Commit Graph

650 Commits

Author SHA1 Message Date
Thomas Gleixner
55716d2643 treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 428
Based on 1 normalized pattern(s):

  this file is released under the gplv2

extracted by the scancode license scanner the SPDX license identifier

  GPL-2.0-only

has been chosen to replace the boilerplate/reference in 68 file(s).

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Armijn Hemel <armijn@tjaldur.nl>
Reviewed-by: Allison Randal <allison@lohutok.net>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190531190114.292346262@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-06-05 17:37:16 +02:00
Thomas Gleixner
42bd2d91f3 treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 351
Based on 1 normalized pattern(s):

  this file is subject to the terms and conditions of the gnu general
  public license version 2 as published by the free software
  foundation

extracted by the scancode license scanner the SPDX license identifier

  GPL-2.0-only

has been chosen to replace the boilerplate/reference in 1 file(s).

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Armijn Hemel <armijn@tjaldur.nl>
Reviewed-by: Allison Randal <allison@lohutok.net>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190531081035.220801321@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-06-05 17:37:08 +02:00
Thomas Gleixner
4505153954 treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 333
Based on 1 normalized pattern(s):

  this program is free software you can redistribute it and or modify
  it under the terms of the gnu general public license version 2 as
  published by the free software foundation this program is
  distributed in the hope that it will be useful but without any
  warranty without even the implied warranty of merchantability or
  fitness for a particular purpose see the gnu general public license
  for more details you should have received a copy of the gnu general
  public license along with this program if not write to the free
  software foundation inc 59 temple place suite 330 boston ma 02111
  1307 usa

extracted by the scancode license scanner the SPDX license identifier

  GPL-2.0-only

has been chosen to replace the boilerplate/reference in 136 file(s).

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Alexios Zavras <alexios.zavras@intel.com>
Reviewed-by: Allison Randal <allison@lohutok.net>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190530000436.384967451@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-06-05 17:37:06 +02:00
Thomas Gleixner
c942fddf87 treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 157
Based on 3 normalized pattern(s):

  this program is free software you can redistribute it and or modify
  it under the terms of the gnu general public license as published by
  the free software foundation either version 2 of the license or at
  your option any later version this program is distributed in the
  hope that it will be useful but without any warranty without even
  the implied warranty of merchantability or fitness for a particular
  purpose see the gnu general public license for more details

  this program is free software you can redistribute it and or modify
  it under the terms of the gnu general public license as published by
  the free software foundation either version 2 of the license or at
  your option any later version [author] [kishon] [vijay] [abraham]
  [i] [kishon]@[ti] [com] this program is distributed in the hope that
  it will be useful but without any warranty without even the implied
  warranty of merchantability or fitness for a particular purpose see
  the gnu general public license for more details

  this program is free software you can redistribute it and or modify
  it under the terms of the gnu general public license as published by
  the free software foundation either version 2 of the license or at
  your option any later version [author] [graeme] [gregory]
  [gg]@[slimlogic] [co] [uk] [author] [kishon] [vijay] [abraham] [i]
  [kishon]@[ti] [com] [based] [on] [twl6030]_[usb] [c] [author] [hema]
  [hk] [hemahk]@[ti] [com] this program is distributed in the hope
  that it will be useful but without any warranty without even the
  implied warranty of merchantability or fitness for a particular
  purpose see the gnu general public license for more details

extracted by the scancode license scanner the SPDX license identifier

  GPL-2.0-or-later

has been chosen to replace the boilerplate/reference in 1105 file(s).

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Allison Randal <allison@lohutok.net>
Reviewed-by: Richard Fontana <rfontana@redhat.com>
Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190527070033.202006027@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-05-30 11:26:37 -07:00
Thomas Gleixner
1a59d1b8e0 treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 156
Based on 1 normalized pattern(s):

  this program is free software you can redistribute it and or modify
  it under the terms of the gnu general public license as published by
  the free software foundation either version 2 of the license or at
  your option any later version this program is distributed in the
  hope that it will be useful but without any warranty without even
  the implied warranty of merchantability or fitness for a particular
  purpose see the gnu general public license for more details you
  should have received a copy of the gnu general public license along
  with this program if not write to the free software foundation inc
  59 temple place suite 330 boston ma 02111 1307 usa

extracted by the scancode license scanner the SPDX license identifier

  GPL-2.0-or-later

has been chosen to replace the boilerplate/reference in 1334 file(s).

