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/leds/trigger/ledtrig-tty.c | 357 +++++++++++++++++++++++++++++++++++++ 1 file changed, 357 insertions(+) create mode 100644 drivers/leds/trigger/ledtrig-tty.c (limited to 'drivers/leds/trigger/ledtrig-tty.c') diff --git a/drivers/leds/trigger/ledtrig-tty.c b/drivers/leds/trigger/ledtrig-tty.c new file mode 100644 index 000000000..372557114 --- /dev/null +++ b/drivers/leds/trigger/ledtrig-tty.c @@ -0,0 +1,357 @@ +// SPDX-License-Identifier: GPL-2.0 + +#include +#include +#include +#include +#include +#include +#include + +#define LEDTRIG_TTY_INTERVAL 50 + +struct ledtrig_tty_data { + struct led_classdev *led_cdev; + struct delayed_work dwork; + struct completion sysfs; + const char *ttyname; + struct tty_struct *tty; + int rx, tx; + bool mode_rx; + bool mode_tx; + bool mode_cts; + bool mode_dsr; + bool mode_dcd; + bool mode_rng; +}; + +/* Indicates which state the LED should now display */ +enum led_trigger_tty_state { + TTY_LED_BLINK, + TTY_LED_ENABLE, + TTY_LED_DISABLE, +}; + +enum led_trigger_tty_modes { + TRIGGER_TTY_RX = 0, + TRIGGER_TTY_TX, + TRIGGER_TTY_CTS, + TRIGGER_TTY_DSR, + TRIGGER_TTY_DCD, + TRIGGER_TTY_RNG, +}; + +static int ledtrig_tty_wait_for_completion(struct device *dev) +{ + struct ledtrig_tty_data *trigger_data = led_trigger_get_drvdata(dev); + int ret; + + ret = wait_for_completion_timeout(&trigger_data->sysfs, + msecs_to_jiffies(LEDTRIG_TTY_INTERVAL * 20)); + if (ret == 0) + return -ETIMEDOUT; + + return ret; +} + +static ssize_t ttyname_show(struct device *dev, + struct device_attribute *attr, char *buf) +{ + struct ledtrig_tty_data *trigger_data = led_trigger_get_drvdata(dev); + ssize_t len = 0; + int completion; + + reinit_completion(&trigger_data->sysfs); + completion = ledtrig_tty_wait_for_completion(dev); + if (completion < 0) + return completion; + + if (trigger_data->ttyname) + len = sprintf(buf, "%s\n", trigger_data->ttyname); + + return len; +} + +static ssize_t ttyname_store(struct device *dev, + struct device_attribute *attr, const char *buf, + size_t size) +{ + struct ledtrig_tty_data *trigger_data = led_trigger_get_drvdata(dev); + char *ttyname; + ssize_t ret = size; + int completion; + + if (size > 0 && buf[size - 1] == '\n') + size -= 1; + + if (size) { + ttyname = kmemdup_nul(buf, size, GFP_KERNEL); + if (!ttyname) + return -ENOMEM; + } else { + ttyname = NULL; + } + + reinit_completion(&trigger_data->sysfs); + completion = ledtrig_tty_wait_for_completion(dev); + if (completion < 0) + return completion; + + kfree(trigger_data->ttyname); + tty_kref_put(trigger_data->tty); + trigger_data->tty = NULL; + + trigger_data->ttyname = ttyname; + + return ret; +} +static DEVICE_ATTR_RW(ttyname); + +static ssize_t ledtrig_tty_attr_show(struct device *dev, char *buf, + enum led_trigger_tty_modes attr) +{ + struct ledtrig_tty_data *trigger_data = led_trigger_get_drvdata(dev); + bool state; + + switch (attr) { + case TRIGGER_TTY_RX: + state = trigger_data->mode_rx; + break; + case TRIGGER_TTY_TX: + state = trigger_data->mode_tx; + break; + case TRIGGER_TTY_CTS: + state = trigger_data->mode_cts; + break; + case TRIGGER_TTY_DSR: + state = trigger_data->mode_dsr; + break; + case TRIGGER_TTY_DCD: + state = trigger_data->mode_dcd; + break; + case TRIGGER_TTY_RNG: + state = trigger_data->mode_rng; + break; + } + + return sysfs_emit(buf, "%u\n", state); +} + +static ssize_t ledtrig_tty_attr_store(struct device *dev, const char *buf, + size_t size, enum led_trigger_tty_modes attr) +{ + struct ledtrig_tty_data *trigger_data = led_trigger_get_drvdata(dev); + bool state; + int ret; + + ret = kstrtobool(buf, &state); + if (ret) + return ret; + + switch (attr) { + case TRIGGER_TTY_RX: + trigger_data->mode_rx = state; + break; + case TRIGGER_TTY_TX: + trigger_data->mode_tx = state; + break; + case TRIGGER_TTY_CTS: + trigger_data->mode_cts = state; + break; + case TRIGGER_TTY_DSR: + trigger_data->mode_dsr = state; + break; + case TRIGGER_TTY_DCD: + trigger_data->mode_dcd = state; + break; + case TRIGGER_TTY_RNG: + trigger_data->mode_rng = state; + break; + } + + return size; +} + +#define DEFINE_TTY_TRIGGER(trigger_name, trigger) \ + static ssize_t trigger_name##_show(struct device *dev, \ + struct device_attribute *attr, char *buf) \ + { \ + return ledtrig_tty_attr_show(dev, buf, trigger); \ + } \ + static ssize_t trigger_name##_store(struct device *dev, \ + struct device_attribute *attr, const char *buf, size_t size) \ + { \ + return ledtrig_tty_attr_store(dev, buf, size, trigger); \ + } \ + static DEVICE_ATTR_RW(trigger_name) + +DEFINE_TTY_TRIGGER(rx, TRIGGER_TTY_RX); +DEFINE_TTY_TRIGGER(tx, TRIGGER_TTY_TX); +DEFINE_TTY_TRIGGER(cts, TRIGGER_TTY_CTS); +DEFINE_TTY_TRIGGER(dsr, TRIGGER_TTY_DSR); +DEFINE_TTY_TRIGGER(dcd, TRIGGER_TTY_DCD); +DEFINE_TTY_TRIGGER(rng, TRIGGER_TTY_RNG); + +static void ledtrig_tty_work(struct work_struct *work) +{ + struct ledtrig_tty_data *trigger_data = + container_of(work, struct ledtrig_tty_data, dwork.work); + enum led_trigger_tty_state state = TTY_LED_DISABLE; + unsigned long interval = LEDTRIG_TTY_INTERVAL; + bool invert = false; + int status; + int ret; + + if (!trigger_data->ttyname) + goto out; + + /* try to get the tty corresponding to $ttyname */ + if (!trigger_data->tty) { + dev_t devno; + struct tty_struct *tty; + int ret; + + ret = tty_dev_name_to_number(trigger_data->ttyname, &devno); + if (ret < 0) + /* + * A device with this name might appear later, so keep + * retrying. + */ + goto out; + + tty = tty_kopen_shared(devno); + if (IS_ERR_OR_NULL(tty)) + /* What to do? retry or abort */ + goto out; + + trigger_data->tty = tty; + } + + status = tty_get_tiocm(trigger_data->tty); + if (status > 0) { + if (trigger_data->mode_cts) { + if (status & TIOCM_CTS) + state = TTY_LED_ENABLE; + } + + if (trigger_data->mode_dsr) { + if (status & TIOCM_DSR) + state = TTY_LED_ENABLE; + } + + if (trigger_data->mode_dcd) { + if (status & TIOCM_CAR) + state = TTY_LED_ENABLE; + } + + if (trigger_data->mode_rng) { + if (status & TIOCM_RNG) + state = TTY_LED_ENABLE; + } + } + + /* + * The evaluation of rx/tx must be done after the evaluation + * of TIOCM_*, because rx/tx has priority. + */ + if (trigger_data->mode_rx || trigger_data->mode_tx) { + struct serial_icounter_struct icount; + + ret = tty_get_icount(trigger_data->tty, &icount); + if (ret) + goto out; + + if (trigger_data->mode_tx && (icount.tx != trigger_data->tx)) { + trigger_data->tx = icount.tx; + invert = state == TTY_LED_ENABLE; + state = TTY_LED_BLINK; + } + + if (trigger_data->mode_rx && (icount.rx != trigger_data->rx)) { + trigger_data->rx = icount.rx; + invert = state == TTY_LED_ENABLE; + state = TTY_LED_BLINK; + } + } + +out: + switch (state) { + case TTY_LED_BLINK: + led_blink_set_oneshot(trigger_data->led_cdev, &interval, + &interval, invert); + break; + case TTY_LED_ENABLE: + led_set_brightness(trigger_data->led_cdev, + trigger_data->led_cdev->blink_brightness); + break; + case TTY_LED_DISABLE: + fallthrough; + default: + led_set_brightness(trigger_data->led_cdev, LED_OFF); + break; + } + + complete_all(&trigger_data->sysfs); + schedule_delayed_work(&trigger_data->dwork, + msecs_to_jiffies(LEDTRIG_TTY_INTERVAL * 2)); +} + +static struct attribute *ledtrig_tty_attrs[] = { + &dev_attr_ttyname.attr, + &dev_attr_rx.attr, + &dev_attr_tx.attr, + &dev_attr_cts.attr, + &dev_attr_dsr.attr, + &dev_attr_dcd.attr, + &dev_attr_rng.attr, + NULL +}; +ATTRIBUTE_GROUPS(ledtrig_tty); + +static int ledtrig_tty_activate(struct led_classdev *led_cdev) +{ + struct ledtrig_tty_data *trigger_data; + + trigger_data = kzalloc_obj(*trigger_data); + if (!trigger_data) + return -ENOMEM; + + /* Enable default rx/tx mode */ + trigger_data->mode_rx = true; + trigger_data->mode_tx = true; + + led_set_trigger_data(led_cdev, trigger_data); + + INIT_DELAYED_WORK(&trigger_data->dwork, ledtrig_tty_work); + trigger_data->led_cdev = led_cdev; + init_completion(&trigger_data->sysfs); + + schedule_delayed_work(&trigger_data->dwork, 0); + + return 0; +} + +static void ledtrig_tty_deactivate(struct led_classdev *led_cdev) +{ + struct ledtrig_tty_data *trigger_data = led_get_trigger_data(led_cdev); + + cancel_delayed_work_sync(&trigger_data->dwork); + + kfree(trigger_data->ttyname); + tty_kref_put(trigger_data->tty); + trigger_data->tty = NULL; + + kfree(trigger_data); +} + +static struct led_trigger ledtrig_tty = { + .name = "tty", + .activate = ledtrig_tty_activate, + .deactivate = ledtrig_tty_deactivate, + .groups = ledtrig_tty_groups, +}; +module_led_trigger(ledtrig_tty); + +MODULE_AUTHOR("Uwe Kleine-König "); +MODULE_DESCRIPTION("UART LED trigger"); +MODULE_LICENSE("GPL v2"); -- cgit v1.3.1