Changes in v9:
==============
- As requested, I have removed the memory leak fix patch from the previous
patch series v8 and have send this patch directly to the stable
mailinglist [10].
- I also have removed the not needed wait for completion code path on
sysfs attr store and show, for the new configuration options, as
requested by greg k-h [11].
- Patch v8 3/6 dropped, because the change is not correct as mentiond
by greg k-h [12] and this part of the code will be removed anyway
in this patch series.
- Update naming of the function ledtrig_tty_waitforcompletion() to
ledtrig_tty_wait_for_completion() which match better with the API call
function wait_for_completion_timeout().
Thanks to all reviewers for the suggestions for improvement :+1: of this
patch set.
Links:
[10] https://lore.kernel.org/stable/2023112718-profane-dipped-a9a8@gregkh/T/#m6b36fde65a0ddacbe1fc94a14778a304775b2e79
[11] https://lore.kernel.org/linux-leds/2023112334-unquote-robust-15b8@gregkh/
[12] https://lore.kernel.org/linux-leds/2023112300-registrar-preface-2225@gregkh/
Changes in v8:
==============
v8: https://lore.kernel.org/linux-leds/[email protected]/
- As requested by greg k-h [6], I have send the patch 2/7 of this series
about the memory leak also to stable.vger.kernel.org [7]. This has
already received a 'Reviewed-by' from Uwe [8].
- As requested by Maarten, I have adopted his suggestion to invert the LED
blink, so that I do not have to save the 'state' in the tty data
struct [9].
Links:
[6] https://lore.kernel.org/linux-leds/[email protected]/T/#me43be56f4063082e7b47858773ea8067a3846466
[7] https://lore.kernel.org/stable/[email protected]/T/#t
[8] https://lore.kernel.org/stable/[email protected]/T/#m78a946889e4722903b2a79e3a465d8da0ca16333
[9] https://lore.kernel.org/linux-leds/[email protected]/T/#m43df92b665f613fe0af7d5d003a3804404f1c494
Changes in v7:
==============
v7: https://lore.kernel.org/linux-leds/[email protected]/
- Patch 1/7 is no longer included from the previous patch set v6, as it has
already been merged into the master branch [5].
- As requested by Maarten, I have added a 'Fixes:' tag to patch 2/6 of
this patch set, so that this commit should also be backported to the
stable branches, as it is a memory leak.
- As requested by Maarten, I added an invert flag on LED blink, so that
the LED blinks in the correct order.
* LED was 'on' in the previous round, then it should first go 'off' and
then 'on' again when it should blink (data has been transferred).
* LED was 'off' in the previous round, then it should first go 'on' and
then 'off' again when it should blink (data has been transferred).
Links:
[5] https://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git/commit/drivers/tty/tty_io.c?h=next-20231106&id=838eb763c3e939a8de8d4c55a17ddcce737685c1
Changes in v6:
==============
v6: https://lore.kernel.org/linux-leds/[email protected]/
This is a paritial rewrite of the changes to make the function for
setting the tty evaluation configurable. This change was requested and
comment by Greg K-H at the last review [1]. The main changes are.
- Split the changes into smaller commits to make reviewing easier.
- Use a completion to sync the sysfs and the delay scheduler work on
shared variables.
- Adding the base-commit to this overview, that reviewer know which base
commit I am using.
Base branch is:
https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
Patch [1/7]:
This patch is already included in the tty branch [2], but it is still
included in this patchsset, so that the following patches of the
base-commit branch could be applied correctly.
Patch [2/7]:
Add a new helper function tty_get_tiocm(). This got already a
'Acked-by: Greg Kroah-Hartman' [3] and is not changed.
Patch [3/7]:
Add missing of freeing an allocated ttyname buffer on trigger
deactivation. This is a memory leak fix patch and should also be
backported to the 'stable' branches.
Patch [4/7]:
As requested by greg k-h this is more a 'dev_warn' instead of a
'dev_info'. This could also be backported to the 'stable' branches if
needed.
Patch [5/7]:
Use a completion to sync for sysfs read/write and the delay scheduler
work. I hope I am using the completion correctly. I wasn't sure if I
should secure the sysfs read and write access at the same time via a
mutex. With this change, the work is also not stopped as it was before
when no ttyname was set via sysfs. A tty should always be set when this
trigger is used. And is therefore not a problem from my point of view.
