From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 503EE32D425; Tue, 4 Nov 2025 14:31:10 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1762266670; cv=none; b=VsGs0QTZTTZs9nSSnwfKRZWndUaitCUPJEEjViWNbnTfvDvzGNA/UaHhnuoG8w/r1cHouRQziFKM49kHrQnuc7gFu1KS7k6336JPii35VY4KxZ5uGnFganeWQk5ajFKDP3SgpC2VElsHKfvnoQJbuErfnFk/bxrVsJQorMU2Uro= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1762266670; c=relaxed/simple; bh=yRfk/k98fKVjF+oHG+UiWlyx+HP+Q2RBdionlRvUcH8=; h=From:Date:Subject:MIME-Version:Content-Type:Message-Id:References: In-Reply-To:To:Cc; b=oRGgZzcgjpIDrHNcf7hczsS6H7ocyuxNXjAjf6haUDbxbI1BQBiH2EhpsQvTNhsCHRf/LF6J7E1+ElJlIh+WbfByaUiryLqTYGyBXTKMlROl9eJfigGpyqxspDDGWmRHH238jUCbb1e0bzEfy3sFe6vfc4FT0muq+5sFwAT73bs= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linux.dev header.i=@linux.dev header.b=SniPzikz; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linux.dev header.i=@linux.dev header.b="SniPzikz" Received: by smtp.kernel.org (Postfix) with ESMTPS id CE9E7C19422; Tue, 4 Nov 2025 14:31:09 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linux.dev; s=korg; t=1762266669; bh=yRfk/k98fKVjF+oHG+UiWlyx+HP+Q2RBdionlRvUcH8=; h=From:Date:Subject:References:In-Reply-To:To:Cc:From; b=SniPzikzToANHY29mEWPVJ6f4XZ3SAbtXqChDp8XQmeYnCnc+KtLQGqq9SnpN4Ag9 pvy2uEyrkJbtz93W/hAGHvyOlDQHEn8zqtFg6+GdEcL8OrLq9JX7I3jGm2jRpmWwVb vfN6UPsMTUdYV+ewGTolAvCrbkfmK9wfn7X18Arw= Received: from aws-us-west-2-korg-lkml-1.web.codeaurora.org (localhost.localdomain [127.0.0.1]) by smtp.lore.kernel.org (Postfix) with ESMTP id C2D31CCFA0C; Tue, 4 Nov 2025 14:31:09 +0000 (UTC) From: Richard Leitner Date: Tue, 04 Nov 2025 15:30:54 +0100 Subject: [PATCH v8 3/8] Documentation: uAPI: media: add V4L2_CID_FLASH_{DURATION,STROBE_OE} Precedence: bulk X-Mailing-List: linux-leds@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 8bit Message-Id: <20251104-ov9282-flash-strobe-v8-3-b91dfef1c65a@linux.dev> References: <20251104-ov9282-flash-strobe-v8-0-b91dfef1c65a@linux.dev> In-Reply-To: <20251104-ov9282-flash-strobe-v8-0-b91dfef1c65a@linux.dev> To: Sakari Ailus , Dave Stevenson , Mauro Carvalho Chehab , Lee Jones , Pavel Machek , Laurent Pinchart Cc: linux-media@vger.kernel.org, linux-kernel@vger.kernel.org, linux-leds@vger.kernel.org, Richard Leitner , Hans Verkuil X-Mailer: b4 0.15-dev-509f5 X-Developer-Signature: v=1; a=ed25519-sha256; t=1762266668; l=3445; i=richard.leitner@linux.dev; s=20250225; h=from:subject:message-id; bh=yRfk/k98fKVjF+oHG+UiWlyx+HP+Q2RBdionlRvUcH8=; b=GJcS1zOTAfUQDNL8sTQ05a762z0wJSCOEo3EKCVw1+2AXMurRIkXsoHISjb6lRztmlRpo+gWL dQXNWXXwbJqADPLodjoheroalLedw/i35YenXbOKENZdwSSPJhjqKao X-Developer-Key: i=richard.leitner@linux.dev; a=ed25519; pk=8hZNyyyQFqZ5ruVJsSGBSPIrmJpfDm5HwHU4QVOP1Pk= X-Endpoint-Received: by B4 Relay for richard.leitner@linux.dev/20250225 with auth_id=350 Add the new strobe duration and hardware strobe output enable to v4l uAPI documentation. Additionally add labels for cross-referencing v4l controls. Signed-off-by: Richard Leitner --- .../userspace-api/media/v4l/ext-ctrls-flash.rst | 42 ++++++++++++++++++++++ 1 file changed, 42 insertions(+) diff --git a/Documentation/userspace-api/media/v4l/ext-ctrls-flash.rst b/Documentation/userspace-api/media/v4l/ext-ctrls-flash.rst index d22c5efb806a1..7cf0d33e79ff0 100644 --- a/Documentation/userspace-api/media/v4l/ext-ctrls-flash.rst +++ b/Documentation/userspace-api/media/v4l/ext-ctrls-flash.rst @@ -57,6 +57,8 @@ Flash Control IDs ``V4L2_CID_FLASH_CLASS (class)`` The FLASH class descriptor. +.. _v4l2-cid-flash-led-mode: + ``V4L2_CID_FLASH_LED_MODE (menu)`` Defines the mode of the flash LED, the high-power white LED attached to the flash controller. Setting this control may not be possible in @@ -80,6 +82,8 @@ Flash Control IDs +.. _v4l2-cid-flash-strobe-source: + ``V4L2_CID_FLASH_STROBE_SOURCE (menu)`` Defines the source of the flash LED strobe. @@ -96,6 +100,12 @@ Flash Control IDs - The flash strobe is triggered by an external source. Typically this is a sensor, which makes it possible to synchronise the flash strobe start to exposure start. + This method of controlling flash LED strobe has two additional + prerequisites: the strobe source's :ref:`strobe output + ` must be enabled (if available) + and the flash controller's :ref:`flash LED mode + ` must be set to + ``V4L2_FLASH_LED_MODE_FLASH``. @@ -186,3 +196,35 @@ Flash Control IDs charged before strobing. LED flashes often require a cooldown period after strobe during which another strobe will not be possible. This is a read-only control. + +.. _v4l2-cid-flash-duration: + +``V4L2_CID_FLASH_DURATION (integer)`` + Duration of the flash strobe pulse generated by the strobe source, when + using external strobe. This control shall be implemented by the device + generating the hardware flash strobe signal, typically a camera sensor, + connected to a flash controller. + + The flash controllers :ref:`strobe source ` + must be configured to ``V4L2_FLASH_STROBE_SOURCE_EXTERNAL`` for this + mode of operation. For more details please also take a look at the + documentation there. + + The unit should be microseconds (µs) if possible. + +.. _v4l2-cid-flash-strobe-oe: + +``V4L2_CID_FLASH_STROBE_OE (boolean)`` + Enables the output of a hardware strobe signal from the strobe source, + when using external strobe. This control shall be implemented by the device + generating the hardware flash strobe signal, typically a camera sensor, + connected to a flash controller. + + Provided the signal generating device driver supports it, the length of the + strobe signal can be configured by adjusting its + :ref:`flash duration `. + + The flash controllers :ref:`strobe source ` + must be configured to ``V4L2_FLASH_STROBE_SOURCE_EXTERNAL`` for this + mode of operation. For more details please also take a look at the + documentation there. -- 2.47.3