From: Douglas Anderson <dianders@chromium.org> To: Andrzej Hajda <a.hajda@samsung.com>, Neil Armstrong <narmstrong@baylibre.com>, Laurent Pinchart <Laurent.pinchart@ideasonboard.com>, Jonas Karlman <jonas@kwiboo.se>, Jernej Skrabec <jernej.skrabec@siol.net>, Sam Ravnborg <sam@ravnborg.org>, Wolfram Sang <wsa@kernel.org> Cc: Stephen Boyd <swboyd@chromium.org>, robdclark@chromium.org, Maarten Lankhorst <maarten.lankhorst@linux.intel.com>, Stanislav Lisovskiy <stanislav.lisovskiy@intel.com>, Steev Klimaszewski <steev@kali.org>, Bjorn Andersson <bjorn.andersson@linaro.org>, linux-arm-msm@vger.kernel.org, Linus W <linus.walleij@linaro.org>, Douglas Anderson <dianders@chromium.org>, Laurent Pinchart <laurent.pinchart@ideasonboard.com>, Daniel Vetter <daniel@ffwll.ch>, David Airlie <airlied@linux.ie>, Thierry Reding <thierry.reding@gmail.com>, dri-devel@lists.freedesktop.org, linux-kernel@vger.kernel.org Subject: [PATCH v4 27/27] drm/panel: panel-simple: Prepare/unprepare are refcounted, not forced Date: Fri, 16 Apr 2021 15:39:50 -0700 [thread overview] Message-ID: <20210416153909.v4.27.I502f2a92ddd36c3d28d014dd75e170c2d405a0a5@changeid> (raw) In-Reply-To: <20210416223950.3586967-1-dianders@chromium.org> Historically simple-panel had code to make sure that if prepare() was called on an already-prepared panel that it was a no-op. Similarly if unprepare() was called on an already-unprepared panel it was also a no-op. Essentially it means that these functions always "forced" the value to be whatever the caller wanted it to be. You can see that the forcing behavior dates back at least as far as 2014 by looking at commit 613a633e7a56 ("drm/panel: simple: Add proper definition for prepare and unprepare"). Apparently the code supporting the historical behavior may not be needed [1] and prepare() / unprepare() are supposed to be balanced. Let's try removing it and see if anyone breaks! If they do then we can have a debate about whether we should change that code or revert this patch. :-) If nobody breaks then we've nicely saved a few lines of code and some complexity. [1] https://lore.kernel.org/r/YHePsQgqOau1V5lD@pendragon.ideasonboard.com Suggested-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com> Signed-off-by: Douglas Anderson <dianders@chromium.org> --- (no changes since v1) drivers/gpu/drm/panel/panel-simple.c | 14 -------------- 1 file changed, 14 deletions(-) diff --git a/drivers/gpu/drm/panel/panel-simple.c b/drivers/gpu/drm/panel/panel-simple.c index 5a2953c4ca44..a2c3008af7e5 100644 --- a/drivers/gpu/drm/panel/panel-simple.c +++ b/drivers/gpu/drm/panel/panel-simple.c @@ -176,8 +176,6 @@ struct panel_simple { bool enabled; bool no_hpd; - bool prepared; - ktime_t prepared_time; ktime_t unprepared_time; @@ -355,18 +353,12 @@ static int panel_simple_suspend(struct device *dev) static int panel_simple_unprepare(struct drm_panel *panel) { - struct panel_simple *p = to_panel_simple(panel); int ret; - /* Unpreparing when already unprepared is a no-op */ - if (!p->prepared) - return 0; - pm_runtime_mark_last_busy(panel->dev); ret = pm_runtime_put_autosuspend(panel->dev); if (ret < 0) return ret; - p->prepared = false; return 0; } @@ -475,18 +467,12 @@ static int panel_simple_prepare(struct drm_panel *panel) struct panel_simple *p = to_panel_simple(panel); int ret; - /* Preparing when already prepared is a no-op */ - if (p->prepared) - return 0; - ret = pm_runtime_get_sync(panel->dev); if (ret < 0) { pm_runtime_put_autosuspend(panel->dev); return ret; } - p->prepared = true; - return 0; } -- 2.31.1.368.gbe11c130af-goog
WARNING: multiple messages have this Message-ID (diff)
