[PATCH v9 04/18] drm: exynos: dsi: Fix MIPI_DSI*_NO_* mode flags

[Marek Szyprowski]

On 12.12.2022 10:03, Jagan Teki wrote:
>   On Mon, Dec 12, 2022 at 2:28 PM Marek Szyprowski
> <m.szyprowski at samsung.com> wrote:
>> Hi Jagan,
>>
>> On 09.12.2022 16:23, Jagan Teki wrote:
>>> HFP/HBP/HSA/EOT_PACKET modes in Exynos DSI host specifies
>>> 0 = Enable and 1 = Disable.
>>>
>>> The logic for checking these mode flags was correct before
>>> the MIPI_DSI*_NO_* mode flag conversion.
>>>
>>> Fix the MIPI_DSI*_NO_* mode flags handling.
>>>
>>> Fixes: <0f3b68b66a6d> ("drm/dsi: Add _NO_ to MIPI_DSI_* flags disabling
>>> features")
>>> Reviewed-by: Nicolas Boichat <drinkcat at chromium.org>
>>> Reported-by: Sébastien Szymanski <sebastien.szymanski at armadeus.com>
>>> Signed-off-by: Jagan Teki <jagan at amarulasolutions.com>
>>> ---
>>> Changes for v9:
>>> - none
>>>
>>>    drivers/gpu/drm/exynos/exynos_drm_dsi.c | 8 ++++----
>>>    1 file changed, 4 insertions(+), 4 deletions(-)
>>>
>>> diff --git a/drivers/gpu/drm/exynos/exynos_drm_dsi.c b/drivers/gpu/drm/exynos/exynos_drm_dsi.c
>>> index e5b1540c4ae4..50a2a9ca88a9 100644
>>> --- a/drivers/gpu/drm/exynos/exynos_drm_dsi.c
>>> +++ b/drivers/gpu/drm/exynos/exynos_drm_dsi.c
>>> @@ -805,15 +805,15 @@ static int exynos_dsi_init_link(struct exynos_dsi *dsi)
>>>                        reg |= DSIM_AUTO_MODE;
>>>                if (dsi->mode_flags & MIPI_DSI_MODE_VIDEO_HSE)
>>>                        reg |= DSIM_HSE_MODE;
>>> -             if (!(dsi->mode_flags & MIPI_DSI_MODE_VIDEO_NO_HFP))
>>> +             if (dsi->mode_flags & MIPI_DSI_MODE_VIDEO_NO_HFP)
>>>                        reg |= DSIM_HFP_MODE;
>>> -             if (!(dsi->mode_flags & MIPI_DSI_MODE_VIDEO_NO_HBP))
>>> +             if (dsi->mode_flags & MIPI_DSI_MODE_VIDEO_NO_HBP)
>>>                        reg |= DSIM_HBP_MODE;
>>> -             if (!(dsi->mode_flags & MIPI_DSI_MODE_VIDEO_NO_HSA))
>>> +             if (dsi->mode_flags & MIPI_DSI_MODE_VIDEO_NO_HSA)
>>>                        reg |= DSIM_HSA_MODE;
>>>        }
>>>
>>> -     if (!(dsi->mode_flags & MIPI_DSI_MODE_NO_EOT_PACKET))
>>> +     if (dsi->mode_flags & MIPI_DSI_MODE_NO_EOT_PACKET)
>>>                reg |= DSIM_EOT_DISABLE;
>>>
>>>        switch (dsi->format) {
>>
>> Huh, this changes the logic in the driver! I've spent another half of
>> the night trying to figure out why v8 and v9 doesn't work on all my
>> Exynos boards with DSI panels again...
>>
>> Please drop this patch from this series. If you want to get the Exynos
>> DSI -> Samsung DSIM conversion merged, please focus on the core patches
>> and don't add more random 'fixes' to each new version.
>>
>> This change has to be discussed separately. The values written by the
>> Exynos DSI driver to the registers ARE CORRECT and DSI panels work fine
>> with such configuration. So either everything is correct, or these flags
>> are reversed both in the Exynos DSI driver AND at least tested DSI
>> panels (s6e8aa0, s6e3ha2, s6e63j0x03). I would need to check this in
>> panel datasheets if I manage to get them.
> This issue was reproduced as part of the series in v7 in i.MX8m
> platform and reported by Sébastien Szymanski [1] and TRM matches the
> fix as well.
>
> [1] https://lore.kernel.org/all/4c9475d0-f76f-0c59-1208-6e5395496c9e@armadeus.com/

