From: Maxime Ripard <maxime@cerno.tech>
To: Kevin Tang <kevin3.tang@gmail.com>
Cc: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>,
Sean Paul <sean@poorly.run>, David Airlie <airlied@linux.ie>,
Daniel Vetter <daniel@ffwll.ch>, Rob Herring <robh+dt@kernel.org>,
Mark Rutland <mark.rutland@arm.com>,
Orson Zhai <orsonzhai@gmail.com>,
Chunyan Zhang <zhang.lyra@gmail.com>,
"Linux-Kernel@Vger. Kernel. Org" <linux-kernel@vger.kernel.org>,
ML dri-devel <dri-devel@lists.freedesktop.org>,
devicetree@vger.kernel.org
Subject: Re: [PATCH v4 4/6] drm/sprd: add Unisoc's drm display controller driver
Date: Thu, 15 Apr 2021 11:03:12 +0200 [thread overview]
Message-ID: <20210415090312.md6exuuv2y4mblxn@gilmour> (raw)
In-Reply-To: <CAFPSGXYZPoM45vF_HcjMBcO_Ek-UJZw7F+Q0Of-gWZxvVaPQjg@mail.gmail.com>
[-- Attachment #1: Type: text/plain, Size: 2683 bytes --]
Hi,
On Thu, Apr 15, 2021 at 08:18:52AM +0800, Kevin Tang wrote:
> Maxime Ripard <maxime@cerno.tech> 于2021年3月24日周三 下午7:10写道:
> > > +static struct sprd_dpu *sprd_crtc_init(struct drm_device *drm,
> > > + struct drm_plane *primary)
> > > +{
> > > + struct device_node *port;
> > > + struct sprd_dpu *dpu;
> > > +
> > > + /*
> > > + * set crtc port so that drm_of_find_possible_crtcs call works
> > > + */
> > > + port = of_parse_phandle(drm->dev->of_node, "ports", 0);
> > > + if (!port) {
> > > + drm_err(drm, "find 'ports' phandle of %s failed\n",
> > > + drm->dev->of_node->full_name);
> > > + return ERR_PTR(-EINVAL);
> > > + }
> > > + of_node_put(port);
> >
> > The YAML binding should already make sure that your binding is sane, and
> > if you still get a DT that doesn't follow it, you have a whole lot of
> > other issues than whether ports is there :)
> >
> > > + dpu = drmm_crtc_alloc_with_planes(drm, struct sprd_dpu, base,
> > > + primary, NULL,
> > > + &sprd_crtc_funcs, NULL);
> > > + if (IS_ERR(dpu)) {
> > > + drm_err(drm, "failed to init crtc.\n");
> > > + return dpu;
> > > + }
> > > +
> > > + dpu->base.port = port;
> >
> > But you're still referencing it here, while you called of_node_put on it
> > already? You should only call it once you're done with it.
>
> of_node_put should be called after done with it, this maybe indeed be a bug.
> i will fix it.
> >
> >
> > I'm not really sure why you would need drm_of_find_possible_crtcs to
> > work then if you don't follow the OF-Graph bindings.
>
> it scan all endports of encoder, if a matching crtc is found by
> OF-Graph bindings
> and then genarate the crtc mask, here is description:
> 41 /**
> 42 * drm_of_find_possible_crtcs - find the possible CRTCs for an encoder port
> 43 * @dev: DRM device
> 44 * @port: encoder port to scan for endpoints
> 45 *
> 46 * Scan all endpoints attached to a port, locate their attached CRTCs,
> 47 * and generate the DRM mask of CRTCs which may be attached to this
> 48 * encoder.
> 49 *
> if we don't follow the OF-Graph bindings, crtc can't attched to encoder.
Yeah, what I'm actually confused about is why you would need the
of_parse_phandle call. You usually call drm_of_find_possible_crtcs with
the encoder device node, so from your MIPI-DSI driver in your case, and
with it's device->of_node pointer and it should work perfectly fine?
