Re: [PATCH v4 05/11] drm/bridge: it6505: increase supports of HDCP repeater ksv devices

[Dmitry Baryshkov]

On Fri, Sep 27, 2024 at 02:18:54AM GMT, Hermes.Wu@xxxxxxxxxx wrote:
> >
> >-----Original Message-----
> >From: Dmitry Baryshkov <dmitry.baryshkov@xxxxxxxxxx> 
> >Sent: Thursday, September 26, 2024 4:07 PM
> >To: Hermes Wu (吳佳宏) <Hermes.Wu@xxxxxxxxxx>
> >Cc: Kenneth Hung (洪家倫) <Kenneth.Hung@xxxxxxxxxx>; Andrzej Hajda <andrzej.hajda@xxxxxxxxx>; Neil Armstrong <neil.armstrong@xxxxxxxxxx>; Robert Foss <rfoss@xxxxxxxxxx>; Laurent Pinchart <Laurent.pinchart@xxxxxxxxxxxxxxxx>; Jonas Karlman <jonas@xxxxxxxxx>; Jernej Skrabec <jernej.skrabec@xxxxxxxxx>; Maarten Lankhorst <maarten.lankhorst@xxxxxxxxxxxxxxx>; Maxime Ripard <mripard@xxxxxxxxxx>; Thomas Zimmermann <tzimmermann@xxxxxxx>; David Airlie <airlied@xxxxxxxxx>; Simona Vetter <simona@xxxxxxxx>; Allen Chen <allen.chen@xxxxxxxxxx>; AngeloGioacchino Del Regno <angelogioacchino.delregno@xxxxxxxxxxxxx>; open list:DRM DRIVERS <dri-devel@xxxxxxxxxxxxxxxxxxxxx>; open list <linux-kernel@xxxxxxxxxxxxxxx>
> >Subject: Re: [PATCH v4 05/11] drm/bridge: it6505: increase supports of HDCP repeater ksv devices
> >
> >On Thu, Sep 26, 2024 at 03:50:14PM GMT, Hermes Wu wrote:
> >> From: Hermes Wu <Hermes.wu@xxxxxxxxxx>
> >> 
> >> A HDCP source shall support max downstream device to 127.
> >> 
> >> Change definition of MAX_HDCP_DOWN_STREAM_COUNT to 127
> >
> >This results in struct it6505 growth by ~0.5 KiB. Please mention it in the commit message.
> >
> >Is it really required to have sha1_input in the constantly allocated structure? I think it's a temporary data, which isn't necessary after processing.
> 
> Change sha1_input with dynamic memory into one commit or 
> 
> change to use temporary data in one and change definition of MAX_HDCP_DOWN_STREAM_COUN in another?

If it's needed during the lifetime, it's fine. Just explain the
necessity to grow the structure in the commit message.

> 
> >> 
> >> Fixes: b5c84a9edcd4 ("drm/bridge: add it6505 driver")
> >> Signed-off-by: Hermes Wu <Hermes.wu@xxxxxxxxxx>
> >> ---
> >>  drivers/gpu/drm/bridge/ite-it6505.c | 2 +-
> >>  1 file changed, 1 insertion(+), 1 deletion(-)
> >> 
> >> diff --git a/drivers/gpu/drm/bridge/ite-it6505.c 
> >> b/drivers/gpu/drm/bridge/ite-it6505.c
> >> index d1f5220e04a6..5d5ce12cd054 100644
> >> --- a/drivers/gpu/drm/bridge/ite-it6505.c
> >> +++ b/drivers/gpu/drm/bridge/ite-it6505.c
> >> @@ -296,7 +296,7 @@
> >>  #define MAX_LANE_COUNT 4
> >>  #define MAX_LINK_RATE HBR
> >>  #define AUTO_TRAIN_RETRY 3
> >> -#define MAX_HDCP_DOWN_STREAM_COUNT 10
> >> +#define MAX_HDCP_DOWN_STREAM_COUNT 127
> >>  #define MAX_CR_LEVEL 0x03
> >>  #define MAX_EQ_LEVEL 0x03
> >>  #define AUX_WAIT_TIMEOUT_MS 15
> >> --
> >> 2.34.1
> >> 
> >
> >-- 
> >With best wishes
> >Dmitry
> >
> 
> BR,
> Hermes
> 

-- 
With best wishes
Dmitry