linux-toradex.git/include/linux/amba/clcd.h, branch v6.4-rc1

Partially revert "video: fbdev: amba-clcd: Retire elder CLCD driver"

2020-09-30T14:37:39+00:00

Also partially revert the follow-up change "drm: pl111: Absorb the
external register header".

This reverts the parts of commits
7e4e589db76a3cf4c1f534eb5a09cc6422766b93 and
0fb8125635e8eb5483fb095f98dcf0651206a7b8 that touch paths outside
of drivers/gpu/drm/pl111.

The fbdev driver is used by Android's FVP configuration. Using the
DRM driver together with DRM's fbdev emulation results in a failure
to boot Android. The root cause is that Android's generic fbdev
userspace driver relies on the ability to set the pixel format via
FBIOPUT_VSCREENINFO, which is not supported by fbdev emulation.

There have been other less critical behavioral differences identified
between the fbdev driver and the DRM driver with fbdev emulation. The
DRM driver exposes different values for the panel's width, height and
refresh rate, and the DRM driver fails a FBIOPUT_VSCREENINFO syscall
with yres_virtual greater than the maximum supported value instead
of letting the syscall succeed and setting yres_virtual based on yres.

Signed-off-by: Peter Collingbourne 
Signed-off-by: Daniel Vetter 
Link: https://patchwork.freedesktop.org/patch/msgid/20200929195344.2219796-1-pcc@google.com

video: fbdev: amba-clcd: Retire elder CLCD driver

2020-06-29T22:27:28+00:00

All the functionality in this driver has been reimplemented
in the new DRM driver in drivers/gpu/drm/pl111/* and all
the boards using it have been migrated to use the DRM driver
with all configuration coming from the device tree.

I started the work to migrate the CLCD driver to DRM in
april 2017 and it took a little more than 3 years to do this
properly without leaving any platforms behind.

Reviewed-by: Eric Anholt 
Signed-off-by: Linus Walleij 
Cc: Russell King 
Link: https://patchwork.freedesktop.org/patch/msgid/20200609200446.153209-2-linus.walleij@linaro.org

video: amba-clcd: Decomission Versatile and Nomadik

2019-04-11T17:25:12+00:00

These board families are now handled in the DRM subsystem
where we can have reusable panel drivers and some other
stuff. The PL111 there is now the driver used in the
defconfig for Versatile and Nomadik so no need to keep
this code around.

There are a few minor machines in arch/arm/ such as
mach-netx still using the old driver, so we need to keep
the core fbdev driver around for some time.

Signed-off-by: Linus Walleij 
Cc: Russell King 
Signed-off-by: Bartlomiej Zolnierkiewicz

video: ARM CLCD: Move registers to a separate header.

2017-05-08T19:24:06+00:00

We'd like to reuse these register definitions for the DRM CLCD driver,
but there's a bunch of fbdev-specific code in the current header.

v2: Add #ifndef guard.

Signed-off-by: Eric Anholt 
Link: http://patchwork.freedesktop.org/patch/msgid/20170413031746.12921-1-eric@anholt.net

video: ARM CLCD: support Nomadik variant

2016-08-11T14:54:53+00:00

The Nomadik variant has a few special quirks that need to be respected
to make the driver work:

- The block need to be clocked during writing of the TIMn registers
  or the bus will stall.
- Special bits in the control register select how many of the output
  display lines get activated.
- Special bits in the control register select how to manage the
  different 565 and 5551 modes.
- There is a packed 24bit graphics mode, i.e 888 pixels can be stored
  in memory is three consecutive bytes, not evenly aligned to a 32bit
  word.

This patch uses the vendor data pointer from the AMBA matching mechanism
to track the quirks for this variant, and adds two hooks that variants
can use to initialize boards and panels during start-up. These will
later be used to adopt a Nomadik board profile.

Cc: Pawel Moll 
Cc: Rob Herring 
Cc: Russell King 
Signed-off-by: Linus Walleij 
Signed-off-by: Tomi Valkeinen

video: ARM CLCD: support pads connected in reverse order

2016-08-11T14:54:53+00:00

There are CLCDs connected with the pads in BGR rather than RGB
order. It really doesn't matter since the CLCD has a flag and
a bit to switch the position of the RGB and BGR components.
This is needed to put something logical into the
arm,pl11x,tft-r0g0b0-pads property of the device tree on the
Nomadik which will then be <16 8 0>.

Cc: Pawel Moll 
Cc: Rob Herring 
Cc: Russell King 
Signed-off-by: Linus Walleij 
Signed-off-by: Tomi Valkeinen

video: ARM CLCD: backlight support for OF

2016-08-11T14:54:52+00:00

If the device is probed from device tree, we can support
backlight. This is used with some systems such as the
ST Microelectronics Nomadik.

We have to add HAS_IOMEM to the dependencies of CLCD since
the backlight class device will now be selected, and if it
gets selected on an arch that does not have IOMEM,
compilation will fail.

Cc: Pawel Moll 
Cc: Rob Herring 
Cc: Russell King 
Signed-off-by: Linus Walleij 
Signed-off-by: Tomi Valkeinen

Fix common misspellings

2011-03-31T14:26:23+00:00

Fixes generated by 'codespell' and manually reviewed.

Signed-off-by: Lucas De Marchi

ARM: clcd: add method for describing display capabilities

2011-02-19T11:09:05+00:00

The ARM CLCD PL110 controller in TFT mode provides two output formats
based on whether the controller is in 24bpp mode or not - either 5551
or 888.  PL111 augments this with a 444 and 565 modes.

Some implementations provide an external MUX on the PL110 output to
reassign the bits to achieve 565 mode.

Provide a system of capability flags to allow the CLCD driver to work
out what is supported by each panel and board, and therefore which
display formats are permitted.

Acked-by: Catalin Marinas 
Signed-off-by: Russell King

ARM: clcd: use amba_part() to determine if we have a PL110 primecell

2011-02-19T11:08:59+00:00

Instead of matching the entire peripheral ID, match against
just the part number using the amba_xxx() macros.

Acked-by: Catalin Marinas 
Signed-off-by: Russell King