From: Bjorn Andersson <bjorn.andersson@linaro.org>
To: Douglas Anderson <dianders@chromium.org>
Cc: robdclark@chromium.org,
Stanislav Lisovskiy <stanislav.lisovskiy@intel.com>,
Jernej Skrabec <jernej.skrabec@siol.net>,
dri-devel@lists.freedesktop.org, Jonas Karlman <jonas@kwiboo.se>,
David Airlie <airlied@linux.ie>,
linux-arm-msm@vger.kernel.org,
Neil Armstrong <narmstrong@baylibre.com>,
linux-kernel@vger.kernel.org, Steev Klimaszewski <steev@kali.org>,
Stephen Boyd <swboyd@chromium.org>, Wolfram Sang <wsa@kernel.org>,
Andrzej Hajda <a.hajda@samsung.com>,
Thierry Reding <thierry.reding@gmail.com>,
Laurent Pinchart <Laurent.pinchart@ideasonboard.com>,
Sam Ravnborg <sam@ravnborg.org>
Subject: Re: [PATCH v4 16/27] drm/panel: panel-simple: Get rid of hacky HPD chicken-and-egg code
Date: Fri, 23 Apr 2021 09:50:47 -0500 [thread overview]
Message-ID: <YILex5oaMUQy5zs/@builder.lan> (raw)
In-Reply-To: <20210416153909.v4.16.I40eeedc23459d1e3fc96fa6cdad775d88c6e706c@changeid>
On Fri 16 Apr 17:39 CDT 2021, Douglas Anderson wrote:
> When I added support for the hpd-gpio to simple-panel in commit
> 48834e6084f1 ("drm/panel-simple: Support hpd-gpios for delaying
> prepare()"), I added a special case to handle a circular dependency I
> was running into on the ti-sn65dsi86 bridge chip. On my board the
> hpd-gpio is actually provided by the bridge chip. That was causing
> some circular dependency problems that I had to work around by getting
> the hpd-gpio late.
>
> I've now reorganized the ti-sn65dsi86 bridge chip driver to be a
> collection of sub-drivers. Now the GPIO part can probe separately and
> that breaks the chain. Let's get rid of the old code to clean things
> up.
>
Reviewed-by: Bjorn Andersson <bjorn.andersson@linaro.org>
Regards,
Bjorn
> Signed-off-by: Douglas Anderson <dianders@chromium.org>
> ---
>
> (no changes since v1)
>
> drivers/gpu/drm/panel/panel-simple.c | 24 +++++-------------------
> 1 file changed, 5 insertions(+), 19 deletions(-)
>
> diff --git a/drivers/gpu/drm/panel/panel-simple.c b/drivers/gpu/drm/panel/panel-simple.c
> index 6b22872b3281..90a17ca79d06 100644
> --- a/drivers/gpu/drm/panel/panel-simple.c
> +++ b/drivers/gpu/drm/panel/panel-simple.c
> @@ -366,8 +366,7 @@ static int panel_simple_unprepare(struct drm_panel *panel)
> return 0;
> }
>
> -static int panel_simple_get_hpd_gpio(struct device *dev,
> - struct panel_simple *p, bool from_probe)
> +static int panel_simple_get_hpd_gpio(struct device *dev, struct panel_simple *p)
> {
> int err;
>
> @@ -375,17 +374,10 @@ static int panel_simple_get_hpd_gpio(struct device *dev,
> if (IS_ERR(p->hpd_gpio)) {
> err = PTR_ERR(p->hpd_gpio);
>
> - /*
> - * If we're called from probe we won't consider '-EPROBE_DEFER'
> - * to be an error--we'll leave the error code in "hpd_gpio".
> - * When we try to use it we'll try again. This allows for
> - * circular dependencies where the component providing the
> - * hpd gpio needs the panel to init before probing.
