Re: [PATCH v7 drm-dp 5/9] drm/hisilicon/hibmc: Getting connector info and EDID by using AUX channel

From: Yongbang Shi
Date: Sat Mar 29 2025 - 02:13:19 EST


On Fri, Mar 28, 2025 at 12:28:14PM +0200, Jani Nikula wrote:
On Fri, 28 Mar 2025, Yongbang Shi <shiyongbang@xxxxxxxxxx> wrote:
On Thu, 27 Mar 2025, Yongbang Shi <shiyongbang@xxxxxxxxxx> wrote:
在 2025/3/26 17:32, Jani Nikula 写道:
On Tue, 25 Mar 2025, Yongbang Shi <shiyongbang@xxxxxxxxxx> wrote:
On Mon, 24 Mar 2025, Yongbang Shi <shiyongbang@xxxxxxxxxx> wrote:
On Wed, 19 Mar 2025, Yongbang Shi <shiyongbang@xxxxxxxxxx> wrote:
From: Baihan Li <libaihan@xxxxxxxxxx>

Add registering drm_aux and use it to get connector edid with drm
functions. Add ddc channel in connector initialization to put drm_aux
in drm_connector.

Signed-off-by: Baihan Li <libaihan@xxxxxxxxxx>
Signed-off-by: Yongbang Shi <shiyongbang@xxxxxxxxxx>
Reviewed-by: Dmitry Baryshkov <dmitry.baryshkov@xxxxxxxxxx>
---
ChangeLog:
v6 -> v7:
- add if statement about drm aux in hibmc_dp_connector_get_modes(), suggested by Jani Nikula
I don't understand this, and I did not suggest such a thing.

BR,
Jani.

Hi Jani,

Is the modification of v8 correct?
I never received that for whatever reason.
Here's the link: https://lore.kernel.org/all/20250320101455.2538835-1-shiyongbang@xxxxxxxxxx/
Thanks.

The EDID handling looks fine.

AFAICT you leak dp->aux.name though.


BR,
Jani.
Thanks for for reminding me, actually the dp->aux.name was written because I misunderstood what you meant in V7,
and I deleted it in V8.
This is in the link you posted:

+ dp->aux.name = kasprintf(GFP_KERNEL, "HIBMC DRM dp aux");

Hi Jani,

I got it. I think I can change it to devm_kasprintf() in next bug fix patch, is that ok?
Maybe. I don't have the time to look into hibmc details.
I don't either, but it looks suspicious to me. devm_kasprintf will be
freed when the device will be removed, but the DP Aux bus is probably
staying for a bit longer?

Maxime

Hi Ripard,

I will bind it to my hibmc device, and aux_unregister is in early_unregister callback of dp's connector_funcs,
which is before the hibmc_pci_remove(), so I think it work good.