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6 commits

Author SHA1 Message Date
Martin Pietryka
3d47b2d741 drivers/video/am335x-fb: Properly point framebuffer behind palette
The DMA was outputting the palette on the screen because the base
for the DMA was not after the palette. In addition to that, the ceiling was
also too high, this led that the output on the screen was shifted.

NOTE: According to the TRM, even in 16/24bit mode a palette is required
in the first 32 bytes of the framebuffer.

See also:
https://e2e.ti.com/support/arm/sitara_arm/f/791/p/234967/834483#834483

"In this mode, the LCDC will assume all information is data and thus you
need to ensure that the DMA points to the first pixel of data and not the
first entry in the frame buffer which is the beginning of the 512 byte
palette."

Signed-off-by: Martin Pietryka <martin.pietryka@chello.at>
Reviewed-by: Hannes Schmelzer <oe5hpm@oevsv.at>
Tested-by: Hannes Schmelzer <oe5hpm@oevsv.at>
2016-04-28 16:51:17 +02:00
Martin Pietryka
7d045170ac drivers/video/am335x-fb: Add support for 16bpp format
To support 16bpp we just need to change the raster_ctrl register
accordingly. Also 32bpp mode should work as well, but was not tested.
According to the TRM the uppermost byte will be ignored when
LCD_TFT_24BPP_UNPACK is set.

The switch logic is based on the Linux kernel tilcdc driver:
drivers/gpu/drm/tilcdc/tilcdc_crtc.c: lines 407 through 419
(kernel was checked out at commit: bcc981e9ed8)

Signed-off-by: Martin Pietryka <martin.pietryka@chello.at>
Reviewed-by: Hannes Schmelzer <oe5hpm@oevsv.at>
Tested-by: Hannes Schmelzer <oe5hpm@oevsv.at>
2016-04-28 16:50:52 +02:00
Martin Pietryka
ac5c61bfa6 drivers/video/am335x-fb: Fix bits for LCD_PALMODE_RAWDATA definition
According to the TRM you have to set bits [21:20] to 0b10 for RAW mode, so
(0x10 << 20) is obviously wrong here.

Signed-off-by: Martin Pietryka <martin.pietryka@chello.at>
2016-04-25 22:02:08 +02:00
Hannes Schmelzer
4c302b9a65 cosmetic: change Author/MAINTAINER Name from Petermaier to Schmelzer
Since i've been married, i also have a new surname.
Mr. Petermaier moved to Mr. Schmelzer.

In this patch i update all files in which my (old) name is present.

Signed-off-by: Hannes Schmelzer <hannes.schmelzer@br-automation.com>

Signed-off-by: Hannes Schmelzer <oe5hpm@oevsv.at>
2015-05-28 11:17:48 -04:00
Hannes Petermaier
3b4e16eb53 drivers/video/am335x-fb: Add possibility to wait for stable power/picture
Often on boards exists a circuit which switches power on/off to LCD display.
Due to the need of limiting the in-rush current the output voltage from this
circuit rises "slowly", so it is necessary to wait a bit (VCC ramp up time)
before starting output on LCD-pins.
This time is specified in <n> ms within the panel-settings, called "pup_delay"

Further some LCDs need a couple of frames to stabilize the image on it.
We have now the possibility to wait some time after starting output on LCD.
This time is also specified in <n> ms within panel-settings, called "pon_delay"

Signed-off-by: Hannes Petermaier <oe5hpm@oevsv.at>
2015-03-05 20:13:16 -05:00
Hannes Petermaier
3c5fabd139 video: Add support for TI's AM335x LCD-Controller
- Adds support for a minimal framebuffer driver of TI's AM335x SoC
  to be compatible with Wolfgang Denk's LCD-Framework (CONFIG_LCD,
  common/lcd.c)

Signed-off-by: Hannes Petermaier <oe5hpm@oevsv.at>
2014-08-10 15:34:27 +02:00