- 01 Aug, 2023 24 commits
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Douglas Anderson authored
These days, it's fairly common to see panels that have touchscreens attached to them. The panel and the touchscreen can somewhat be thought of as totally separate devices and, historically, this is how Linux has treated them. However, treating them as separate isn't necessarily the best way to model the two devices, it was just that there was no better way. Specifically, there is little practical reason to have the touchscreen powered on when the panel is turned off, but if we model the devices separately we have no way to keep the two devices' power states in sync with each other. The issue described above makes it sound as if the problem here is just about efficiency. We're wasting power keeping the touchscreen powered up when the screen is off. While that's true, the problem can go deeper. Specifically, hardware designers see that there's no reason to have the touchscreen on while the screen is off and then build hardware assuming that software would never turn the touchscreen on while the screen is off. In the very simplest case of hardware designs like this, the touchscreen and the panel share some power rails. In most cases, this turns out not to be terrible and is, again, just a little less efficient. Specifically if we tell Linux that the touchscreen and the panel are using the same rails then Linux will keep the rails on when _either_ device is turned on. That ends to work OK-ish, but now if you turn the panel off not only will the touchscreen remain powered, but the power rails for the panel itself won't be switched off, burning extra power. The above two inefficiencies are _extra_ minor when you consider the fact that laptops rarely spend much time with the screen off. The main use case would be when an external screen (and presumably a power supply) is attached. Unfortunately, it gets worse from here. On sc7180-trogdor-homestar, for instance, the display's TCON (timing controller) sometimes crashes if you don't power cycle it whenever you stop and restart the video stream (like during a modeset). The touchscreen keeping the power rails on causes real problems. One proposal in the homestar timeframe was to move the touchscreen to an always-on rail, dedicating the main power rail to the panel. That caused _different_ problems as talked about in commit 557e05fa ("HID: i2c-hid: goodix: Stop tying the reset line to the regulator"). The end result of all of this was to add an extra regulator to the board, increasing cost. Recently, Cong Yang posted a patch [1] where things are even worse. The panel and touch controller on that system seem even more intimately tied together and really can't be thought of separately. To address this issue, let's start allowing devices to register themselves as "panel followers". These devices will get called after a panel has been powered on and before a panel is powered off. This makes the panel the primary device in charge of the power state, which matches how userspace uses it. The panel follower API should be fairly straightforward to use. The current code assumes that panel followers are using device tree and have a "panel" property pointing to the panel to follow. More flexibility and non-DT implementations could be added as needed. Right now, panel followers can follow the prepare/unprepare functions. There could be arguments made that, instead, they should follow enable/disable. I've chosen prepare/unprepare for now since those functions are guaranteed to power up/power down the panel and it seems better to start the process earlier. A bit of explaining about why this is a roll-your-own API instead of using something more standard: 1. In standard APIs in Linux, parent devices are automatically powered on when a child needs power. Applying that here, it would mean that we'd force the panel on any time someone was listening to the touchscreen. That, unfortunately, would have broken homestar's need (if we hadn't changed the hardware, as per above) where the panel absolutely needs to be able to power cycle itself. While one could argue that homestar is broken hardware and we shouldn't have the API do backflips for it, _officially_ the eDP timing guidelines agree with homestar's needs and the panel power sequencing diagrams show power going off. It's nice to be able to support this. 2. We could, conceibably, try to add a new flag to device_link causing the parent to be in charge of power. Then we could at least use normal pm_runtime APIs. This sounds great, except that we run into problems with initial probe. As talked about in the later patch ("HID: i2c-hid: Support being a panel follower") the initial power on of a panel follower might need to do things (like add sub-devices) that aren't allowed in a runtime_resume function. The above complexities explain why this API isn't using common functions. That being said, this patch is very small and self-contained, so if someone was later able to adapt it to using more common APIs while solving the above issues then that could happen in the future. [1] https://lore.kernel.org/r/20230519032316.3464732-1-yangcong5@huaqin.corp-partner.google.comReviewed-by:
Maxime Ripard <mripard@kernel.org> Signed-off-by:
Douglas Anderson <dianders@chromium.org> Link: https://patchwork.freedesktop.org/patch/msgid/20230727101636.v4.3.Icd5f96342d2242051c754364f4bee13ef2b986d4@changeid
