Warn if we detect a panel with incomplete/wrong description.
This is inspired by a similar patch by Laurent that introduced checks
for LVDS panels - this extends the checks to the remaining type of
connectors.
This is known to warn for some of the existing panels but added
despite this as we need help from people using the panels to
add the missing info.
The checks are not complete but will catch the most common mistakes.
The checks at the same time serve as documentation for the minimum
required description for a panel.
The checks uses dev_warn() as we know this will hit. WARN() was
too noisy at the moment for anything else than LVDS.
v3:
- %d => %u for bpc (Laurent)
v2:
- Use dev_warn (Laurent)
- Check for empty bus_flags
Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Cc: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Cc: Thierry Reding <thierry.reding@gmail.com>
Cc: Sam Ravnborg <sam@ravnborg.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20200726203324.3722593-2-sam@ravnborg.org
On boe_nv133fhm_n62 (and presumably on boe_nv133fhm_n61) a scope shows
a small spike on the HPD line right when you power the panel on. The
picture looks something like this:
+--------------------------------------
|
|
|
Power ---+
+---
|
++ |
+----+| |
HPD -----+ +---------------------------+
So right when power is applied there's a little bump in HPD and then
there's small spike right before it goes low. The total time of the
little bump plus the spike was measured on one panel as being 8 ms
long. The total time for the HPD to go high on the same panel was
51.2 ms, though the datasheet only promises it is < 200 ms.
When asked about this glitch, BOE indicated that it was expected and
persisted until the TCON has been initialized.
If this was a real hotpluggable DP panel then this wouldn't matter a
whole lot. We'd debounce the HPD signal for a really long time and so
the little blip wouldn't hurt. However, this is not a hotpluggable DP
panel and the the debouncing logic isn't needed and just shows down
the time needed to get the display working. This is why the code in
panel_simple_prepare() doesn't do debouncing and just waits for HPD to
go high once. Unfortunately if we get unlucky and happen to poll the
HPD line right at the spike we can try talking to the panel before
it's ready.
Let's handle this situation by putting in a 15 ms prepare delay and
decreasing the "hpd absent delay" by 15 ms. That means:
* If you don't have HPD hooked up at all you've still got the
hardcoded 200 ms delay.
* If you've got HPD hooked up you will always wait at least 15 ms
before checking HPD. The only case where this could be bad is if
the panel is sharing a voltage rail with something else in the
system and was already turned on long before the panel came up. In
such a case we'll be delaying 15 ms for no reason, but it's not a
huge delay and I don't see any other good solution to handle that
case.
Even though the delay was measured as 8 ms, 15 ms was chosen to give a
bit of margin.
Signed-off-by: Douglas Anderson <dianders@chromium.org>
Reviewed-by: Bjorn Andersson <bjorn.andersson@linaro.org>
Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20200716132120.1.I01e738cd469b61fc9b28b3ef1c6541a4f48b11bf@changeid
The DRM panel bridge core requires connector type to be set up properly,
otherwise it rejects the panel. The missing connector type problem popped
up while I was trying to wrap CLAA070WP03XG panel into a DRM bridge in
order to test whether panel's rotation property work properly using
panel-simple driver on NVIDIA Tegra30 Nexus 7 tablet device, which uses
CLAA070WP03XG display panel.
The NVIDIA Tegra DRM driver recently gained DRM bridges support for the
RGB output and now driver wraps directly-connected panels into DRM bridge.
Hence all panels should have connector type set properly now, otherwise
the panel's wrapping fails.
This patch adds missing connector types for the LVDS panels that are found
on NVIDIA Tegra devices:
1. AUO B101AW03
2. Chunghwa CLAA070WP03XG
3. Chunghwa CLAA101WA01A
4. Chunghwa CLAA101WB01
5. EDT ET057090DHU
6. Innolux N156BGE L21
7. Samsung LTN101NT05
Signed-off-by: Dmitry Osipenko <digetx@gmail.com>
Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20200617222703.17080-8-digetx@gmail.com
People use panel-simple when they have panels that are builtin to
their device. In these cases the HPD (Hot Plug Detect) signal isn't
really used for hotplugging devices but instead is used for power
sequencing. Panel timing diagrams (especially for eDP panels) usually
have the HPD signal in them and it acts as an indicator that the panel
is ready for us to talk to it.
Sometimes the HPD signal is hooked up to a normal GPIO on a system.
In this case we need to poll it in the correct place to know that the
panel is ready for us. In some system designs the right place for
this is panel-simple.
When adding this support, we'll account for the case that there might
be a circular dependency between panel-simple and the provider of the
GPIO. The case this was designed for was for the "ti-sn65dsi86"
bridge chip. If HPD is hooked up to one of the GPIOs provided by the
bridge chip then in our probe function we'll always get back
-EPROBE_DEFER. Let's handle this by allowing this GPIO to show up
late if we saw -EPROBE_DEFER during probe. NOTE: since the
gpio_get_optional() is used, if the "hpd-gpios" isn't there our
variable will just be NULL and we won't do anything in prepare().
