Until now, the LED blinks when data is sent via the tty (rx/tx).
This is not configurable.
This change adds the possibility to make the indication for the direction
of the transmitted data independently controllable via the new rx and
tx sysfs entries.
- rx:
Signal reception (rx) of data on the named tty device.
If set to 0, the LED will not blink on reception.
If set to 1 (default), the LED will blink on reception.
- tx:
Signal transmission (tx) of data on the named tty device.
If set to 0, the LED will not blink on transmission.
If set to 1 (default), the LED will blink on transmission.
This new sysfs entry are on by default. Thus the trigger behaves as
before this change.
Signed-off-by: Florian Eckert <fe@xxxxxxxxxx>
---
.../ABI/testing/sysfs-class-led-trigger-tty | 16 +++
drivers/leds/trigger/ledtrig-tty.c | 124 ++++++++++++++++--
2 files changed, 130 insertions(+), 10 deletions(-)
diff --git a/Documentation/ABI/testing/sysfs-class-led-trigger-tty b/Documentation/ABI/testing/sysfs-class-led-trigger-tty
index 2bf6b24e781b..504dece151b8 100644
--- a/Documentation/ABI/testing/sysfs-class-led-trigger-tty
+++ b/Documentation/ABI/testing/sysfs-class-led-trigger-tty
@@ -4,3 +4,19 @@ KernelVersion: 5.10
Contact: linux-leds@xxxxxxxxxxxxxxx
Description:
Specifies the tty device name of the triggering tty
+
+What: /sys/class/leds/<led>/rx
+Date: February 2024
+KernelVersion: 6.8
+Description:
+ Signal reception (rx) of data on the named tty device.
+ If set to 0, the LED will not blink on reception.
+ If set to 1 (default), the LED will blink on reception.
+
+What: /sys/class/leds/<led>/tx
+Date: February 2024
+KernelVersion: 6.8
+Description:
+ Signal transmission (tx) of data on the named tty device.
+ If set to 0, the LED will not blink on transmission.
+ If set to 1 (default), the LED will blink on transmission.
diff --git a/drivers/leds/trigger/ledtrig-tty.c b/drivers/leds/trigger/ledtrig-tty.c
index 3badf74fa420..1a40a78bf1ee 100644
--- a/drivers/leds/trigger/ledtrig-tty.c
+++ b/drivers/leds/trigger/ledtrig-tty.c
@@ -17,6 +17,19 @@ struct ledtrig_tty_data {
const char *ttyname;
struct tty_struct *tty;
int rx, tx;
+ bool mode_rx;
+ bool mode_tx;
+};
+
+/* Indicates which state the LED should now display */
+enum led_trigger_tty_state {
+ TTY_LED_BLINK,
+ TTY_LED_DISABLE,
+};
+
+enum led_trigger_tty_modes {
+ TRIGGER_TTY_RX = 0,
+ TRIGGER_TTY_TX,
};
static int ledtrig_tty_waitforcompletion(struct device *dev)
@@ -86,12 +99,82 @@ static ssize_t ttyname_store(struct device *dev,
}
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);
+ int completion;
+ bool state;
+
+ reinit_completion(&trigger_data->sysfs);
+ completion = ledtrig_tty_waitforcompletion(dev);
+ if (completion < 0)
+ return completion;
+
+ switch (attr) {
+ case TRIGGER_TTY_RX:
+ state = trigger_data->mode_rx;
+ break;
+ case TRIGGER_TTY_TX:
+ state = trigger_data->mode_tx;
+ 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);
+ int completion;
+ bool state;
+ int ret;
+
+ ret = kstrtobool(buf, &state);
+ if (ret)
+ return ret;
+
+ reinit_completion(&trigger_data->sysfs);
+ completion = ledtrig_tty_waitforcompletion(dev);
+ if (completion < 0)
+ return completion;
+
+ switch (attr) {
+ case TRIGGER_TTY_RX:
+ trigger_data->mode_rx = state;
+ break;
+ case TRIGGER_TTY_TX:
+ trigger_data->mode_tx = 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);
+
static void ledtrig_tty_work(struct work_struct *work)
{
struct ledtrig_tty_data *trigger_data =
container_of(work, struct ledtrig_tty_data, dwork.work);
- struct serial_icounter_struct icount;
struct led_classdev *led_cdev = trigger_data->led_cdev;
+ enum led_trigger_tty_state state = TTY_LED_DISABLE;
+ unsigned long interval = LEDTRIG_TTY_INTERVAL;
int ret;
if (!trigger_data->ttyname)
@@ -119,21 +202,36 @@ static void ledtrig_tty_work(struct work_struct *work)
trigger_data->tty = tty;
}
- ret = tty_get_icount(trigger_data->tty, &icount);
- if (ret)
- goto out;
+ if (trigger_data->mode_rx || trigger_data->mode_tx) {
+ struct serial_icounter_struct icount;
- if (icount.rx != trigger_data->rx ||
- icount.tx != trigger_data->tx) {
- unsigned long interval = LEDTRIG_TTY_INTERVAL;
+ ret = tty_get_icount(trigger_data->tty, &icount);
+ if (ret)
+ goto out;
- led_blink_set_oneshot(led_cdev, &interval, &interval, 0);
+ if (trigger_data->mode_tx && (icount.tx != trigger_data->tx)) {
+ trigger_data->tx = icount.tx;
+ state = TTY_LED_BLINK;
+ }
- trigger_data->rx = icount.rx;
- trigger_data->tx = icount.tx;
+ if (trigger_data->mode_rx && (icount.rx != trigger_data->rx)) {
+ trigger_data->rx = icount.rx;
+ state = TTY_LED_BLINK;
+ }
}
out:
+ switch (state) {
+ case TTY_LED_BLINK:
+ led_blink_set_oneshot(led_cdev, &interval, &interval, 0);
+ break;
+ case TTY_LED_DISABLE:
+ fallthrough;
+ default:
+ led_set_brightness(led_cdev, LED_OFF);
+ break;
+ }
+
complete_all(&trigger_data->sysfs);
schedule_delayed_work(&trigger_data->dwork,
msecs_to_jiffies(LEDTRIG_TTY_INTERVAL * 2));
@@ -141,6 +239,8 @@ static void ledtrig_tty_work(struct work_struct *work)
static struct attribute *ledtrig_tty_attrs[] = {
&dev_attr_ttyname.attr,
+ &dev_attr_rx.attr,
+ &dev_attr_tx.attr,
NULL
};
ATTRIBUTE_GROUPS(ledtrig_tty);
@@ -153,6 +253,10 @@ static int ledtrig_tty_activate(struct led_classdev *led_cdev)
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);
--
2.30.2