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Douglas Anderson authored
In a whole pile of panel drivers, we have code to make the prepare/unprepare/enable/disable callbacks behave as no-ops if they've already been called. It's silly to have this code duplicated everywhere. Add it to the core instead so that we can eventually delete it from all the drivers. Note: to get some idea of the duplicated code, try: git grep 'if.*>prepared' -- drivers/gpu/drm/panel git grep 'if.*>enabled' -- drivers/gpu/drm/panel NOTE: arguably, the right thing to do here is actually to skip this patch and simply remove all the extra checks from the individual drivers. Perhaps the checks were needed at some point in time in the past but maybe they no longer are? Certainly as we continue transitioning over to "panel_bridge" then we expect there to be much less variety in how these calls are made. When we're called as part of the bridge chain, things should be pretty simple. In fact, there was some discussion in the past about these checks [1], including a discussion about whether the checks were needed and whether the calls ought to be refcounted. At the time, I decided not to mess with it because it felt too risky. Looking closer at it now, I'm fairly certain that nothing in the existing codebase is expecting these calls to be refcounted. The only real question is whether someone is already doing something to ensure prepare()/unprepare() match and enabled()/disable() match. I would say that, even if there is something else ensuring that things match, there's enough complexity that adding an extra bool and an extra double-check here is a good idea. Let's add a drm_warn() to let people know that it's considered a minor error to take advantage of drm_panel's double-checking but we'll still make things work fine. We'll also add an entry to the official DRM todo list to remove the now pointless check from the panels after this patch lands and, eventually, fixup anyone who is triggering the new warning. [1] https://lore.kernel.org/r/20210416153909.v4.27.I502f2a92ddd36c3d28d014dd75e170c2d405a0a5@changeidAcked-by:
Neil Armstrong <neil.armstrong@linaro.org> Reviewed-by:
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Douglas Anderson authored
As talked about in the patch ("drm/panel: Add a way for other devices to follow panel state"), touchscreens that are connected to panels are generally expected to be power sequenced together with the panel they're attached to. Today, nothing provides information allowing you to find out that a touchscreen is connected to a panel. Let's add a phandle for this. The proerty is added to the generic touchscreen bindings and then enabled in the bindings for the i2c-hid backed devices. This can and should be added for other touchscreens in the future, but for now let's start small. Reviewed-by:Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org> Reviewed-by:
Benjamin Tissoires <bentiss@kernel.org> Acked-by:
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Nikita Travkin authored
Add timings for InnoLux N140HCA-EAC. This panel is found on some laptops such as Acer Aspire 1. Signed-off-by:
Nikita Travkin <nikita@trvn.ru> Reviewed-by:
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Miquel Raynal authored
A very basic debugging rule when a device is connected for the first time is to access a read-only register which contains known data in order to ensure the communication protocol is properly working. This driver lacked any read helper which is often a critical piece for speeding-up bring-ups. Add a read helper and use it to verify the communication with the panel is working as soon as possible in order to inform the user early if this is not the case. As this panel may work with no MISO line, the check is discarded in this case. Upon error, we do not fail probing but just warn the user, in case the DT description would be lacking the Rx bus width (which is likely on old descriptions) in order to avoid breaking existing devices. Signed-off-by:
Miquel Raynal <miquel.raynal@bootlin.com> Acked-by:
Sam Ravnborg <sam@ravnborg.org> Acked-by:
Sebastian Reichel <sre@kernel.org> Tested-by: Sebastian Reichel <sre@kernel.org> # no MISO line Signed-off-by:
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Miquel Raynal authored
This panel from Emerging Display Technologies Corporation features an ST7789V2 LCD controller panel inside which is almost identical to what the Sitronix panel driver supports. In practice, the module physical size is specific, and experiments show that the display will malfunction if any of the following situation occurs: * Pixel clock is above 3MHz * Pixel clock is not inverted I could not properly identify the reasons behind these failures, scope captures show valid input signals. Signed-off-by:
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Miquel Raynal authored
The Sitronix datasheet explains BIT(1) of the RGBCTRL register as the DOTCLK/PCLK edge used to sample the data lines: “0” The data is input on the positive edge of DOTCLK “1” The data is input on the negative edge of DOTCLK IOW, this bit implies a falling edge and not a high state. Correct the definition to ease the comparison with the datasheet. Signed-off-by: -
Miquel Raynal authored
The Sitronix controller expects 9-bit words, provide this as default at probe time rather than specifying this in each and every access. Signed-off-by:
