DKKG2QM3YJYB.Z2H2B2UXJ75N@kernel.org/ [2] Reviewed-by: Gary Guo <gary@garyguo.net> Link: https://patch.msgid.link/20260813165234.620555-5-dakr@kernel.org [ Add missing pci_irq_type() stub for CONFIG_PCI=n. ] Signed-off-by: Danilo Krummrich <dakr@kernel.org>
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");