linux-toradex.git/drivers, branch toradex_tk1_l4t_r21.6 Linux kernel for Apalis and Colibri modules apalis-tk1: handle backlight in the device tree 2018-03-28T16:40:19+00:00 Dominik Sliwa dominik.sliwa@toradex.com 2018-03-27T14:36:23+00:00 e81dd8a3500fea94ce8786554cbc29bc6b2a9207 Signed-off-by: Dominik Sliwa <dominik.sliwa@toradex.com> Acked-by: Marcel Ziswiler <marcel.ziswiler@toradex.com> 
Signed-off-by: Dominik Sliwa <dominik.sliwa@toradex.com>
Acked-by: Marcel Ziswiler <marcel.ziswiler@toradex.com>
pwm-backlight: Disable backlight on shutdown 2018-03-28T16:40:13+00:00 Thierry Reding treding@nvidia.com 2014-04-29T15:28:59+00:00 47be2c40872f5eebb568cc046e4ef145cfb1e0c7 When a device is shut down, make sure to disable the backlight. If it stays lit, it gives the impression that the device hasn't turned off. Furthermore keeping the backlight on may consume power, which is not what users expect when they shut down a device. Tested-by: Stephen Warren <swarren@nvidia.com> Signed-off-by: Thierry Reding <treding@nvidia.com> (cherry picked from commit 5f33b896246a2d9bdf01352de11d4dab96ba2fc9) 
When a device is shut down, make sure to disable the backlight. If it
stays lit, it gives the impression that the device hasn't turned off.
Furthermore keeping the backlight on may consume power, which is not
what users expect when they shut down a device.

Tested-by: Stephen Warren <swarren@nvidia.com>
Signed-off-by: Thierry Reding <treding@nvidia.com>
(cherry picked from commit 5f33b896246a2d9bdf01352de11d4dab96ba2fc9)
backlight: pwm_bl: Remove error message upon devm_kzalloc() failure 2018-03-28T16:40:11+00:00 Fabio Estevam fabio.estevam@freescale.com 2013-12-01T15:04:03+00:00 3a4920262b3fac01fa2b6f2b74859bc8feb92dad No need to have a specific OOM message, since there is generic MM out of memory message in place. Signed-off-by: Fabio Estevam <fabio.estevam@freescale.com> Signed-off-by: Thierry Reding <thierry.reding@gmail.com> (cherry picked from commit ca7a97add4d4a7b0602b3bd1eff5c89da8636713) 
No need to have a specific OOM message, since there is generic MM out of memory
message in place.

Signed-off-by: Fabio Estevam <fabio.estevam@freescale.com>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
(cherry picked from commit ca7a97add4d4a7b0602b3bd1eff5c89da8636713)
pwm-backlight: Remove unused variable 2018-03-28T16:40:07+00:00 Thierry Reding thierry.reding@gmail.com 2013-10-22T07:37:05+00:00 3ec7de5ab39db770ca65a30b0a3f7fdc789e7780 I forgot to remove this during earlier cleanup patches and only checked various builds for errors, not warnings. Reported-by: kbuild test robot <fengguang.wu@intel.com> Signed-off-by: Thierry Reding <thierry.reding@gmail.com> (cherry picked from commit 73d4e2b82b4bb1571b1a7f97012c0db8a0faef42) 
I forgot to remove this during earlier cleanup patches and only checked
various builds for errors, not warnings.

Reported-by: kbuild test robot <fengguang.wu@intel.com>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
(cherry picked from commit 73d4e2b82b4bb1571b1a7f97012c0db8a0faef42)
pwm_backlight: avoid short blank screen while doing hibernation 2018-03-28T16:40:04+00:00 Huayi Li huayi.li@csr.com 2013-10-09T02:33:02+00:00 c610794bd5f3b90231deb7daab8095821c6bee92 Use SIMPLE_DEV_PM_OPS macro will initialize the member "freeze" and "thaw" of pwm_backlight_pm_ops as below, .freeze = suspend_fn, .thaw = resume_fn, then during the process of making hibernation snapshot, screen will be blank at the moment of freezing, and then light at the moment of thawing. this is not the right user experience for suspending to disk. so this patch drops freeze and thaw callback, make the LCD is always lighting before the final shutdown. Signed-off-by: Huayi Li <huayi.li@csr.com> Signed-off-by: Barry Song <Baohua.Song@csr.com> Signed-off-by: Thierry Reding <thierry.reding@gmail.com> (cherry picked from commit 1dea1fd09246ada581a99d0669108eea94b7bfee) 
Use SIMPLE_DEV_PM_OPS macro will initialize the member "freeze"
and "thaw" of pwm_backlight_pm_ops as below,
	.freeze = suspend_fn,
	.thaw = resume_fn,
then during the process of making hibernation snapshot, screen
will be blank at the moment of freezing, and then light at the
moment of thawing.
this is not the right user experience for suspending to disk.

so this patch drops freeze and thaw callback, make the LCD is
always lighting before the final shutdown.

