ti-sn65dsi86 bridge is enumerated as a runtime device. When
suspend is triggered, PM core adds a refcount on all the
devices and calls device suspend, since usage count is
already incremented, runtime suspend will not be called
and it kept the bridge regulators and gpios ON which resulted
in platform not entering into XO shutdown.
Add changes to force suspend on the runtime device during pm sleep.
Signed-off-by: Harigovindan P <harigovi@codeaurora.org>
Reviewed-by: Stephen Boyd <swboyd@chromium.org>
Reviewed-by: Douglas Anderson <dianders@chromium.org>
Signed-off-by: Neil Armstrong <narmstrong@baylibre.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200609120455.20458-1-harigovi@codeaurora.org
The ti_sn_bridge_gpio_set() got the return value of
regmap_update_bits() but didn't check it. The function can't return
an error value, but we should at least print a warning if it didn't
work.
This fixes a compiler warning about setting "ret" but not using it.
Fixes: 27ed2b3f22 ("drm/bridge: ti-sn65dsi86: Export bridge GPIOs to Linux")
Signed-off-by: Douglas Anderson <dianders@chromium.org>
Reviewed-by: Stephen Boyd <swboyd@chromium.org>
Signed-off-by: Neil Armstrong <narmstrong@baylibre.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200612123003.v2.4.Ia4376fd88cdc6e8f8b43c65548458305f82f1d61@changeid
When building we were getting an error:
warning: cannot understand function prototype:
'const unsigned int ti_sn_bridge_dp_rate_lut[] = '
Arrays aren't supposed to be marked with "/**" kerneldoc comments. Fix.
Fixes: a095f15c00 ("drm/bridge: add support for sn65dsi86 bridge driver")
Signed-off-by: Douglas Anderson <dianders@chromium.org>
Reviewed-by: Stephen Boyd <swboyd@chromium.org>
Signed-off-by: Neil Armstrong <narmstrong@baylibre.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200612123003.v2.2.If3807e4ebf7f0440f64c3069edcfac9a70171940@changeid
The kernel test robot noted that if "OF" is defined (which is needed
to select DRM_TI_SN65DSI86 at all) but not OF_GPIO that we'd get
compile failures because some of the members that we access in "struct
gpio_chip" are only defined "#if defined(CONFIG_OF_GPIO)".
All the GPIO bits in the driver are all nicely separated out. We'll
guard them with the same "#if defined" that the header has and add a
little stub function if OF_GPIO is not defined.
Fixes: 27ed2b3f22 ("drm/bridge: ti-sn65dsi86: Export bridge GPIOs to Linux")
Reported-by: kernel test robot <lkp@intel.com>
Signed-off-by: Douglas Anderson <dianders@chromium.org>
Reviewed-by: Stephen Boyd <swboyd@chromium.org>
Signed-off-by: Neil Armstrong <narmstrong@baylibre.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200612123003.v2.1.Ibe95d8f3daef01e5c57d4c8c398f04d6a839492c@changeid
The ti-sn65dsi86 MIPI DSI to eDP bridge chip supports arbitrary
remapping of eDP lanes and also polarity inversion. Both of these
features have been described in the device tree bindings for the
device since the beginning but were never implemented in the driver.
Implement both of them.
Part of this change also allows you to (via the same device tree
bindings) specify to use fewer than the max number of DP lanes that
the panel reports. This could be useful if your display supports more
lanes but only a few are hooked up on your board.
Signed-off-by: Douglas Anderson <dianders@chromium.org>
Reviewed-by: Stephen Boyd <swboyd@chromium.org>
Reviewed-by: Rob Clark <robdclark@gmail.com>
Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20200518114656.REPOST.v2.1.Ibc8eeddcee94984a608d6900b46f9ffde4045da4@changeid
If the rate in our table is _equal_ to the rate we want then it's OK
to pick it. It doesn't need to be greater than the one we want.
Fixes: a095f15c00 ("drm/bridge: add support for sn65dsi86 bridge driver")
Signed-off-by: Douglas Anderson <dianders@chromium.org>
Reviewed-by: Stephen Boyd <swboyd@chromium.org>
Reviewed-by: Rob Clark <robdclark@gmail.com>
Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20200504213225.1.I21646c7c37ff63f52ae6cdccc9bc829fbc3d9424@changeid
The AUX channel transfer error bits in the status register are latched
and need to be cleared. Clear them before doing our transfer so we
don't see old bits and get confused.