Patch [6/7]:
Make rx tx activitate configurable. In the previous implementation,
there was still the ttytrigger flag variable. This flag variable was
replaced by individual variables in the data struct. Now these variables
can be accessed without masking. The commit was rebased and cleaned up
to use the completion implementation.
Patch [7/7]:
Adding additional trigger line state sources. The commit was also
rebased and cleaned up to use the completion implementation.
Changes in v5:
==============
v5: https://lore.kernel.org/linux-leds/[email protected]/
- Update commit message as request by greg k-h, to make the commit
message more generic and not focusing on my use case [2].
- Removing PATCH v4 1/3 from previous set. This has been already applied
to tty-testing [3] by greg k-h.
- As requested by greq k-h. I have also made the following changes to
PATCH v4 3/3 [4].
* Add a comment to the enum that this is already used for bit
evaluation and sysfs read and write.
* Renaming the variable 'unsigned long mode' to
'unsigned long ttytrigger' in the ledtrig_tty_data structure to make
it clearer that the selected triggers are stored there.
* Using sysfs_emit() function to dump the requestd ttytrigger to
userland.
* Also using the kstrtobool() function to write the selected
ttytrigger via the sysfs. This values are booleans.
- I also removed the function ledtrig_tty_evaluate() from my last
patchses PATCH v4 3/3 [4]. The new API tty_get_tiocm() function
is only called once now and checked for each ttytrigger bit.
Previously this function was called for each bit, which is not
necessary.
Links:
[2] https://lore.kernel.org/linux-leds/2023102115-stock-scrambled-f7d5@gregkh/
[3] https://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty.git/commit/?h=tty-testing&id=838eb763c3e939a8de8d4c55a17ddcce737685c1
[4] https://lore.kernel.org/linux-leds/[email protected]/
Changes in v4:
==============
v4: https://lore.kernel.org/linux-leds/[email protected]/
- Merging patch 3/4 into patch number 4/4 from previous series, because
it fixes a problem that does not exist upstream. This was a note from
the build robot regarding my change that I added with previous series.
This change was never upstream and therefore this is not relevant.
- Update the commit message of patch 1/3 of this series, that this
commit
also changes the 'ndashes' to simple dashes. There were no changes, so
I add the 'Reviewed-by' that the commit received before.
- With this patchset version I have reworked my implementation for the
evaluation of the additional line state, so that this changes becomes
smaller. As basis I have used the staged commits from Christian Marangi
that makes this changes to the netdev trigger. This has already been
applied to 'for-leds-next-next' by Lee Jones. I adapted this to the
tty trigger.
Convert device attr to macro:
https://git.kernel.org/pub/scm/linux/kernel/git/lee/leds.git/commit/drivers/leds/trigger?h=for-leds-next-next&id=509412749002f4bac4c29f2012fff90c08d8afca
Unify sysfs and state handling:
https://git.kernel.org/pub/scm/linux/kernel/git/lee/leds.git/commit/drivers/leds/trigger?h=for-leds-next-next&id=0fd93ac8582627bee9a3c824489f302dff722881
Changes in v3:
==============
v3: https://lore.kernel.org/linux-leds/[email protected]/
- Add missing 'kernel test robot' information to the commit message.
- Additional information added to the commit message
Changes in v2:
==============
v2: https://lore.kernel.org/linux-leds/[email protected]/
- rename new function from tty_get_mget() to tty_get_tiocm() as
requested by 'Jiri Slaby'.
- As suggested by 'Jiri Slaby', fixed tabs in function documentation
throughout the file '/drivers/tty/tty_io.c' in a separate commit.
- Move the variable definition to the top in function
'ledtrig_tty_work()'.
This was reported by the 'kernel test robot' after my change in v1.
- Also set the 'max_brightness' to 'blink_brightness' if no
'blink_brightness' was set. This fixes a problem at startup when the
brightness is still set to 0 and only 'line_*' is evaluated. I looked
in the netdev trigger and that's exactly how it's done there.
Changes in v1:
==============
v1: https://lore.kernel.org/linux-leds/[email protected]/
This is a follow-up patchset, based on the mailing list discussion from
March 2023 based on the old patchset v8 [1]. I have changed, the LED
trigger handling via the sysfs interfaces as suggested by Uwe
Kleine-König.
