From mboxrd@z Thu Jan 1 00:00:00 1970 Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.remote-ip=100.103.45.18 ARC-Seal: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; cv=none; t=1792724776; b=NjZDoxfjP6so8gNvn061jEYsp4GhqXmugD4tetKPd6Nff7RV+S7xnY+Q7L6nOtU5yIvg 4NU0C/cL2r2+KUacv66bQ4ki4fn3x5IysQjD3xOPPO3fnhr/hpcQVRhbaQ1Sq33Tbzow5 ZJ/PKIpys11G+wpJ1xfYoq8ZOI6v/BocJAbtK1/Jz9sSnvQvQEiSujDXFTLb8mJJYePwL RHYll9flikDGXiVQgVUz17vfD7RhsNhT6bcbnzHFUAJk20dAaIor7yZt0Du+YkHBNElZS mjapGeRhR9NgYAtVSzcYxKfKQ/omz8nAvdQxX6JeTMhn3KmmGrvxb8BHQB4boJWeB8w== ARC-Message-Signature: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; c=relaxed/relaxed; t=1792724776; h=Received:DKIM-Signature:Date:From:To:Cc:Subject:Message-ID: In-Reply-To:References:X-Mailer:MIME-Version:Content-Type: Content-Transfer-Encoding; bh=frwXj1z8hv8l/RpQIFEREFwbvpkIu3oS45o4hbxpnuk=; b=4w6DPKxp8AlFsBNCNtPsTnh57t100zyEW991ml+tdoV5zhOBqXKgcUimgGd5tEkDCGtq JEGuf9uhpAhXS2KYfgHq6YzYJDojcraIqQeN1ipi8FUqRrc2SUxMP+scS7vRaM50ur23I YSTsPlA5T1uctgWZvuMwQStES8zmfMqebyvMWn87lZRWf6jcX7cV4l3FRYU86nt3KywZT qddeb73YyCkbCjlzVh7InTv5O2RmnmrPFPjax5yFmTzo36QrkoXyjtU998+V1H8bo7w1L yvuQUYS2GwYT1BrhIl4K3cjxTbSiUatK5rHICHsy0Yt3v4HytSeawHSP6cb7fKcTQHA== ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass header.d=kernel.org header.i=@kernel.org header.a=rsa-sha256 header.s=k20260515 header.b=Q9cBoyuM; arc=none smtp.remote-ip=100.103.45.18 Received: from smtp.kernel.org (quasi.space.kernel.org [100.103.45.18]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (prime256v1)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 859F2606A319; Fri, 23 Oct 2026 03:06:16 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key, unprotected) header.d=kernel.org header.i=@kernel.org header.a=rsa-sha256 header.s=k20260515 header.b=Q9cBoyuM Received: by smtp.kernel.org (Postfix) with ESMTPSA id CD64E1F01825; Fri, 23 Oct 2026 03:06:13 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1792724776; bh=frwXj1z8hv8l/RpQIFEREFwbvpkIu3oS45o4hbxpnuk=; h=Date:From:To:Cc:Subject:In-Reply-To:References; b=Q9cBoyuMF/TmV/iMnSwiD1MEVhEQxn/l8qxVjf+aL66LinbL59PDvpvvYDasJ94UJ /dVFxE6zXdW08H5TbpZN+xzn44R99XGh6RWQwYYh4q8XwcVeGCRQ4tNNqwszjk/2LW snjEuZ/qCihF12VEzTKPgQYDuHkgC1sq1Q4r9LcxyGJvPBBEfEDOx4opYklBLqD7Tg YEqtsQPr6QAHZilBUUJtLVxKIjX7JC02rffjmfB0iMSwiULU01ROHYAYDOxSJ87p2D A28/h3Kmezyc+HJLLeLOMMzR4HASw6Q1LnFa7zm/KDWQKAzeGAxg8kL5VdwaEDvwB7 VxMkAVNF4MuzQ== Date: Fri, 23 Oct 2026 04:06:07 +0100 From: Jonathan Cameron To: Victor Chernyakin Cc: David Lechner , Nuno =?UTF-8?B?U8Oh?