linux/include
Lyude Paul 867cf9cd73 drm/dp: Extract i915's eDP backlight code into DRM helpers
Since we're about to implement eDP backlight support in nouveau using the
standard protocol from VESA, we might as well just take the code that's
already written for this and move it into a set of shared DRM helpers.

Note that these helpers are intended to handle DPCD related backlight
control bits such as setting the brightness level over AUX, probing the
backlight's TCON, enabling/disabling the backlight over AUX if supported,
etc. Any PWM-related portions of backlight control are explicitly left up
to the driver, as these will vary from platform to platform.

The only exception to this is the calculation of the PWM frequency
pre-divider value. This is because the only platform-specific information
required for this is the PWM frequency of the panel, which the driver is
expected to provide if available. The actual algorithm for calculating this
value is standard and is defined in the eDP specification from VESA.

Note that these helpers do not yet implement the full range of features
the VESA backlight interface provides, and only provide the following
functionality (all of which was already present in i915's DPCD backlight
support):

* Basic control of brightness levels
* Basic probing of backlight capabilities
* Helpers for enabling and disabling the backlight

v3:
* Split out changes to i915's backlight code to separate patches to make it
  easier to review
v4:
* Style/spelling changes from Thomas Zimmermann
v5:
* Start using new drm_dbg_*() functions

Signed-off-by: Lyude Paul <lyude@redhat.com>
Cc: Jani Nikula <jani.nikula@intel.com>
Cc: Dave Airlie <airlied@gmail.com>
Cc: greg.depoire@gmail.com
Reviewed-by: Rodrigo Vivi <rodrigo.vivi@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20210514181504.565252-9-lyude@redhat.com
2021-06-09 13:35:22 -04:00
..
acpi
asm-generic mm: remove xlate_dev_kmem_ptr() 2021-05-07 00:26:34 -07:00
clocksource ARM: platform support for Apple M1 2021-04-26 12:30:36 -07:00
crypto
drm drm/dp: Extract i915's eDP backlight code into DRM helpers 2021-06-09 13:35:22 -04:00
dt-bindings Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/dtor/input 2021-05-06 23:37:55 -07:00
keys integrity-v5.13 2021-05-01 15:32:18 -07:00
kunit
kvm
linux dma-buf: drop the _rcu postfix on function names v3 2021-06-06 11:19:51 +02:00
math-emu
media media updates for v5.13-rc1 2021-04-28 09:24:36 -07:00
memory
misc
net mm: fix struct page layout on 32-bit systems 2021-05-14 19:41:32 -07:00
pcmcia
ras
rdma
scsi SCSI misc on 20210428 2021-04-28 17:22:10 -07:00
soc Networking changes for 5.13. 2021-04-29 11:57:23 -07:00
sound
target
trace NFS client updates for Linux 5.13 2021-05-07 11:23:41 -07:00
uapi drm/panfrost: Add AFBC_FEATURES parameter 2021-06-04 16:16:04 +01:00
vdso
video gpu: ipu-v3: Add Rec.709 limited range support to DP 2021-05-10 17:20:29 +02:00
xen xen/arm: move xen_swiotlb_detect to arm/swiotlb-xen.h 2021-05-14 15:52:05 +02:00