History log of /include/linux/leds.h
Revision Date Author Comments
3ef7de5304edf60d0b8674dd7cdacc104e15a93c 20-Aug-2014 Jacek Anaszewski <j.anaszewski@samsung.com> leds: Improve and export led_update_brightness

led_update_brightness helper function used to be exploited only locally
in the led-class.c module, where its result was being passed to the
brightness_show sysfs callback. With the introduction of v4l2-flash
subdevice the same functionality becomes required for reading current
brightness from a LED device. This patch adds checking of return value
of the brightness_get callback and moves the led_update_brightness()
function to the LED subsystem public API.

Signed-off-by: Jacek Anaszewski <j.anaszewski@samsung.com>
Acked-by: Kyungmin Park <kyungmin.park@samsung.com>
Cc: Richard Purdie <rpurdie@rpsys.net>
Signed-off-by: Bryan Wu <cooloney@gmail.com>
d8082827d8a214343b761f2c4554d2a7d1573d63 07-Aug-2014 Jacek Anaszewski <j.anaszewski@samsung.com> leds: make brightness type consistent across whole subsystem

Documentations states that brightness units type is enum led_brightness
and this is the type used by the led API functions. Adjust the type
of brightness variables in the struct led_classdev accordingly.

Signed-off-by: Jacek Anaszewski <j.anaszewski@samsung.com>
Acked-by: Kyungmin Park <kyungmin.park@samsung.com>
Cc: Richard Purdie <rpurdie@rpsys.net>
Signed-off-by: Bryan Wu <cooloney@gmail.com>
047133066e6c2549403fe5a2d619f47ba4212ef5 07-Aug-2014 Jacek Anaszewski <j.anaszewski@samsung.com> leds: Reorder include directives

Reorder include directives so that they are arranged
in alphabetical order.

Signed-off-by: Jacek Anaszewski <j.anaszewski@samsung.com>
Acked-by: Kyungmin Park <kyungmin.park@samsung.com>
Cc: Richard Purdie <rpurdie@rpsys.net>
Signed-off-by: Bryan Wu <cooloney@gmail.com>
9067359faf890b3a18ab38c792d458fba77b32b4 02-Sep-2014 Jiri Kosina <jkosina@suse.cz> Revert "leds: convert blink timer to workqueue"

This reverts commit 8b37e1bef5a6b60e949e28a4db3006e4b00bd758.

It's broken as it changes led_blink_set() in a way that it can now sleep
(while synchronously waiting for workqueue to be cancelled). That's a
problem, because it's possible that this function gets called from atomic
context (tpt_trig_timer() takes a readlock and thus disables preemption).

This has been brought up 3 weeks ago already [1] but no proper fix has
materialized, and I keep seeing the problem since 3.17-rc1.

