Hi All,

On 26/05/25 18:43, Tommaso Merciai wrote:
Hi All,

On 26/05/25 16:28, Laurent Pinchart wrote:
On Mon, May 26, 2025 at 04:13:23PM +0200, Tommaso Merciai wrote:
On 26/05/25 16:02, Tommaso Merciai wrote:
On 26/05/25 15:18, Dmitry Baryshkov wrote:
On 26/05/2025 14:40, Maxime Ripard wrote:
On Mon, May 26, 2025 at 01:19:23PM +0200, Tommaso Merciai wrote:
On 26/05/25 12:49, Laurent Pinchart wrote:
On Mon, May 26, 2025 at 11:58:37AM +0200, Tommaso Merciai wrote:
On 26/05/25 11:26, Maxime Ripard wrote:
On Mon, May 26, 2025 at 10:54:52AM +0200, Tommaso Merciai wrote:
After adv7511_mode_set() was merged into .atomic_enable(), only the
native resolution is working when using modetest.

This is caused by incorrect timings: adv7511_mode_set() must not be
merged into .atomic_enable().

Move adv7511_mode_set() back to the .mode_set() callback in
drm_bridge_funcs to restore correct behavior.

Fixes: 0a9e2f0a6466 ("drm/bridge: adv7511: switch to the HDMI
connector helpers")
Reported-by: Biju Das <biju.das...@bp.renesas.com>
Closes: https://lore.kernel.org/all/aDB8bD6cF7qiSpKd@tom- desktop/ Signed-off-by: Tommaso Merciai <tommaso.merciai...@bp.renesas.com>

Explaining why, both in the commit log and the comments, would be
nice.
Because I can't think of any good reason it just can't work for that
bridge.

Sorry, let me clarify and share with you some details:

adv7511_mode_set:
     - Is setting up timings registers for the DSI2HDMI bridge in
our case
       we are using ADV7535 bridge.

rzg2l_mipi_dsi_atomic_enable:
     - Is setting up the vclock for the DSI ip

Testing new/old implementation a bit we found the following:

root@smarc-rzg3e:~# modetest -M rzg2l-du -d -s HDMI-
A-1:800x600-56.25@XR24
setting mode 800x600-56.25Hz on connectors HDMI-A-1, crtc 62
[   49.273134] adv7511_mode_set_old: drm_mode_vrefresh(mode) = 56
[   49.281006] rzg2l_mipi_dsi_atomic_enable: mode->clock: 36000

root@smarc-rzg3e:~# modetest -M rzg2l-du -d -s HDMI-
A-1:800x600-56.25@XR24
setting mode 800x600-56.25Hz on connectors HDMI-A-1, crtc 62
[   74.076881] rzg2l_mipi_dsi_atomic_enable: mode->clock: 36000
[   74.092130] adv7511_mode_set: drm_mode_vrefresh(adj_mode) = 56

Same result but different timing (in function call perspective):

     - old: adv7511_mode_set() is call before
rzg2l_mipi_dsi_atomic_enable()
     - new: adv7511_mode_set() is call after
rzg2l_mipi_dsi_atomic_enable()

What is "old" and "new" here ? Is it before and after Dmitry's
patch, or
before and after yours ? Please be precise when describing problems.

Sorry, you are completely right:

   - old --> before Dmitry's patch
   - new --> after Dmitry's patch


What do you think? Thanks in advance.

You're only explaining above what the "old" and "new" behaviours are,
and claiming one of them is causing an issue, but you're not
explaining
*why* it causes an issue. That's what your commit message is
expected to
detail.


Thanks for the clarification! :)
I will send v2 explaining better this.

In particular, if the driver needs to have mode_set called before
atomic_enable, you should say why moving the call to mode_set earlier in
the function wouldn't work.

It might be the same thing as we had on PS8640: it had to be brought
up before the host starts the DSI link, so that there is no clock
input on the DSI clock lane.


Some updates on my side:

I'm not seeing any differences from a regs perspective when using the
old driver version (before Dmitry's patch) and the new driver version
(after Dmitry's patch).

In particular, i2cdump -f -y 7 0x4c shows me the same result.

Please ignore this (wrong address)

The right test is: i2cdump -f -y 7 0x3d

And I'm seeing the following differences:

# WORK:
reg | val
0x3d → 0x00
0x3e → 0x00

# DON't WORK
reg | val
0x3d → 0x10
0x3e → 0x40

Unfortunately, since I don't have the ADV7535 datasheet, I believe this
issue may be related to the functions call sequence.

You could try to get the documentation from Analog Devices.

This being said, the above registers are documented in the ADV7511
programming guide, which is publicly available. They may differ in the
ADV7535 though.

I agree with Dmitry's theory.

Let me gently know if you need some more test on my side. Thanks in
advance.


FYI, I've tested the following pipeline:

DU1 (RGB Output) -> adv7513 -> HDMI Panel

All working fine on my side with the Dmitry's patch.
Same driver, But broken on DSI interface(ADV7535)

Updating horizontal/vertical porch params after drm_mode_copy() into the adv7511_mode_set() fixes the issue.

In particular:

adv7511_bridge_atomic_enable() call adv7511_power_on(), then adv7511_dsi_config_timing_gen() that is responsible to update h/v porch params.

But during the adv7511_mode_set() adv7511->curr_mode change and this is not reflected into the h/v porch regs, then h/w porch regs are keeping the old values.

I will send fix in next version.

Thanks & Regards,
Tommaso


Thanks & Regards,
Tommaso



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