From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-pl1-f175.google.com (mail-pl1-f175.google.com [209.85.214.175]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 6A4282ECEAE; Sat, 6 Sep 2025 12:54:02 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.214.175 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1757163243; cv=none; b=SfDTy1T2+BHD26rOoHAwLPeqBQlLVCHMw04QPRo0qoZbVE6aJUkAEne9209wzphJr4A53CfFTIFKQ3JL7H46sZKzNMNyqljHYUKIZUcc1yB53xpxWbtDRt8yYQAfAAR4OZH+korT6T1ZsPIxBhhnHFq52bkXzDfkj/8kV+HmtpE= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1757163243; c=relaxed/simple; bh=bMWnIdPIuLs8f+AwFZer1aNYdwbjKwIKbxoEOyaxKpE=; h=Message-ID:Date:MIME-Version:To:Cc:From:Subject:Content-Type; b=KT/5pmBrmDAg2Nq7bBTGysHVGPW9uD+vLnvdqy4+8fsHvZu40h/Lj8lB0ZEdj7Ga6EOTHDgvRhDweGwgvHHq7CtkLG3wwHn3yNt4jQVbAwLk3jM9D20vo4KN/DYjwiG2+F9OL9mxGAtpwMhmL0c5BsurCtRuuiLWd0cGsnkLbLo= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=kzalloc.com; spf=pass smtp.mailfrom=gmail.com; arc=none smtp.client-ip=209.85.214.175 Authentication-Results: smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=kzalloc.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=gmail.com Received: by mail-pl1-f175.google.com with SMTP id d9443c01a7336-24b132bd90dso5710705ad.0; Sat, 06 Sep 2025 05:54:02 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1757163242; x=1757768042; h=content-transfer-encoding:organization:subject:from:cc:to :content-language:user-agent:mime-version:date:message-id :x-gm-message-state:from:to:cc:subject:date:message-id:reply-to; bh=c0a77094FEb9GuihsWwkaplZsNtpOCd+IdcCOf8V6GQ=; b=fGn3ZZ+eZ74jOBAEOpG3lqjean6B0Z+S4y2/S4Nl3yNiQ+50HcTLxQW7Gun6vx1E00 /OM4+sBhWFBErH29Ew9/LdGkXGr8Gry5cL6lDay1I9P2KEm5k+cZj6RfnL//kgRKHa2a naIjyMduq3nwg/O0sNytsgAi3S9S+rIGO6YXCjbeWQl9PzWTYRKFFFSpQXP5suvZ28ZN kvkMUh0vpJuZ2v1S6M/Q7mu4YP8KH16XtWHFRyUK7Yn3fKb04mTgLIK/qnwkbmZjUdS/ TTOo9osDB8xHCQ8IlWu2encdnZaQeusQmUgKG0PhZQ+VriLMR8SRxhz5j8MDaxLm9npv PTag== X-Forwarded-Encrypted: i=1; AJvYcCUywPt60nUBhtuQfvM4lSBOw+q0BEwF7SIJWpxvBC3fkteVPxZ7X+YDT1Duxuf05XTiKF3zfAKUmp3UWWA=@vger.kernel.org X-Gm-Message-State: AOJu0Yz/Fxmgttbf/4wEOTAeIMx7yzeDHMD+pgjXIxysQxcNdJvvDF4b lwt6pjj98lkfd/rxeVBfHm2+cc9bpc078Zkne8WJkZxuuMrUPcyOY/SD72HHMQ== X-Gm-Gg: ASbGncslEP/ZHLpyfGTtWz+4QFxshWjRhKL33NsaIJ4NpFre5xLoVCh3wqE9riGic5a ZtdDjawUsNRuwWMFT8qeg4PhEbTKGhb+dIM8mwEQF1GuL19uBS+CBw14s91bSOWzhSIhZy3yPFu +szbed9JS2prhbTjFHQdC6vrOkLYboijDra4cNygbO//BPitTc+wLStiXX4zeJGUzdVXE3+Deus 0hPEBCfVoEgYg3pPszHtAUq6GFx8aIBnm/NiUwPTZIHoQYcjz9x04kwUUmzz9BiHOv5JvnCZEDf +3AA4MpMxonA2Gf2lrWYOgnKFdEYknT63oP4kJTL08fUik87FbesDXMKuSaOei1kKpPvjgvRfc/ 47a3XbFETQ0sqCIWyVtt5l+fVaV1dmHMT5yMLyrTFewBI6+qTTsMx8ZJtLj6lTt9iYnRZmRe3cX zQm0pfq7iO3fEWB+DsAegZHncS6VlD X-Google-Smtp-Source: AGHT+IFGwSZz0peeD54EP712jVZpITKjp33SOOjG9lEoVNMZoDPVwbepYGSheS//hzxTlrhv9PHwZQ== X-Received: by 2002:a05:6a20:938c:b0:250:d384:e5aa with SMTP id adf61e73a8af0-2533e47d8e7mr1732567637.1.1757163241494; Sat, 06 Sep 2025 05:54:01 -0700 (PDT) Received: from [192.168.50.136] ([118.32.98.101]) by smtp.gmail.com with ESMTPSA id 41be03b00d2f7-b4e5684da06sm18491830a12.17.2025.09.06.05.53.59 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Sat, 06 Sep 2025 05:54:01 -0700 (PDT) Message-ID: Date: Sat, 6 Sep 2025 21:53:57 +0900 Precedence: bulk X-Mailing-List: linux-media@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Content-Language: en-US To: Mauro Carvalho Chehab Cc: linux-media@vger.kernel.org, linux-kernel@vger.kernel.org From: Yunseong Kim Subject: [Question] __u32 rangehigh in struct v4l2_frequency_band to a higher frequencies value Organization: kzalloc Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Hello Mauro, I have a question regarding the data type used in struct v4l2_frequency_band, Current definition: struct v4l2_frequency_band { ... __u32 rangehigh; ... }; According to the official HackRF One documentation, frequency ranges up to 6 GHz are supported. However, the rangehigh field is currently defined as __u32. This means values above present 4294967294LL cannot be represented: https://elixir.bootlin.com/linux/v6.17-rc4/source/drivers/media/usb/hackrf/hackrf.c#L67 For example, the HackRF hardware itself can go over 6 GHz, even though the officially provided ANT700 antenna only supports up to 1.1 GHz: https://greatscottgadgets.com/ant700/ With a different antenna, it seems feasible to use HackRF at 5.8 GHz related discussion: https://github.com/greatscottgadgets/hackrf/issues/1274 Would it make sense to extend struct v4l2_frequency_band to allow rangehigh values up to at least 6000000000ULL? Or has there already been any discussion about changing this field to a wider type for SDR devices that support higher frequencies? I tried searching the mailing list archives for discussions on v4l2_frequency_band rangehigh but couldn’t find anything relevant: https://www.mail-archive.com/search?a=1&l=linux-media%40vger.kernel.org&haswords=v4l2_frequency_band+rangehigh&x=0&y=0&from=&subject=&datewithin=1d&date=¬words=&o=relevance Examples in drivers: .rangehigh = 4294967294LL, /* max u32, hw goes over 7GHz */ Possible adjustment: struct v4l2_frequency_band { ... __u64 rangehigh; ... }; .rangehigh = 6000000000ULL, /* 1 Hz to 6 GHz */ I’d appreciate your advice on whether extending this field (e.g., to __u64) would be the right direction, or if there are other considerations in the V4L2 framework. Thank you very much for your time. Best regards, Yunseong Kim