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Allison Randal <allison@lohutok.net>
Reviewed-by: Richard Fontana <rfontana@redhat.com>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190527070033.113240726@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-05-30 11:26:35 -07:00
Thomas Gleixner
2874c5fd28 treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 152
Based on 1 normalized pattern(s):

  this program is free software you can redistribute it and or modify
  it under the terms of the gnu general public license as published by
  the free software foundation either version 2 of the license or at
  your option any later version

extracted by the scancode license scanner the SPDX license identifier

  GPL-2.0-or-later

has been chosen to replace the boilerplate/reference in 3029 file(s).

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Allison Randal <allison@lohutok.net>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190527070032.746973796@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-05-30 11:26:32 -07:00
Thomas Gleixner
5e0f8ad07b treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 27
Based on 1 normalized pattern(s):

  this program is free software you can redistribute it and or modify
  it under the terms of the gnu general public license as published by
  the free software foundation either version 2 of the named license
  or any later version this program is distributed in the hope that it
  will be useful but without any warranty without even the implied
  warranty of merchantability or fitness for a particular purpose see
  the gnu general public license for more details you should have
  received a copy of the gnu general public license along with this
  program if not write to the free software foundation inc 59 temple
  place suite 330 boston ma 02111 1307 usa

extracted by the scancode license scanner the SPDX license identifier

  GPL-2.0-or-later

has been chosen to replace the boilerplate/reference in 7 file(s).

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Allison Randal <allison@lohutok.net>
Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190520170856.731149235@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-05-24 17:27:10 +02:00
Thomas Gleixner
1ccea77e2a treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 13
Based on 2 normalized pattern(s):

  this program is free software you can redistribute it and or modify
  it under the terms of the gnu general public license as published by
  the free software foundation either version 2 of the license or at
  your option any later version this program is distributed in the
  hope that it will be useful but without any warranty without even
  the implied warranty of merchantability or fitness for a particular
  purpose see the gnu general public license for more details you
  should have received a copy of the gnu general public license along
  with this program if not see http www gnu org licenses

  this program is free software you can redistribute it and or modify
  it under the terms of the gnu general public license as published by
  the free software foundation either version 2 of the license or at
  your option any later version this program is distributed in the
  hope that it will be useful but without any warranty without even
  the implied warranty of merchantability or fitness for a particular
  purpose see the gnu general public license for more details [based]
  [from] [clk] [highbank] [c] you should have received a copy of the
  gnu general public license along with this program if not see http
  www gnu org licenses

extracted by the scancode license scanner the SPDX license identifier

  GPL-2.0-or-later

has been chosen to replace the boilerplate/reference in 355 file(s).

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org>
Reviewed-by: Jilayne Lovejoy <opensource@jilayne.com>
Reviewed-by: Steve Winslow <swinslow@gmail.com>
Reviewed-by: Allison Randal <allison@lohutok.net>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190519154041.837383322@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-05-21 11:28:45 +02:00
Mikulas Patocka
babc250e27 udlfb: introduce a rendering mutex
Rendering calls may be done simultaneously from the workqueue,
dlfb_ops_write, dlfb_ops_ioctl, dlfb_ops_set_par and dlfb_dpy_deferred_io.
The code is robust enough so that it won't crash on concurrent rendering.

However, concurrent rendering may cause display corruption if the same
pixel is simultaneously being rendered. In order to avoid this corruption,
this patch adds a mutex around the rendering calls.

Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Cc: Bernie Thompson <bernie@plugable.com>
Cc: Ladislav Michl <ladis@linux-mips.org>
Cc: <stable@vger.kernel.org>
[b.zolnierkie: replace "dlfb:" with "uldfb:" in the patch summary]
Signed-off-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
2019-04-01 17:46:57 +02:00
Mikulas Patocka
6b11f9d843 udlfb: fix sleeping inside spinlock
If a framebuffer device is used as a console, the rendering calls
(copyarea, fillrect, imageblit) may be done with the console spinlock
held. On udlfb, these function call dlfb_handle_damage that takes a
blocking semaphore before acquiring an URB.

In order to fix the bug, this patch changes the calls copyarea, fillrect
and imageblit to offload USB work to a workqueue.

A side effect of this patch is 3x improvement in console scrolling speed
because the device doesn't have to be updated after each copyarea call.

Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Cc: Bernie Thompson <bernie@plugable.com>
Cc: Ladislav Michl <ladis@linux-mips.org>
Cc: <stable@vger.kernel.org>
Signed-off-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
2019-04-01 17:46:56 +02:00
Linus Torvalds
96a6de1a54 Merge tag 'media/v5.1-1' of git://git.kernel.org/pub/scm/linux/kernel/git/mchehab/linux-media
Pull media updates from Mauro Carvalho Chehab:

 - remove sensor drivers that got converted from soc_camera

 - remaining soc_camera drivers got moved to staging

 - some documentation cleanups and improvements

 - the imx staging driver now supports imx7

 - the ov9640, mt9m001 and mt9m111 got converted from soc_camera

 - the vim2m driver now does what a m2m convert driver expects to do

 - epoll() fixes on media subsystems

 - several drivers fixes, typos, cleanups and improvements

* tag 'media/v5.1-1' of git://git.kernel.org/pub/scm/linux/kernel/git/mchehab/linux-media: (346 commits)
  media: dvb/earth-pt1: fix wrong initialization for demod blocks
  media: vim2m: Address some coding style issues
  media: vim2m: don't use BUG()
  media: vim2m: speedup passthrough copy
  media: vim2m: add an horizontal scaler
  media: vim2m: don't accept YUYV anymore as output format
  media: vim2m: add vertical linear scaler
  media: vim2m: better handle cap/out buffers with different sizes
  media: vim2m: use different framesizes for bayer formats
  media: vim2m: add support for VIDIOC_ENUM_FRAMESIZES
  media: vim2m: ensure that width is multiple of two
  media: vim2m: improve debug messages
  media: vim2m: add bayer capture formats
  media: a few more typos at staging, pci, platform, radio and usb
  media: Documentation: fix several typos
  media: staging: fix several typos
  media: include: fix several typos
  media: common: fix several typos
  media: v4l2-core: fix several typos
  media: usb: fix several typos
  ...
2019-03-09 14:45:54 -08:00
Lucas Stach
4bfbd561fc gpu: ipu-v3: prg: add function to get channel configure status
This allows channels using the PRG to check if a requested configuration
update has been applied or is still pending.

Signed-off-by: Lucas Stach <l.stach@pengutronix.de>
[p.zabel@pengutronix.de: inverted logic: done -> pending]
Signed-off-by: Philipp Zabel <p.zabel@pengutronix.de>
2019-02-22 11:58:45 +01:00
Steve Longerbeam
9b5c8d5ffb media: gpu: ipu-v3: Add planar support to interlaced scan
To support interlaced scan with planar formats, cpmem SLUV must
be programmed with the correct chroma line stride. For full and
partial planar 4:2:2 (YUV422P, NV16), chroma line stride must
be doubled. For full and partial planar 4:2:0 (YUV420, YVU420, NV12),
chroma line stride must _not_ be doubled, since a single chroma line
is shared by two luma lines.

Signed-off-by: Steve Longerbeam <slongerbeam@gmail.com>
Reviewed-by: Philipp Zabel <p.zabel@pengutronix.de>
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
2019-01-16 14:12:20 -05:00
Steve Longerbeam
fc8c723852 media: gpu: ipu-csi: Swap fields according to input/output field types
The function ipu_csi_init_interface() was inverting the F-bit for
NTSC case, in the CCIR_CODE_1/2 registers. The result being that
for NTSC bottom-top field order, the CSI would swap fields and
capture in top-bottom order.