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Miquel Raynal authored
The ST7789V LCD controller supports regular SPI wiring, as well as no Rx data line at all. The operating system needs to know whether it can read registers from the device or not. Let's detail this specific design possibility by bounding the spi-rx-bus-width property. Signed-off-by:
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Miquel Raynal authored
The ST7789V LCD controller is also embedded in the ET028013DMA panel. Add a compatible string to describe this other panel. Signed-off-by:
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Sebastian Reichel authored
UNI-T UTi260b has a Inanbo T28CP45TN89 v17 panel. I could not find proper documentation for the panel apart from a technical drawing, but according to the vendor U-Boot it is based on a Sitronix st7789v chip. I generated the init sequence by modifying the default one until proper graphics output has been seen on the device. Reviewed-by:
Michael Riesch <michael.riesch@wolfvision.net> Signed-off-by:
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Sebastian Reichel authored
Add polarity information via mode and bus flags, so that they are no longer hardcoded and forward the information to the DRM stack. This is required for adding panels with different settings. Reviewed-by:
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Sebastian Reichel authored
While the default panel uses invert mode, some panels require non-invert mode instead. Reviewed-by:
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Sebastian Reichel authored
Add support for describing the media bus format in the panel configuration and expose that to userspace. Since both supported formats (RGB565 and RGB666) are using 6 bits per color also hardcode that information. Reviewed-by:
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Sebastian Reichel authored
Move the panel size information to the mode struct, so that different panel sizes can be specified depending on the panel type. Reviewed-by:
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Sebastian Reichel authored
Avoid hard-coding the default_mode and supply it from match data. One additional layer of abstraction has been introduced, which will be needed for specifying other panel information (e.g. bus flags) in the next steps. Reviewed-by:
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Sebastian Reichel authored
Improve error handling in the probe routine, so that probe defer errors are captured in /sys/kernel/debug/devices_deferred Reviewed-by:
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Sebastian Reichel authored
st7789v_spi_write initializes a message with just a single transfer, spi_sync_transfer can be used for that. Reviewed-by:
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Sebastian Reichel authored
The reset pin might not be software controllable from the SoC, so make it optional. Reviewed-by:
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Sebastian Reichel authored
ST7789V_COLMOD_RGB_FMT_18BITS and ST7789V_COLMOD_CTRL_FMT_18BITS are unused in favour of MIPI_DCS_PIXEL_FMT_18BIT, remove them. Reviewed-by:
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Sebastian Reichel authored
SPI device drivers should also have a SPI ID table. Reviewed-by:
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Sebastian Reichel authored
Add compatible value for Inanbo t28cp45tn89 and make reset GPIO non mandatory, since it might not be connected to the CPU. Reviewed-by:
Rob Herring <robh@kernel.org> Signed-off-by:
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Sebastian Reichel authored
Shenzhen INANBO Electronic Technology Co., Ltd. manufacturers TFT/OLED LCD panels. Reviewed-by:
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Arthur Grillo authored
The drm_exec tests where crashing[0] because of a null dereference. This is caused by a new access of the `driver` attribute of `struct drm_driver` on drm_gem_private_object_init(). Alloc the drm_device to fix that. [0] [15:05:24] ================== drm_exec (6 subtests) =================== [15:05:24] [PASSED] sanitycheck ^CERROR:root:Build interruption occurred. Cleaning console. [15:05:50] [ERROR] Test: drm_exec: missing expected subtest! [15:05:50] BUG: kernel NULL pointer dereference, address: 00000000000000b0 [15:05:50] #PF: supervisor read access in kernel mode [15:05:50] #PF: error_code(0x0000) - not-present page [15:05:50] PGD 0 P4D 0 [15:05:50] Oops: 0000 [#1] PREEMPT NOPTI [15:05:50] CPU: 0 PID: 23 Comm: kunit_try_catch Tainted: G N 6.4.0-rc7-02032-ge6303f32 #69 [15:05:50] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.16.2-1.fc37 04/01/2014 [15:05:50] RIP: 0010:drm_gem_private_object_init+0x60/0xc0 Fixes: e6303f32 ("drm: manager to keep track of GPUs VA mappings") Signed-off-by:
Arthur Grillo <arthurgrillo@riseup.net> Tested-by:
Danilo Krummrich <dakr@redhat.com> Acked-by:
Maíra Canal <mcanal@igalia.com> Signed-off-by:
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- 31 Jul, 2023 16 commits
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Dmitry Osipenko authored
Add sync object DRM UAPI support to VirtIO-GPU driver. Sync objects support is needed by native context VirtIO-GPU Mesa drivers, it also will be used by Venus and Virgl contexts. Reviewed-by; Emil Velikov <emil.velikov@collabora.com> Signed-off-by:
Dmitry Osipenko <dmitry.osipenko@collabora.com> Tested-by: Pierre-Eric Pelloux-Prayer <pierre-eric.pelloux-prayer@amd.com> # amdgpu nctx Tested-by: Rob Clark <robdclark@gmail.com> # freedreno nctx Reviewed-by:
Rob Clark <robdclark@gmail.com> Acked-by:
Gurchetan Singh <gurchetansingh@chromium.org> Acked-by:
Gerd Hoffmann <kraxel@redhat.com> Link: https://patchwork.freedesktop.org/patch/msgid/20230416115237.798604-4-dmitry.osipenko@collabora.com
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Thomas Zimmermann authored
Deferred-I/O generator macros generate callbacks for struct fb_ops that operate on memory ranges in I/O address space or system address space. Rename the macros to use the _IOMEM_ and _SYSMEM_ infixes of their underlying helpers. Adapt all users. No functional changes. Signed-off-by:
Thomas Zimmermann <tzimmermann@suse.de> Reviewed-by:
Helge Deller <deller@gmx.de> Link: https://patchwork.freedesktop.org/patch/msgid/20230729193157.15446-5-tzimmermann@suse.de
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Thomas Zimmermann authored
Change the infix for fbdev's DMA-memory helpers from _DMA_ to _DMAMEM_. The helpers perform operations within DMA-able memory, but they don't perform DMA operations. Naming should make this clear. Adapt all users. No functional changes. Signed-off-by:
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Thomas Zimmermann authored
Change the infix for fbdev's system-memory helpers from _SYS_ to _SYSMEM_. The helpers perform operations within system memory, but not on the state of the operating system itself. Naming should make this clear. Adapt all users. No functional changes. Suggested-by:
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Thomas Zimmermann authored
Change the infix for fbdev's I/O-memory helpers from _IO_ to _IOMEM_ to distiguish them from other types of I/O, such as file operations. The helpers operate on memory ranges in the I/O address space and the naming should make this clear. Adapt all users. No functional changes. Suggested-by:
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Marek Vasut authored
The connector type and pixel format are missing for this panel, add them to prevent various drivers from failing to determine either of those parameters. Fixes: 7ee933a1 ("drm/panel: simple: Add support for AUO T215HVN01") Signed-off-by:
Marek Vasut <marex@denx.de> Reviewed-by:
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Guillaume La Roque authored
This driver support the Startek KD070FHFID015, which is a 7-inch TFT LCD display using MIPI DSI interface. Signed-off-by:
Guillaume La Roque <glaroque@baylibre.com> Reviewed-by:
Alexandre Mergnat <amergnat@baylibre.com> Signed-off-by:
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Alexandre Mergnat authored
The Startek KD070FHFID015 is a 7-inch TFT LCD display with a resolution of 1024 x 600 pixels. Reviewed-by:
Conor Dooley <conor.dooley@microchip.com> Signed-off-by:
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Matus Gajdos authored
Add support for TDO TL050HDV35-H1311A LCD panel. Signed-off-by:
Matus Gajdos <matuszpd@gmail.com> Reviewed-by:
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Matus Gajdos authored
Add support for TDO TL050HDV35-H1311A LCD panel. Signed-off-by:
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Dmitry Baryshkov authored
Specify bpc value for the powertip_ph800480t013_idf02 panel to stop drm code from complaining about unexpected bpc value (0). Signed-off-by:
Dmitry Baryshkov <dmitry.baryshkov@linaro.org> Reviewed-by:
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Arnd Bergmann authored
The newly added driver only builds when DRM_DISPLAY_DP_HELPER is enabled: x86_64-linux-ld: drivers/gpu/drm/panel/panel-visionox-r66451.o: in function `visionox_r66451_enable': panel-visionox-r66451.c:(.text+0x105): undefined reference to `drm_dsc_pps_payload_pack' Select both CONFIG_DRM_DISPLAY_DP_HELPER and CONFIG_DRM_DISPLAY_HELPER to ensure the helper function is always available. Fixes: a6dfab27 ("drm/panel: Add driver for Visionox r66451 panel") Signed-off-by:
Arnd Bergmann <arnd@arndb.de> Reviewed-by:
Jessica Zhang <quic_jesszhan@quicinc.com> Signed-off-by:
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Maxime Ripard authored
We've had a couple of tests that weren't really obvious, nor did they document what they were supposed to test. Document that to make it hopefully more obvious. Reviewed-by:
Javier Martinez Canillas <javierm@redhat.com> Reviewed-by:
Maíra Canal <mairacanal@riseup.net> Link: https://lore.kernel.org/r/20230728-kms-kunit-actions-rework-v3-11-952565ccccfe@kernel.orgSigned-off-by:
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Maxime Ripard authored
Now that we have a helper that takes care of an atomic state allocation and cleanup, we can migrate to it to simplify our tests. Reviewed-by:
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Maxime Ripard authored
The new helper to init the locking context allows to remove some boilerplate. Reviewed-by:
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Maxime Ripard authored
The *_mock_device functions allocate a DRM device that needs to be released using drm_dev_unregister. Now that we have a kunit release action API, we can switch to it and don't require any kind of garbage collection from the caller. Reviewed-by:
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