Signed-off-by: Douglas Anderson <dianders@chromium.org>
Reviewed-by: Stephen Boyd <swboyd@chromium.org>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20200507143354.v5.3.I53fed5b501a31e7a7fa13268ebcdd6b77bd0cadd@changeid
The BOE NV133FHM-N61 is documented in the original commit to be a
13.3" panel, but the size listed in our struct doesn't match.
Specifically:
math.sqrt(30.0 * 30.0 + 18.7 * 18.7) / 2.54 ==> 13.92
Searching around on the Internet shows that the size that was in the
structure was the "Outline Size", not the "Display Area". Let's fix
it.
Also the Internet says that this panel supports 262K colors. That's
6bpp, not 8bpp.
Fixes: b0c664cc80 ("panel: simple: Add BOE NV133FHM-N61")
Signed-off-by: Douglas Anderson <dianders@chromium.org>
Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20200508155859.1.I4d29651c0837b4095fb4951253f44036a371732f@changeid
The KR070PE2T is a 7" panel with a resolution of 800x480.
KR070PE2T is the marking present on the ribbon cable. As this panel is
probably available under different brands, this marking will catch
most devices.
As I can't find a datasheet for this panel, the bus_flags are instead
from trial-and-error. The flags seem to be common for these kind of
panels as well.
Signed-off-by: Pascal Roeleven <dev@pascalroeleven.nl>
Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20200320112205.7100-3-dev@pascalroeleven.nl
The currently listed dotclock disagrees with the currently
listed vrefresh rate. Change the dotclock to match the vrefresh.
There are two variants of the COM37H3M panel.
The older one's COM37H3M05DTC data sheet specifies:
MIN TYP MAX
CLK frequency fCLK -- 22.4 26.3 MHz (in VGA mode)
VSYNC Frequency fVSYNC 54 60 66 Hz
VSYNC cycle time tv -- 650 -- H
HSYNC frequency fHSYNC -- 39.3 -- kHz
HSYNC cycle time th -- 570 -- CLK
The newer one's COM37H3M99DTC data sheet says:
MIN TYP MAX
CLK frequency fCLK 18 19.8 27 MHz
VSYNC Frequency fVSYNC 54 60 66 Hz
VSYNC cycle time tv 646 650 700 H
HSYNC frequency fHSYNC -- 39.0 50.0 kHz
HSYNC cycle time th 504 508 630 CLK
So we choose a parameter set that lies within the specs
of both variants. We start at .vrefresh = 60,
choose .htotal = 570 and .vtotal = 650 and end up
in a clock of 22.230 MHz.
Reported-by: Ville Syrjala <ville.syrjala@linux.intel.com>
Signed-off-by: H. Nikolaus Schaller <hns@goldelico.com>
Reviewed-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
Link: https://patchwork.freedesktop.org/patch/msgid/e63a0533ad5b5142373437ef758aedbdb716152d.1583826198.git.hns@goldelico.com
The panel-dpi compatible is a fallback that
allows the DT to specify the timing.
When matching panel-dpi expect the device tree to include the
timing information for the display-panel.
Background for this change:
There are a lot of panels and new models hits the market very often.
It is a lost cause trying to chase them all and users of new panels
will often find them in situations that the panel they ues are not
supported by the kernel.
On top of this a lot of panels are customized based on customer
specifications.
Including the panel timing in the device tree allows for a simple
way to describe the actual HW and use this description in a generic
way in the kernel.
This allows uses of proprietary panels, or panels which are not
included in the kernel, to specify the timing in the device tree
together with all the other HW descriptions.
And thus, using the device tree it is then easy to add support
for an otherwise unknown panel.
The current support expect panels that do not require any
delays for prepare/enable/disable/unprepare.
Oleksandr Suvorov replied:
I've just tested this patch on Apalis iMX6Q and Colibri iMX7D using
panel settings from the following patch:
https://lore.kernel.org/linux-arm-kernel/20200115123401.2264293-4-oleksandr.suvorov@toradex.com/
It works for me, thanks!
Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
Reviewed-by: Oleksandr Suvorov <oleksandr.suvorov@toradex.com>
Tested-by: Oleksandr Suvorov <oleksandr.suvorov@toradex.com>
Acked-by: Maxime Ripard <mripard@kernel.org>
Cc: Thierry Reding <thierry.reding@gmail.com>
Cc: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Cc: Maxime Ripard <mripard@kernel.org>
Cc: Oleksandr Suvorov <oleksandr.suvorov@toradex.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200216181513.28109-6-sam@ravnborg.org