Instead, base field swap on the field order of the input to the CSI,
and the field order of the requested output. If the input/output
fields are sequential but different, swap fields, otherwise do
not swap. This requires passing both the input and output mbus
frame formats to ipu_csi_init_interface().

Move this code to a new private function ipu_csi_set_bt_interlaced_codes()
that programs the CCIR_CODE_1/2 registers for interlaced BT.656 (and
possibly interlaced BT.1120 in the future).

When detecting input video standard from the input frame width/height,
make sure to double height if input field type is alternate, since
in that case input height only includes lines for one field.

Signed-off-by: Steve Longerbeam <slongerbeam@gmail.com>
Reviewed-by: Philipp Zabel <p.zabel@pengutronix.de>
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
2019-01-16 14:11:42 -05:00
Christoph Manszewski
3b5129b3a7 drm/exynos: fimd: Make pixel blend mode configurable
The fimd hardware supports different blend modes. Add pixel blend mode
property and make it configurable, by modifying the blend equation.

Tested on TRATS2 with Exynos 4412 CPU, on top of linux-next-20181019.

Signed-off-by: Christoph Manszewski <c.manszewski@samsung.com>
Signed-off-by: Inki Dae <inki.dae@samsung.com>
2018-12-14 15:46:15 +09:00
Christoph Manszewski
6f8ee5c217 drm/exynos: fimd: Make plane alpha configurable
The fimd hardware supports variable plane alpha. Currently planes
are opaque, make this configurable.

Tested on TRATS2 with Exynos 4412 CPU, on top of linux-next-20181019.

Signed-off-by: Christoph Manszewski <c.manszewski@samsung.com>
Signed-off-by: Inki Dae <inki.dae@samsung.com>
2018-12-14 15:46:15 +09:00
Philipp Zabel
d0cbc93a01 gpu: ipu-v3: ipu-ic: allow to manually set resize coefficients
For tiled scaling, we want to compute the scaling coefficients
externally in such a way that the interpolation overshoots tile
boundaries and samples up to the first pixel of the next tile.
Prepare to override the resizing coefficients from the image
conversion code.

Signed-off-by: Philipp Zabel <p.zabel@pengutronix.de>
Acked-by: Steve Longerbeam <slongerbeam@gmail.com>
Tested-by: Steve Longerbeam <slongerbeam@gmail.com>
2018-11-05 14:40:06 +01:00
Steve Longerbeam
dec408fd23 gpu: ipu-v3: Add chroma plane offset overrides to ipu_cpmem_set_image()
Allow the caller of ipu_cpmem_set_image() to override the latters
calculation of the chroma plane offsets, by adding override U/V
plane offsets to 'struct ipu_image'.

Signed-off-by: Steve Longerbeam <slongerbeam@gmail.com>
Tested-by: Philipp Zabel <p.zabel@pengutronix.de>
Signed-off-by: Philipp Zabel <p.zabel@pengutronix.de>
2018-11-05 14:40:06 +01:00
Mikulas Patocka
68a958a915 udlfb: handle unplug properly
The udlfb driver maintained an open count and cleaned up itself when the
count reached zero. But the console is also counted in the reference count
- so, if the user unplugged the device, the open count would not drop to
zero and the driver stayed loaded with console attached. If the user
re-plugged the adapter, it would create a device /dev/fb1, show green
screen and the access to the console would be lost.

The framebuffer subsystem has reference counting on its own - in order to
fix the unplug bug, we rely the framebuffer reference counting. When the
user unplugs the adapter, we call unregister_framebuffer unconditionally.
unregister_framebuffer will unbind the console, wait until all users stop
using the framebuffer and then call the fb_destroy method. The fb_destroy
cleans up the USB driver.

This patch makes the following changes:
* Drop dlfb->kref and rely on implicit framebuffer reference counting
  instead.
* dlfb_usb_disconnect calls unregister_framebuffer, the rest of driver
  cleanup is done in the function dlfb_ops_destroy. dlfb_ops_destroy will
  be called by the framebuffer subsystem when no processes have the
  framebuffer open or mapped.
* We don't use workqueue during initialization, but initialize directly
  from dlfb_usb_probe. The workqueue could race with dlfb_usb_disconnect
  and this racing would produce various kinds of memory corruption.
* We use usb_get_dev and usb_put_dev to make sure that the USB subsystem
  doesn't free the device under us.

Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
cc: Dave Airlie <airlied@redhat.com>
Cc: Bernie Thompson <bernie@plugable.com>,
Cc: Ladislav Michl <ladis@linux-mips.org>
Signed-off-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
2018-10-08 12:57:34 +02:00
Linus Torvalds
06e386a1db Merge tag 'fbdev-v4.19' of https://github.com/bzolnier/linux
Pull fbdev updates from Bartlomiej Zolnierkiewicz:
 "Mostly small fixes and cleanups for fb drivers (the biggest updates
  are for udlfb and pxafb drivers). This also adds deferred console
  takeover support to the console code and efifb driver.

  Summary:

   - add support for deferred console takeover, when enabled defers
     fbcon taking over the console from the dummy console until the
     first text is displayed on the console - together with the "quiet"
     kernel commandline option this allows fbcon to still be used
     together with a smooth graphical bootup (Hans de Goede)

   - improve console locking debugging code (Thomas Zimmermann)

   - copy the ACPI BGRT boot graphics to the framebuffer when deferred
     console takeover support is used in efifb driver (Hans de Goede)

   - update udlfb driver - fix lost console when the user unplugs a USB
     adapter, fix the screen corruption issue, fix locking and add some
     performance optimizations (Mikulas Patocka)

   - update pxafb driver - fix using uninitialized memory, switch to
     devm_* API, handle initialization errors and add support for
     lcd-supply regulator (Daniel Mack)

   - add support for boards booted with a DeviceTree in pxa3xx_gcu
     driver (Daniel Mack)

   - rename omap2 module to omap2fb.ko to avoid conflicts with omap1
     driver (Arnd Bergmann)

   - enable ACPI-based enumeration for goldfishfb driver (Yu Ning)

   - fix goldfishfb driver to make user space Android code use 60 fps
     (Christoffer Dall)

   - print big fat warning when nomodeset kernel parameter is used in
     vgacon driver (Lyude Paul)

   - remove VLA usage from fsl-diu-fb driver (Kees Cook)

   - misc fixes (Julia Lawall, Geert Uytterhoeven, Fredrik Noring,
     Yisheng Xie, Dan Carpenter, Daniel Vetter, Anton Vasilyev, Randy
     Dunlap, Gustavo A. R. Silva, Colin Ian King, Fengguang Wu)

   - misc cleanups (Roman Kiryanov, Yisheng Xie, Colin Ian King)"

* tag 'fbdev-v4.19' of https://github.com/bzolnier/linux: (54 commits)
  Documentation/fb: corrections for fbcon.txt
  fbcon: Do not takeover the console from atomic context
  dummycon: Stop exporting dummycon_[un]register_output_notifier
  fbcon: Only defer console takeover if the current console driver is the dummycon
  fbcon: Only allow FRAMEBUFFER_CONSOLE_DEFERRED_TAKEOVER if fbdev is builtin
  fbdev: omap2: omapfb: fix ifnullfree.cocci warnings
  fbdev: omap2: omapfb: fix bugon.cocci warnings
  fbdev: omap2: omapfb: fix boolreturn.cocci warnings
  fb: amifb: fix build warnings when not builtin
  fbdev/core: Disable console-lock warnings when fb.lockless_register_fb is set
  console: Replace #if 0 with atomic var 'ignore_console_lock_warning'
  udlfb: use spin_lock_irq instead of spin_lock_irqsave
  udlfb: avoid prefetch
  udlfb: optimization - test the backing buffer
  udlfb: allow reallocating the framebuffer
  udlfb: set line_length in dlfb_ops_set_par
  udlfb: handle allocation failure
  udlfb: set optimal write delay
  udlfb: make a local copy of fb_ops
  udlfb: don't switch if we are switching to the same videomode
  ...
2018-08-23 15:44:58 -07:00
Mikulas Patocka
7433914efd udlfb: allow reallocating the framebuffer
This patch changes udlfb so that it may reallocate the framebuffer when
setting higher-resolution mode. If we boot the system without monitor
attached, udlfb creates a framebuffer with the size 800x600. This patch
makes it possible to select higher videomode with the fbset command when
a monitor is attached.