[1] https://lkml.org/lkml/2014/8/16/128

BUG: sleeping function called from invalid context at kernel/workqueue.c:2650
in_atomic(): 1, irqs_disabled(): 0, pid: 2335, name: wpa_supplicant
5 locks held by wpa_supplicant/2335:
#0: (rtnl_mutex){+.+.+.}, at: [<ffffffff814c7c92>] rtnl_lock+0x12/0x20
#1: (&wdev->mtx){+.+.+.}, at: [<ffffffffc06e649c>] cfg80211_mgd_wext_siwessid+0x5c/0x180 [cfg80211]
#2: (&local->mtx){+.+.+.}, at: [<ffffffffc0817dea>] ieee80211_prep_connection+0x17a/0x9a0 [mac80211]
#3: (&local->chanctx_mtx){+.+.+.}, at: [<ffffffffc08081ed>] ieee80211_vif_use_channel+0x5d/0x2a0 [mac80211]
#4: (&trig->leddev_list_lock){.+.+..}, at: [<ffffffffc081e68c>] tpt_trig_timer+0xec/0x170 [mac80211]
CPU: 0 PID: 2335 Comm: wpa_supplicant Not tainted 3.17.0-rc3 #1
Hardware name: LENOVO 7470BN2/7470BN2, BIOS 6DET38WW (2.02 ) 12/19/2008
ffff8800360b5a50 ffff8800751f76d8 ffffffff8159e97f ffff8800360b5a30
ffff8800751f76e8 ffffffff810739a5 ffff8800751f77b0 ffffffff8106862f
ffffffff810685d0 0aa2209200000000 ffff880000000004 ffff8800361c59d0
Call Trace:
[<ffffffff8159e97f>] dump_stack+0x4d/0x66
[<ffffffff810739a5>] __might_sleep+0xe5/0x120
[<ffffffff8106862f>] flush_work+0x5f/0x270
[<ffffffff810685d0>] ? mod_delayed_work_on+0x80/0x80
[<ffffffff810945ca>] ? mark_held_locks+0x6a/0x90
[<ffffffff81068a5f>] ? __cancel_work_timer+0x6f/0x100
[<ffffffff810946ed>] ? trace_hardirqs_on_caller+0xfd/0x1c0
[<ffffffff81068a6b>] __cancel_work_timer+0x7b/0x100
[<ffffffff81068b0e>] cancel_delayed_work_sync+0xe/0x10
[<ffffffff8147cf3b>] led_blink_set+0x1b/0x40
[<ffffffffc081e6b0>] tpt_trig_timer+0x110/0x170 [mac80211]
[<ffffffffc081ecdd>] ieee80211_mod_tpt_led_trig+0x9d/0x160 [mac80211]
[<ffffffffc07e4278>] __ieee80211_recalc_idle+0x98/0x140 [mac80211]
[<ffffffffc07e59ce>] ieee80211_idle_off+0xe/0x10 [mac80211]
[<ffffffffc0804e5b>] ieee80211_add_chanctx+0x3b/0x220 [mac80211]
[<ffffffffc08062e4>] ieee80211_new_chanctx+0x44/0xf0 [mac80211]
[<ffffffffc080838a>] ieee80211_vif_use_channel+0x1fa/0x2a0 [mac80211]
[<ffffffffc0817df8>] ieee80211_prep_connection+0x188/0x9a0 [mac80211]
[<ffffffffc081c246>] ieee80211_mgd_auth+0x256/0x2e0 [mac80211]
[<ffffffffc07eab33>] ieee80211_auth+0x13/0x20 [mac80211]
[<ffffffffc06cb006>] cfg80211_mlme_auth+0x106/0x270 [cfg80211]
[<ffffffffc06ce085>] cfg80211_conn_do_work+0x155/0x3b0 [cfg80211]
[<ffffffffc06cf670>] cfg80211_connect+0x3f0/0x540 [cfg80211]
[<ffffffffc06e6148>] cfg80211_mgd_wext_connect+0x158/0x1f0 [cfg80211]
[<ffffffffc06e651e>] cfg80211_mgd_wext_siwessid+0xde/0x180 [cfg80211]
[<ffffffffc06e36c0>] ? cfg80211_wext_giwessid+0x50/0x50 [cfg80211]
[<ffffffffc06e36dd>] cfg80211_wext_siwessid+0x1d/0x40 [cfg80211]
[<ffffffff81584d0c>] ioctl_standard_iw_point+0x14c/0x3e0
[<ffffffff810946ed>] ? trace_hardirqs_on_caller+0xfd/0x1c0
[<ffffffff8158502a>] ioctl_standard_call+0x8a/0xd0
[<ffffffff81584fa0>] ? ioctl_standard_iw_point+0x3e0/0x3e0
[<ffffffff81584b76>] wireless_process_ioctl.constprop.10+0xb6/0x100
[<ffffffff8158521d>] wext_handle_ioctl+0x5d/0xb0
[<ffffffff814cfb29>] dev_ioctl+0x329/0x620
[<ffffffff810946ed>] ? trace_hardirqs_on_caller+0xfd/0x1c0
[<ffffffff8149c7f2>] sock_ioctl+0x142/0x2e0
[<ffffffff811b0140>] do_vfs_ioctl+0x300/0x520
[<ffffffff815a67fb>] ? sysret_check+0x1b/0x56
[<ffffffff810946ed>] ? trace_hardirqs_on_caller+0xfd/0x1c0
[<ffffffff811b03e1>] SyS_ioctl+0x81/0xa0
[<ffffffff815a67d6>] system_call_fastpath+0x1a/0x1f
wlan0: send auth to 00:0b:6b:3c:8c:e4 (try 1/3)
wlan0: authenticated
wlan0: associate with 00:0b:6b:3c:8c:e4 (try 1/3)
wlan0: RX AssocResp from 00:0b:6b:3c:8c:e4 (capab=0x431 status=0 aid=2)
wlan0: associated
IPv6: ADDRCONF(NETDEV_CHANGE): wlan0: link becomes ready
cfg80211: Calling CRDA for country: NA
wlan0: Limiting TX power to 27 (27 - 0) dBm as advertised by 00:0b:6b:3c:8c:e4

=================================
[ INFO: inconsistent lock state ]
3.17.0-rc3 #1 Not tainted
---------------------------------
inconsistent {SOFTIRQ-ON-W} -> {IN-SOFTIRQ-W} usage.
swapper/0/0 [HC0[0]:SC1[1]:HE1:SE0] takes:
((&(&led_cdev->blink_work)->work)){+.?...}, at: [<ffffffff810685d0>] flush_work+0x0/0x270
{SOFTIRQ-ON-W} state was registered at:
[<ffffffff81094dbe>] __lock_acquire+0x30e/0x1a30
[<ffffffff81096c81>] lock_acquire+0x91/0x110
[<ffffffff81068608>] flush_work+0x38/0x270
[<ffffffff81068a6b>] __cancel_work_timer+0x7b/0x100
[<ffffffff81068b0e>] cancel_delayed_work_sync+0xe/0x10
[<ffffffff8147cf3b>] led_blink_set+0x1b/0x40
[<ffffffffc081e6b0>] tpt_trig_timer+0x110/0x170 [mac80211]
[<ffffffffc081ecdd>] ieee80211_mod_tpt_led_trig+0x9d/0x160 [mac80211]
[<ffffffffc07e4278>] __ieee80211_recalc_idle+0x98/0x140 [mac80211]
[<ffffffffc07e59ce>] ieee80211_idle_off+0xe/0x10 [mac80211]
[<ffffffffc0804e5b>] ieee80211_add_chanctx+0x3b/0x220 [mac80211]
[<ffffffffc08062e4>] ieee80211_new_chanctx+0x44/0xf0 [mac80211]
[<ffffffffc080838a>] ieee80211_vif_use_channel+0x1fa/0x2a0 [mac80211]
[<ffffffffc0817df8>] ieee80211_prep_connection+0x188/0x9a0 [mac80211]
[<ffffffffc081c246>] ieee80211_mgd_auth+0x256/0x2e0 [mac80211]
[<ffffffffc07eab33>] ieee80211_auth+0x13/0x20 [mac80211]
[<ffffffffc06cb006>] cfg80211_mlme_auth+0x106/0x270 [cfg80211]
[<ffffffffc06ce085>] cfg80211_conn_do_work+0x155/0x3b0 [cfg80211]
[<ffffffffc06cf670>] cfg80211_connect+0x3f0/0x540 [cfg80211]
[<ffffffffc06e6148>] cfg80211_mgd_wext_connect+0x158/0x1f0 [cfg80211]
[<ffffffffc06e651e>] cfg80211_mgd_wext_siwessid+0xde/0x180 [cfg80211]
[<ffffffffc06e36dd>] cfg80211_wext_siwessid+0x1d/0x40 [cfg80211]
[<ffffffff81584d0c>] ioctl_standard_iw_point+0x14c/0x3e0
[<ffffffff8158502a>] ioctl_standard_call+0x8a/0xd0
[<ffffffff81584b76>] wireless_process_ioctl.constprop.10+0xb6/0x100
[<ffffffff8158521d>] wext_handle_ioctl+0x5d/0xb0
[<ffffffff814cfb29>] dev_ioctl+0x329/0x620
[<ffffffff8149c7f2>] sock_ioctl+0x142/0x2e0
[<ffffffff811b0140>] do_vfs_ioctl+0x300/0x520
[<ffffffff811b03e1>] SyS_ioctl+0x81/0xa0
[<ffffffff815a67d6>] system_call_fastpath+0x1a/0x1f
irq event stamp: 493416
hardirqs last enabled at (493416): [<ffffffff81068a5f>] __cancel_work_timer+0x6f/0x100
hardirqs last disabled at (493415): [<ffffffff81067e9f>] try_to_grab_pending+0x1f/0x160
softirqs last enabled at (493408): [<ffffffff81053ced>] _local_bh_enable+0x1d/0x50
softirqs last disabled at (493409): [<ffffffff81054c75>] irq_exit+0xa5/0xb0

