Re: [PATCH v2 drm-dp 07/10] drm/hisilicon/hibmc: fix dp and vga cannot show together

From: Yongbang Shi
Date: Mon Jun 30 2025 - 09:18:16 EST



On Fri, Jun 20, 2025 at 05:31:01PM +0800, Yongbang Shi wrote:
From: Baihan Li <libaihan@xxxxxxxxxx>

If VGA and DP connected together, there will be only one can get crtc.
Add encoder possible_clones to support two connectors enable.

Fixes: 0ab6ea261c1f ("drm/hisilicon/hibmc: add dp module in hibmc")
Fixes: 3c7623fb5bb6 ("drm/hisilicon/hibmc: Enable this hot plug detect of irq feature")
Signed-off-by: Baihan Li <libaihan@xxxxxxxxxx>
Signed-off-by: Yongbang Shi <shiyongbang@xxxxxxxxxx>
---
ChangeLog:
v1 -> v2:
- don't tie VGA and DP status, suggested by Dmitry Baryshkov.
- use crtc clone to let 2 connectors can display simultaneous
How does this help? I had an impression that your hw can actually
display only either to DP or to VGA. Can it send the same (aka cloned)
video stream to both connectors at the same time?

Right, we support it. We support using KVM remotely operated, and
local maintenance using DP at the same time. KVM and VGA are both
using VDAC connector in driver. Actually, there are three outputs showing
at the same time.

Thanks,
Baihan.


---
drivers/gpu/drm/hisilicon/hibmc/hibmc_drm_drv.c | 8 ++++++++
1 file changed, 8 insertions(+)