Without this patch having a single failure would mean that all future
transfers would look like they failed.
Fixes: b814ec6d45 ("drm/bridge: ti-sn65dsi86: Implement AUX channel")
Signed-off-by: Douglas Anderson <dianders@chromium.org>
Reviewed-by: Rob Clark <robdclark@gmail.com>
Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20200508163314.1.Idfa69d5d3fc9623083c0ff78572fea87dccb199c@changeid
The ti-sn65dsi86 MIPI DSI to eDP bridge chip has 4 pins on it that can
be used as GPIOs in a system. Each pin can be configured as input,
output, or a special function for the bridge chip. These are:
- GPIO1: SUSPEND Input
- GPIO2: DSIA VSYNC
- GPIO3: DSIA HSYNC or VSYNC
- GPIO4: PWM
Let's expose these pins as GPIOs. A few notes:
- Access to ti-sn65dsi86 is via i2c so we set "can_sleep".
- These pins can't be configured for IRQ.
- There are no programmable pulls or other fancy features.
- Keeping the bridge chip powered might be expensive. The driver is
setup such that if all used GPIOs are only inputs we'll power the
bridge chip on just long enough to read the GPIO and then power it
off again. Setting a GPIO as output will keep the bridge powered.
- If someone releases a GPIO we'll implicitly switch it to an input so
we no longer need to keep the bridge powered for it.
Because of all of the above limitations we just need to implement a
bare-bones GPIO driver. The device tree bindings already account for
this device being a GPIO controller so we only need the driver changes
for it.
NOTE: Despite the fact that these pins are nominally muxable I don't
believe it makes sense to expose them through the pinctrl interface as
well as the GPIO interface. The special functions are things that the
bridge chip driver itself would care about and it can just configure
the pins as needed.
Signed-off-by: Douglas Anderson <dianders@chromium.org>
Reviewed-by: Stephen Boyd <swboyd@chromium.org>
Reviewed-by: Bjorn Andersson <bjorn.andersson@linaro.org>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
[added pdata->gchip.base = -1;]
Cc: Linus Walleij <linus.walleij@linaro.org>
Cc: Bartosz Golaszewski <bgolaszewski@baylibre.com>
Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20200507143354.v5.1.Ia50267a5549392af8b37e67092ca653a59c95886@changeid
Most bridge drivers create a DRM connector to model the connector at the
output of the bridge. This model is historical and has worked pretty
well so far, but causes several issues:
- It prevents supporting more complex display pipelines where DRM
connector operations are split over multiple components. For instance a
pipeline with a bridge connected to the DDC signals to read EDID data,
and another one connected to the HPD signal to detect connection and
disconnection, will not be possible to support through this model.
- It requires every bridge driver to implement similar connector
handling code, resulting in code duplication.
- It assumes that a bridge will either be wired to a connector or to
another bridge, but doesn't support bridges that can be used in both
positions very well (although there is some ad-hoc support for this in
the analogix_dp bridge driver).
In order to solve these issues, ownership of the connector should be
moved to the display controller driver (where it can be implemented
using helpers provided by the core).
Extend the bridge API to allow disabling connector creation in bridge
drivers as a first step towards the new model. The new flags argument to
the bridge .attach() operation allows instructing the bridge driver to
skip creating a connector. Unconditionally set the new flags argument to
0 for now to keep the existing behaviour, and modify all existing bridge
drivers to return an error when connector creation is not requested as
they don't support this feature yet.
The change is based on the following semantic patch, with manual review
and edits.
@ rule1 @
identifier funcs;
identifier fn;
@@
struct drm_bridge_funcs funcs = {
...,
.attach = fn
};
@ depends on rule1 @
identifier rule1.fn;
identifier bridge;
statement S, S1;
@@
int fn(
struct drm_bridge *bridge
+ , enum drm_bridge_attach_flags flags
)
{
... when != S
+ if (flags & DRM_BRIDGE_ATTACH_NO_CONNECTOR) {
+ DRM_ERROR("Fix bridge driver to make connector optional!");
+ return -EINVAL;
+ }
+
S1
...