other info that might help us debug this:
Possible unsafe locking scenario:

CPU0
----
lock((&(&led_cdev->blink_work)->work));
<Interrupt>
lock((&(&led_cdev->blink_work)->work));

*** DEADLOCK ***

2 locks held by swapper/0/0:
#0: (((&tpt_trig->timer))){+.-...}, at: [<ffffffff810b4c50>] call_timer_fn+0x0/0x180
#1: (&trig->leddev_list_lock){.+.?..}, at: [<ffffffffc081e68c>] tpt_trig_timer+0xec/0x170 [mac80211]

stack backtrace:
CPU: 0 PID: 0 Comm: swapper/0 Not tainted 3.17.0-rc3 #1
Hardware name: LENOVO 7470BN2/7470BN2, BIOS 6DET38WW (2.02 ) 12/19/2008
ffffffff8246eb30 ffff88007c203b00 ffffffff8159e97f ffffffff81a194c0
ffff88007c203b50 ffffffff81599c29 0000000000000001 ffffffff00000001
ffff880000000000 0000000000000006 ffffffff81a194c0 ffffffff81093ad0
Call Trace:
<IRQ> [<ffffffff8159e97f>] dump_stack+0x4d/0x66
[<ffffffff81599c29>] print_usage_bug+0x1f4/0x205
[<ffffffff81093ad0>] ? check_usage_backwards+0x140/0x140
[<ffffffff810944d3>] mark_lock+0x223/0x2b0
[<ffffffff81094d60>] __lock_acquire+0x2b0/0x1a30
[<ffffffff81096c81>] lock_acquire+0x91/0x110
[<ffffffff810685d0>] ? mod_delayed_work_on+0x80/0x80
[<ffffffffc081e5a0>] ? __ieee80211_get_rx_led_name+0x10/0x10 [mac80211]
[<ffffffff81068608>] flush_work+0x38/0x270
[<ffffffff810685d0>] ? mod_delayed_work_on+0x80/0x80
[<ffffffff810945ca>] ? mark_held_locks+0x6a/0x90
[<ffffffff81068a5f>] ? __cancel_work_timer+0x6f/0x100
[<ffffffffc081e5a0>] ? __ieee80211_get_rx_led_name+0x10/0x10 [mac80211]
[<ffffffff8109469d>] ? trace_hardirqs_on_caller+0xad/0x1c0
[<ffffffffc081e5a0>] ? __ieee80211_get_rx_led_name+0x10/0x10 [mac80211]
[<ffffffff81068a6b>] __cancel_work_timer+0x7b/0x100
[<ffffffff81068b0e>] cancel_delayed_work_sync+0xe/0x10
[<ffffffff8147cf3b>] led_blink_set+0x1b/0x40
[<ffffffffc081e6b0>] tpt_trig_timer+0x110/0x170 [mac80211]
[<ffffffff810b4cc5>] call_timer_fn+0x75/0x180
[<ffffffff810b4c50>] ? process_timeout+0x10/0x10
[<ffffffffc081e5a0>] ? __ieee80211_get_rx_led_name+0x10/0x10 [mac80211]
[<ffffffff810b50ac>] run_timer_softirq+0x1fc/0x2f0
[<ffffffff81054805>] __do_softirq+0x115/0x2e0
[<ffffffff81054c75>] irq_exit+0xa5/0xb0
[<ffffffff810049b3>] do_IRQ+0x53/0xf0
[<ffffffff815a74af>] common_interrupt+0x6f/0x6f
<EOI> [<ffffffff8147b56e>] ? cpuidle_enter_state+0x6e/0x180
[<ffffffff8147b732>] cpuidle_enter+0x12/0x20
[<ffffffff8108bba0>] cpu_startup_entry+0x330/0x360
[<ffffffff8158fb51>] rest_init+0xc1/0xd0
[<ffffffff8158fa90>] ? csum_partial_copy_generic+0x170/0x170
[<ffffffff81af3ff2>] start_kernel+0x44f/0x45a
[<ffffffff81af399c>] ? set_init_arg+0x53/0x53
[<ffffffff81af35ad>] x86_64_start_reservations+0x2a/0x2c
[<ffffffff81af36a0>] x86_64_start_kernel+0xf1/0xf4