Note that there is no reliable way to prevent the system from touching the
old framebuffer, so we must not free it. We add it to the list
dlfb->deferred_free and free it when the driver is unloaded.

Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
[b.zolnierkie: sparse fixes]
Signed-off-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
2018-07-25 15:41:56 +02:00
Mikulas Patocka
bb24153a3f udlfb: set optimal write delay
The default delay 5 jiffies is too much when the kernel is compiled with
HZ=100 - it results in jumpy cursor in Xwindow.

In order to find out the optimal delay, I benchmarked the driver on
1280x720x30fps video. I found out that with HZ=1000, 10ms is acceptable,
but with HZ=250 or HZ=300, we need 4ms, so that the video is played
without any frame skips.

This patch changes the delay to this value.

Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Cc: stable@vger.kernel.org
Signed-off-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
2018-07-25 15:41:55 +02:00
Mikulas Patocka
2c29cfc3ea udlfb: make a local copy of fb_ops
The defio subsystem overwrites the method fb_osp->mmap. That method is
stored in module's static data - and that means that if we have multiple
diplaylink adapters, they will over write each other's method.

In order to avoid interference between multiple adapters, we copy the
fb_ops structure to a device-local memory.

Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Cc: stable@vger.kernel.org
Signed-off-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
2018-07-25 15:41:55 +02:00
Mikulas Patocka
564f180737 udlfb: don't switch if we are switching to the same videomode
The udlfb driver reprograms the hardware everytime the user switches the
console, that makes quite unusable when working on the console.

This patch makes the driver remember the videomode we are in and avoid
reprogramming the hardware if we switch to the same videomode.

We mask the "activate" field and the "FB_VMODE_SMOOTH_XPAN" flag when
comparing the videomode, because they cause spurious switches when
switching to and from the Xserver.

Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Cc: stable@vger.kernel.org
Signed-off-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
2018-07-25 15:41:55 +02:00
Mikulas Patocka
9d0aa601e4 udlfb: fix semaphore value leak
I observed that the performance of the udl fb driver degrades over time.
On a freshly booted machine, it takes 6 seconds to do "ls -la /usr/bin";
after some time of use, the same operation takes 14 seconds.

The reason is that the value of "limit_sem" decays over time.

The udl driver uses a semaphore "limit_set" to specify how many free urbs
are there on dlfb->urbs.list. If the count is zero, the "down" operation
will sleep until some urbs are added to the freelist.

In order to avoid some hypothetical deadlock, the driver will not call
"up" immediately, but it will offload it to a workqueue. The problem is
that if we call "schedule_delayed_work" on the same work item multiple
times, the work item may only be executed once.

This is happening:
* some urb completes
* dlfb_urb_completion adds it to the free list
* dlfb_urb_completion calls schedule_delayed_work to schedule the function
  dlfb_release_urb_work to increase the semaphore count
* as the urb is on the free list, some other task grabs it and submits it
* the submitted urb completes, dlfb_urb_completion is called again
* dlfb_urb_completion calls schedule_delayed_work, but the work is already
  scheduled, so it does nothing
* finally, dlfb_release_urb_work is called, it increases the semaphore
  count by 1, although it should increase it by 2

So, the semaphore count is decreasing over time, and this causes gradual
performance degradation.

Note that in the current kernel, the "up" function may be called from
interrupt and it may race with the "down" function called by another
thread, so we don't have to offload the call of "up" to a workqueue at
all. This patch removes the workqueue code. The patch also changes
"down_interruptible" to "down" in dlfb_free_urb_list, so that we will
clean up the driver properly even if a signal arrives.

With this patch, the performance of udlfb no longer degrades.

Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Cc: stable@vger.kernel.org
[b.zolnierkie: fix immediatelly -> immediately typo]
Signed-off-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
2018-07-25 15:41:54 +02:00