linux/drivers/gpu/drm
Jani Nikula bc0bb9fd1c drm/i915: remove QUIRK_NO_PCH_PWM_ENABLE
The quirk was added as what I'd say was a stopgap measure in

commit e85843bec6
Author: Kamal Mostafa <kamal@canonical.com>
Date:   Fri Jul 19 15:02:01 2013 -0700

    drm/i915: quirk no PCH_PWM_ENABLE for Dell XPS13 backlight

without really digging into what was going on.

Also, as mentioned in the related bug [1], having the quirk regressed
some of the machines it was supposed to fix to begin with, and there
were patches posted to disable the quirk on such machines [2]!

The fact is, we do need the BLM_PCH_PWM_ENABLE bit set to have
backlight. With the quirk, we've relied on BIOS to have set it, and our
save/restore code to retain it. With the full backlight setup at enable,
we have no place for things that rely on previous state.

With the per platform hooks, we've also made a change in the PCH
platform enable order: setting the backlight duty cycle between CPU and
PCH PWM enable. Some experimenting and

commit 770c12312a
Author: Takashi Iwai <tiwai@suse.de>
Date:   Sat Aug 11 08:56:42 2012 +0200

    drm/i915: Fix blank panel at reopening lid

indicate that we can't set the backlight before enabling CPU PWM; the
value just won't stick. But AFAICT we should do it before enabling the
PCH PWM.

Finally, any fallout we should fix properly, preferrably without quirks,
and absolutely without quirks that rely on existing state. With the per
platform hooks have much more flexibility to adjust the sequence as
required by platforms.

[1] https://bugzilla.kernel.org/show_bug.cgi?id=47941
[2] http://lkml.kernel.org/r/1378229848-29113-1-git-send-email-kamal@canonical.com

Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Reviewed-by: Imre Deak <imre.deak@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2013-11-14 12:22:09 +01:00
..
armada DRM: Armada: convert to use simple_open() 2013-11-06 12:02:36 +10:00
ast drm: Add separate Kconfig option for fbdev helpers 2013-10-11 23:36:58 +02:00
cirrus drm/cirrus: use drm_set_preferred_mode 2013-11-06 13:36:19 +10:00
exynos drm: Add separate Kconfig option for fbdev helpers 2013-10-11 23:36:58 +02:00
gma500 drm/gma500/mrst: Add SDVO to output init 2013-11-08 16:23:19 +01:00
i2c drm/i2c: tda998x: set VIF for full range, underscanned display 2013-10-18 15:58:32 +01:00
i810 drm: Kill drm perf counter leftovers 2013-10-09 15:55:33 +10:00
i915 drm/i915: remove QUIRK_NO_PCH_PWM_ENABLE 2013-11-14 12:22:09 +01:00
mga drm: Kill drm perf counter leftovers 2013-10-09 15:55:33 +10:00
mgag200 drm/mgag200: drop pointless info print. 2013-11-08 15:49:43 +10:00
msm Merge branch 'msm-next' of git://people.freedesktop.org/~robclark/linux into drm-next 2013-11-10 18:27:31 +10:00
nouveau drm/nouveau: fix 32-bit build 2013-11-10 09:24:24 +10:00
omapdrm drm: Add separate Kconfig option for fbdev helpers 2013-10-11 23:36:58 +02:00
qxl qxl: add a connector property to denote hotplug should rescan modes. 2013-11-06 15:23:26 +10:00
r128
radeon Revert "drm/radeon/audio: don't set speaker allocation on DCE4+" 2013-11-08 13:07:51 -05:00
rcar-du drm: Add separate Kconfig option for fbdev helpers 2013-10-11 23:36:58 +02:00
savage
shmobile drm: shmob_drm: Convert to clk_prepare/unprepare 2013-11-10 18:48:38 +10:00
sis
tdfx
tegra drm/tegra: Changes for v3.13-rc1 2013-11-05 16:21:00 +10:00
tilcdc drm: Add separate Kconfig option for fbdev helpers 2013-10-11 23:36:58 +02:00
ttm Merge branch 'ttm-next-3.13' of git://people.freedesktop.org/~thomash/linux into drm-next 2013-11-07 12:22:10 +10:00
udl drm: Add separate Kconfig option for fbdev helpers 2013-10-11 23:36:58 +02:00
via drm: Kill ctx_count from struct drm_device 2013-10-09 15:55:32 +10:00
vmwgfx Merge tag 'drm-intel-fixes-2013-11-07' of git://people.freedesktop.org/~danvet/drm-intel into drm-next 2013-11-08 16:34:39 +10:00
ati_pcigart.c
drm_agpsupport.c
drm_auth.c
drm_buffer.c
drm_bufs.c
drm_cache.c
drm_context.c drm: Kill ctx_count from struct drm_device 2013-10-09 15:55:32 +10:00
drm_crtc_helper.c drm: eliminate bit-copy restoration of crtc 2013-11-06 14:27:51 +10:00
drm_crtc.c drm: Pretty print pixel format in drm_fb_get_bpp_depth() and format_check() 2013-11-06 13:29:34 +10:00
drm_debugfs.c drm: Make drm_debugfs_list const 2013-11-06 12:05:21 +10:00
drm_dma.c
drm_dp_helper.c drm/dp: constify DP DPCD helpers 2013-10-01 15:28:57 +10:00
drm_drv.c Merge tag 'drm-intel-fixes-2013-11-07' of git://people.freedesktop.org/~danvet/drm-intel into drm-next 2013-11-08 16:34:39 +10:00
drm_edid_load.c drm: Try loading builtin EDIDs first 2013-10-09 15:55:28 +10:00
drm_edid.c drm: add drm_set_preferred_mode 2013-11-06 13:36:18 +10:00
drm_encoder_slave.c
drm_fb_cma_helper.c
drm_fb_helper.c Merge tag 'v3.12' into drm-intel-next 2013-11-04 16:28:52 +01:00
drm_flip_work.c
drm_fops.c drm: Do not drop root privileges for a fancier younger process 2013-11-06 14:27:35 +10:00
drm_gem_cma_helper.c Merge branch 'drm-next' of git://people.freedesktop.org/~airlied/linux 2013-09-05 10:17:26 -07:00
drm_gem.c drm: kill ->gem_init_object() and friends 2013-10-09 14:38:02 +10:00
drm_global.c drm: Remove unused variable in drm_global_item_ref() 2013-10-01 15:28:58 +10:00
drm_hashtab.c
drm_info.c drm: Collect per-crtc vblank stuff to a struct 2013-10-09 15:55:31 +10:00
drm_ioc32.c
drm_ioctl.c drm: Add a STEREO_3D capability to the SET_CLIENT_CAP ioctl 2013-10-01 07:45:27 +02:00
drm_irq.c drm: Push latency sensitive bits of vblank scanoutpos timestamping into kms drivers. 2013-11-06 11:53:41 +10:00
drm_lock.c drm: Kill drm perf counter leftovers 2013-10-09 15:55:33 +10:00
drm_memory.c
drm_mm.c
drm_modes.c drm: copy mode type in drm_mode_connector_list_update() 2013-10-23 14:21:12 +01:00
drm_pci.c drm: Pass pointers to virt_to_page() 2013-11-06 13:23:20 +10:00
drm_platform.c drm: introduce drm_dev_free() to fix error paths 2013-10-09 15:55:09 +10:00
drm_prime.c drm: Remove unused variable in drm_prime_sg_to_page_addr_arrays() 2013-10-01 15:28:58 +10:00
drm_rect.c
drm_scatter.c
drm_stub.c drm: delay minor destruction to drm_dev_free() 2013-11-06 14:53:25 +10:00
drm_sysfs.c drm/sysfs: Remove stale comments about calling drm_sysfs_connector_add() multiple times 2013-11-06 13:41:37 +10:00
drm_trace_points.c
drm_trace.h
drm_usb.c drm: introduce drm_dev_free() to fix error paths 2013-10-09 15:55:09 +10:00
drm_vm.c drm: Pass pointers to virt_to_page() 2013-11-06 13:23:20 +10:00
drm_vma_manager.c
Kconfig drm/tegra: Changes for v3.13-rc1 2013-11-05 16:21:00 +10:00
Makefile drm/tegra: Changes for v3.13-rc1 2013-11-05 16:21:00 +10:00
README.drm

************************************************************
* For the very latest on DRI development, please see:      *
*     http://dri.freedesktop.org/                          *
************************************************************

The Direct Rendering Manager (drm) is a device-independent kernel-level
device driver that provides support for the XFree86 Direct Rendering
Infrastructure (DRI).

The DRM supports the Direct Rendering Infrastructure (DRI) in four major
ways:

    1. The DRM provides synchronized access to the graphics hardware via
       the use of an optimized two-tiered lock.

    2. The DRM enforces the DRI security policy for access to the graphics
       hardware by only allowing authenticated X11 clients access to
       restricted regions of memory.

    3. The DRM provides a generic DMA engine, complete with multiple
       queues and the ability to detect the need for an OpenGL context
       switch.

    4. The DRM is extensible via the use of small device-specific modules
       that rely extensively on the API exported by the DRM module.


Documentation on the DRI is available from:
    http://dri.freedesktop.org/wiki/Documentation
    http://sourceforge.net/project/showfiles.php?group_id=387
    http://dri.sourceforge.net/doc/

For specific information about kernel-level support, see:

    The Direct Rendering Manager, Kernel Support for the Direct Rendering
    Infrastructure
    http://dri.sourceforge.net/doc/drm_low_level.html

    Hardware Locking for the Direct Rendering Infrastructure
    http://dri.sourceforge.net/doc/hardware_locking_low_level.html

    A Security Analysis of the Direct Rendering Infrastructure
    http://dri.sourceforge.net/doc/security_low_level.html