Cc: Vincent Donnefort <vdonnefort@gmail.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Tejun Heo <tj@kernel.org>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
Signed-off-by: Bryan Wu <cooloney@gmail.com>
8b37e1bef5a6b60e949e28a4db3006e4b00bd758 14-Jun-2014 Vincent Donnefort <vdonnefort@gmail.com> leds: convert blink timer to workqueue

This patch converts the blink timer from led-core to workqueue which is more
suitable for this kind of non-priority operations. Moreover, timer may lead to
errors when a LED setting function use a scheduling function such as pinctrl
which is using mutex.

Signed-off-by: Vincent Donnefort <vdonnefort@gmail.com>
Signed-off-by: Bryan Wu <cooloney@gmail.com>
d0d480cce8f522b37c2c1de38230fc9ad15fa506 25-Jun-2014 Johan Hovold <johan@kernel.org> leds: add led-class attribute-group support

Allow led-class devices to be created with optional attribute groups.

This is needed in order to allow led drivers to create custom device
attributes in a race-free manner.

Signed-off-by: Johan Hovold <johan@kernel.org>
Signed-off-by: Bryan Wu <cooloney@gmail.com>
48a1d032c954b9b06c3adbf35ef4735dd70ab757 14-Mar-2013 Kim, Milo <Milo.Kim@ti.com> leds: add camera LED triggers

Some LED devices support flash/torch functionality through the LED subsystem.
This patch enables direct LED trigger controls by the driver.
Flash on/off and torch on/off can be done simply by other driver space.
Two trigger APIs are added, ledtrig_flash_ctrl() and ledtrig_torch_ctrl().

Signed-off-by: Milo(Woogyom) Kim <milo.kim@ti.com>
Signed-off-by: Bryan Wu <cooloney@gmail.com>
39f7e08af3fd9ca1cb94a8270354afb2ea5cfcd3 14-Mar-2013 Kim, Milo <Milo.Kim@ti.com> leds: trigger: use inline functions instead of macros

Macros are used in case that an inline function doesn't work.
Otherwise, use an empty inline function.

(a) Case of !CONFIG_LEDS_TRIGGERS
Following macros are replaced with inline functions.
led_trigger_register_simple()
led_trigger_unregister_simple()
led_trigger_event()
To make inline types, the structure, 'led_trigger' should be defined.
This structure has no member at all.

(b) Case of !CONFIG_LEDS_TRIGGER_IDE_DISK
ledtrig_ide_activity() macro is replaced with an inline function as well.

(c) DEFINE_LED_TRIGGER() and DEFINE_LED_TRIGGER_GLOBAL()
Struct 'led_trigger' is defined both cases, with CONFIG_LEDS_TRIGGERS and
without CONFIG_LEDS_TRIGGERS.
Those macros are moved out of CONFIG_LED_TRIGGERS because of no-dependency
on CONFIG_LEDS_TRIGGERS.

(d) Fix build errors in mmc-core driver
After replacing macros with inline functions, following build errors occur.
(condition: CONFIG_LEDS_TRIGGERS is not set)

drivers/mmc/core/core.c: In function 'mmc_request_done':
drivers/mmc/core/core.c:164:25: error: 'struct mmc_host' has no member named 'led'
drivers/mmc/core/core.c: In function 'mmc_start_request':
drivers/mmc/core/core.c:254:24: error: 'struct mmc_host' has no member named 'led'
make[3]: *** [drivers/mmc/core/core.o] Error 1

The reason of these errors is non-existent member variable, 'led'.
It is only valid when CONFIG_LEDS_TRIGGERS is set.
But now, it can be used without this dependency.
To fix build errors, member 'led' is always used without its config option in
'include/linux/mmc/host.h'.

Signed-off-by: Milo(Woogyom) Kim <milo.kim@ti.com>
Signed-off-by: Bryan Wu <cooloney@gmail.com>
057407c732b7761cf417a1e6633a02d9d473340d 19-Nov-2012 Jingoo Han <jg1.han@samsung.com> led: Add dependency on CONFIG_LEDS_TRIGGERS to led_trigger_rename_static()

This patch fixes build warnings when CONFIG_LEDS_TRIGGERS is
disabled as below:
include/linux/leds.h:158:18: warning: 'struct led_trigger' declared inside parameter list [enabled by default]
include/linux/leds.h:158:18: warning: its scope is only this definition or declaration, which is probably not what you want [enabled
by default]

Signed-off-by: Jingoo Han <jg1.han@samsung.com>
Acked-by: Fabio Baltieri <fabio.baltieri@gmail.com>
Signed-off-by: Bryan Wu <cooloney@gmail.com>
a8df7b1ab70bfd6f261fa5e96985fca638299acc 04-Nov-2012 Fabio Baltieri <fabio.baltieri@gmail.com> leds: add led_trigger_rename function

Implements a "led_trigger_rename" function to rename a trigger with
proper locking.

