From 4352b8aee98005853aa63f57d6377282de17a33f Mon Sep 17 00:00:00 2001 From: Linus Torvalds Date: Sun, 23 Aug 2026 13:28:57 -0700 Subject: Merge tag 'i3c/for-7.3' of git://git.kernel.org/pub/scm/linux/kernel/git/i3c/linux 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 ... --- drivers/input/input-mt.c | 534 +++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 534 insertions(+) create mode 100644 drivers/input/input-mt.c (limited to 'drivers/input/input-mt.c') diff --git a/drivers/input/input-mt.c b/drivers/input/input-mt.c new file mode 100644 index 000000000..c06e98fbd --- /dev/null +++ b/drivers/input/input-mt.c @@ -0,0 +1,534 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * Input Multitouch Library + * + * Copyright (c) 2008-2010 Henrik Rydberg + */ + +#include +#include +#include +#include "input-core-private.h" + +#define TRKID_SGN ((TRKID_MAX + 1) >> 1) + +static void copy_abs(struct input_dev *dev, unsigned int dst, unsigned int src) +{ + if (dev->absinfo && test_bit(src, dev->absbit)) { + dev->absinfo[dst] = dev->absinfo[src]; + dev->absinfo[dst].fuzz = 0; + __set_bit(dst, dev->absbit); + } +} + +/** + * input_mt_init_slots() - initialize MT input slots + * @dev: input device supporting MT events and finger tracking + * @num_slots: number of slots used by the device + * @flags: mt tasks to handle in core + * + * This function allocates all necessary memory for MT slot handling + * in the input device, prepares the ABS_MT_SLOT and + * ABS_MT_TRACKING_ID events for use and sets up appropriate buffers. + * Depending on the flags set, it also performs pointer emulation and + * frame synchronization. + * + * May be called repeatedly. Returns -EINVAL if attempting to + * reinitialize with a different number of slots. + */ +int input_mt_init_slots(struct input_dev *dev, unsigned int num_slots, + unsigned int flags) +{ + if (!num_slots) + return 0; + + if (dev->mt) + return dev->mt->num_slots != num_slots ? -EINVAL : 0; + + /* Arbitrary limit for avoiding too large memory allocation. */ + if (num_slots > 1024) + return -EINVAL; + + struct input_mt *mt __free(kfree) = + kzalloc_flex(*mt, slots, num_slots); + if (!mt) + return -ENOMEM; + + mt->num_slots = num_slots; + mt->flags = flags; + input_set_abs_params(dev, ABS_MT_SLOT, 0, num_slots - 1, 0, 0); + input_set_abs_params(dev, ABS_MT_TRACKING_ID, 0, TRKID_MAX, 0, 0); + + if (flags & (INPUT_MT_POINTER | INPUT_MT_DIRECT)) { + __set_bit(EV_KEY, dev->evbit); + __set_bit(BTN_TOUCH, dev->keybit); + + copy_abs(dev, ABS_X, ABS_MT_POSITION_X); + copy_abs(dev, ABS_Y, ABS_MT_POSITION_Y); + copy_abs(dev, ABS_PRESSURE, ABS_MT_PRESSURE); + } + if (flags & INPUT_MT_POINTER) { + __set_bit(BTN_TOOL_FINGER, dev->keybit); + __set_bit(BTN_TOOL_DOUBLETAP, dev->keybit); + if (num_slots >= 3) + __set_bit(BTN_TOOL_TRIPLETAP, dev->keybit); + if (num_slots >= 4) + __set_bit(BTN_TOOL_QUADTAP, dev->keybit); + if (num_slots >= 5) + __set_bit(BTN_TOOL_QUINTTAP, dev->keybit); + __set_bit(INPUT_PROP_POINTER, dev->propbit); + } + if (flags & INPUT_MT_DIRECT) + __set_bit(INPUT_PROP_DIRECT, dev->propbit); + if (flags & INPUT_MT_SEMI_MT) + __set_bit(INPUT_PROP_SEMI_MT, dev->propbit); + if (flags & INPUT_MT_TRACK) { + unsigned int n2 = num_slots * num_slots; + mt->red = kzalloc_objs(*mt->red, n2); + if (!mt->red) + return -ENOMEM; + } + + /* Mark slots as 'inactive' */ + for (unsigned int i = 0; i < num_slots; i++) + input_mt_set_value(&mt->slots[i], ABS_MT_TRACKING_ID, -1); + + /* Mark slots as 'unused' */ + mt->frame = 1; + + dev->mt = no_free_ptr(mt); + return 0; +} +EXPORT_SYMBOL(input_mt_init_slots); + +/** + * input_mt_destroy_slots() - frees