From 034dd340b08be1f2f0477ad16131d609f9dbd53c Mon Sep 17 00:00:00 2001 From: Linus Torvalds Date: Sun, 30 Aug 2026 09:22:00 -0700 Subject: Merge tag 'trace-v7.3-2' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace Pull tracing fixes from Steven Rostedt: - Fix error output of boot instance creation failure Currently if a boot instance creation fails, instead of printing out the name of the instance that failed, it prints "(null)". That is because it prints "cur_str" that had already been processed by strsep(). Print the saved name instead. While at it, print the error code of the failure. - Fix use-after-free for same named historgrams Histograms can be named so that they can be used in multiple events. But if the named histogram has a variable attached, the second event that uses the named histogram which duplicates it and needs to free the original after duplication leaves the old variable in place and still visible. If another histogram uses than variable, it will use the stale one which will try to reference the freed duplicate histogram and crash the kernel. Free the duplicate variables along with the duplicated histogram data. - Check return value of kthread_run() in event self test The events self tests uses a kthread for testing but does not check if it succeeded in creating a kthread. If the kthread creation were to fail, the code will still try to call kthread_stop() on the error returned. - Fix race between reading trace_pipe and updating subbuffer size If a user is reading the trace_pipe file at the same time they update the ring buffer sub-buffer size, can cause the trace_pipe read to read stale data. Add trace_access_lock() around updating the ring buffer sub-buffer size. - Fix eventfs_inode on failure path in creation of the events directory In the creation of the "events" directory, if after allocating the eventfs_inode a failure is detected, it calls cleanup_ei() which calls free_ei(). The free_ei() will test if eventfs_inode being freed has no children. It is a bug if it does. But on the failure case of the creation of the "events" directory, the children lists have not yet been initialized and the free will trigger a warning because list_empty() on an uninitialized list returns false. Move the initialization into init_ei() where it makes more sense and makes sure that a created eventfs_inode has its lists initialized upon creation. - Check return value of kthread_run() in ftrace direct sample code The sample code that shows how to use the ftrace direct calls does not test the return of kthread_run() to see if it succeeds. Return a failure if the kthread_run() doesn't succeed. - Clear user events state on fork in case of alloc failure On fork, the child gets a pointer to the parent's user events state. It makes a copy of it then updates the child's pointer to it. But if the allocation fails, the duplication function leaves the child with a pointer to its parent's descriptor. When the child cleans up its data, it will free the parent's descriptor while the parent is still using it. In the duplication function, set the child's user_event_mm to NULL before testing if the allocation succeeded, and when it exits it will not free the parent's descriptor. - Fix retry exhaustion in simple ring buffer reader swap simple_ring_buffer_swap_reader_page() starts with retry set to 8 and post-decrements it only after a failed link replacement. On the final attempt, a successful replacement leaves retry at zero, while a failed replacement leaves it at -1. But the check for success expects the retry value to be non-zero and exits with an error on zero. This is the