This assumes that led name was originally allocated in non-constant
storage.

Signed-off-by: Fabio Baltieri <fabio.baltieri@gmail.com>
Cc: Kurt Van Dijck <kurt.van.dijck@eia.be>
Signed-off-by: Bryan Wu <cooloney@gmail.com>
d23a22a74fded23a12434c9463fe66cec2b0afcd 15-Aug-2012 Fabio Baltieri <fabio.baltieri@gmail.com> leds: delay led_set_brightness if stopping soft-blink

Delay execution of led_set_brightness() if need to stop soft-blink
timer.

This allows led_set_brightness to be called in hard-irq context even if
soft-blink was activated on that LED.

Signed-off-by: Fabio Baltieri <fabio.baltieri@gmail.com>
Cc: Pawel Moll <pawel.moll@arm.com>
Signed-off-by: Bryan Wu <bryan.wu@canonical.com>
8f88731d052d2b14f332249a9332690ac1b365ac 25-Jun-2011 Bryan Wu <bryan.wu@canonical.com> led-triggers: create a trigger for CPU activity

Attempting to consolidate the ARM LED code, this removes the
custom RealView LED trigger code to turn LEDs on and off in
response to CPU activity and replace it with a standard trigger.

(bryan.wu@canonical.com:
It introduces several syscore stubs into this trigger.
It also provides ledtrig_cpu trigger event stub in <linux/leds.h>.
Although it was inspired by ARM work, it can be used in other arch.)

Cc: Richard Purdie <rpurdie@rpsys.net>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Bryan Wu <bryan.wu@canonical.com>
Reviewed-by: Jamie Iles <jamie@jamieiles.com>
Tested-by: Jochen Friedrich <jochen@scram.de>
19cd67e2d51225b164560b54b85f943e07deee8a 13-Jun-2012 Shuah Khan <shuahkhan@gmail.com> leds: Rename led_brightness_set() to led_set_brightness()

Rename leds external interface led_brightness_set() to led_set_brightness().
This is the second phase of the change to reduce confusion between the
leds internal and external interfaces that set brightness. With this change,
now the external interface is led_set_brightness(). The first phase renamed
the internal interface led_set_brightness() to __led_set_brightness().
There are no changes to the interface implementations.

Signed-off-by: Shuah Khan <shuahkhan@gmail.com>
Signed-off-by: Bryan Wu <bryan.wu@canonical.com>
5bb629c504394f4d42c53a25d75ccb02a393f92f 27-May-2012 Fabio Baltieri <fabio.baltieri@gmail.com> leds: add oneshot blink functions

Add two new functions, led_blink_set_oneshot and
led_trigger_blink_oneshot, to be used by triggers for one-shot blink of
led devices.

This is implemented extending the existing software-blink code, and uses
the same timer and handler function.

The behavior of the code is to do a blink-on, blink-off sequence when
the function is called, ignoring other calls until the sequence is
completed so that the leds keep blinking at constant rate if the
functions are called repeatedly.

This is meant to be used by drivers which needs to trigger on sporadic
event, but doesn't have clear busy/idle trigger points.

After the blink sequence the led remains off. This behavior can be
inverted setting the "invert" argument, which blink the led off, than on
and leave the led on after the sequence.

(bryan.wu@canonical.com: rebase to commit 'leds: don't disable blinking
when writing the same value to delay_on or delay_off')

Signed-off-by: Fabio Baltieri <fabio.baltieri@gmail.com>
Acked-by: Shuah Khan <shuahkhan@gmail.com>
Signed-off-by: Bryan Wu <bryan.wu@canonical.com>
b00961824a33aadec4a825eaeccfbe3db8ec7032 30-May-2012 Shuah Khan <shuahkhan@gmail.com> leds: add new field to led_classdev struct to save activation state

Add a new field to led_classdev to save activattion state after activate
routine is successful. This saved state is used in deactivate routine to
do cleanup such as removing device files, and free memory allocated during
activation. Currently trigger_data not being null is used for this
purpose.

Existing triggers will need changes to use this new field.

Signed-off-by: Shuah Khan <shuahkhan@gmail.com>
Cc: Richard Purdie <rpurdie@rpsys.net>
Cc: Bryan Wu <bryan.wu@canonical.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
4440673a95e63ad888a41db596edaa0c55d3a332 25-May-2011 Uwe Kleine-König <u.kleine-koenig@pengutronix.de> leds: provide helper to register "leds-gpio" devices

This function makes a deep copy of the platform data to allow it to live
in init memory. For a kernel that supports several machines and so
includes the definition for several leds-gpio devices this saves quite
some memory because all but one definition can be free'd after boot.

As the function is used by arch code it must be builtin and so cannot go
into leds-gpio.c.

[akpm@linux-foundation.org: s/CONFIG_LED_REGISTER_GPIO/CONFIG_LEDS_REGISTER_GPIO/]
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Cc: Russell King <rmk@arm.linux.org.uk>
Acked-by: Richard Purdie <richard.purdie@linuxfoundation.org>
Cc: Fabio Estevam <fabio.estevam@freescale.com>
Cc: Sascha Hauer <s.hauer@pengutronix.de>
Tested-by: H Hartley Sweeten <hartleys@visionengravers.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
9517f925f2eb9ffca78b3f0f9389fc675bcb572c 23-Mar-2011 Uwe Kleine-König <u.kleine-koenig@pengutronix.de> leds: make *struct gpio_led_platform_data.leds const

And fix a typo.

Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Cc: Lars-Peter Clausen <lars@metafoo.de>
Cc: Richard Purdie <rpurdie@rpsys.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
0b9536c957095eb1497828aa51b34ac695f67eae 07-Jan-2011 Vasily Khoruzhick <anarsoul@gmail.com> leds: Add ability to blink via simple trigger

As blink API is now available, it's possible to add ability to blink via
simple trigger.

Signed-off-by: Vasily Khoruzhick <anarsoul@gmail.com>
Signed-off-by: Anton Vorontsov <cbouatmailru@gmail.com>
5ada28bf76752e33dce3d807bf0dfbe6d1b943ad 11-Nov-2010 Johannes Berg <johannes.berg@intel.com> led-class: always implement blinking

Currently, blinking LEDs can be awkward because it is not guaranteed that
all LEDs implement blinking. The trigger that wants it to blink then
needs to implement its own timer solution.

Rather than require that, add led_blink_set() API that triggers can use.
This function will attempt to use hw blinking, but if that fails
implements a timer for it. To stop blinking again, brightness_set() also
needs to be wrapped into API that will stop the software blink.

As a result of this, the timer trigger becomes a very trivial one, and
hopefully we can finally see triggers using blinking as well because it's
always easy to use.

Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Acked-by: Richard Purdie <rpurdie@linux.intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2146325df2c2640059a9e064890c30c6e259b458 22-May-2010 Benjamin Herrenschmidt <benh@kernel.crashing.org> leds: leds-gpio: Change blink_set callback to be able to turn off blinking

The leds-gpio blink_set() callback follows the same prototype as the
main leds subsystem blink_set() one.

The problem is that to stop blink, normally, a leds driver does it
in the brightness_set() callback when asked to set a new fixed value.

However, with leds-gpio, the platform has no hook to do so, as this
later callback results in a standard GPIO manipulation.

This changes the leds-gpio specific callback to take a new argument
that indicates whether the LED should be blinking or not and in what
state it should be set if not. We also update the dns323 platform
which seems to be the only user of this so far.

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Richard Purdie <rpurdie@linux.intel.com>
a1dd8c617217322614f0465ae347895c4b58e1ab 22-Jun-2009 Richard Purdie <rpurdie@linux.intel.com> leds: Futher document blink_set

Futher document blink_set function pointer

Signed-off-by: Richard Purdie <rpurdie@linux.intel.com>
ed88bae6918fa990cbfe47316bd0f790121aaf00 13-May-2009 Trent Piepho <xyzzy@speakeasy.org> leds: Add options to have GPIO LEDs start on or keep their state

There already is a "default-on" trigger but there are problems with it.

For one, it's a inefficient way to do it and requires led trigger support
to be compiled in.

But the real reason is that is produces a glitch on the LED. The GPIO is
allocate with the LED *off*, then *later* when the trigger runs it is
turned back on. If the LED was already on via the GPIO's reset default or
action of the firmware, this produces a glitch where the LED goes from on
to off to on. While normally this is fast enough that it wouldn't be
noticeable to a human observer, there are still serious problems.

One is that there may be something else on the GPIO line, like a hardware
alarm or watchdog, that is fast enough to notice the glitch.

Another is that the kernel may panic before the LED is turned back on, thus
hanging with the LED in the wrong state. This is not just speculation, but
actually happened to me with an embedded system that has an LED which
should turn off when the kernel finishes booting, which was left in the
incorrect state due to a bug in the OF LED binding code.

We also let GPIO LEDs get their initial value from whatever the current
state of the GPIO line is. On some systems the LEDs are put into some
state by the firmware or hardware before Linux boots, and it is desired to
have them keep this state which is otherwise unknown to Linux.

This requires that the underlying GPIO driver support reading the value of
output GPIOs. Some drivers support this and some do not.

The platform device binding gains a field in the platform data
"default_state" that controls this. There are three constants defined to
select from on, off, or keeping the current state. The OpenFirmware
binding uses a property named "default-state" that can be set to "on",
"off", or "keep". The default if the property isn't present is off.

Signed-off-by: Trent Piepho <xyzzy@speakeasy.org>
Acked-by: Grant Likely <grant.likely@secretlab.ca>
Acked-by: Wolfram Sang <w.sang@pengutronix.de>
Acked-by: Sean MacLennan <smaclennan@pikatech.com>
Signed-off-by: Richard Purdie <rpurdie@linux.intel.com>
92722b1bb1ebcba767f9c6ee499992ee33367268 11-Jun-2009 Mark Brown <broonie@opensource.wolfsonmicro.com> leds: Further document parameters for blink_set()

The documentation for the parameters of blink_set() was a bit hard
to find so put some where I'd expected to find it.

Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Signed-off-by: Richard Purdie <rpurdie@linux.intel.com>
defb512d2576992c63ba1c18c24eea31cfeaa26e 17-Feb-2009 Richard Purdie <rpurdie@linux.intel.com> leds: Add suspend/resume state flags to leds-gpio

Add an option to preserve LED state when suspending/resuming to the LED
gpio driver. Based on a suggestion from Robert Jarzmik.

Tested-by: Robert Jarzmik <robert.jarzmik@free.fr>
Signed-off-by: Richard Purdie <rpurdie@linux.intel.com>
1bd465e6b0e2b559db47420fea686507a01cfab0 10-Jan-2009 Guennadi Liakhovetski <lg@denx.de> leds: allow led-drivers to use a variable range of brightness values

This patch allows drivers to override the default maximum brightness value
of 255. We take care to preserve backwards-compatibility as much as
possible, so that user-space ABI doesn't change for existing drivers.
LED trigger code has also been updated to use the per-LED maximum.

