From patchwork Tue Jun 17 07:31:43 2025 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: Richard Leitner X-Patchwork-Id: 897830 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 7253122AE45; Tue, 17 Jun 2025 07:31:43 +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=1750145503; cv=none; b=mjUIAR6MY8nO1vnpMPR5QbiTmHQgOPsT9eMlvJTWBH8o4KJxRV1A/xst8cJlXSypziywkMu7imw7BJ73Rfatg0Chgyzejkg/rAifoQZSSRzsQr8s/GoU5p/xnl9wk/zuf0mr1QNEgB/+8SiTOkhyZlgL60U9rvWkAq7ifjeFpks= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1750145503; c=relaxed/simple; bh=N7cxIQN6Xv0wE74O59AbStDajdQPgGvjHQmafDljbdA=; h=From:Date:Subject:MIME-Version:Content-Type:Message-Id:References: In-Reply-To:To:Cc; b=niJDWPs7wZcpQ1nuJhQaDUI1bvInk8UFSqNMTHUeqWAldgPIL8LcFDOeKDc4ZMfStbv+mDxfEXbNkp74Lz6iu4eC1Rh3TYOLkI5vvEvCbx7X1g7Kjby4GL4CjrTGJyEXP/t5DMNKUKWYAoEoTTbZ6AR5pK9QR0qW1iTwLK5t7I4= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linux.dev header.i=@linux.dev header.b=vmCdZZjj; 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="vmCdZZjj" Received: by smtp.kernel.org (Postfix) with ESMTPS id 3EAB7C4CEFD; Tue, 17 Jun 2025 07:31:43 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linux.dev; s=korg; t=1750145503; bh=N7cxIQN6Xv0wE74O59AbStDajdQPgGvjHQmafDljbdA=; h=From:Date:Subject:References:In-Reply-To:To:Cc:From; b=vmCdZZjjdAzVlYw533oEp5gac8Ump7xyp7z3f9MKg0ZhOZaavqzGcFwQTj265M47L 43sRFUtjpIf1qVQZGx1mYJf5QKrDxJq2jhcsVR+nROhoE2umufCWOq2y0eZklU1tbv PZXd91H+q9/2oKmxwp/Yijoq3onr6F/O7voT2JTQ= 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 36663C7115D; Tue, 17 Jun 2025 07:31:43 +0000 (UTC) From: Richard Leitner Date: Tue, 17 Jun 2025 09:31:43 +0200 Subject: [PATCH v5 09/10] media: i2c: ov9282: implement try_ctrl for strobe_duration Precedence: bulk X-Mailing-List: linux-media@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Message-Id: <20250617-ov9282-flash-strobe-v5-9-9762da74d065@linux.dev> References: <20250617-ov9282-flash-strobe-v5-0-9762da74d065@linux.dev> In-Reply-To: <20250617-ov9282-flash-strobe-v5-0-9762da74d065@linux.dev> To: Sakari Ailus , Dave Stevenson , Mauro Carvalho Chehab , Lee Jones , Pavel Machek , Laurent Pinchart Cc: Hans Verkuil , linux-media@vger.kernel.org, linux-kernel@vger.kernel.org, linux-leds@vger.kernel.org, Richard Leitner X-Mailer: b4 0.14.2 X-Developer-Signature: v=1; a=ed25519-sha256; t=1750145501; l=3551; i=richard.leitner@linux.dev; s=20250225; h=from:subject:message-id; bh=N7cxIQN6Xv0wE74O59AbStDajdQPgGvjHQmafDljbdA=; b=fdl3inKMgvhpPI2PHcHHcZ8fsLbLgLfEVPSeMsJSf3g4eiVUNuxskBMPTvq2B/NeOcFvLBRj3 hLw+H2YEYrkCHiyK6zg/wYqY7Q9eNfw7rwtdb7yt7vFQ2lcX10EObt7 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 As the granularity of the hardware supported values is lower than the control value, implement a try_ctrl() function for V4L2_CID_FLASH_DURATION. This function calculates the nearest possible µs strobe duration for the given value and returns it back to the caller. Signed-off-by: Richard Leitner --- drivers/media/i2c/ov9282.c | 54 ++++++++++++++++++++++++++++++++++++++++++++-- 1 file changed, 52 insertions(+), 2 deletions(-) diff --git a/drivers/media/i2c/ov9282.c b/drivers/media/i2c/ov9282.c index 2d77b9108bcd2499a40418919e260e7d53a9a64e..1f4bca29cd793e99c473aff9c8b7e200e3d598bc 100644 --- a/drivers/media/i2c/ov9282.c +++ b/drivers/media/i2c/ov9282.c @@ -128,6 +128,8 @@ #define OV9282_REG_MIN 0x00 #define OV9282_REG_MAX 0xfffff +#define OV9282_STROBE_SPAN_FACTOR 192 + static const char * const ov9282_supply_names[] = { "avdd", /* Analog power */ "dovdd", /* Digital I/O power */ @@ -691,7 +693,7 @@ static int ov9282_set_ctrl_flash_led_mode(struct ov9282 *ov9282, int mode) current_val); } -static int ov9282_set_ctrl_flash_duration(struct ov9282 *ov9282, u32 value) +static u32 ov9282_us_to_flash_duration(struct ov9282 *ov9282, u32 value) { /* * Calculate "strobe_frame_span" increments from a given value (µs). @@ -702,7 +704,27 @@ static int ov9282_set_ctrl_flash_duration(struct ov9282 *ov9282, u32 value) * The formula below is interpolated from different modes/framerates * and should work quite well for most settings. */ - u32 val = value * 192 / (ov9282->cur_mode->width + ov9282->hblank_ctrl->val); + u32 frame_width = ov9282->cur_mode->width + ov9282->hblank_ctrl->val; + + return value * OV9282_STROBE_SPAN_FACTOR / frame_width; +} + +static u32 ov9282_flash_duration_to_us(struct ov9282 *ov9282, u32 value) +{ + /* + * As the calculation in ov9282_us_to_flash_duration uses an integer + * divison calculate in ns here to get more precision. Then check if + * we need to compensate that divison by incrementing the µs result. + */ + u32 frame_width = ov9282->cur_mode->width + ov9282->hblank_ctrl->val; + u64 ns = value * 1000 * frame_width / OV9282_STROBE_SPAN_FACTOR; + + return DIV_ROUND_UP(ns, 1000); +} + +static int ov9282_set_ctrl_flash_duration(struct ov9282 *ov9282, u32 value) +{ + u32 val = ov9282_us_to_flash_duration(ov9282, value); ov9282_write_reg(ov9282, OV9282_REG_FLASH_DURATION, 1, (val >> 24) & 0xff); ov9282_write_reg(ov9282, OV9282_REG_FLASH_DURATION + 1, 1, (val >> 16) & 0xff); @@ -792,9 +814,37 @@ static int ov9282_set_ctrl(struct v4l2_ctrl *ctrl) return ret; } +static int ov9282_try_ctrl(struct v4l2_ctrl *ctrl) +{ + struct ov9282 *ov9282 = + container_of(ctrl->handler, struct ov9282, ctrl_handler); + + if (ctrl->id == V4L2_CID_FLASH_DURATION) { + u32 fd = ov9282_us_to_flash_duration(ov9282, ctrl->val); + u32 us = ctrl->val; + + /* get nearest strobe_duration value */ + u32 us0 = ov9282_flash_duration_to_us(ov9282, fd); + u32 us1 = ov9282_flash_duration_to_us(ov9282, (fd + 1)); + + if (abs(us1 - us) < abs(us - us0)) + ctrl->val = us1; + else + ctrl->val = us0; + + if (us != ctrl->val) { + dev_dbg(ov9282->dev, "using next valid strobe_duration %u instead of %u\n", + ctrl->val, us); + } + } + + return 0; +} + /* V4l2 subdevice control ops*/ static const struct v4l2_ctrl_ops ov9282_ctrl_ops = { .s_ctrl = ov9282_set_ctrl, + .try_ctrl = ov9282_try_ctrl, }; /**