Links:
[1] https://lore.kernel.org/linux-leds/[email protected]/
*** BLURB HERE ***
Florian Eckert (4):
tty: add new helper function tty_get_tiocm
leds: ledtrig-tty: replace mutex with completion
leds: ledtrig-tty: make rx tx activitate configurable
leds: ledtrig-tty: add additional line state evaluation
.../ABI/testing/sysfs-class-led-trigger-tty | 56 ++++
drivers/leds/trigger/ledtrig-tty.c | 243 +++++++++++++++---
drivers/tty/tty_io.c | 28 +-
include/linux/tty.h | 1 +
4 files changed, 285 insertions(+), 43 deletions(-)
base-commit: 2cc14f52aeb78ce3f29677c2de1f06c0e91471ab
--
2.30.2
The serial tty interface also supports additional input signals, that
can also be evaluated within this trigger. This change is adding the
following additional input sources, which could be controlled
via the '/sys/class/<leds>/' sysfs interface.
Explanation:
DCE = Data Communication Equipment (Modem)
DTE = Data Terminal Equipment (Computer)
- cts:
DCE is ready to accept data from the DTE (CTS = Clear To Send). If
the line state is detected, the LED is switched on.
If set to 0 (default), the LED will not evaluate CTS.
If set to 1, the LED will evaluate CTS.
- dsr:
DCE is ready to receive and send data (DSR = Data Set Ready). If the
line state is detected, the LED is switched on.
If set to 0 (default), the LED will not evaluate DSR.
If set to 1, the LED will evaluate DSR.
- dcd:
DTE is receiving a carrier from the DCE (DCD = Data Carrier Detect).
If the line state is detected, the LED is switched on.
If set to 0 (default), the LED will not evaluate DCD.
If set to 1, the LED will evaluate DCD.
- rng:
DCE has detected an incoming ring signal on the telephone line
(RNG = Ring Indicator). If the line state is detected, the LED is
switched on.
If set to 0 (default), the LED will not evaluate RNG.
If set to 1, the LED will evaluate RNG.
Also add an invert flag on LED blink, so that the LED blinks in the
correct order.
* If one off the new enabled input signals are evaluatet as 'enabled',
and data are transmitted, then the LED should first blink 'off' and
then 'on' (invert).
* If all the new enabled input signals are evaluatet as 'disabled',
and data are transmitted, then the LED should first blink 'on' and
then 'off'.
Signed-off-by: Florian Eckert <[email protected]>
Reviewed-by: Maarten Brock <[email protected]>
---
.../ABI/testing/sysfs-class-led-trigger-tty | 40 ++++++++++
drivers/leds/trigger/ledtrig-tty.c | 78 ++++++++++++++++++-
2 files changed, 117 insertions(+), 1 deletion(-)
diff --git a/Documentation/ABI/testing/sysfs-class-led-trigger-tty b/Documentation/ABI/testing/sysfs-class-led-trigger-tty
index 504dece151b8..30cef9ac0f49 100644
--- a/Documentation/ABI/testing/sysfs-class-led-trigger-tty
+++ b/Documentation/ABI/testing/sysfs-class-led-trigger-tty
@@ -20,3 +20,43 @@ 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.
+
+What: /sys/class/leds/<led>/cts
+Date: February 2024
+KernelVersion: 6.8
+Description:
+ CTS = Clear To Send
+ DCE is ready to accept data from the DTE.
+ If the line state is detected, the LED is switched on.
+ If set to 0 (default), the LED will not evaluate CTS.
+ If set to 1, the LED will evaluate CTS.
+
+What: /sys/class/leds/<led>/dsr
+Date: February 2024
+KernelVersion: 6.8
+Description:
+ DSR = Data Set Ready
+ DCE is ready to receive and send data.
+ If the line state is detected, the LED is switched on.
+ If set to 0 (default), the LED will not evaluate DSR.
+ If set to 1, the LED will evaluate DSR.
+
+What: /sys/class/leds/<led>/dcd
+Date: February 2024
+KernelVersion: 6.8
+Description:
+ DCD = Data Carrier Detect
+ DTE is receiving a carrier from the DCE.
+ If the line state is detected, the LED is switched on.