Signed-off-by: Guennadi Liakhovetski <lg@denx.de>
Signed-off-by: Richard Purdie <rpurdie@linux.intel.com>
859cb7f2a4244ea6da206d3fe9cc8a6810947a68 08-Jan-2009 Richard Purdie <rpurdie@linux.intel.com> leds: Add suspend/resume to the core class

Add suspend/resume to the core class and remove all the now unneeded
code from various drivers. Originally the class code couldn't support
suspend/resume but since class_device can there is no reason for
each driver doing its own suspend/resume anymore.
e2387d6c20752ccdb2895ba5de664fa39652f4cc 17-Nov-2008 Wolfram Sang <w.sang@pengutronix.de> leds: Make header variable naming consistent

There is one place where the struct led_classdev as the function
argument is named differently. Fix it.

Signed-off-by: Wolfram Sang <w.sang@pengutronix.de>
Signed-off-by: Richard Purdie <rpurdie@linux.intel.com>
326bb8a5a12c6298a6bf6c74af490b1858b2f12c 13-Oct-2008 Trent Piepho <tpiepho@freescale.com> leds: Make default trigger fields const

The default_trigger fields of struct gpio_led and thus struct
led_classdev are pretty much always assigned from a string literal,
which means the string can't be modified. Which is fine, since there is
no reason to modify the string and in fact it never is.

But they should be marked const to prevent such code from being added,
to prevent warnings if -Wwrite-strings is used, when assigned from a
constant string other than a string literal (which produces a warning
under current kernel compiler flags), and for general good coding
practices.

Signed-off-by: Trent Piepho <tpiepho@freescale.com>
Signed-off-by: Richard Purdie <rpurdie@linux.intel.com>
f46e9203d9a100bae216cc06e17f2e77351aa8d8 16-Jul-2008 Nate Case <ncase@xes-inc.com> leds: Add support for Philips PCA955x I2C LED drivers

This driver supports the PCA9550, PCA9551, PCA9552, and PCA9553
LED driver chips.

Signed-off-by: Nate Case <ncase@xes-inc.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Richard Purdie <rpurdie@rpsys.net>
781a54e7664cc0089287a90d27086e9656ac68a1 31-May-2008 Anton Vorontsov <avorontsov@ru.mvista.com> leds: mark led_classdev.default_trigger as const

LED classdev core doesn't modify memory pointed by the default_trigger,
so mark it as const and we'll able to pass const char *s without getting
compiler warnings.

Signed-off-by: Anton Vorontsov <avorontsov@ru.mvista.com>
Signed-off-by: Richard Purdie <rpurdie@rpsys.net>
2e214e0fa21465cf2749ca7d5a072cf8591f3213 25-Apr-2008 Richard Purdie <rpurdie@rpsys.net> leds: Document the context brightness_set needs

Make sure there is no confusion about the contexts brightness_set
can be called under by documenting it.

Signed-off-by: Richard Purdie <rpurdie@rpsys.net>
29d76dfa29fe22583aefddccda0bc56aa81035dc 18-Mar-2008 Henrique de Moraes Holschuh <hmh@hmh.eng.br> leds: Add support to leds with readable status

Some led hardware allows drivers to query the led state, and this patch
adds a hook to let the led class take advantage of that information when
available.

Without this functionality, when access to the led hardware is not
exclusive (i.e. firmware or hardware might change its state behind the
kernel's back), reality goes out of sync with the led class' idea of what
the led is doing, which is annoying at best.

Behaviour for drivers that do not or cannot read the led status is
unchanged.

Signed-off-by: Henrique de Moraes Holschuh <hmh@hmh.eng.br>
Signed-off-by: Richard Purdie <rpurdie@rpsys.net>
ca3259b3603539e72faacc6821050ee889a52103 10-Mar-2008 Herbert Valerio Riedel <hvr@gnu.org> leds: enable support for blink_set() platform hook in leds-gpio

Enhance leds-gpio to provide hardware-based led flashing by passing
through the blink_set() call to a optionally set platform-specific
function pointer.

Signed-off-by: Herbert Valerio Riedel <hvr@gnu.org>
Signed-off-by: Richard Purdie <rpurdie@rpsys.net>
b844eba292b477cda14582bfc6f535deed57a82d 23-Mar-2008 Rafael J. Wysocki <rjw@sisk.pl> PM: Remove destroy_suspended_device()

After 2.6.24 there was a plan to make the PM core acquire all device
semaphores during a suspend/hibernation to protect itself from
concurrent operations involving device objects. That proved to be
too heavy-handed and we found a better way to achieve the goal, but
before it happened, we had introduced the functions
device_pm_schedule_removal() and destroy_suspended_device() to allow
drivers to "safely" destroy a suspended device and we had adapted some
drivers to use them. Now that these functions are no longer necessary,
it seems reasonable to remove them and modify their users to use the
normal device unregistration instead.

Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Acked-by: Pavel Machek <pavel@ucw.cz>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
4c79141d28bc290ae307e3f81f5bc909c26faf6e 31-Oct-2007 Márton Németh <nm127@freemail.hu> leds: Add support for hardware accelerated LED flashing

Extends the leds subsystem with a blink_set() callback function which can
be optionally implemented by a LED driver. If implemented, the driver can use
the hardware acceleration for blinking a LED.