> - */
> - if (err != -EPROBE_DEFER || !from_probe) {
> + if (err != -EPROBE_DEFER)
> dev_err(dev, "failed to get 'hpd' GPIO: %d\n", err);
> - return err;
> - }
> +
> + return err;
> }
>
> return 0;
> @@ -416,12 +408,6 @@ static int panel_simple_prepare_once(struct panel_simple *p)
> msleep(delay);
>
> if (p->hpd_gpio) {
> - if (IS_ERR(p->hpd_gpio)) {
> - err = panel_simple_get_hpd_gpio(dev, p, false);
> - if (err)
> - goto error;
> - }
> -
> if (p->desc->delay.hpd_absent_delay)
> hpd_wait_us = p->desc->delay.hpd_absent_delay * 1000UL;
> else
> @@ -682,7 +668,7 @@ static int panel_simple_probe(struct device *dev, const struct panel_desc *desc)
>
> panel->no_hpd = of_property_read_bool(dev->of_node, "no-hpd");
> if (!panel->no_hpd) {
> - err = panel_simple_get_hpd_gpio(dev, panel, true);
> + err = panel_simple_get_hpd_gpio(dev, panel);
> if (err)
> return err;
> }
> --
> 2.31.1.368.gbe11c130af-goog
>
_______________________________________________
dri-devel mailing list
dri-devel@lists.freedesktop.org
https://lists.freedesktop.org/mailman/listinfo/dri-devel
next prev parent reply other threads:[~2021-04-23 14:50 UTC|newest]
Thread overview: 49+ messages / expand[flat|nested] mbox.gz Atom feed top
2021-04-16 22:39 [PATCH v4 00/27] drm: Fix EDID reading on ti-sn65dsi86; solve some chicken-and-egg problems Douglas Anderson
2021-04-16 22:39 ` [PATCH v4 01/27] drm/bridge: Fix the stop condition of drm_bridge_chain_pre_enable() Douglas Anderson
2021-04-16 22:39 ` [PATCH v4 02/27] drm/bridge: ti-sn65dsi86: Simplify refclk handling Douglas Anderson
2021-04-16 22:39 ` [PATCH v4 03/27] drm/bridge: ti-sn65dsi86: Remove incorrectly tagged kerneldoc comment Douglas Anderson
2021-04-16 22:39 ` [PATCH v4 04/27] drm/bridge: ti-sn65dsi86: Reorder remove() Douglas Anderson
2021-04-16 22:39 ` [PATCH v4 05/27] drm/bridge: ti-sn65dsi86: Move drm_panel_unprepare() to post_disable() Douglas Anderson
2021-04-16 22:39 ` [PATCH v4 06/27] drm/bridge: ti-sn65dsi86: Get rid of the useless detect() function Douglas Anderson
2021-04-16 22:39 ` [PATCH v4 07/27] drm/panel: panel-simple: Use runtime pm to avoid excessive unprepare / prepare Douglas Anderson
2021-04-16 22:39 ` [PATCH v4 08/27] drm/bridge: ti-sn65dsi86: Rename the main driver data structure Douglas Anderson
2021-04-23 14:28 ` Bjorn Andersson
2021-04-16 22:39 ` [PATCH v4 09/27] drm/bridge: ti-sn65dsi86: More renames in prep for sub-devices Douglas Anderson
2021-04-23 14:30 ` Bjorn Andersson
2021-04-16 22:39 ` [PATCH v4 10/27] drm/bridge: ti-sn65dsi86: Clean debugfs code Douglas Anderson
2021-04-23 14:35 ` Bjorn Andersson
2021-04-16 22:39 ` [PATCH v4 11/27] drm/bridge: ti-sn65dsi86: Add local var for "dev" to simplify probe Douglas Anderson
2021-04-23 14:38 ` Bjorn Andersson
2021-04-16 22:39 ` [PATCH v4 12/27] drm/bridge: ti-sn65dsi86: Cleanup managing of drvdata Douglas Anderson
2021-04-23 14:38 ` Bjorn Andersson
