Re: [PATCH v2] drm: bridge: tc358764: Use drm panel_bridge API

[Marek Szyprowski <m.szyprowski@samsung.com>]

Hi Jagan,

On 15.12.2021 13:59, Jagan Teki wrote:
> On Wed, Dec 15, 2021 at 5:30 PM Marek Szyprowski
> <m.szyprowski@samsung.com> wrote:
>> On 15.12.2021 11:04, Jagan Teki wrote:
>>> Replace the manual panel handling code by a drm panel_bridge via
>>> devm_drm_of_get_bridge().
>>>
>>> Adding panel_bridge handling,
>>>
>>> - Drops drm_connector and related operations as drm_bridge_attach
>>>     creates connector during attachment.
>>>
>>> - Drops panel pointer and panel healpers.
>>>
>>> This simplifies the driver and allows all components in the display
>>> pipeline to be treated as bridges.
>>>
>>> Signed-off-by: Jagan Teki <jagan@amarulasolutions.com>
>> I just tested it on top of linux-next with "drm: of: Lookup if child
>> node has panel or bridge" patch. Sadly it still doesn't work on
>> Exynos5250-based Arndale board:
>>
>> OF: graph: no port node found in /soc/hdmi@14530000
>> [drm] Exynos DRM: using 14400000.fimd device for DMA mapping operations
>> exynos-drm exynos-drm: bound 14400000.fimd (ops fimd_component_ops)
>> exynos-drm exynos-drm: bound 14450000.mixer (ops mixer_component_ops)
>> OF: graph: no port node found in /soc/dsi@14500000
>> exynos-drm exynos-drm: bound 14500000.dsi (ops exynos_dsi_component_ops)
>> exynos-drm exynos-drm: bound 14530000.hdmi (ops hdmi_component_ops)
>> exynos-drm exynos-drm: [drm] Cannot find any crtc or sizes
>> exynos-drm exynos-drm: [drm] Cannot find any crtc or sizes
>> [drm] Initialized exynos 1.1.0 20180330 for exynos-drm on minor 0
>> panfrost 11800000.gpu: clock rate = 533000000
>> panfrost 11800000.gpu: mali-t600 id 0x600 major 0x0 minor 0x0 status 0x1
>> panfrost 11800000.gpu: features: 00000000,10206000, issues:
>> 00000000,31b4dfff
>> panfrost 11800000.gpu: Features: L2:0x07110206 Shader:0x00000000
>> Tiler:0x00000809 Mem:0x1 MMU:0x00002830 AS:0xf JS:0x7
>> panfrost 11800000.gpu: shader_present=0xf l2_present=0x1
>> [drm] Initialized panfrost 1.2.0 20180908 for 11800000.gpu on minor 1
>> ------------[ cut here ]------------
>> WARNING: CPU: 1 PID: 7 at drivers/gpu/drm/drm_atomic_state_helper.c:494
>> drm_atomic_helper_connector_duplicate_state+0x60/0x68
> Known problem, it require 1/6 from Bridge conversation series. We can
> move this patch into conversion series next time or while merging.

Indeed, with the 1/6 patch it works fine on Exynos5250 based Arndale board.

Tested-by: Marek Szyprowski <m.szyprowski@samsung.com>

Best regards

-- 
Marek Szyprowski, PhD
Samsung R&D Institute Poland