}
@ depends on rule1 @
identifier rule1.fn;
identifier bridge, flags;
expression E1, E2, E3;
@@
int fn(
struct drm_bridge *bridge,
enum drm_bridge_attach_flags flags
) {
<...
drm_bridge_attach(E1, E2, E3
+ , flags
)
...>
}
@@
expression E1, E2, E3;
@@
drm_bridge_attach(E1, E2, E3
+ , 0
)
Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Reviewed-by: Boris Brezillon <boris.brezillon@collabora.com>
Acked-by: Sam Ravnborg <sam@ravnborg.org>
Reviewed-by: Tomi Valkeinen <tomi.valkeinen@ti.com>
Tested-by: Sebastian Reichel <sebastian.reichel@collabora.com>
Reviewed-by: Sebastian Reichel <sebastian.reichel@collabora.com>
Acked-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Tomi Valkeinen <tomi.valkeinen@ti.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200226112514.12455-10-laurent.pinchart@ideasonboard.com
Based on work by Bjorn Andersson <bjorn.andersson@linaro.org>,
Jeffrey Hugo <jeffrey.l.hugo@gmail.com>, and
Rob Clark <robdclark@chromium.org>.
Let's read the SUPPORTED_LINK_RATES and/or MAX_LINK_RATE (depending on
the eDP version of the sink) to figure out what eDP rates are
supported and pick the ideal one.
NOTE: I have only personally tested this code on eDP panels that are
1.3 or older. Code reading SUPPORTED_LINK_RATES for DP 1.4+ was
tested by hacking the code to pretend that a table was there.
Signed-off-by: Douglas Anderson <dianders@chromium.org>
Reviewed-by: Bjorn Andersson <bjorn.andersson@linaro.org>
Signed-off-by: Neil Armstrong <narmstrong@baylibre.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20191218143416.v3.9.Ib59207b66db377380d13748752d6fce5596462c5@changeid
If we fail training at a lower DP link rate let's now keep trying
until we run out of rates to try. Basically the algorithm here is to
start at the link rate that is the theoretical minimum and then slowly
bump up until we run out of rates or hit the max rate of the sink. We
query the sink using a DPCD read.
This is, in fact, important in practice. Specifically at least one
panel hooked up to the bridge (AUO B116XAK01) had a theoretical min
rate more than 1.62 GHz (if run at 24 bpp) and fails to train at the
next rate (2.16 GHz). It would train at 2.7 GHz, though.
Signed-off-by: Douglas Anderson <dianders@chromium.org>
Tested-by: Rob Clark <robdclark@gmail.com>
Reviewed-by: Rob Clark <robdclark@gmail.com>
Reviewed-by: Bjorn Andersson <bjorn.andersson@linaro.org>
Signed-off-by: Neil Armstrong <narmstrong@baylibre.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20191218143416.v3.8.I251add713bc5c97225200894ab110ea9183434fd@changeid
We'll re-organize the ti_sn_bridge_enable() function a bit to group
together all the parts relating to link training and split them into a
sub-function. This is not intended to have any functional change and
is in preparation for trying link training several times at different
rates. One small side effect here is that if link training fails
we'll now leave the DP PLL disabled, but that seems like a sane thing
to do.
Signed-off-by: Douglas Anderson <dianders@chromium.org>
Tested-by: Rob Clark <robdclark@gmail.com>
Reviewed-by: Rob Clark <robdclark@gmail.com>
Reviewed-by: Bjorn Andersson <bjorn.andersson@linaro.org>
Signed-off-by: Neil Armstrong <narmstrong@baylibre.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20191218143416.v3.7.I1fc75ad11db9048ef08cfe1ab7322753d9a219c7@changeid
The current bridge driver always forced us to use 24 bits per pixel
over the DP link. This is a waste if you are hooked up to a panel
that only supports 6 bits per color or fewer, since in that case you
can run at 18 bits per pixel and thus end up at a lower DP clock rate.
Let's support this.
While at it, let's clean up the math in the function to avoid rounding
errors (and round in the correct direction when we have to round).
Numbers are sufficiently small (because mode->clock is in kHz) that we
don't need to worry about integer overflow.