Maxime
[-- Attachment #2: signature.asc --]
[-- Type: application/pgp-signature, Size: 228 bytes --]
next prev parent reply other threads:[~2021-04-15 9:03 UTC|newest]
Thread overview: 27+ messages / expand[flat|nested] mbox.gz Atom feed top
2021-02-22 13:28 [PATCH v4 0/6] Add Unisoc's drm kms module Kevin Tang
2021-02-22 13:28 ` [PATCH v4 1/6] dt-bindings: display: add Unisoc's drm master bindings Kevin Tang
2021-02-22 13:28 ` [PATCH v4 2/6] drm/sprd: add Unisoc's drm kms master Kevin Tang
2021-02-22 20:55 ` Orson Zhai
2021-03-24 10:53 ` Maxime Ripard
2021-04-08 10:21 ` Thomas Zimmermann
[not found] ` <CAFPSGXZ2o9YRAMax3ZeiyQ5bMtqOsSODMW8V7dXHZSD3gyzbQw@mail.gmail.com>
2021-04-09 13:57 ` Thomas Zimmermann
2021-02-22 13:28 ` [PATCH v4 3/6] dt-bindings: display: add Unisoc's dpu bindings Kevin Tang
2021-02-22 13:28 ` [PATCH v4 4/6] drm/sprd: add Unisoc's drm display controller driver Kevin Tang
2021-03-24 11:10 ` Maxime Ripard
[not found] ` <CAFPSGXZ3DjKt87Kc=wc9YKVzTjkQ38Ok6HnHm+VEdqXyHv54Eg@mail.gmail.com>
2021-04-07 10:45 ` Maxime Ripard
2021-04-08 3:05 ` Chunyan Zhang
[not found] ` <CAFPSGXa3xsxmfVquN_pTyBJ4+kL4jQAj6sK+86G3SA2OhB7Jtg@mail.gmail.com>
2021-04-15 9:09 ` Maxime Ripard
2021-04-15 0:18 ` Kevin Tang
2021-04-15 9:03 ` Maxime Ripard [this message]
2021-04-18 23:01 ` Kevin Tang
2021-04-21 10:00 ` Maxime Ripard
2021-04-08 10:53 ` Thomas Zimmermann
2021-02-22 13:28 ` [PATCH v4 5/6] dt-bindings: display: add Unisoc's mipi dsi controller bindings Kevin Tang
2021-03-24 11:13 ` Maxime Ripard
[not found] ` <CAFPSGXah3gKKHXhukRAPT=RjQZTnvDznG+619+8tah-hfFrUzA@mail.gmail.com>
2021-04-07 10:46 ` Maxime Ripard
[not found] ` <CAFPSGXaQKeKMKC7MGXhxQErB_yh_eE8khk1hOrjHnuOH20Gg4Q@mail.gmail.com>
2021-04-15 8:42 ` Maxime Ripard
2021-04-18 16:33 ` Kevin Tang
2021-04-21 9:38 ` Maxime Ripard
2021-02-22 13:28 ` [PATCH v4 6/6] drm/sprd: add Unisoc's drm mipi dsi&dphy driver Kevin Tang
[not found] ` <20210324112745.n76qhrbhzyfunmkd@gilmour>
[not found] ` <CAFPSGXYK0Hi2-eYkukO2pNhHrJVZ=f79sj_hjXnGBZ_meVmkFg@mail.gmail.com>
2021-04-07 10:48 ` Maxime Ripard
2021-04-15 0:19 ` Kevin Tang
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=20210415090312.md6exuuv2y4mblxn@gilmour \
--to=maxime@cerno.tech \
--cc=airlied@linux.ie \
--cc=daniel@ffwll.ch \
--cc=devicetree@vger.kernel.org \
--cc=dri-devel@lists.freedesktop.org \
--cc=kevin3.tang@gmail.com \
--cc=linux-kernel@vger.kernel.org \
--cc=maarten.lankhorst@linux.intel.com \
--cc=mark.rutland@arm.com \
--cc=orsonzhai@gmail.com \
--cc=robh+dt@kernel.org \
--cc=sean@poorly.run \
--cc=zhang.lyra@gmail.com \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).