the MT slots of the input device + * @dev: input device with allocated MT slots + * + * This function is only needed in error path as the input core will + * automatically free the MT slots when the device is destroyed. + */ +void input_mt_destroy_slots(struct input_dev *dev) +{ + if (dev->mt) { + kfree(dev->mt->red); + kfree(dev->mt); + } + dev->mt = NULL; +} +EXPORT_SYMBOL(input_mt_destroy_slots); + +/** + * input_mt_report_slot_state() - report contact state + * @dev: input device with allocated MT slots + * @tool_type: the tool type to use in this slot + * @active: true if contact is active, false otherwise + * + * Reports a contact via ABS_MT_TRACKING_ID, and optionally + * ABS_MT_TOOL_TYPE. If active is true and the slot is currently + * inactive, or if the tool type is changed, a new tracking id is + * assigned to the slot. The tool type is only reported if the + * corresponding absbit field is set. + * + * Returns true if contact is active. + */ +bool input_mt_report_slot_state(struct input_dev *dev, + unsigned int tool_type, bool active) +{ + struct input_mt *mt = dev->mt; + struct input_mt_slot *slot; + int id; + + if (!mt) + return false; + + slot = &mt->slots[mt->slot]; + slot->frame = mt->frame; + + if (!active) { + input_event(dev, EV_ABS, ABS_MT_TRACKING_ID, -1); + return false; + } + + id = input_mt_get_value(slot, ABS_MT_TRACKING_ID); + if (id < 0) + id = input_mt_new_trkid(mt); + + input_event(dev, EV_ABS, ABS_MT_TRACKING_ID, id); + input_event(dev, EV_ABS, ABS_MT_TOOL_TYPE, tool_type); + + return true; +} +EXPORT_SYMBOL(input_mt_report_slot_state); + +/** + * input_mt_report_finger_count() - report contact count + * @dev: input device with allocated MT slots + * @count: the number of contacts + * + * Reports the contact count via BTN_TOOL_FINGER, BTN_TOOL_DOUBLETAP, + * BTN_TOOL_TRIPLETAP and BTN_TOOL_QUADTAP. + * + * The input core ensures only the KEY events already setup for + * this device will produce output. + */ +void input_mt_report_finger_count(struct input_dev *dev, int count) +{ + input_event(dev, EV_KEY, BTN_TOOL_FINGER, count == 1); + input_event(dev, EV_KEY, BTN_TOOL_DOUBLETAP, count == 2); + input_event(dev, EV_KEY, BTN_TOOL_TRIPLETAP, count == 3); + input_event(dev, EV_KEY, BTN_TOOL_QUADTAP, count == 4); + input_event(dev, EV_KEY, BTN_TOOL_QUINTTAP, count == 5); +} +EXPORT_SYMBOL(input_mt_report_finger_count); + +/** + * input_mt_report_pointer_emulation() - common pointer emulation + * @dev: input device with allocated MT slots + * @use_count: report number of active contacts as finger count + * + * Performs legacy pointer emulation via BTN_TOUCH, ABS_X, ABS_Y and + * ABS_PRESSURE. Touchpad finger count is emulated if use_count is true. + * + * The input core ensures only the KEY and ABS axes already setup for + * this device will produce output. + */ +void input_mt_report_pointer_emulation(struct input_dev *dev, bool use_count) +{ + struct input_mt *mt = dev->mt; + struct input_mt_slot *oldest; + int oldid, count, i; + int p, reported_p = 0; + + if (!mt) + return; + + oldest = NULL; + oldid = mt->trkid; + count = 0; + + for (i = 0; i < mt->num_slots; ++i) { + struct input_mt_slot *ps = &mt->slots[i]; + int id = input_mt_get_value(ps, ABS_MT_TRACKING_ID); + + if (id < 0) + continue; + if ((id - oldid) & TRKID_SGN) { + oldest = ps; + oldid = id; + } + if (test_bit(ABS_MT_PRESSURE, dev->absbit)) { + p = input_mt_get_value(ps, ABS_MT_PRESSURE); + if (mt->flags & INPUT_MT_TOTAL_FORCE) + reported_p += p; + else if (oldid == id) + reported_p = p; + } + count++; + } + + input_event(dev, EV_KEY, BTN_TOUCH, count > 0); + + if (use_count) { + if (count == 0 && + !test_bit(ABS_MT_DISTANCE, dev->absbit) && + test_bit(ABS_DISTANCE, dev->absbit) && + input_abs_get_val(dev, ABS_DISTANCE) != 0) { + /* + * Force reporting BTN_TOOL_FINGER for devices that + * only report general hover (and not per-contact + * distance) when contact is in proximity but not + * on the surface. + */ + count = 1; + } + + input_mt_report_finger_count(dev, count); + } + + if (oldest) { + int x = input_mt_get_value(oldest, ABS_MT_POSITION_X); + int y = input_mt_get_value(oldest, ABS_MT_POSITION_Y); + + input_event(dev, EV_ABS, ABS_X, x); + input_event(dev, EV_ABS, ABS_Y, y); + + if (test_bit(ABS_MT_PRESSURE, dev->absbit)) + input_event(dev, EV_ABS, ABS_PRESSURE, reported_p); + } else { + if (test_bit(ABS_MT_PRESSURE, dev->absbit)) + input_event(dev, EV_ABS, ABS_PRESSURE, 0); + } +} +EXPORT_SYMBOL(input_mt_report_pointer_emulation); + +static void __input_mt_drop_unused(struct input_dev *dev, struct input_mt *mt) +{ + int i; + + lockdep_assert_held(&dev->event_lock); + + for (i = 0; i < mt->num_slots; i++) { + if (input_mt_is_active(&mt->slots[i]) && + !input_mt_is_used(mt, &mt->slots[i])) { + input_handle_event(dev, EV_ABS, ABS_MT_SLOT, i); + input_handle_event(dev, EV_ABS, ABS_MT_TRACKING_ID, -1); + } + } +} + +/** + * input_mt_drop_unused() - Inactivate slots not seen in this frame + * @dev: input device with allocated MT slots + * + * Lift all slots not seen since the last call to this function. + */ +void input_mt_drop_unused(struct input_dev *dev) +{ + struct input_mt *mt = dev->mt; + + if (mt) { + guard(spinlock_irqsave)(&dev->event_lock); + + __input_mt_drop_unused(dev, mt); + mt->frame++; + } +} +EXPORT_SYMBOL(input_mt_drop_unused); + +/** + * input_mt_release_slots() - Deactivate all slots + * @dev: input device with allocated MT slots + * + * Lift all active slots. + */ +void input_mt_release_slots(struct input_dev *dev) +{ + struct input_mt *mt = dev->mt; + + lockdep_assert_held(&dev->event_lock); + + if (mt) { + /* This will effectively mark all slots unused. */ + mt->frame++; + + __input_mt_drop_unused(dev, mt); + + if (test_bit(ABS_PRESSURE, dev->absbit)) + input_handle_event(dev, EV_ABS, ABS_PRESSURE, 0); + + mt->frame++; + } +} + +/** + * input_mt_sync_frame() - synchronize mt frame + * @dev: input device with allocated MT slots + * + * Close the frame and prepare the internal state for a new one. + * Depending on the flags, marks unused slots as inactive and performs + * pointer emulation. + */ +void input_mt_sync_frame(struct input_dev *dev) +{ + struct input_mt *mt = dev->mt; + bool use_count = false; + + if (!mt) + return; + + if (mt->flags & INPUT_MT_DROP_UNUSED) { + guard(spinlock_irqsave)(&dev->event_lock); + __input_mt_drop_unused(dev, mt); + } + + if ((mt->flags & INPUT_MT_POINTER) && !(mt->flags & INPUT_MT_SEMI_MT)) + use_count = true; + + input_mt_report_pointer_emulation(dev, use_count); + + mt->frame++; +} +EXPORT_SYMBOL(input_mt_sync_frame); + +static int adjust_dual(int *begin, int step, int *end, int eq, int mu) +{ + int f, *p, s, c; + + if (begin == end) + return 0; + + f = *begin; + p = begin + step; + s = p == end ? f + 1 : *p; + + for (; p != end; p += step) { + if (*p < f) { + s = f; + f = *p; + } else if (*p < s) { + s = *p; + } + } + + c = (f + s + 1) / 2; + if (c == 0 || (c > mu && (!eq || mu > 0))) + return 0; + /* Improve convergence for positive matrices by penalizing overcovers */ + if (s < 0 && mu <= 0) + c *= 2; + + for (p = begin; p != end; p += step) + *p -= c; + + return (c < s && s <= 0) || (f >= 0 && f < c); +} + +static void find_reduced_matrix(int *w, int nr, int nc, int nrc, int mu) +{ + int i, k, sum; + + for (k = 0; k < nrc; k++) { + for (i = 0; i < nr; i++) + adjust_dual(w + i, nr, w + i + nrc, nr <= nc, mu); + sum = 0; + for (i = 0; i < nrc; i += nr) + sum += adjust_dual(w + i, 1, w + i + nr, nc <= nr, mu); + if (!sum) + break; + } +} + +static int input_mt_set_matrix(struct input_mt *mt, + const struct input_mt_pos *pos, int num_pos, + int mu) +{ + const struct input_mt_pos *p; + struct input_mt_slot *s; + int *w = mt->red; + int x, y; + + for (s = mt->slots; s != mt->slots + mt->num_slots; s++) { + if (!input_mt_is_active(s)) + continue; + x = input_mt_get_value(s, ABS_MT_POSITION_X); + y = input_mt_get_value(s, ABS_MT_POSITION_Y); + for (p = pos; p != pos + num_pos; p++) { + int dx = x - p->x, dy = y - p->y; + *w++ = dx * dx + dy * dy - mu; + } + } + + return w - mt->red; +} + +static void input_mt_set_slots(struct input_mt *mt, + int *slots, int num_pos) +{ + struct input_mt_slot *s; + int *w = mt->red, j; + + for (j = 0; j != num_pos; j++) + slots[j] = -1; + + for (s = mt->slots; s != mt->slots + mt->num_slots; s++) { + if (!input_mt_is_active(s)) + continue; + + for (j = 0; j != num_pos; j++) { + if (w[j] < 0) { + slots[j] = s - mt->slots; + break; + } + } + + w += num_pos; + } + + for (s = mt->slots; s != mt->slots + mt->num_slots; s++) { + if (input_mt_is_active(s)) + continue; + + for (j = 0; j != num_pos; j++) { + if (slots[j] < 0) { + slots[j] = s - mt->slots; + break; + } + } + } +} + +/** + * input_mt_assign_slots() - perform a best-match assignment + * @dev: input device with allocated MT slots + * @slots: the slot assignment to be filled + * @pos: the position array to match + * @num_pos: number of positions + * @dmax: maximum ABS_MT_POSITION displacement (zero for infinite) + * + * Performs a best match against the current contacts and returns + * the slot assignment list. New contacts are assigned to unused + * slots. + * + * The assignments are balanced so that all coordinate displacements are + * below the euclidian distance dmax. If no such assignment can be found, + * some contacts are assigned to unused slots. + * + * Returns zero on success, or negative error in case of failure. + */ +int input_mt_assign_slots(struct input_dev *dev, int *slots, + const struct input_mt_pos *pos, int num_pos, + int dmax) +{ + struct input_mt *mt = dev->mt; + int mu = 2 * dmax * dmax; + int nrc; + + if (!mt || !mt->red) + return -ENXIO; + if (num_pos > mt->num_slots) + return -EINVAL; + if (num_pos < 1) + return 0; + + nrc = input_mt_set_matrix(mt, pos, num_pos, mu); + find_reduced_matrix(mt->red, num_pos, nrc / num_pos, nrc, mu); + input_mt_set_slots(mt, slots, num_pos); + + return 0; +} +EXPORT_SYMBOL(input_mt_assign_slots); + +/** + * input_mt_get_slot_by_key() - return slot matching key + * @dev: input device with allocated MT slots + * @key: the key of the sought slot + * + * Returns the slot of the given key, if it exists, otherwise + * set the key on the first unused slot and return. + * + * If no available slot can be found, -1 is returned. + * Note that for this function to work properly, input_mt_sync_frame() has + * to be called at each frame. + */ +int input_mt_get_slot_by_key(struct input_dev *dev, int key) +{ + struct input_mt *mt = dev->mt; + struct input_mt_slot *s; + + if (!mt) + return -1; + + for (s = mt->slots; s != mt->slots + mt->num_slots; s++) + if (input_mt_is_active(s) && s->key == key) + return s - mt->slots; + + for (s = mt->slots; s != mt->slots + mt->num_slots; s++) + if (!input_mt_is_active(s) && !input_mt_is_used(mt, s)) { + s->key = key; + return s - mt->slots; + } + + return -1; +} +EXPORT_SYMBOL(input_mt_get_slot_by_key); -- cgit v1.3.1