From: Douglas Anderson <dianders@chromium.org> To: Andrzej Hajda <a.hajda@samsung.com>, Neil Armstrong <narmstrong@baylibre.com>, Laurent Pinchart <Laurent.pinchart@ideasonboard.com>, Jonas Karlman <jonas@kwiboo.se>, Jernej Skrabec <jernej.skrabec@siol.net>, Sam Ravnborg <sam@ravnborg.org>, Wolfram Sang <wsa@kernel.org> Cc: robdclark@chromium.org, dri-devel@lists.freedesktop.org, David Airlie <airlied@linux.ie>, linux-arm-msm@vger.kernel.org, Douglas Anderson <dianders@chromium.org>, Steev Klimaszewski <steev@kali.org>, Bjorn Andersson <bjorn.andersson@linaro.org>, Stanislav Lisovskiy <stanislav.lisovskiy@intel.com>, Thierry Reding <thierry.reding@gmail.com>, Laurent Pinchart <laurent.pinchart@ideasonboard.com>, Stephen Boyd <swboyd@chromium.org>, linux-kernel@vger.kernel.org Subject: [PATCH v4 27/27] drm/panel: panel-simple: Prepare/unprepare are refcounted, not forced Date: Fri, 16 Apr 2021 15:39:50 -0700 [thread overview] Message-ID: <20210416153909.v4.27.I502f2a92ddd36c3d28d014dd75e170c2d405a0a5@changeid> (raw) In-Reply-To: <20210416223950.3586967-1-dianders@chromium.org> Historically simple-panel had code to make sure that if prepare() was called on an already-prepared panel that it was a no-op. Similarly if unprepare() was called on an already-unprepared panel it was also a no-op. Essentially it means that these functions always "forced" the value to be whatever the caller wanted it to be. You can see that the forcing behavior dates back at least as far as 2014 by looking at commit 613a633e7a56 ("drm/panel: simple: Add proper definition for prepare and unprepare"). Apparently the code supporting the historical behavior may not be needed [1] and prepare() / unprepare() are supposed to be balanced. Let's try removing it and see if anyone breaks! If they do then we can have a debate about whether we should change that code or revert this patch. :-) If nobody breaks then we've nicely saved a few lines of code and some complexity. [1] https://lore.kernel.org/r/YHePsQgqOau1V5lD@pendragon.ideasonboard.com Suggested-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com> Signed-off-by: Douglas Anderson <dianders@chromium.org> --- (no changes since v1) drivers/gpu/drm/panel/panel-simple.c | 14 -------------- 1 file changed, 14 deletions(-) diff --git a/drivers/gpu/drm/panel/panel-simple.c b/drivers/gpu/drm/panel/panel-simple.c index 5a2953c4ca44..a2c3008af7e5 100644 --- a/drivers/gpu/drm/panel/panel-simple.c +++ b/drivers/gpu/drm/panel/panel-simple.c @@ -176,8 +176,6 @@ struct panel_simple { bool enabled; bool no_hpd; - bool prepared; - ktime_t prepared_time; ktime_t unprepared_time; @@ -355,18 +353,12 @@ static int panel_simple_suspend(struct device *dev) static int panel_simple_unprepare(struct drm_panel *panel) { - struct panel_simple *p = to_panel_simple(panel); int ret; - /* Unpreparing when already unprepared is a no-op */ - if (!p->prepared) - return 0; - pm_runtime_mark_last_busy(panel->dev); ret = pm_runtime_put_autosuspend(panel->dev); if (ret < 0) return ret; - p->prepared = false; return 0; } @@ -475,18 +467,12 @@ static int panel_simple_prepare(struct drm_panel *panel) struct panel_simple *p = to_panel_simple(panel); int ret; - /* Preparing when already prepared is a no-op */ - if (p->prepared) - return 0; - ret = pm_runtime_get_sync(panel->dev); if (ret < 0) { pm_runtime_put_autosuspend(panel->dev); return ret; } - p->prepared = true; - return 0; } -- 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:[~2021-04-16 22:41 UTC|newest] Thread overview: 102+ 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 ` 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 ` 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 ` 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 ` Douglas Anderson 2021-04-16 22:39 ` [PATCH v4 04/27] drm/bridge: ti-sn65dsi86: Reorder remove() Douglas Anderson 2021-04-16 22:39 ` 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 ` 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 ` 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 ` Douglas Anderson 2021-04-16 22:39 ` [PATCH v4 08/27] drm/bridge: ti-sn65dsi86: Rename the main driver data structure Douglas Anderson 2021-04-16 22:39 ` Douglas Anderson 2021-04-23 14:28 ` Bjorn Andersson 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 2021-04-16 22:39 ` Douglas Anderson 2021-04-23 14:30 ` Bjorn Andersson 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 2021-04-16 22:39 ` Douglas Anderson 2021-04-23 14:35 ` Bjorn Andersson 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 2021-04-16 22:39 ` Douglas Anderson 2021-04-23 14:38 ` Bjorn Andersson 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 2021-04-16 22:39 ` Douglas Anderson 2021-04-23 14:38 ` Bjorn Andersson 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 2021-04-16 22:39 ` Douglas Anderson 2021-04-23 14:39 ` Bjorn Andersson 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 2021-04-16 22:39 ` Douglas Anderson 2021-04-23 14:41 ` Bjorn Andersson 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 2021-04-16 22:39 ` Douglas Anderson 2021-04-17 2:31 ` kernel test robot 2021-04-17 2:31 ` kernel test robot 2021-04-19 15:43 ` Doug Anderson 2021-04-19 15:43 ` Doug Anderson 2021-04-23 14:49 ` Bjorn Andersson 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 2021-04-16 22:39 ` Douglas Anderson 2021-04-23 14:50 ` Bjorn Andersson 2021-04-23 14:50 ` Bjorn Andersson 2021-04-16 22:39 ` [PATCH v4 17/27] drm/bridge: ti-sn65dsi86: Use pm_runtime autosuspend Douglas Anderson 2021-04-16 22:39 ` Douglas Anderson 2021-04-23 14:51 ` Bjorn Andersson 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 2021-04-16 22:39 ` Douglas Anderson 2021-04-23 14:51 ` Bjorn Andersson 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 2021-04-16 22:39 ` Douglas Anderson 2021-04-23 14:56 ` Bjorn Andersson 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 2021-04-16 22:39 ` Douglas Anderson 2021-04-23 14:59 ` Bjorn Andersson 2021-04-23 14:59 ` Bjorn Andersson 2021-04-16 22:39 ` [PATCH v4 21/27] i2c: i2c-core-of: Fix corner case of finding adapter by node Douglas Anderson 2021-04-23 15:12 ` 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 2021-04-16 22:39 ` Douglas Anderson 2021-04-23 15:15 ` Bjorn Andersson 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 2021-04-16 22:39 ` Douglas Anderson 2021-04-23 15:16 ` Bjorn Andersson 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 2021-04-16 22:39 ` Douglas Anderson 2021-04-23 16:12 ` Bjorn Andersson 2021-04-23 16:12 ` Bjorn Andersson 2021-04-23 16:30 ` Doug Anderson 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 2021-04-16 22:39 ` Douglas Anderson 2021-04-23 16:13 ` Bjorn Andersson 2021-04-23 16:13 ` Bjorn Andersson 2021-04-16 22:39 ` [PATCH v4 26/27] arm64: dts: qcom: Link the panel to the bridge's DDC bus Douglas Anderson 2021-04-23 16:16 ` Bjorn Andersson 2021-04-16 22:39 ` Douglas Anderson [this message] 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 16:16 ` Bjorn Andersson 2021-04-23 16:46 ` Doug Anderson 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 2021-04-20 16:42 ` 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=20210416153909.v4.27.I502f2a92ddd36c3d28d014dd75e170c2d405a0a5@changeid \ --to=dianders@chromium.org \ --cc=Laurent.pinchart@ideasonboard.com \ --cc=a.hajda@samsung.com \ --cc=airlied@linux.ie \ --cc=bjorn.andersson@linaro.org \ --cc=daniel@ffwll.ch \ --cc=dri-devel@lists.freedesktop.org \ --cc=jernej.skrabec@siol.net \ --cc=jonas@kwiboo.se \ --cc=linus.walleij@linaro.org \ --cc=linux-arm-msm@vger.kernel.org \ --cc=linux-kernel@vger.kernel.org \ --cc=maarten.lankhorst@linux.intel.com \ --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: linkBe sure your reply has a Subject: header at the top and a blank line before the message body.
This is an external index of several public inboxes, see mirroring instructions on how to clone and mirror all data and code used by this external index.