2021-04-16 22:39 ` [PATCH v4 13/27] drm/bridge: ti-sn65dsi86: Use devm to do our runtime_disable Douglas Anderson
2021-04-23 14:39 ` Bjorn Andersson
2021-04-16 22:39 ` [PATCH v4 14/27] drm/bridge: ti-sn65dsi86: Move all the chip-related init to the start Douglas Anderson
2021-04-23 14:41 ` Bjorn Andersson
2021-04-16 22:39 ` [PATCH v4 15/27] drm/bridge: ti-sn65dsi86: Break GPIO and MIPI-to-eDP bridge into sub-drivers Douglas Anderson
2021-04-17 2:31 ` kernel test robot
2021-04-19 15:43 ` Doug Anderson
2021-04-23 14:49 ` Bjorn Andersson
2021-04-16 22:39 ` [PATCH v4 16/27] drm/panel: panel-simple: Get rid of hacky HPD chicken-and-egg code Douglas Anderson
2021-04-23 14:50 ` Bjorn Andersson [this message]
2021-04-16 22:39 ` [PATCH v4 17/27] drm/bridge: ti-sn65dsi86: Use pm_runtime autosuspend Douglas Anderson
2021-04-23 14:51 ` Bjorn Andersson
2021-04-16 22:39 ` [PATCH v4 18/27] drm/bridge: ti-sn65dsi86: Code motion of refclk management functions Douglas Anderson
2021-04-23 14:51 ` Bjorn Andersson
2021-04-16 22:39 ` [PATCH v4 19/27] drm/bridge: ti-sn65dsi86: If refclk, DP AUX can happen w/out pre-enable Douglas Anderson
2021-04-23 14:56 ` Bjorn Andersson
2021-04-16 22:39 ` [PATCH v4 20/27] drm/bridge: ti-sn65dsi86: Promote the AUX channel to its own sub-dev Douglas Anderson
2021-04-23 14:59 ` Bjorn Andersson
2021-04-16 22:39 ` [PATCH v4 22/27] drm/panel: panel-simple: Remove extra call: drm_connector_update_edid_property() Douglas Anderson
2021-04-23 15:15 ` Bjorn Andersson
2021-04-16 22:39 ` [PATCH v4 23/27] drm/panel: panel-simple: Power the panel when reading the EDID Douglas Anderson
2021-04-23 15:16 ` Bjorn Andersson
2021-04-16 22:39 ` [PATCH v4 24/27] drm/panel: panel-simple: Cache the EDID as long as we retain power Douglas Anderson
2021-04-23 16:12 ` Bjorn Andersson
2021-04-23 16:30 ` Doug Anderson
2021-04-16 22:39 ` [PATCH v4 25/27] drm/bridge: ti-sn65dsi86: Don't read EDID blob over DDC Douglas Anderson
2021-04-23 16:13 ` Bjorn Andersson
2021-04-16 22:39 ` [PATCH v4 27/27] drm/panel: panel-simple: Prepare/unprepare are refcounted, not forced Douglas Anderson
2021-04-23 16:16 ` Bjorn Andersson
2021-04-23 16:46 ` Doug Anderson
2021-04-20 16:42 ` [PATCH v4 00/27] drm: Fix EDID reading on ti-sn65dsi86; solve some chicken-and-egg problems Doug Anderson
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=YILex5oaMUQy5zs/@builder.lan \
--to=bjorn.andersson@linaro.org \
--cc=Laurent.pinchart@ideasonboard.com \
--cc=a.hajda@samsung.com \
--cc=airlied@linux.ie \
--cc=dianders@chromium.org \
--cc=dri-devel@lists.freedesktop.org \
--cc=jernej.skrabec@siol.net \
--cc=jonas@kwiboo.se \
--cc=linux-arm-msm@vger.kernel.org \
--cc=linux-kernel@vger.kernel.org \
--cc=narmstrong@baylibre.com \
--cc=robdclark@chromium.org \
--cc=sam@ravnborg.org \
--cc=stanislav.lisovskiy@intel.com \
--cc=steev@kali.org \
--cc=swboyd@chromium.org \
--cc=thierry.reding@gmail.com \
--cc=wsa@kernel.org \
/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).