Signed-off-by: Douglas Anderson <dianders@chromium.org>
Tested-by: Rob Clark <robdclark@gmail.com>
Reviewed-by: Rob Clark <robdclark@gmail.com>
Reviewed-by: Bjorn Andersson <bjorn.andersson@linaro.org>
[narmstrong: s/ran/can/]
Signed-off-by: Neil Armstrong <narmstrong@baylibre.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20191218143416.v3.6.Iaf8d698f4e5253d658ae283d2fd07268076a7c27@changeid
At least one panel hooked up to the bridge (AUO B116XAK01) only
supports 1 lane of DP. Let's read this information and stop
hardcoding 4 DP lanes.
Signed-off-by: Douglas Anderson <dianders@chromium.org>
Tested-by: Rob Clark <robdclark@gmail.com>
Reviewed-by: Rob Clark <robdclark@gmail.com>
Reviewed-by: Bjorn Andersson <bjorn.andersson@linaro.org>
Signed-off-by: Neil Armstrong <narmstrong@baylibre.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20191218143416.v3.5.Idbd0051d0de53f7e9d18a291ea33011c0854fcc6@changeid
The driver used to say that the value to program into bridge register
0x93 was dp_lanes - 1. Looking at the datasheet for the bridge, this
is wrong. The data sheet says:
* 1 = 1 lane
* 2 = 2 lanes
* 3 = 4 lanes
A more proper way to express this encoding is min(dp_lanes, 3).
At the moment this change has zero effect because we've hardcoded the
number of DP lanes to 4. ...and (4 - 1) == min(4, 3). How fortunate!
...but soon we'll stop hardcoding the number of lanes.
Signed-off-by: Douglas Anderson <dianders@chromium.org>
Tested-by: Rob Clark <robdclark@gmail.com>
Reviewed-by: Rob Clark <robdclark@gmail.com>
Reviewed-by: Bjorn Andersson <bjorn.andersson@linaro.org>
Signed-off-by: Neil Armstrong <narmstrong@baylibre.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20191218143416.v3.4.If3e2d0493e7b6e8b510ea90d8724ff760379b3ba@changeid
The ti-sn65dsi86 is a bridge from MIPI to DP and thus has two links:
the MIPI link and the DP link. The two links do not need to have the
same format or number of lanes. Stop using MIPI variables when
talking about the DP link.
This has zero functional change because:
* currently we are hardcoding the MIPI link as unpacked RGB888 which
requires 24 bits and currently we are not changing the DP link rate
from the bridge's default of 8 bits per pixel.
* currently we are hardcoding both the MIPI and DP as being 4 lanes.
This is all in prep for fixing some of the above.
Signed-off-by: Douglas Anderson <dianders@chromium.org>
Tested-by: Rob Clark <robdclark@gmail.com>
Reviewed-by: Rob Clark <robdclark@gmail.com>
Reviewed-by: Bjorn Andersson <bjorn.andersson@linaro.org>
Signed-off-by: Neil Armstrong <narmstrong@baylibre.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20191218143416.v3.3.Ia6e05f4961adb0d4a0d32ba769dd7781ee8db431@changeid
When we iterate over ti_sn_bridge_dp_rate_lut, there's no reason to
start at index 0 which always contains the value 0. 0 is not a valid
link rate.
This change should have no real effect but is a small cleanup.
Signed-off-by: Douglas Anderson <dianders@chromium.org>
Tested-by: Rob Clark <robdclark@gmail.com>
Reviewed-by: Rob Clark <robdclark@gmail.com>
Reviewed-by: Bjorn Andersson <bjorn.andersson@linaro.org>
Signed-off-by: Neil Armstrong <narmstrong@baylibre.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20191218143416.v3.2.Id445d0057bedcb0a190009e0706e9254c2fd48eb@changeid
These two things were in one function. Split into two. This looks
like it's duplicating some code, but don't worry. This is is just in
preparation for future changes.
This is intended to have zero functional change and will just make
future patches easier to understand.
Signed-off-by: Douglas Anderson <dianders@chromium.org>
Tested-by: Rob Clark <robdclark@gmail.com>
Reviewed-by: Rob Clark <robdclark@gmail.com>
Reviewed-by: Bjorn Andersson <bjorn.andersson@linaro.org>
Signed-off-by: Neil Armstrong <narmstrong@baylibre.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20191218143416.v3.1.Icb765d5799e9651e5249c0c27627ba33a9e411cf@changeid
We are about to add a drm_bridge_state that inherits from
drm_private_state which is defined in drm_atomic.h. Problem is,
drm_atomic.h includes drm_crtc.h which in turn includes drm_bridge.h,
leading to "drm_private_state has incomplete type" error.