Then please append the following changes to this patch to keep current 
code working:

diff --git a/drivers/gpu/drm/panel/panel-samsung-s6e3ha2.c 
b/drivers/gpu/drm/panel/panel-samsung-s6e3ha2.c
index 1355b2c27932..2a33602372d9 100644
--- a/drivers/gpu/drm/panel/panel-samsung-s6e3ha2.c
+++ b/drivers/gpu/drm/panel/panel-samsung-s6e3ha2.c
@@ -692,7 +692,9 @@ static int s6e3ha2_probe(struct mipi_dsi_device *dsi)

         dsi->lanes = 4;
         dsi->format = MIPI_DSI_FMT_RGB888;
-       dsi->mode_flags = MIPI_DSI_CLOCK_NON_CONTINUOUS;
+       dsi->mode_flags = MIPI_DSI_CLOCK_NON_CONTINUOUS
+               | MIPI_DSI_MODE_VIDEO_NO_HFP | MIPI_DSI_MODE_VIDEO_NO_HBP
+               | MIPI_DSI_MODE_VIDEO_NO_HSA | MIPI_DSI_MODE_NO_EOT_PACKET;

         ctx->supplies[0].supply = "vdd3";
         ctx->supplies[1].supply = "vci";
diff --git a/drivers/gpu/drm/panel/panel-samsung-s6e63j0x03.c 
b/drivers/gpu/drm/panel/panel-samsung-s6e63j0x03.c
index 3223a9d06a50..bb47dbfdd7ee 100644
--- a/drivers/gpu/drm/panel/panel-samsung-s6e63j0x03.c
+++ b/drivers/gpu/drm/panel/panel-samsung-s6e63j0x03.c
@@ -446,7 +446,8 @@ static int s6e63j0x03_probe(struct mipi_dsi_device *dsi)

         dsi->lanes = 1;
         dsi->format = MIPI_DSI_FMT_RGB888;
-       dsi->mode_flags = MIPI_DSI_MODE_NO_EOT_PACKET;
+       dsi->mode_flags = MIPI_DSI_MODE_VIDEO_NO_HFP
+               | MIPI_DSI_MODE_VIDEO_NO_HBP | MIPI_DSI_MODE_VIDEO_NO_HSA;

         ctx->supplies[0].supply = "vdd3";
         ctx->supplies[1].supply = "vci";
diff --git a/drivers/gpu/drm/panel/panel-samsung-s6e8aa0.c 
b/drivers/gpu/drm/panel/panel-samsung-s6e8aa0.c
index 362eb10f10ce..c51d07ec1529 100644
--- a/drivers/gpu/drm/panel/panel-samsung-s6e8aa0.c
+++ b/drivers/gpu/drm/panel/panel-samsung-s6e8aa0.c
@@ -990,8 +990,6 @@ static int s6e8aa0_probe(struct mipi_dsi_device *dsi)
         dsi->lanes = 4;
         dsi->format = MIPI_DSI_FMT_RGB888;
         dsi->mode_flags = MIPI_DSI_MODE_VIDEO | MIPI_DSI_MODE_VIDEO_BURST
-               | MIPI_DSI_MODE_VIDEO_NO_HFP | MIPI_DSI_MODE_VIDEO_NO_HBP
-               | MIPI_DSI_MODE_VIDEO_NO_HSA | MIPI_DSI_MODE_NO_EOT_PACKET
                 | MIPI_DSI_MODE_VSYNC_FLUSH | 
MIPI_DSI_MODE_VIDEO_AUTO_VERT;

         ret = s6e8aa0_parse_dt(ctx);


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