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Message-ID: <CAA8EJprGjuGFjZnXUxiMZMV=FO9O9CYt06H_nSL82fEOvPytyA@mail.gmail.com>
Date: Fri, 13 Dec 2024 15:16:44 +0200
From: Dmitry Baryshkov <dmitry.baryshkov@...aro.org>
To: Xin Ji <xji@...logixsemi.com>
Cc: Andrzej Hajda <andrzej.hajda@...el.com>, Neil Armstrong <neil.armstrong@...aro.org>,
Robert Foss <rfoss@...nel.org>, Laurent Pinchart <Laurent.pinchart@...asonboard.com>,
Jonas Karlman <jonas@...boo.se>, Jernej Skrabec <jernej.skrabec@...il.com>,
Maarten Lankhorst <maarten.lankhorst@...ux.intel.com>, Maxime Ripard <mripard@...nel.org>,
Thomas Zimmermann <tzimmermann@...e.de>, David Airlie <airlied@...il.com>, Simona Vetter <simona@...ll.ch>,
Bernie Liang <bliang@...logixsemi.com>, Qilin Wen <qwen@...logixsemi.com>,
"treapking@...gle.com" <treapking@...gle.com>,
"dri-devel@...ts.freedesktop.org" <dri-devel@...ts.freedesktop.org>,
"linux-kernel@...r.kernel.org" <linux-kernel@...r.kernel.org>
Subject: Re: [PATCH v3] drm/bridge:anx7625: Update HDCP status at atomic_enable()
On Fri, 13 Dec 2024 at 13:00, Xin Ji <xji@...logixsemi.com> wrote:
>
> Hi Dmitry, sorry, I didn't clear describe the reason.
Please. Do not top-post. Please paste your answer under the question,
not somewhere at the top of the email. This allows us to have a more
constructive dialog. Additional bonus if you can fix your email client
to insert sensible quoting information instead of dumping the headers
of the original email.
>
> Anx7625 implement DSI to DP convert behind USB Type-C port, when user plug into USB Type-C
> Dongle with DP monitor, the user space will enable HDCP feature, then kernel do HDCP and
> output display and set HDCP content to ENABLE, but the issue happened if user manually
> change the monitor's resolution later.
>
> Each time user change the resolution, kernel will call bridge interface .atomic_disable() and
> .atomic_enable(), the old driver will keep HDCP state to ENABLE, this is a BUG, when user
> change the resolution, kernel must change HDCP content too (mustn't keep to ENABLE),
Why? Could you please point me to the corresponding documentation or a
code path in the other driver? Preferably i915, AMD or Nouveau.
> as DRM doc said, kernel cannot change from ENABLE to UNDESIRE, so next patch,
> I'll change it to DESIRE in .atomic_disable().
>
> Thanks!
> Xin
>
> > -----Original Message-----
> > From: Dmitry Baryshkov <dmitry.baryshkov@...aro.org>
> > Sent: Friday, December 13, 2024 6:47 PM
> > To: Xin Ji <xji@...logixsemi.com>
> > Cc: Andrzej Hajda <andrzej.hajda@...el.com>; Neil Armstrong
> > <neil.armstrong@...aro.org>; Robert Foss <rfoss@...nel.org>; Laurent Pinchart
> > <Laurent.pinchart@...asonboard.com>; Jonas Karlman <jonas@...boo.se>;
> > Jernej Skrabec <jernej.skrabec@...il.com>; Maarten Lankhorst
> > <maarten.lankhorst@...ux.intel.com>; Maxime Ripard <mripard@...nel.org>;
> > Thomas Zimmermann <tzimmermann@...e.de>; David Airlie
> > <airlied@...il.com>; Simona Vetter <simona@...ll.ch>; Bernie Liang
> > <bliang@...logixsemi.com>; Qilin Wen <qwen@...logixsemi.com>;
> > treapking@...gle.com; dri-devel@...ts.freedesktop.org; linux-
> > kernel@...r.kernel.org
> > Subject: Re: [PATCH v3] drm/bridge:anx7625: Update HDCP status at
> > atomic_enable()
> >
> > CAUTION: This email originated from outside of the organization. Please do not
> > click links or open attachments unless you recognize the sender, and know the
> > content is safe.
> >
> >
> > On Fri, Dec 13, 2024 at 10:06:36AM +0000, Xin Ji wrote:
> > > Hi Dmitry, thanks for the review, I made some changes which change
> > > ENABLE to DESIRE in .atomic_disable(), I'll upstream it after testing. Thanks!
> >
> > - Please don't top-post.
> >
> > - You still didn't explain, why do you want to do this change of HDCP
> > status. Could you please provide an explanation before sending the
> > next iteration?