Let's force all users of the drm_bridge API to explicitly include
drm_bridge.h.
Signed-off-by: Boris Brezillon <boris.brezillon@collabora.com>
Reviewed-by: Sam Ravnborg <sam@ravnborg.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20190826152649.13820-2-boris.brezillon@collabora.com
This should be more future-proof if we ever encounter a device with two
of these bridges.
Suggested-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Rob Clark <robdclark@chromium.org>
Reviewed-by: Bjorn Andersson <bjorn.andersson@linaro.org>
Signed-off-by: Andrzej Hajda <a.hajda@samsung.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20190706203105.7810-1-robdclark@gmail.com
Noticed while comparing register dump of how bootloader configures DSI
vs how kernel configures. It seems the bridge still works either way,
but fixing this clears the 'CHA_DATATYPE_ERR' error status bit.
Signed-off-by: Rob Clark <robdclark@chromium.org>
Reviewed-by: Jeffrey Hugo <jeffrey.l.hugo@gmail.com>
Reviewed-by: Andrzej Hajda <a.hajda@samsung.com>
Signed-off-by: Andrzej Hajda <a.hajda@samsung.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20190702154419.20812-4-robdclark@gmail.com
The bridge has pretty good docs, lets add a link to make them easier to
find.
Signed-off-by: Rob Clark <robdclark@chromium.org>
Reviewed-by: Jeffrey Hugo <jeffrey.l.hugo@gmail.com>
Reviewed-by: Andrzej Hajda <a.hajda@samsung.com>
Signed-off-by: Andrzej Hajda <a.hajda@samsung.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20190702154419.20812-2-robdclark@gmail.com
Drop use of the deprecated drmP.h header file.
While touching the list of include files:
- Divide include files in blocks of linux/* drm/* etc.
- Sort individual blocks of include files
- Remove duplicated header file
v2:
- Be consistent in the order of the include blocks (Laurent)
Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
Reviewed-by: Laurent Pinchart <Laurent.pinchart@ideasonboard.com>
Cc: Andrzej Hajda <a.hajda@samsung.com>
Cc: David Airlie <airlied@linux.ie>
Cc: Daniel Vetter <daniel@ffwll.ch>
Cc: Peter Senna Tschudin <peter.senna@gmail.com>
Cc: Martin Donnelly <martin.donnelly@ge.com>
Cc: Martyn Welch <martyn.welch@collabora.co.uk>
Link: https://patchwork.freedesktop.org/patch/msgid/20190519183636.19588-1-sam@ravnborg.org
Having the probe helper stuff (which pretty much everyone needs) in
the drm_crtc_helper.h file (which atomic drivers should never need) is
confusing. Split them out.
To make sure I actually achieved the goal here I went through all
drivers. And indeed, all atomic drivers are now free of
drm_crtc_helper.h includes.
v2: Make it compile. There was so much compile fail on arm drivers
that I figured I'll better not include any of the acks on v1.
v3: Massive rebase because i915 has lost a lot of drmP.h includes, but
not all: Through drm_crtc_helper.h > drm_modeset_helper.h -> drmP.h
there was still one, which this patch largely removes. Which means
rolling out lots more includes all over.
This will also conflict with ongoing drmP.h cleanup by others I
expect.
v3: Rebase on top of atomic bochs.
v4: Review from Laurent for bridge/rcar/omap/shmob/core bits:
- (re)move some of the added includes, use the better include files in
other places (all suggested from Laurent adopted unchanged).
- sort alphabetically
v5: Actually try to sort them, and while at it, sort all the ones I
touch.
v6: Rebase onto i915 changes.
v7: Rebase once more.
