From 9cc63f8bcd560c760d0b12e15bba8f81c86237cf Mon Sep 17 00:00:00 2001 From: "Paul E. McKenney" Date: Fri, 14 Aug 2026 15:43:51 -0700 Subject: 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 HEAD 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. --- drivers/input/touchscreen/touchwin.c | 184 +++++++++++++++++++++++++++++++++++ 1 file changed, 184 insertions(+) create mode 100644 drivers/input/touchscreen/touchwin.c (limited to 'drivers/input/touchscreen/touchwin.c') diff --git a/drivers/input/touchscreen/touchwin.c b/drivers/input/touchscreen/touchwin.c new file mode 100644 index 000000000..3ed33378d --- /dev/null +++ b/drivers/input/touchscreen/touchwin.c @@ -0,0 +1,184 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * Touchwindow serial touchscreen driver + * + * Copyright (c) 2006 Rick Koch + * + * Based on MicroTouch driver (drivers/input/touchscreen/mtouch.c) + * Copyright (c) 2004 Vojtech Pavlik + * and Dan Streetman + */ + + +/* + * 2005/02/19 Rick Koch: + * The Touchwindow I used is made by Edmark Corp. and + * constantly outputs a stream of 0's unless it is touched. + * It then outputs 3 bytes: X, Y, and a copy of Y. + */ + +#include +#include +#include +#include +#include +#include + +#define DRIVER_DESC "Touchwindow serial touchscreen driver" + +MODULE_AUTHOR("Rick Koch "); +MODULE_DESCRIPTION(DRIVER_DESC); +MODULE_LICENSE("GPL"); + +/* + * Definitions & global arrays. + */ + +#define TW_LENGTH 3 + +#define TW_MIN_XC 0 +#define TW_MAX_XC 0xff +#define TW_MIN_YC 0 +#define TW_MAX_YC 0xff + +/* + * Per-touchscreen data. + */ + +struct tw { + struct input_dev *dev; + struct serio *serio; + int idx; + int touched; + unsigned char data[TW_LENGTH]; + char phys[32]; +}; + +static irqreturn_t tw_interrupt(struct serio *serio, + unsigned char data, unsigned int flags) +{ + struct tw *tw = serio_get_drvdata(serio); + struct input_dev *dev = tw->dev; + + if (data) { /* touch */ + tw->touched = 1; + tw->data[tw->idx++] = data; + /* a full packet ends the accumulation, valid or not */ + if (tw->idx == TW_LENGTH) { + /* report only if the two Y's are the same */ + if (tw->data[1] == tw->data[2]) { + input_report_abs(dev, ABS_X, tw->data[0]); + input_report_abs(dev, ABS_Y, tw->data[1]); + input_report_key(dev, BTN_TOUCH, 1); + input_sync(dev); + } + tw->idx = 0; + } + } else if (tw->touched) { /* untouch */ + input_report_key(dev, BTN_TOUCH, 0); + input_sync(dev); + tw->idx = 0; + tw->touched = 0; + } + + return IRQ_HANDLED; +} + +/* + * tw_disconnect() is the opposite of tw_connect() + */ + +static void tw_disconnect(struct serio *serio) +{ + struct tw *tw = serio_get_drvdata(serio); + + input_get_device(tw->dev); + input_unregister_device(tw->dev); + serio_close(serio); + serio_set_drvdata(serio, NULL); + input_put_device(tw->dev); + kfree(tw); +} + +/* + * tw_connect() is the routine that is called when someone adds a + * new serio device that supports the Touchwin protocol and registers it as + * an input device. + */ + +static int tw_connect(struct serio *serio, struct serio_driver *drv) +{ + struct tw *tw; + struct input_dev *input_dev; + int err; + + tw = kzalloc_obj(*tw); + input_dev = input_allocate_device(); + if (!tw || !input_dev) { + err = -ENOMEM; + goto fail1; + } + + tw->serio = serio; + tw->dev = input_dev; + scnprintf(tw->phys, sizeof(tw->phys), "%s/input0", serio->phys); + + input_dev->name = "Touchwindow Serial TouchScreen"; + input_dev->phys = tw->phys; + input_dev->id.bustype = BUS_RS232; + input_dev->id.vendor = SERIO_TOUCHWIN; + input_dev->id.product = 0; + input_dev->id.version = 0x0100; + input_dev->dev.parent = &serio->dev; + input_dev->evbit[0] = BIT_MASK(EV_KEY) | BIT_MASK(EV_ABS); + input_dev->keybit[BIT_WORD(BTN_TOUCH)] = BIT_MASK(BTN_TOUCH); + input_set_abs_params(tw->dev, ABS_X, TW_MIN_XC, TW_MAX_XC, 0, 0); + input_set_abs_params(tw->dev, ABS_Y, TW_MIN_YC, TW_MAX_YC, 0, 0); + + serio_set_drvdata(serio, tw); + + err = serio_open(serio, drv); + if (err) + goto fail2; + + err = input_register_device(tw->dev); + if (err) + goto fail3; + + return 0; + + fail3: serio_close(serio); + fail2: serio_set_drvdata(serio, NULL); + fail1: input_free_device(input_dev); + kfree(tw); + return err; +} + +/* + * The serio driver structure. + */ + +static const struct serio_device_id tw_serio_ids[] = { + { + .type = SERIO_RS232, + .proto = SERIO_TOUCHWIN, + .id = SERIO_ANY, + .extra = SERIO_ANY, + }, + { 0 } +}; + +MODULE_DEVICE_TABLE(serio, tw_serio_ids); + +static struct serio_driver tw_drv = { + .driver = { + .name = "touchwin", + }, + .description = DRIVER_DESC, + .id_table = tw_serio_ids, + .interrupt = tw_interrupt, + .connect = tw_connect, + .disconnect = tw_disconnect, +}; + +module_serio_driver(tw_drv); -- cgit v1.3.1