= , Andy Shevchenko , linux-iio@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH 1/3] iio: add IIO_VAL_DECIMAL64_{ATTO,ZEPTO,YOCTO} formats Message-ID: <20261023040607.400f8420@jic23-hlaptop> In-Reply-To: References: X-Mailer: Claws Mail 4.4.0 (GTK 3.24.52; x86_64-pc-linux-gnu) X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Post: List-Help: List-Subscribe: List-Unsubscribe: List-Owner: Precedence: list MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit On Thu, 22 Oct 2026 18:40:30 -0500 Victor Chernyakin wrote: > The highest-precision format IIO has right now is IIO_VAL_DECIMAL64_FEMTO, > which gives 15 decimal digits of precision after the decimal point. This > is not enough for the upcoming TI FDC1004 driver, which needs 22 digits > of precision to exactly express its scale value. This patch adds higher- > precision formats, up to IIO_VAL_DECIMAL64_YOCTO (24 digits of precision). > > Signed-off-by: Victor Chernyakin Some discussion of whether these are perhaps overkill in the driver patch given device precision doesn't seem to be nearly that good. > --- > drivers/iio/industrialio-core.c | 6 ++++++ > include/linux/iio/types.h | 3 +++ > 2 files changed, 9 insertions(+) > > diff --git a/drivers/iio/industrialio-core.c b/drivers/iio/industrialio-core.c > index 767a7794624a..008387efe96b 100644 > --- a/drivers/iio/industrialio-core.c > +++ b/drivers/iio/industrialio-core.c > @@ -716,6 +716,9 @@ static ssize_t __iio_format_value(char *buf, size_t offset, unsigned int type, > case IIO_VAL_DECIMAL64_NANO: > case IIO_VAL_DECIMAL64_PICO: > case IIO_VAL_DECIMAL64_FEMTO: Seems we failed to update the test in drivers/iio/tests/iio-test-format.c for FEMTO. Please add that and a similar test for your new units. > + case IIO_VAL_DECIMAL64_ATTO: > + case IIO_VAL_DECIMAL64_ZEPTO: > + case IIO_VAL_DECIMAL64_YOCTO: > { > int scale = type - IIO_VAL_DECIMAL64_BASE; > s64 frac; > @@ -1034,6 +1037,9 @@ static ssize_t iio_write_channel_info(struct device *dev, > case IIO_VAL_DECIMAL64_NANO: > case IIO_VAL_DECIMAL64_PICO: > case IIO_VAL_DECIMAL64_FEMTO: > + case IIO_VAL_DECIMAL64_ATTO: > + case IIO_VAL_DECIMAL64_ZEPTO: > + case IIO_VAL_DECIMAL64_YOCTO: > dec_scale = type - IIO_VAL_DECIMAL64_BASE; > fallthrough; > case IIO_VAL_INT_64: > diff --git a/include/linux/iio/types.h b/include/linux/iio/types.h > index d8944c9e5e90..2ef9b2a8b119 100644 > --- a/include/linux/iio/types.h > +++ b/include/linux/iio/types.h > @@ -43,6 +43,9 @@ enum iio_event_info { > #define IIO_VAL_DECIMAL64_NANO (IIO_VAL_DECIMAL64_BASE + 9) > #define IIO_VAL_DECIMAL64_PICO (IIO_VAL_DECIMAL64_BASE + 12) > #define IIO_VAL_DECIMAL64_FEMTO (IIO_VAL_DECIMAL64_BASE + 15) > +#define IIO_VAL_DECIMAL64_ATTO (IIO_VAL_DECIMAL64_BASE + 18) > +#define IIO_VAL_DECIMAL64_ZEPTO (IIO_VAL_DECIMAL64_BASE + 21) > +#define IIO_VAL_DECIMAL64_YOCTO (IIO_VAL_DECIMAL64_BASE + 24) > > static inline s64 iio_val_s64_compose(s32 val0, s32 val1) > {