Acked-by: Harry Wentland <harry.wentland@amd.com>
Acked-by: Sam Ravnborg <sam@ravnborg.org>
Cc: Sam Ravnborg <sam@ravnborg.org>
Cc: Jani Nikula <jani.nikula@linux.intel.com>
Cc: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Acked-by: Rodrigo Vivi <rodrigo.vivi@intel.com>
Acked-by: Benjamin Gaignard <benjamin.gaignard@linaro.org>
Acked-by: Jani Nikula <jani.nikula@intel.com>
Acked-by: Neil Armstrong <narmstrong@baylibre.com>
Acked-by: Oleksandr Andrushchenko <oleksandr_andrushchenko@epam.com>
Acked-by: CK Hu <ck.hu@mediatek.com>
Acked-by: Alex Deucher <alexander.deucher@amd.com>
Acked-by: Sam Ravnborg <sam@ravnborg.org>
Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Acked-by: Liviu Dudau <liviu.dudau@arm.com>
Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
Cc: linux-arm-kernel@lists.infradead.org
Cc: virtualization@lists.linux-foundation.org
Cc: etnaviv@lists.freedesktop.org
Cc: linux-samsung-soc@vger.kernel.org
Cc: intel-gfx@lists.freedesktop.org
Cc: linux-mediatek@lists.infradead.org
Cc: linux-amlogic@lists.infradead.org
Cc: linux-arm-msm@vger.kernel.org
Cc: freedreno@lists.freedesktop.org
Cc: nouveau@lists.freedesktop.org
Cc: spice-devel@lists.freedesktop.org
Cc: amd-gfx@lists.freedesktop.org
Cc: linux-renesas-soc@vger.kernel.org
Cc: linux-rockchip@lists.infradead.org
Cc: linux-stm32@st-md-mailman.stormreply.com
Cc: linux-tegra@vger.kernel.org
Cc: xen-devel@lists.xen.org
Link: https://patchwork.freedesktop.org/patch/msgid/20190117210334.13234-1-daniel.vetter@ffwll.ch
Let's solve the mystery of commit bf1178c989 ("drm/bridge:
ti-sn65dsi86: Add mystery delay to enable()"). Specifically the
reason we needed that mystery delay is that we weren't paying
attention to HPD.
Looking at the datasheet for the same panel that was tested for the
original commit, I see there's a timing "t3" that times from power on
to the aux channel being operational. This time is specced as 0 - 200
ms. The datasheet says that the aux channel is operational at exactly
the same time that HPD is asserted.
Scoping the signals on this board showed that HPD was asserted 84 ms
after power was asserted. That very closely matches the magic 70 ms
delay that we had. ...and actually, in my testing the 70 ms wasn't
quite enough of a delay and some percentage of the time the display
didn't come up until I bumped it to 100 ms (presumably 84 ms would
have worked too).
To solve this, we tried to hook up the HPD signal in the bridge.
...but in doing so we found that that the bridge didn't report that
HPD was asserted until ~280 ms after we powered it (!). This is
explained by looking at the sn65dsi86 datasheet section "8.4.5.1 HPD
(Hot Plug/Unplug Detection)". Reading there we see that the bridge
isn't even intended to report HPD until 100 ms after it's asserted.
...but that would have left us at 184 ms. The extra 100 ms
(presumably) comes from this part in the datasheet:
> The HPD state machine operates off an internal ring oscillator. The
> ring oscillator frequency will vary [ ... ]. The min/max range in
> the HPD State Diagram refers to the possible times based off
> variation in the ring oscillator frequency.
Given that the 280 ms we'll end up delaying if we hook up HPD is
_slower_ than the 200 ms we could just hardcode, for now we'll solve
the problem by just hardcoding a 200 ms delay in the panel driver
using the patch in this series ("drm/panel: simple: Support panels
with HPD where HPD isn't connected").
If we later find a panel that needs to use this bridge where we need
HPD then we'll have to come up with some new code to handle it. Given
the silly debouncing in the bridge chip, though, it seems unlikely.
One last note is that I tried to solve this through another way: In
ti_sn_bridge_enable() I tried to use various combinations of
dp_dpcd_writeb() and dp_dpcd_readb() to detect when the aux channel
was up. In theory that would let me detect _exactly_ when I could
continue and do link training. Unfortunately even if I did an aux
transfer w/out waiting I couldn't see any errors. Possibly I could
keep looping over link training until it came back with success, but
that seemed a little overly hacky to me.
Reviewed-by: Sean Paul <sean@poorly.run>
Reviewed-by: Andrzej Hajda <a.hajda@samsung.com>
Signed-off-by: Douglas Anderson <dianders@chromium.org>
Signed-off-by: Sean Paul <seanpaul@chromium.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20181025222134.174583-4-dianders@chromium.org
This patch adds a 70ms mystery delay to the bridge driver in enable.
By experimentation, it seems like it can go anywhere up until we
initiate semi-auto link training. If we don't have the delay, link
training fails.