opposite result. Fix it. - Fail nicely when the remote swap_reader_page() returns an error Currently, if the swap_reader_page() of a remote buffer fails, it triggers a WARN_ON_ONCE() and continues normally. Instead, have it exit with an error and a pr_warn() print instead of a full WARNING. * tag 'trace-v7.3-2' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace: ring-buffer: Stop remote reader update when page swap fails tracing: Fix retry exhaustion in simple ring buffer reader swap tracing/user_events: Clear copied tracing state before fork duplication samples/ftrace: Fix kthread_stop() on ERR_PTR in ftrace-direct-multi-modify samples/ftrace: Fix kthread_stop() on ERR_PTR in ftrace-direct-modify eventfs: Initialize ei->children and ei->list in init_ei() tracing: Fix use-after-free in trace_pipe read on sub-buffer order change tracing: Fix crash passing ERR_PTR to kthread_stop() tracing: Fix use-after-free with same-name named triggers tracing: Fix logged instance name on creation failure --- drivers/input/touchscreen/ektf2127.c | 381 +++++++++++++++++++++++++++++++++++ 1 file changed, 381 insertions(+) create mode 100644 drivers/input/touchscreen/ektf2127.c (limited to 'drivers/input/touchscreen/ektf2127.c') diff --git a/drivers/input/touchscreen/ektf2127.c b/drivers/input/touchscreen/ektf2127.c new file mode 100644 index 000000000..572a37d4e --- /dev/null +++ b/drivers/input/touchscreen/ektf2127.c @@ -0,0 +1,381 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * Driver for ELAN eKTF2127 i2c touchscreen controller + * + * For this driver the layout of the Chipone icn8318 i2c + * touchscreencontroller is used. + * + * Author: + * Michel Verlaan + * Siebren Vroegindeweij + * + * Original chipone_icn8318 driver: + * Hans de Goede + */ + +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include + +/* Packet header defines (first byte of data send / received) */ +#define EKTF2127_NOISE 0x40 +#define EKTF2127_RESPONSE 0x52 +#define EKTF2127_REQUEST 0x53 +#define EKTF2127_HELLO 0x55 +#define EKTF2127_REPORT2 0x5a +#define EKTF2127_REPORT 0x5d +#define EKTF2127_CALIB_DONE 0x66 + +/* Register defines (second byte of data send / received) */ +#define EKTF2127_ENV_NOISY 0x41 +#define EKTF2127_HEIGHT 0x60 +#define EKTF2127_WIDTH 0x63 + +/* 2 bytes header + 5 * 3 bytes coordinates + 3 bytes pressure info + footer */ +#define EKTF2127_TOUCH_REPORT_SIZE 21 +#define EKTF2127_MAX_TOUCHES 5 + +struct ektf2127_ts { + struct i2c_client *client; + struct input_dev *input; + struct gpio_desc *power_gpios; + struct touchscreen_properties prop; + int status_shift; +}; + +struct ektf2127_i2c_chip_data { + int status_shift; +}; + +static void ektf2127_parse_coordinates(const u8 *buf, unsigned int touch_count, + struct input_mt_pos *touches) +{ + int index = 0; + int i; + + for (i = 0; i < touch_count; i++) { + index = 2 + i * 3; + + touches[i].x = (buf[index] & 0x0f); + touches[i].x <<= 8; + touches[i].x |= buf[index + 2]; + + touches[i].y = (buf[index] & 0xf0); + touches[i].y <<= 4; + touches[i].y |= buf[index + 1]; + } +} + +static void ektf2127_report_event(struct ektf2127_ts *ts, const u8 *buf) +{ + struct input_mt_pos touches[EKTF2127_MAX_TOUCHES]; + int slots[EKTF2127_MAX_TOUCHES]; + unsigned int touch_count, i; + + touch_count = buf[1] & 0x07; + if (touch_count > EKTF2127_MAX_TOUCHES) { + dev_err(&ts->client->dev, + "Too many touches %d > %d\n", + touch_count, EKTF2127_MAX_TOUCHES); + touch_count = EKTF2127_MAX_TOUCHES; + } + + ektf2127_parse_coordinates(buf, touch_count, touches); + input_mt_assign_slots(ts->input, slots, touches, + touch_count, 0); + + for (i = 0; i < touch_count; i++) { + input_mt_slot(ts->input, slots[i]); + input_mt_report_slot_state(ts->input, MT_TOOL_FINGER, true); + touchscreen_report_pos(ts->input, &ts->prop, + touches[i].x, touches[i].y, true); + } + + input_mt_sync_frame(ts->input); + input_sync(ts->input); +} + +static void ektf2127_report2_contact(struct ektf2127_ts *ts, int slot, + const u8 *buf, bool active) +{ + input_mt_slot(ts->input, slot); + input_mt_report_slot_state(ts->input, MT_TOOL_FINGER, active); + + if (active) { + int x = (buf[0] & 0xf0) << 4 | buf[1]; + int y = (buf[0] & 0x0f) << 8 | buf[2]; + + touchscreen_report_pos(ts->input, &ts->prop, x, y, true); + } +} + +static void ektf2127_report2_event(struct ektf2127_ts *ts, const u8 *buf) +{ + ektf2127_report2_contact(ts, 0, &buf[1], !!(buf[7] & BIT(ts->status_shift))); + ektf2127_report2_contact(ts, 1, &buf[4], !!(buf[7] & BIT(ts->status_shift + 1))); + + input_mt_sync_frame(ts->input); + input_sync(ts->input); +} + +static irqreturn_t ektf2127_irq(int irq, void *dev_id) +{ + struct ektf2127_ts *ts = dev_id; + struct device *dev = &ts->client->dev; + char buf[EKTF2127_TOUCH_REPORT_SIZE]; + int ret; + + ret = i2c_master_recv(ts->client, buf, EKTF2127_TOUCH_REPORT_SIZE); + if (ret != EKTF2127_TOUCH_REPORT_SIZE) { + dev_err(dev, "Error reading touch data: %d\n", ret); + goto out; + } + + switch (buf[0]) { + case EKTF2127_REPORT: + ektf2127_report_event(ts, buf); + break; + + case EKTF2127_REPORT2: + ektf2127_report2_event(ts, buf); + break; + + case EKTF2127_NOISE: + if (buf[1] == EKTF2127_ENV_NOISY) + dev_dbg(dev, "Environment is electrically noisy\n"); + break; + + case EKTF2127_HELLO: + case EKTF2127_CALIB_DONE: + break; + + default: + dev_err(dev, "Unexpected packet header byte %#02x\n", buf[0]); + break; + } + +out: + return IRQ_HANDLED; +} + +static int ektf2127_start(struct input_dev *dev) +{ + struct ektf2127_ts *ts = input_get_drvdata(dev); + + enable_irq(ts->client->irq); + gpiod_set_value_cansleep(ts->power_gpios, 1); + + return 0; +} + +static void ektf2127_stop(struct input_dev *dev) +{ + struct ektf2127_ts *ts = input_get_drvdata(dev); + + disable_irq(ts->client->irq); + gpiod_set_value_cansleep(ts->power_gpios, 0); +} + +static int ektf2127_suspend(struct device *dev) +{ + struct ektf2127_ts *ts = i2c_get_clientdata(to_i2c_client(dev)); + + guard(mutex)(&ts->input->mutex); + + if (input_device_enabled(ts->input)) + ektf2127_stop(ts->input); + + return 0; +} + +static int ektf2127_resume(struct device *dev) +{ + struct ektf2127_ts *ts = i2c_get_clientdata(to_i2c_client(dev)); + + guard(mutex)(&ts->input->mutex); + + if (input_device_enabled(ts->input)) + ektf2127_start(ts->input); + + return 0; +} + +static DEFINE_SIMPLE_DEV_PM_OPS(ektf2127_pm_ops, ektf2127_suspend, + ektf2127_resume); + +static int ektf2127_query_dimension(struct i2c_client *client, bool width) +{ + struct device *dev = &client->dev; + const char *what = width ? "width" : "height"; + u8 what_code = width ? EKTF2127_WIDTH : EKTF2127_HEIGHT; + u8 buf[4]; + int ret; + int error; + + /* Request dimension */ + buf[0] = EKTF2127_REQUEST; + buf[1] = width ? EKTF2127_WIDTH : EKTF2127_HEIGHT; + buf[2] = 0x00; + buf[3] = 0x00; + ret = i2c_master_send(client, buf, sizeof(buf)); + if (ret != sizeof(buf)) { + error = ret < 0 ? ret : -EIO; + dev_err(dev, "Failed to request %s: %d\n", what, error); + return error; + } + + msleep(20); + + /* Read response */ + ret = i2c_master_recv(client, buf, sizeof(buf)); + if (ret != sizeof(buf)) { + error = ret < 0 ? ret : -EIO; + dev_err(dev, "Failed to receive %s data: %d\n", what, error); + return error; + } + + if (buf[0] != EKTF2127_RESPONSE || buf[1] != what_code) { + dev_err(dev, "Unexpected %s data: %#02x %#02x\n", + what, buf[0], buf[1]); + return -EIO; + } + + return (((buf[3] & 0xf0) << 4) | buf[2]) - 1; +} + +static int ektf2127_probe(struct i2c_client *client) +{ + struct device *dev = &client->dev; + const struct ektf2127_i2c_chip_data *chip_data; + struct ektf2127_ts *ts; + struct input_dev *input; + u8 buf[4]; + int max_x, max_y; + int error; + + if (!client->irq) { + dev_err(dev, "Error no irq specified\n"); + return -EINVAL; + } + + ts = devm_kzalloc(dev, sizeof(*ts), GFP_KERNEL); + if (!ts) + return -ENOMEM; + + /* This requests the gpio *and* turns on the touchscreen controller */ + ts->power_gpios = devm_gpiod_get(dev, "power", GPIOD_OUT_HIGH); + if (IS_ERR(ts->power_gpios)) + return dev_err_probe(dev, PTR_ERR(ts->power_gpios), "Error getting power gpio\n"); + + input = devm_input_allocate_device(dev); + if (!input) + return -ENOMEM; + + input->name = client->name; + input->id.bustype = BUS_I2C; + input->open = ektf2127_start; + input->close = ektf2127_stop; + + ts->client = client; + + /* Read hello (ignore result, depends on initial power state) */ + msleep(20); + i2c_master_recv(ts->client, buf, sizeof(buf)); + + /* Read resolution from chip */ + max_x = ektf2127_query_dimension(client, true); + if (max_x < 0) + return max_x; + + max_y = ektf2127_query_dimension(client, false); + if (max_y < 0) + return max_y; + + input_set_abs_params(input, ABS_MT_POSITION_X, 0, max_x, 0, 0); + input_set_abs_params(input, ABS_MT_POSITION_Y, 0, max_y, 0, 0); + touchscreen_parse_properties(input, true, &ts->prop); + + error = input_mt_init_slots(input, EKTF2127_MAX_TOUCHES, + INPUT_MT_DIRECT | + INPUT_MT_DROP_UNUSED | + INPUT_MT_TRACK); + if (error) + return error; + + ts->input = input; + + chip_data = i2c_get_match_data(client); + if (!chip_data) + return dev_err_probe(&client->dev, -EINVAL, "missing chip data\n"); + + ts->status_shift = chip_data->status_shift; + + input_set_drvdata(input, ts); + + error = devm_request_threaded_irq(dev, client->irq, + NULL, ektf2127_irq, + IRQF_ONESHOT, client->name, ts); + if (error) { + dev_err(dev, "Error requesting irq: %d\n", error); + return error; + } + + /* Stop device till opened */ + ektf2127_stop(ts->input); + + error = input_register_device(input); + if (error) + return error; + + i2c_set_clientdata(client, ts); + + return 0; +} + +static const struct ektf2127_i2c_chip_data ektf2127_data = { + .status_shift = 1, +}; + +static const struct ektf2127_i2c_chip_data ektf2232_data = { + .status_shift = 0, +}; + +#ifdef CONFIG_OF +static const struct of_device_id ektf2127_of_match[] = { + { .compatible = "elan,ektf2127", .data = &ektf2127_data}, + { .compatible = "elan,ektf2132", .data = &ektf2127_data}, + { .compatible = "elan,ektf2232", .data = &ektf2232_data}, + {} +}; +MODULE_DEVICE_TABLE(of, ektf2127_of_match); +#endif + +static const struct i2c_device_id ektf2127_i2c_id[] = { + { .name = "ektf2127", .driver_data = (long)&ektf2127_data }, + { .name = "ektf2132", .driver_data = (long)&ektf2127_data }, + { .name = "ektf2232", .driver_data = (long)&ektf2232_data }, + {} +}; +MODULE_DEVICE_TABLE(i2c, ektf2127_i2c_id); + +static struct i2c_driver ektf2127_driver = { + .driver = { + .name = "elan_ektf2127", + .pm = pm_sleep_ptr(&ektf2127_pm_ops), + .of_match_table = of_match_ptr(ektf2127_of_match), + }, + .probe = ektf2127_probe, + .id_table = ektf2127_i2c_id, +}; +module_i2c_driver(ektf2127_driver); + +MODULE_DESCRIPTION("ELAN eKTF2127/eKTF2132 I2C Touchscreen Driver"); +MODULE_AUTHOR("Michel Verlaan, Siebren Vroegindeweij"); +MODULE_LICENSE("GPL"); -- cgit v1.3.1