linux-kernel - [RFT PATCH v2 05/48] drm/panel: boe-tv101wum-nl6: Don't call unprepare+disable at shutdown/remove

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Message-ID: <20240503143327.RFT.v2.5.I5bd120aa0b7d17a1149ea43cc4852492834058c0@changeid>
Date: Fri,  3 May 2024 14:32:46 -0700
From: Douglas Anderson <dianders@...omium.org>
To: dri-devel@...ts.freedesktop.org,
	Maxime Ripard <mripard@...nel.org>
Cc: Linus Walleij <linus.walleij@...aro.org>,
	Chris Morgan <macromorgan@...mail.com>,
	Yuran Pereira <yuran.pereira@...mail.com>,
	Neil Armstrong <neil.armstrong@...aro.org>,
	Douglas Anderson <dianders@...omium.org>,
	Jitao Shi <jitao.shi@...iatek.com>,
	Cong Yang <yangcong5@...qin.corp-partner.google.com>,
	AngeloGioacchino Del Regno <angelogioacchino.delregno@...labora.com>,
	Daniel Vetter <daniel@...ll.ch>,
	David Airlie <airlied@...il.com>,
	Jessica Zhang <quic_jesszhan@...cinc.com>,
	Maarten Lankhorst <maarten.lankhorst@...ux.intel.com>,
	Matthias Brugger <matthias.bgg@...il.com>,
	Sam Ravnborg <sam@...nborg.org>,
	Thomas Zimmermann <tzimmermann@...e.de>,
	linux-arm-kernel@...ts.infradead.org,
	linux-kernel@...r.kernel.org,
	linux-mediatek@...ts.infradead.org
Subject: [RFT PATCH v2 05/48] drm/panel: boe-tv101wum-nl6: Don't call unprepare+disable at shutdown/remove

It's the responsibility of a correctly written DRM modeset driver to
call drm_atomic_helper_shutdown() at shutdown time and that should be
disabling / unpreparing the panel if needed. Panel drivers shouldn't
be calling these functions themselves.

A recent effort was made to fix as many DRM modeset drivers as
possible [1] [2] [3] and most drivers are fixed now.

A grep through mainline for compatible strings used by this driver
indicates that it is used by Mediatek and Qualcomm boards. Both of
those drivers appear to be correctly calling
drm_atomic_helper_shutdown() so we can remove the calls.

[1] https://lore.kernel.org/r/20230901234015.566018-1-dianders@chromium.org
[2] https://lore.kernel.org/r/20230901234202.566951-1-dianders@chromium.org
[3] https://lore.kernel.org/r/20230921192749.1542462-1-dianders@chromium.org

Cc: Jitao Shi <jitao.shi@...iatek.com>
Cc: Cong Yang <yangcong5@...qin.corp-partner.google.com>
Signed-off-by: Douglas Anderson <dianders@...omium.org>
---

Changes in v2:
- Only handle 1 panel per patch.
- Split removal of prepared/enabled from handling of remove/shutdown.

 drivers/gpu/drm/panel/panel-boe-tv101wum-nl6.c | 11 -----------
 1 file changed, 11 deletions(-)

diff --git a/drivers/gpu/drm/panel/panel-boe-tv101wum-nl6.c b/drivers/gpu/drm/panel/panel-boe-tv101wum-nl6.c
index 667e1bb4a58b..77b20e24cac7 100644
--- a/drivers/gpu/drm/panel/panel-boe-tv101wum-nl6.c
+++ b/drivers/gpu/drm/panel/panel-boe-tv101wum-nl6.c
@@ -1910,21 +1910,11 @@ static int boe_panel_probe(struct mipi_dsi_device *dsi)
 	return ret;
 }
 
-static void boe_panel_shutdown(struct mipi_dsi_device *dsi)
-{
-	struct boe_panel *boe = mipi_dsi_get_drvdata(dsi);
-
-	drm_panel_disable(&boe->base);
-	drm_panel_unprepare(&boe->base);
-}
-
 static void boe_panel_remove(struct mipi_dsi_device *dsi)
 {
 	struct boe_panel *boe = mipi_dsi_get_drvdata(dsi);
 	int ret;
 
-	boe_panel_shutdown(dsi);
-
 	ret = mipi_dsi_detach(dsi);
 	if (ret < 0)
 		dev_err(&dsi->dev, "failed to detach from DSI host: %d\n", ret);
@@ -1972,7 +1962,6 @@ static struct mipi_dsi_driver boe_panel_driver = {
 	},
 	.probe = boe_panel_probe,
 	.remove = boe_panel_remove,
-	.shutdown = boe_panel_shutdown,
 };
 module_mipi_dsi_driver(boe_panel_driver);
 
-- 
2.45.0.rc1.225.g2a3ae87e7f-goog