I tried to root cause this as best I could, but neither the datasheet
for the panel nor the bridge mention a delay of this magnitude in their
timing requirements. So for now, add the mystery delay until someone
figures out a better fix.
Changes in v3:
- Added to the set
Cc: Sandeep Panda <spanda@codeaurora.org>
Reviewed-by: Sandeep Panda <spanda@codeaurora.org>
Signed-off-by: Sean Paul <seanpaul@chromium.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20180813213058.184821-8-sean@poorly.run
Instead of just waiting 20ms for training to complete, actually poll the
status to ensure training is finished.
Changes in v3:
- Added to the set
Cc: Sandeep Panda <spanda@codeaurora.org>
Reviewed-by: Sandeep Panda <spanda@codeaurora.org>
Signed-off-by: Sean Paul <seanpaul@chromium.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20180813213058.184821-7-sean@poorly.run
Instead of just waiting and hoping, actually poll for the pll lock to be
acquired. As a bonus, this should be significantly faster than the
sleep.
Changes in v3:
- Added to the set
Cc: Sandeep Panda <spanda@codeaurora.org>
Reviewed-by: Sandeep Panda <spanda@codeaurora.org>
Signed-off-by: Sean Paul <seanpaul@chromium.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20180813213058.184821-6-sean@poorly.run
prepare() is the old-timey way to say pre_enable(). It should be called
before modeset. This fixes an issue where the panel on cheza must have
the regulator always-on/boot-on for it to work.
Changes in v3:
- Added to the set
Cc: Sandeep Panda <spanda@codeaurora.org>
Reviewed-by: Sandeep Panda <spanda@codeaurora.org>
Signed-off-by: Sean Paul <seanpaul@chromium.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20180813213058.184821-5-sean@poorly.run
This was hand-rolled in the first version, and will surely be useful as
we expand the driver to support more varied use cases.
Changes in v2:
- Change subject prefix s/panel/bridge/
- Downgrade warning in poll function to error message
- Fix DP_EDP_CONFIGURATION_SET write value (Sandeep)
- Mask upper 8 bits of msg->address (Sandeep)
- Check aux cmd status for errors after completing the send (Sandeep)
- Remove length check since it's covered in the aux status
- Flip the READ check in transfer to WRITE check + early exit
Changes in v3:
- Added to the set
- Wrapped (x) in WDATA/RDATA #defines
- Replace readx_poll* with regmap_read_poll*
Cc: Sandeep Panda <spanda@codeaurora.org>
Reviewed-by: Sandeep Panda <spanda@codeaurora.org>
Signed-off-by: Sean Paul <seanpaul@chromium.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20180813213058.184821-4-sean@poorly.run
Order registers by offset and rename bits & masks to match the
datasheet. This makes the driver a bit easier to grok and
cross-reference with the datasheet.
Changes in v3:
- Added to the set
Cc: Sandeep Panda <spanda@codeaurora.org>
Reviewed-by: Sandeep Panda <spanda@codeaurora.org>
Signed-off-by: Sean Paul <seanpaul@chromium.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20180813213058.184821-3-sean@poorly.run
This function name was changed to drm_connector_attach_encoder().
Unfortunately this driver was posted on the list before that change, and
applied after
Fixes: a095f15c00 ("drm/bridge: add support for sn65dsi86 bridge
driver")
Cc: Sandeep Panda <spanda@codeaurora.org>
Cc: Andrzej Hajda <a.hajda@samsung.com>
Cc: Archit Taneja <architt@codeaurora.org>
Cc: Laurent Pinchart <Laurent.pinchart@ideasonboard.com>
Reviewed-by: Sandeep Panda <spanda@codeaurora.org>
Signed-off-by: Sean Paul <seanpaul@chromium.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20180730174225.257255-1-seanpaul@chromium.org
Add support for TI's sn65dsi86 dsi2edp bridge chip.
The chip converts DSI transmitted signal to eDP signal,
which is fed to the connected eDP panel.
This chip can be controlled via either i2c interface or
dsi interface. Currently in driver all the control registers
are being accessed through i2c interface only.
Also as of now HPD support has not been added to bridge
chip driver.
Changes in v1:
- Split the dt-bindings and the driver support into separate patches
(Andrzej Hajda).
- Use of gpiod APIs to parse and configure gpios instead of obsolete ones
(Andrzej Hajda).