+ If set to 0 (default), the LED will not evaluate CAR (DCD).
+ If set to 1, the LED will evaluate CAR (DCD).
+
+What: /sys/class/leds/<led>/rng
+Date: February 2024
+KernelVersion: 6.8
+Description:
+ RNG = Ring Indicator
+ DCE has detected an incoming ring signal on the telephone
+ line. If the line state is detected, the LED is switched on.
+ If set to 0 (default), the LED will not evaluate RNG.
+ If set to 1, the LED will evaluate RNG.
diff --git a/drivers/leds/trigger/ledtrig-tty.c b/drivers/leds/trigger/ledtrig-tty.c
index ee6d01ecb309..e30926424c48 100644
--- a/drivers/leds/trigger/ledtrig-tty.c
+++ b/drivers/leds/trigger/ledtrig-tty.c
@@ -19,17 +19,26 @@ struct ledtrig_tty_data {
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)
@@ -111,6 +120,18 @@ static ssize_t ledtrig_tty_attr_show(struct device *dev, char *buf,
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);
@@ -134,6 +155,18 @@ static ssize_t ledtrig_tty_attr_store(struct device *dev, const char *buf,
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;
@@ -154,6 +187,10 @@ static ssize_t ledtrig_tty_attr_store(struct device *dev, const char *buf,
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)
{
@@ -161,6 +198,8 @@ static void ledtrig_tty_work(struct work_struct *work)
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)
@@ -188,6 +227,33 @@ static void ledtrig_tty_work(struct work_struct *work)
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;
@@ -197,11 +263,13 @@ static void ledtrig_tty_work(struct work_struct *work)
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;
}
}
@@ -210,7 +278,11 @@ static void ledtrig_tty_work(struct work_struct *work)
switch (state) {
case TTY_LED_BLINK:
led_blink_set_oneshot(trigger_data->led_cdev, &interval,
- &interval, 0);
+ &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;
@@ -228,6 +300,10 @@ 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);
--
2.30.2
On Mon, Nov 27, 2023 at 12:03:07PM +0100, Florian Eckert wrote:
> Changes in v9:
> ==============
> - As requested, I have removed the memory leak fix patch from the previous
> patch series v8 and have send this patch directly to the stable
> mailinglist [10].
> - I also have removed the not needed wait for completion code path on
> sysfs attr store and show, for the new configuration options, as
> requested by greg k-h [11].
> - Patch v8 3/6 dropped, because the change is not correct as mentiond
> by greg k-h [12] and this part of the code will be removed anyway
> in this patch series.
> - Update naming of the function ledtrig_tty_waitforcompletion() to
> ledtrig_tty_wait_for_completion() which match better with the API call
> function wait_for_completion_timeout().
>
> Thanks to all reviewers for the suggestions for improvement :+1: of this
> patch set.
Nice work, thanks for sticking with it:
Reviewed-by: Greg Kroah-Hartman <[email protected]>
On Mon, 27 Nov 2023 12:03:07 +0100, Florian Eckert wrote:
> Changes in v9:
> ==============
> - As requested, I have removed the memory leak fix patch from the previous
> patch series v8 and have send this patch directly to the stable
> mailinglist [10].
> - I also have removed the not needed wait for completion code path on
> sysfs attr store and show, for the new configuration options, as
> requested by greg k-h [11].
> - Patch v8 3/6 dropped, because the change is not correct as mentiond
> by greg k-h [12] and this part of the code will be removed anyway
> in this patch series.
> - Update naming of the function ledtrig_tty_waitforcompletion() to
> ledtrig_tty_wait_for_completion() which match better with the API call
> function wait_for_completion_timeout().
>
> [...]
Applied, thanks!
[1/4] tty: add new helper function tty_get_tiocm
commit: 5d11a4709f552fa139c2439fead05daeb064a6f4
[2/4] leds: ledtrig-tty: replace mutex with completion
commit: 50744fe65a4c8b78eff9a4b70825dd7c768f9f69
[3/4] leds: ledtrig-tty: make rx tx activitate configurable
commit: 8e7b857c0eafdc49ff0e63e9252ed0273b9efdbd
[4/4] leds: ledtrig-tty: add additional line state evaluation
commit: 7f5a46671b2253989b2674407d624f1fcc77d60f
--
Lee Jones [李琼斯]