WSL2-Linux-Kernel/drivers/gpu/drm
Daniel Vetter 65e8186602 drm/i915: be more careful when returning -ENXIO in gmbus transfer
... flaky ddc hardware can cause a spurious NAK, resulting in the i2c
core and drm edid functions not trying to retry the edid transfer.

Luckily the gmbus quiescenting also times out for these cases, so we
can get out of this mess by returning -ETIMEDOUT for this specific
case. This way we keep the fast-fail of returning -ENXIO if there is
no device present, speeding up the boot process.

This regression has been introduced in

commit e646d57735
Author: Daniel Kurtz <djkurtz@chromium.org>
Date:   Fri Mar 30 19:46:38 2012 +0800

    drm/i915/intel_i2c: always wait for IDLE before clearing NAK

v2: Return -ETIMEDOUT for this case and keep the -ENXIO for real NAKs,
suggested by Daniel Kurtz.

Cc: Daniel Kurtz <djkurtz@chromium.org>
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=49518
Reported-and-Tested-by: Julian Simioni <julian.simioni@gmail.com>
Acked-by: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Daniel Kurtz <djkurtz@chromium.org>
Signed-Off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2012-05-21 21:04:21 +02:00
..
ast drm/kms: fix Kconfig for new drivers. 2012-05-20 10:10:53 +01:00
cirrus drm/kms: fix Kconfig for new drivers. 2012-05-20 10:10:53 +01:00
exynos Merge branch 'exynos-drm-fixes' of git://git.infradead.org/users/kmpark/linux-2.6-samsung into drm-fixes 2012-04-27 08:20:35 +01:00
gma500 gma500: fix build warning 2012-05-17 11:17:33 +01:00
i2c drm: add convenience function to create an range property 2012-02-09 10:15:25 +00:00
i810 kill mm argument of vm_munmap() 2012-04-21 01:58:20 -04:00
i915 drm/i915: be more careful when returning -ENXIO in gmbus transfer 2012-05-21 21:04:21 +02:00
mga drm: move pci bus master enable into driver. 2012-02-16 18:31:07 +00:00
mgag200 drm/kms: fix Kconfig for new drivers. 2012-05-20 10:10:53 +01:00
nouveau vga_switcheroo: Introduce struct vga_switcheroo_client_ops 2012-05-13 11:24:09 +02:00
r128 drm: move pci bus master enable into driver. 2012-02-16 18:31:07 +00:00
radeon drm/radeon/hdmi: use new AFMT structs 2012-05-17 12:16:03 +01:00
savage drm: checking the wrong variable in savage_do_init_bci() 2012-05-17 11:42:27 +01:00
sis drm: move pci bus master enable into driver. 2012-02-16 18:31:07 +00:00
tdfx
ttm Merge branch 'drm-next' of git://people.freedesktop.org/~airlied/linux 2012-03-22 13:08:22 -07:00
udl mm, drm/udl: fixup vma flags on mmap 2012-04-02 11:08:17 +01:00
via drm: move pci bus master enable into driver. 2012-02-16 18:31:07 +00:00
vmwgfx Merge branch 'drm-next' of git://people.freedesktop.org/~airlied/linux 2012-03-22 13:08:22 -07:00
Kconfig drm/kms: driver for virtual cirrus under qemu 2012-05-17 11:02:24 +01:00
Makefile drm/kms: driver for virtual cirrus under qemu 2012-05-17 11:02:24 +01:00
README.drm
ati_pcigart.c
drm_agpsupport.c
drm_auth.c drm: Fix authentication kernel crash 2012-01-25 09:27:45 +00:00
drm_buffer.c
drm_bufs.c VM: add "vm_mmap()" helper function 2012-04-20 17:29:13 -07:00
drm_cache.c Merge branch 'drm-intel-next' of git://people.freedesktop.org/~danvet/drm-intel into drm-core-next 2012-04-12 10:27:01 +01:00
drm_context.c drm: Unify and fix idr error handling 2012-04-24 09:50:20 +01:00
drm_crtc.c drm: add CRTC properties 2012-05-17 11:11:46 +01:00
drm_crtc_helper.c drm: Move drm_format_num_planes() to drm_crtc.c 2012-04-20 12:37:11 +01:00
drm_debugfs.c
drm_dma.c
drm_dp_i2c_helper.c
drm_drv.c drm: add generic ioctls to get/set properties on any object 2012-05-17 11:11:22 +01:00
drm_edid.c drm: Store vendor IDs directly in the EDID quirk structure 2012-04-27 08:25:13 +01:00
drm_edid_load.c drm/edid: fix collision between two patches breaking build 2012-04-30 07:26:16 +01:00
drm_edid_modes.h drm: replace open-coded ARRAY_SIZE with macro 2012-04-20 13:12:16 +01:00
drm_encoder_slave.c
drm_fb_helper.c drm/edid: Allow drm_mode_find_dmt to hunt for reduced-blanking modes 2012-04-20 12:57:03 +01:00
drm_fops.c drm: Releasing FBs before releasing GEM objects during drm_release 2012-04-19 14:40:41 +01:00
drm_gem.c drm: pass dev to drm_vm_{open,close}_locked() 2012-05-11 17:37:46 +01:00
drm_global.c
drm_hashtab.c
drm_info.c
drm_ioc32.c drivers/gpu/drm/drm_ioc32.c: initialize all fields 2012-02-03 09:47:32 +00:00
drm_ioctl.c drm/prime: expose capability flags for userspace. 2012-05-18 11:12:16 +01:00
drm_irq.c drm: remove unused code 2012-02-29 10:18:29 +00:00
drm_lock.c drm: add missing exports for i810 driver. 2011-12-22 19:09:01 +00:00
drm_memory.c drm: remove unused code 2012-02-29 10:18:29 +00:00
drm_mm.c
drm_modes.c drm: Add drm_mode_copy() 2012-03-15 09:52:51 +00:00
drm_pci.c drm: move pci bus master enable into driver. 2012-02-16 18:31:07 +00:00
drm_platform.c drm: cope with platformdev->id == -1 2012-03-07 14:03:40 +00:00
drm_prime.c drm: base prime/dma-buf support (v5) 2012-03-30 11:52:44 +01:00
drm_proc.c
drm_scatter.c
drm_stub.c drm: Unify and fix idr error handling 2012-04-24 09:50:20 +01:00
drm_sysfs.c drm/sysfs: protect sysfs removal code against being run twice. 2012-03-15 13:35:31 +00:00
drm_trace.h
drm_trace_points.c
drm_usb.c drm/usb: fix module license on drm/usb layer. 2012-04-19 09:33:32 +01:00
drm_vm.c drm: pass dev to drm_vm_{open,close}_locked() 2012-05-11 17:37:46 +01:00

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