Signed-off-by: Huayi Li <huayi.li@csr.com>
Signed-off-by: Barry Song <Baohua.Song@csr.com>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
(cherry picked from commit 1dea1fd09246ada581a99d0669108eea94b7bfee)
pwm-backlight: Fix brightness adjustment 2018-03-28T16:40:01+00:00 Thierry Reding treding@nvidia.com 2013-10-18T08:46:24+00:00 8b58c9edccdbb58ec34df3a41375263a315db2c6 Split adjustment of the brightness (by changing the PWM duty cycle) from the power on sequence. This fixes an issue where the brightness can no longer be updated once the backlight has been enabled. Reported-by: Marc Dietrich <marvin24@gmx.de> Signed-off-by: Thierry Reding <treding@nvidia.com> (cherry picked from commit e4bfeda96872bfe6015cd360008b77cd3b981b2b) 
Split adjustment of the brightness (by changing the PWM duty cycle) from
the power on sequence. This fixes an issue where the brightness can no
longer be updated once the backlight has been enabled.

Reported-by: Marc Dietrich <marvin24@gmx.de>
Signed-off-by: Thierry Reding <treding@nvidia.com>
(cherry picked from commit e4bfeda96872bfe6015cd360008b77cd3b981b2b)
pwm-backlight: Allow for non-increasing brightness levels 2018-03-28T16:39:58+00:00 Mike Dunn mikedunn@newsguy.com 2013-09-22T16:59:56+00:00 d440decb0576ba222f3ee1f435afe9d7d9144214 Currently the driver assumes that the values specified in the brightness-levels device tree property increase as they are parsed from left to right. But boards that invert the signal between the PWM output and the backlight will need to specify decreasing brightness-levels. This patch removes the assumption that the last element of the array is the maximum value, and instead searches the array for the maximum value and uses that in the duty cycle calculation. Signed-off-by: Mike Dunn <mikedunn@newsguy.com> Signed-off-by: Thierry Reding <treding@nvidia.com> (cherry picked from commit 8f43e18e2769b3b28383903d501b4da29e388aad) 
Currently the driver assumes that the values specified in the
brightness-levels device tree property increase as they are parsed from
left to right.  But boards that invert the signal between the PWM output
and the backlight will need to specify decreasing brightness-levels.
This patch removes the assumption that the last element of the array is
the maximum value, and instead searches the array for the maximum value
and uses that in the duty cycle calculation.

Signed-off-by: Mike Dunn <mikedunn@newsguy.com>
Signed-off-by: Thierry Reding <treding@nvidia.com>
(cherry picked from commit 8f43e18e2769b3b28383903d501b4da29e388aad)
pwm-backlight: Add power supply support 2018-03-28T16:39:56+00:00 Thierry Reding treding@nvidia.com 2013-08-30T10:38:34+00:00 8ae5908bcb59f322456a000d97db397fe839dfe4 Backlights require a power supply to work properly. This commit adds a regulator to power up and power down the backlight. Signed-off-by: Thierry Reding <treding@nvidia.com> (cherry picked from commit 22ceeee16eb8f0d04de3ef43a5174fb30ec18af9) 
Backlights require a power supply to work properly. This commit adds a
regulator to power up and power down the backlight.

Signed-off-by: Thierry Reding <treding@nvidia.com>
(cherry picked from commit 22ceeee16eb8f0d04de3ef43a5174fb30ec18af9)
pwm-backlight: Use new enable_gpio field 2018-03-28T16:39:54+00:00 Thierry Reding treding@nvidia.com 2013-08-30T10:32:18+00:00 8431712fa81721de1e675d98f19d2de9ddc96195 Make use of the new enable_gpio field and allow it to be set from DT as well. Now that all legacy users of platform data have been converted to initialize this field to an invalid value, it is safe to use the field from the driver. Signed-off-by: Thierry Reding <treding@nvidia.com> (cherry picked from commit 8265b2e4e62632b01f998095d1bbda4d281629fe) 
Make use of the new enable_gpio field and allow it to be set from DT as
well. Now that all legacy users of platform data have been converted to
initialize this field to an invalid value, it is safe to use the field
from the driver.

Signed-off-by: Thierry Reding <treding@nvidia.com>
(cherry picked from commit 8265b2e4e62632b01f998095d1bbda4d281629fe)
pwm-backlight: Track enable state 2018-03-28T16:39:50+00:00 Thierry Reding treding@nvidia.com 2013-10-02T16:01:02+00:00 c3fb2cec492d1bd67c9204fc45f1e517e2fa4f53 Follow up patches will add support for more complex means of powering the backlight on and off such as using a regulator. To prevent calls to the regulator API from becoming unbalanced, keep track of the enabled state internally. Signed-off-by: Thierry Reding <treding@nvidia.com> (cherry picked from commit 97c38437115aa0c3fb2d50c488814b503ba529e0) 
Follow up patches will add support for more complex means of powering
the backlight on and off such as using a regulator. To prevent calls to
the regulator API from becoming unbalanced, keep track of the enabled
state internally.

Signed-off-by: Thierry Reding <treding@nvidia.com>
(cherry picked from commit 97c38437115aa0c3fb2d50c488814b503ba529e0)