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bh=mKxj3pSD0UwzMwdxWit8kdJvq0oc5hRaBZzxFkTM46k=; b=Jt11DHRqH/hXBBUEMf6EkKmyU63Y9/C8UFL/hQXT+cT/sBvJcPNHnTdb21tQMKpXIIaS8n Tjy72dAH3yPLxX3dqKeROQm5keBVXaUjd58v3UNMxIspmoEGRvwT69peKmMTNn0e6daa3V al+b+2v6RA3XNUzYrjh+Ey+kJLdoxAbWb8xNz01kb1g5TW7VMLqikmvXvt4uv+Fj1KkHc1 DzrZkzZzMjh0JRsawywnNJabEBCijVEZfARH8y0/h/S76bj5yLmPNv8qg/6yDyiExoH/JF SR5yL1Mt/orv91qMJq3j0p//MLNZTzIkWXA7UVywXc+HYC491xHAPngeJJyqBA== Date: Fri, 7 Feb 2025 09:53:18 +0100 From: Luca Ceresoli To: Dmitry Baryshkov Cc: Simona Vetter , Inki Dae , Jagan Teki , Marek Szyprowski , Catalin Marinas , Will Deacon , Shawn Guo , Sascha Hauer , Pengutronix Kernel Team , Fabio Estevam , Daniel Thompson , Andrzej Hajda , Jonathan Corbet , Sam Ravnborg , Boris Brezillon , Nicolas Ferre , Alexandre Belloni , Claudiu Beznea , Jessica Zhang , Paul Kocialkowski , Maxime Ripard , Neil Armstrong , Robert Foss , Laurent Pinchart , Jonas Karlman , Jernej Skrabec , Maarten Lankhorst , Thomas Zimmermann , David Airlie , =?UTF-8?Q?Herv?= =?UTF-8?Q?=C3=A9?= Codina , Thomas Petazzoni , linux-kernel@vger.kernel.org, dri-devel@lists.freedesktop.org, linux-doc@vger.kernel.org, linux-arm-kernel@lists.infradead.org, Paul Kocialkowski Subject: Re: [PATCH v6 13/26] drm/encoder: add drm_encoder_cleanup_from() Message-ID: <20250207095318.2fc8d54e@booty> In-Reply-To: References: <20250206-hotplug-drm-bridge-v6-0-9d6f2c9c3058@bootlin.com> <20250206-hotplug-drm-bridge-v6-13-9d6f2c9c3058@bootlin.com> Organization: Bootlin X-Mailer: Claws Mail 4.0.0 (GTK+ 3.24.33; x86_64-pc-linux-gnu) Precedence: bulk X-Mailing-List: linux-doc@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit X-GND-State: clean X-GND-Score: -100 X-GND-Cause: gggruggvucftvghtrhhoucdtuddrgeefvddrtddtgddvkeekgecutefuodetggdotefrodftvfcurfhrohhfihhlvgemucfitefpfffkpdcuggftfghnshhusghstghrihgsvgenuceurghilhhouhhtmecufedtudenucesvcftvggtihhpihgvnhhtshculddquddttddmnecujfgurhepfffhvfevuffkjghfohfogggtgfesthejredtredtvdenucfhrhhomhepnfhutggrucevvghrvghsohhlihcuoehluhgtrgdrtggvrhgvshholhhisegsohhothhlihhnrdgtohhmqeenucggtffrrghtthgvrhhnpeeglefffefghefhtddvfeeufeeiveekgffgleekieduteekkeetvdehudekgfdvvdenucffohhmrghinhepsghoohhtlhhinhdrtghomhenucfkphepvdgrtddvmeeijedtmedvtddvtdemvggrtddumegtvgejvgemiegtgegvmeeitggtjeemleekgeejnecuvehluhhsthgvrhfuihiivgeptdenucfrrghrrghmpehinhgvthepvdgrtddvmeeijedtmedvtddvtdemvggrtddumegtvgejvgemiegtgegvmeeitggtjeemleekgeejpdhhvghlohepsghoohhthidpmhgrihhlfhhrohhmpehluhgtrgdrtggvrhgvshholhhisegsohhothhlihhnrdgtohhmpdhnsggprhgtphhtthhopeefjedprhgtphhtthhopegumhhithhrhidrsggrrhihshhhkhhovheslhhinhgrrhhordhorhhgpdhrtghpthhtohepshhimhhonhgrsehffhiflhhlrdgthhdprhgtphhtthhopehinhhkihdruggrvgesshgrmhhsuhhnghdrt ghomhdprhgtphhtthhopehjrghgrghnsegrmhgrrhhulhgrshholhhuthhiohhnshdrtghomhdprhgtphhtthhopehmrdhsiiihphhrohifshhkihesshgrmhhsuhhnghdrtghomhdprhgtphhtthhopegtrghtrghlihhnrdhmrghrihhnrghssegrrhhmrdgtohhmpdhrtghpthhtohepfihilhhlsehkvghrnhgvlhdrohhrghdprhgtphhtthhopehshhgrfihnghhuoheskhgvrhhnvghlrdhorhhg X-GND-Sasl: luca.ceresoli@bootlin.com On Fri, 7 Feb 2025 05:03:13 +0200 Dmitry Baryshkov wrote: > On Thu, Feb 06, 2025 at 07:14:28PM +0100, Luca Ceresoli wrote: > > Supporting hardware whose final part of the DRM pipeline can be physically > > removed requires the ability to detach all bridges from a given point to > > the end of the pipeline. > > > > Introduce a variant of drm_encoder_cleanup() for this. > > > > Signed-off-by: Luca Ceresoli > > > > --- > > > > Changes in v6: none > > Changes in v5: none > > Changes in v4: none > > Changes in v3: none > > > > Changed in v2: > > - fix a typo in a comment > > --- > > drivers/gpu/drm/drm_encoder.c | 21 +++++++++++++++++++++ > > include/drm/drm_encoder.h | 1 + > > 2 files changed, 22 insertions(+) > > > > diff --git a/drivers/gpu/drm/drm_encoder.c b/drivers/gpu/drm/drm_encoder.c > > index 8f2bc6a28482229fd0b030a1958f87753ad7885f..472dfbefe2960924a4e83bec425af8c7ef5f5265 100644 > > --- a/drivers/gpu/drm/drm_encoder.c > > +++ b/drivers/gpu/drm/drm_encoder.c > > @@ -207,6 +207,27 @@ void drm_encoder_cleanup(struct drm_encoder *encoder) > > } > > EXPORT_SYMBOL(drm_encoder_cleanup); > > > > +/** > > + * drm_encoder_cleanup_from - remove a given bridge and all the following > > + * @encoder: encoder whole list of bridges shall be pruned > > + * @bridge: first bridge to remove > > + * > > + * Removes from an encoder all the bridges starting with a given bridge > > + * and until the end of the chain. > > + * > > + * This should not be used in "normal" DRM pipelines. It is only useful for > > + * devices whose final part of the DRM chain can be physically removed and > > + * later reconnected (possibly with different hardware). > > + */ > > +void drm_encoder_cleanup_from(struct drm_encoder *encoder, struct drm_bridge *bridge) > > +{ > > + struct drm_bridge *next; > > + > > + list_for_each_entry_safe_from(bridge, next, &encoder->bridge_chain, chain_node) > > + drm_bridge_detach(bridge); > > +} > > +EXPORT_SYMBOL(drm_encoder_cleanup_from); > > Shouldn't drm_encoder_cleanup() also use this function? Sure. I'll do it in v7. Luca -- Luca Ceresoli, Bootlin Embedded Linux and Kernel engineering https://bootlin.com