> >
> > >
> > > > -----Original Message-----
> > > > From: Dmitry Baryshkov <dmitry.baryshkov@...aro.org>
> > > > Sent: Thursday, December 12, 2024 5:18 PM
> > > > To: Xin Ji <xji@...logixsemi.com>
> > > > Cc: Andrzej Hajda <andrzej.hajda@...el.com>; Neil Armstrong
> > > > <neil.armstrong@...aro.org>; Robert Foss <rfoss@...nel.org>; Laurent
> > > > Pinchart <Laurent.pinchart@...asonboard.com>; Jonas Karlman
> > > > <jonas@...boo.se>; Jernej Skrabec <jernej.skrabec@...il.com>;
> > > > Maarten Lankhorst <maarten.lankhorst@...ux.intel.com>; Maxime Ripard
> > > > <mripard@...nel.org>; Thomas Zimmermann <tzimmermann@...e.de>;
> > David
> > > > Airlie <airlied@...il.com>; Simona Vetter <simona@...ll.ch>; Bernie
> > > > Liang <bliang@...logixsemi.com>; Qilin Wen <qwen@...logixsemi.com>;
> > > > treapking@...gle.com; dri-devel@...ts.freedesktop.org; linux-
> > > > kernel@...r.kernel.org
> > > > Subject: Re: [PATCH v3] drm/bridge:anx7625: Update HDCP status at
> > > > atomic_enable()
> > > >
> > > > CAUTION: This email originated from outside of the organization.
> > > > Please do not click links or open attachments unless you recognize
> > > > the sender, and know the content is safe.
> > > >
> > > >
> > > > On Thu, Dec 12, 2024 at 01:51:10PM +0800, Xin Ji wrote:
> > > > > When user enabled HDCP feature, userspace will set HDCP content to
> > > > > DRM_MODE_CONTENT_PROTECTION_DESIRED. Next, anx7625 will
> > update
> > > > HDCP
> > > > > content to DRM_MODE_CONTENT_PROTECTION_ENABLED if down
> > stream
> > > > support
> > > > > HDCP feature.
> > > > >
> > > > > However once HDCP content turn to
> > > > DRM_MODE_CONTENT_PROTECTION_ENABLED
> > > > > userspace will not update the HDCP content to
> > > > > DRM_MODE_CONTENT_PROTECTION_UNDESIRED until monitor
> > disconnect.
> > > >
> > > > It seems you've ingored a part of the previous review comment. It's
> > > > the userspace who triggers the ENABLED -> UNDESIRED transition, not
> > > > the kernel side. The change to move HDCP handling to atomic_enable()
> > > > looks fine, the change to disable HDCP is not (unless I misunderstand
> > something).
> > > >
> > > > >
> > > > > So, anx7625 driver move hdcp content value checking from bridge
> > > > > interface .atomic_check() to .atomic_enable(), then update hdcp
> > > > > content according from currently HDCP status. And also disabled
> > > > > HDCP in bridge interface .atomic_disable().
> > > > >
> > > > > Signed-off-by: Xin Ji <xji@...logixsemi.com>
> > > > > ---
> > > > > drivers/gpu/drm/bridge/analogix/anx7625.c | 74
> > > > > ++++++++++++++---------
> > > > > 1 file changed, 46 insertions(+), 28 deletions(-)
> > > > >
> > > > > diff --git a/drivers/gpu/drm/bridge/analogix/anx7625.c
> > > > > b/drivers/gpu/drm/bridge/analogix/anx7625.c
> > > > > index a2675b121fe4..f96ce5665e8d 100644
> > > > > --- a/drivers/gpu/drm/bridge/analogix/anx7625.c
> > > > > +++ b/drivers/gpu/drm/bridge/analogix/anx7625.c
> > > > > @@ -861,6 +861,22 @@ static int anx7625_hdcp_disable(struct
> > > > > anx7625_data
> > > > *ctx)
> > > > > TX_HDCP_CTRL0, ~HARD_AUTH_EN &
> > > > > 0xFF); }
> > > > >
> > > > > +static void anx7625_hdcp_disable_and_update_cp(struct
> > > > > +anx7625_data
> > > > > +*ctx) {
> > > > > + struct device *dev = ctx->dev;
> > > > > +
> > > > > + if (!ctx->connector)
> > > > > + return;
> > > > > +
> > > > > + anx7625_hdcp_disable(ctx);
> > > > > +
> > > > > + ctx->hdcp_cp = DRM_MODE_CONTENT_PROTECTION_UNDESIRED;
> > > > > + drm_hdcp_update_content_protection(ctx->connector,
> > > > > + ctx->hdcp_cp);
> > > > > +