- Use macros to define the register offsets (Andrzej Hajda).
Changes in v2:
- Separate out edp panel specific HW resource handling from bridge
driver and create a separate edp panel drivers to handle panel
specific mode information and HW resources (Sean Paul).
- Replace pr_* APIs to DRM_* APIs to log error or debug information
(Sean Paul).
- Remove some of the unnecessary structure/variable from driver (Sean
Paul).
- Rename the function and structure prefix "sn65dsi86" to "ti_sn_bridge"
(Sean Paul / Rob Herring).
- Remove most of the hard-coding and modified the bridge init sequence
based on current mode (Sean Paul).
- Remove the existing function to retrieve the EDID data and
implemented this as an i2c_adapter and use drm_get_edid() (Sean Paul).
- Remove the dummy irq handler implementation, will add back the
proper irq handling later (Sean Paul).
- Capture the required enable gpios in a single array based on dt entry
instead of having individual descriptor for each gpio (Sean Paul).
Changes in v3:
- Remove usage of irq_gpio and replace it as "interrupts" property (Rob
Herring).
- Remove the unnecessary header file inclusions (Sean Paul).
- Rearrange the header files in alphabetical order (Sean Paul).
- Use regmap interface to perform i2c transactions.
- Update Copyright/License field and address other review comments
(Jordan Crouse).
Changes in v4:
- Update License/Copyright (Sean Paul).
- Add Kconfig and Makefile changes (Sean Paul).
- Drop i2c gpio handling from this bridge driver, since i2c sda/scl gpios
will be handled by i2c master.
- Update required supplies names.
- Remove unnecessary goto statements (Sean Paul).
- Add mutex lock to power_ctrl API to avoid race conditions (Sean
Paul).
- Add support to parse reference clk frequency from dt(optional).
- Update the bridge chip enable/disable sequence.
Changes in v5:
- Fixed Kbuild test service reported warnings.
Changes in v6:
- Use PM runtime based ref-counting instead of local ref_count mechanism
(Stephen Boyd).
- Clean up some debug logs and indentations (Sean Paul).
- Simplify dp rate calculation (Sean Paul).
- Add support to configure refclk based on input REFCLK pin or DACP/N
pin (Stephen Boyd).
Changes in v7:
- Use static supply entries instead of dynamic allocation (Andrzej
Hajda).
- Defer bridge driver probe if panel is not probed (Andrzej Hajda).
- Update of_graph APIs for correct node reference management. (Andrzej
Hajda).
- Remove local display_mode object (Andrzej Hajda).
- Remove version id check function from driver.
Changes in v8:
- Move dsi register/attach function to bridge driver probe (Andrzej
Hajda).
- Introduce a new helper function to write 16bit words into consecutive
registers (Andrzej Hajda).
- Remove unnecessary macros (Andrzej Hajda).
Changes in v9:
- Remove dsi register/attach from bridge probe, since dsi dev register
completion also waits for any panel or bridge to get added. This creates
deadlock situation when bridge driver calls dsi dev register and
attach before bridge add, in its probe function.
- Fix issues faced during testing of bridge driver on actual HW.
- Remove unnecessary initializations (Stephen Boyd).
- Use local refclk lut size instead of global macro (Sean Paul).
Changes in v10:
- Use refclk to determine if continuous dsi clock is needed or not.
Changes in v11:
- Read DPPLL_SRC register to determine continuous clock instead of
using refclk handle (Stephen Boyd).
Changes in v12:
- Explain in comment as in why dsi dev registration is done in
bridge_attach (Andrzej Hajda).
- Move HPD disable to bridge_pre_enable (Andrzej Hajda).
- Make panel/DDC exclusive until HPD support is added (Andrzej Hajda).
Changes in v13:
- eDP panels report EDID via DP-AUX channel, so remove support for
dedicated DDC line (Andrzej Hajda).
Changes in v14:
- Remove unnecessary drm_panel checks (Andrzej Hajda).
Signed-off-by: Sandeep Panda <spanda@codeaurora.org>
Reviewed-by: Andrzej Hajda <a.hajda@samsung.com>
Signed-off-by: Andrzej Hajda <a.hajda@samsung.com>
Link: https://patchwork.freedesktop.org/patch/msgid/1532069642-21392-1-git-send-email-spanda@codeaurora.org
Harigovindan P