Signed-off-by: Márton Németh <nm127@freemail.hu>
Signed-off-by: Richard Purdie <rpurdie@rpsys.net>
fa23f5cce8cda2095013afc837ccf74b352f9f7b 05-Feb-2008 Rafael J. Wysocki <rjw@sisk.pl> leds: add possibility to remove leds classdevs during suspend/resume

Make it possible to unregister a led classdev object in a safe way during a
suspend/resume cycle.

Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Cc: Michael Buesch <mb@bu3sch.de>
Cc: Pavel Machek <pavel@ucw.cz>
Cc: "John W. Linville" <linville@tuxdriver.com>
Cc: Alan Stern <stern@rowland.harvard.edu>
Cc: Len Brown <lenb@kernel.org>
Cc: Greg KH <greg@kroah.com>
Cc: Kay Sievers <kay.sievers@vrfy.org>
Cc: Richard Purdie <rpurdie@rpsys.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
dc47206e552c0850ad11f7e9a1fca0a3c92f5d65 10-Nov-2007 Richard Purdie <rpurdie@rpsys.net> leds: Fix led trigger locking bugs

Convert part of the led trigger core from rw spinlocks to rw
semaphores. We're calling functions which can sleep from invalid
contexts otherwise. Fixes bug #9264.

Signed-off-by: Richard Purdie <rpurdie@rpsys.net>
df96efd73b81b8bc2d23b3d8b6025cce3d43db6c 11-Sep-2007 Yoichi Yuasa <yoichi_yuasa@tripeaks.co.jp> leds: Add missing include for leds.h

This patch has added #include <linux/spinlock.h> to include/linux/leds.h
for rwlock_t.

Signed-off-by: Yoichi Yuasa <yoichi_yuasa@tripeaks.co.jp>
Signed-off-by: Richard Purdie <rpurdie@rpsys.net>
0a3021f4e249fbdb5f30d614707b5e02022e4c9b 16-Jul-2007 Robert P. J. Day <rpjday@mindspring.com> Remove unnecessary includes of spinlock.h under include/linux

Remove the obviously unnecessary includes of <linux/spinlock.h> under the
include/linux/ directory, and fix the couple errors that are introduced as
a result of that.

Signed-off-by: Robert P. J. Day <rpjday@mindspring.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
f8a7c6fe14f556ca8eeddce258cb21392d0c3a2f 09-Jul-2007 Richard Purdie <rpurdie@rpsys.net> leds: Convert from struct class_device to struct device

Convert the LEDs class from struct class_device to struct device
since class_device is scheduled for removal.

Signed-off-by: Richard Purdie <rpurdie@rpsys.net>
Acked-by: Greg Kroah-Hartman <gregkh@suse.de>
22e03f3b58dfcca30f0c8de185022132459638d1 27-Feb-2007 Raphael Assenat <raph@8d.com> leds: Add generic GPIO LED driver

This patch adds support for GPIO connected leds via the new GPIO framework.

Information about leds (gpio, polarity, name, default trigger) is passed
to the driver via platform_data.

Signed-off-by: Raphael Assenat <raph@8d.com>
Signed-off-by: Richard Purdie <rpurdie@rpsys.net>
af410fc13d95f079910fc3dca7496590c3275967 29-Sep-2006 Johannes Berg <johannes@sipsolutions.net> [PATCH] make leds.h include relevant headers

Make it possible to include linux/leds.h without first including list.h and
spinlock.h.

Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Acked-by: Richard Purdie <rpurdie@rpsys.net>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
fb5035dbbea8826cdbeb5c43d7605255eb6f0baa 11-Apr-2006 Ben Dooks <ben-linux@fluff.org> [PATCH] leds: re-layout include/linux/leds.h

Lay out the structure definitions in include/linux/leds.h to be aligned as
much as possible. Also minor updates to the comments to make them more
concise.

Signed-off-by: Ben Dooks <ben-linux@fluff.org>
Acked-by: Richard Purdie <rpurdie@rpsys.net>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2bfb646cdf348cb77c572f06d5b9d17ea205c7e2 31-Mar-2006 Richard Purdie <rpurdie@rpsys.net> [PATCH] LED: Add IDE disk activity LED trigger

Add an LED trigger for IDE disk activity to the ide-disk driver.

Signed-off-by: Richard Purdie <rpurdie@rpsys.net>
Acked-by: Bartlomiej Zolnierkiewicz <B.Zolnierkiewicz@elka.pw.edu.pl>
Cc: Alan Cox <alan@lxorguk.ukuu.org.uk>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
c3bc9956ec52fb2c70f29aa894d8eec766116584 31-Mar-2006 Richard Purdie <rpurdie@rpsys.net> [PATCH] LED: add LED trigger tupport

Add support for LED triggers to the LED subsystem. "Triggers" are events
which change the state of an LED. Two kinds of trigger are available, simple
ones which can be added to exising code with minimum disruption and complex
ones for implementing new or more complex functionality.

Signed-off-by: Richard Purdie <rpurdie@rpsys.net>
Cc: Russell King <rmk@arm.linux.org.uk>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
c72a1d608dd0eb3d553a08bfdf1c0041bebaa8a0 31-Mar-2006 Richard Purdie <rpurdie@rpsys.net> [PATCH] LED: add LED class

Add the foundations of a new LEDs subsystem. This patch adds a class which
presents LED devices within sysfs and allows their brightness to be
controlled.

Signed-off-by: Richard Purdie <rpurdie@rpsys.net>
Cc: Russell King <rmk@arm.linux.org.uk>
Cc: Greg KH <greg@kroah.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>