> > > > > + dev_dbg(dev, "update CP to UNDESIRE\n"); }
> > > > > +
> > > > > static int anx7625_hdcp_enable(struct anx7625_data *ctx) {
> > > > > u8 bcap;
> > > > > @@ -2149,34 +2165,6 @@ static int
> > > > > anx7625_connector_atomic_check(struct
> > > > anx7625_data *ctx,
> > > > > if (cp == ctx->hdcp_cp)
> > > > > return 0;
> > > > >
> > > > > - if (cp == DRM_MODE_CONTENT_PROTECTION_DESIRED) {
> > > > > - if (ctx->dp_en) {
> > > > > - dev_dbg(dev, "enable HDCP\n");
> > > > > - anx7625_hdcp_enable(ctx);
> > > > > -
> > > > > - queue_delayed_work(ctx->hdcp_workqueue,
> > > > > - &ctx->hdcp_work,
> > > > > - msecs_to_jiffies(2000));
> > > > > - }
> > > > > - }
> > > > > -
> > > > > - if (cp == DRM_MODE_CONTENT_PROTECTION_UNDESIRED) {
> > > > > - if (ctx->hdcp_cp !=
> > DRM_MODE_CONTENT_PROTECTION_ENABLED) {
> > > > > - dev_err(dev, "current CP is not ENABLED\n");
> > > > > - return -EINVAL;
> > > > > - }
> > > > > - anx7625_hdcp_disable(ctx);
> > > > > - ctx->hdcp_cp = DRM_MODE_CONTENT_PROTECTION_UNDESIRED;
> > > > > - drm_hdcp_update_content_protection(ctx->connector,
> > > > > - ctx->hdcp_cp);
> > > > > - dev_dbg(dev, "update CP to UNDESIRE\n");
> > > > > - }
> > > > > -
> > > > > - if (cp == DRM_MODE_CONTENT_PROTECTION_ENABLED) {
> > > > > - dev_err(dev, "Userspace illegal set to PROTECTION ENABLE\n");
> > > > > - return -EINVAL;
> > > > > - }
> > > > > -
> > > > > return 0;
> > > > > }
> > > > >
> > > > > @@ -2425,6 +2413,8 @@ static void
> > > > > anx7625_bridge_atomic_enable(struct
> > > > drm_bridge *bridge,
> > > > > struct anx7625_data *ctx = bridge_to_anx7625(bridge);
> > > > > struct device *dev = ctx->dev;
> > > > > struct drm_connector *connector;
> > > > > + struct drm_connector_state *conn_state;
> > > > > + int cp;
> > > > >
> > > > > dev_dbg(dev, "drm atomic enable\n");
> > > > >
> > > > > @@ -2439,6 +2429,32 @@ static void
> > > > > anx7625_bridge_atomic_enable(struct
> > > > drm_bridge *bridge,
> > > > > _anx7625_hpd_polling(ctx, 5000 * 100);
> > > > >
> > > > > anx7625_dp_start(ctx);
> > > > > +
> > > > > + conn_state =
> > > > > + drm_atomic_get_new_connector_state(state->base.state,
> > > > > + connector);
> > > > > +
> > > > > + if (WARN_ON(!conn_state))
> > > > > + return;
> > > > > +
> > > > > + cp = conn_state->content_protection;
> > > > > + if (cp == DRM_MODE_CONTENT_PROTECTION_DESIRED) {
> > > > > + if (ctx->dp_en) {
> > > > > + dev_dbg(dev, "enable HDCP\n");
> > > > > + anx7625_hdcp_enable(ctx);
> > > > > +
> > > > > + queue_delayed_work(ctx->hdcp_workqueue,
> > > > > + &ctx->hdcp_work,
> > > > > + msecs_to_jiffies(2000));
> > > > > + }
> > > > > + }
> > > > > +
> > > > > + if (cp == DRM_MODE_CONTENT_PROTECTION_UNDESIRED) {
> > > > > + if (ctx->hdcp_cp !=
> > DRM_MODE_CONTENT_PROTECTION_ENABLED) {
> > > > > + dev_err(dev, "current CP is not ENABLED\n");
> > > > > + return;
> > > > > + }
> > > > > +
> > > > > + anx7625_hdcp_disable_and_update_cp(ctx);
> > > > > + }
> > > > > }
> > > > >
> > > > > static void anx7625_bridge_atomic_disable(struct drm_bridge
> > > > > *bridge, @@ -2449,6 +2465,8 @@ static void
> > > > > anx7625_bridge_atomic_disable(struct
> > > > > drm_bridge *bridge,
> > > > >
> > > > > dev_dbg(dev, "drm atomic disable\n");
> > > > >
> > > > > + anx7625_hdcp_disable_and_update_cp(ctx);
> > > > > +
> > > > > ctx->connector = NULL;
> > > > > anx7625_dp_stop(ctx);
> > > > >
> > > > > --
> > > > > 2.25.1
> > > > >
> > > >
> > > > --
> > > > With best wishes
> > > > Dmitry
> >
> > --
> > With best wishes
> > Dmitry
--
With best wishes
Dmitry
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