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 F0C1B1531CB; Sat, 28 Sep 2024 17:25:10 +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=1727544311; cv=none; b=AE1/5u7q0WCqiM+frd8aDD3zHrKiRx1iLxONehhLSpOzACGJERUEf1w+iV6Syh7VQVA2/TaGvHQN/duX92OGhBSr7ce9mDwUBNZfVJyXjeGRaahApZbp71xOOr9DjW89QWM+msJSguMbZ5USd/Yc81J3Eb0Vh8C4dwVM2nVLGs8= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1727544311; c=relaxed/simple; bh=IjPaXoJUOuxQfoMfc1RuNS6iFJFev3/P85f58SkSDfU=; h=Date:From:To:Cc:Subject:Message-ID:In-Reply-To:References: MIME-Version:Content-Type; b=aOStcs9odeBBVOuN+7AKPjcUtlULsuwb2GckN4WrKus4XS+sJxx57e6z5GpSWPBzY1KKXLyXvAWrCHpHUfiDGJ/dOha+zQlAVbitbNjpaWh8lNAa8h4gUHdY4eNtZ6IH0M2fnE1iVTVXjn1Ki2Yv8tOrgivjqLcMItwQMZzxh9A= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=tMpImFzb; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="tMpImFzb" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 9E7DFC4CEC3; Sat, 28 Sep 2024 17:25:02 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1727544310; bh=IjPaXoJUOuxQfoMfc1RuNS6iFJFev3/P85f58SkSDfU=; h=Date:From:To:Cc:Subject:In-Reply-To:References:From; b=tMpImFzbe1/6Ar934ecy2fJYGP8CijrwbhOZBbXYCMBvbvGxDv9I/LfK/NROqQ6Hz dNJH2w/1Fb1nPOuCDdGTbFlbQ30Fljk4io8D1H2VaqEObUZJKBNqQHCPNdAHh2/FN8 4If3GIX0FYf8zc48i7qkWpKH3faaVH9ux6mqTj/E4qYyNPyoKwxLs/5mo50e5d9KRe 2yqUNV0RPOnYw7YIkXHgoaWS1xxPIVWKEzQx65qmAhAITkAmEQ1OeQGN6SKfT1o0rx HUhIHz3FgwdcHRVTSSzcRewE5FBCGXqS386J/jDb2rOqgkTtCcYyxaEtfaUjN2Fgxs 5NmaccmrWMXJA== Date: Sat, 28 Sep 2024 18:24:57 +0100 From: Jonathan Cameron To: Antoniu Miclaus Cc: Lars-Peter Clausen , Michael Hennerich , Rob Herring , Krzysztof Kozlowski , Conor Dooley , Nuno Sa , Olivier Moysan , Uwe =?UTF-8?B?S2xlaW5lLUvDtm5pZw==?= , Andy Shevchenko , David Lechner , Marcelo Schmitt , =?UTF-8?B?Sm/Do28=?= Paulo =?UTF-8?B?R29u?= =?UTF-8?B?w6dhbHZlcw==?= , Dumitru Ceclan , AngeloGioacchino Del Regno , Alisa-Dariana Roman , Marius Cristea , Sergiu Cuciurean , Dragos Bogdan , , , , Subject: Re: [PATCH 2/7] iio: backend: add support for data size set Message-ID: <20240928182457.5919be0d@jic23-huawei> In-Reply-To: <20240923101206.3753-3-antoniu.miclaus@analog.com> References: <20240923101206.3753-1-antoniu.miclaus@analog.com> <20240923101206.3753-3-antoniu.miclaus@analog.com> X-Mailer: Claws Mail 4.3.0 (GTK 3.24.43; x86_64-pc-linux-gnu) Precedence: bulk X-Mailing-List: devicetree@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit On Mon, 23 Sep 2024 13:10:19 +0300 Antoniu Miclaus wrote: > Add backend support for setting the data size used. Say 'why' a device might do this. I assume in general it's because you haven't wired all the pins, but is there a reason it might be dynamic? Jonathan > > Signed-off-by: Antoniu Miclaus > --- > drivers/iio/industrialio-backend.c | 21 +++++++++++++++++++++ > include/linux/iio/backend.h | 3 +++ > 2 files changed, 24 insertions(+) > > diff --git a/drivers/iio/industrialio-backend.c b/drivers/iio/industrialio-backend.c > index 53ab6bc86a50..a6a6bedce7f1 100644 > --- a/drivers/iio/industrialio-backend.c > +++ b/drivers/iio/industrialio-backend.c > @@ -473,6 +473,27 @@ int iio_backend_interface_type_get(struct iio_backend *back, > } > EXPORT_SYMBOL_NS_GPL(iio_backend_interface_type_get, IIO_BACKEND); > > +/** > + * iio_backend_data_size_set - set the data width/size in the data bus. > + * @back: Backend device > + * @size: Size in bits > + * > + * Some frontend devices can dynamically control the word/data size on the > + * interface/data bus. Hence, the backend device needs to be aware of it so > + * data can be correctly transferred. > + * > + * RETURNS: > + * 0 on success, negative error number on failure. > + */ > +ssize_t iio_backend_data_size_set(struct iio_backend *back, ssize_t size) > +{ > + if (!size) > + return -EINVAL; > + > + return iio_backend_op_call(back, data_size_set, size); > +} > +EXPORT_SYMBOL_NS_GPL(iio_backend_data_size_set, IIO_BACKEND); > + > /** > * iio_backend_extend_chan_spec - Extend an IIO channel > * @indio_dev: IIO device > diff --git a/include/linux/iio/backend.h b/include/linux/iio/backend.h > index ba8ad30ac9ba..85b33ed69cc0 100644 > --- a/include/linux/iio/backend.h > +++ b/include/linux/iio/backend.h > @@ -87,6 +87,7 @@ enum iio_backend_interface_type { > * @ext_info_set: Extended info setter. > * @ext_info_get: Extended info getter. > * @interface_type_get: Interface type. > + * @data_size_set: Data size. > **/ > struct iio_backend_ops { > int (*enable)(struct iio_backend *back); > @@ -121,6 +122,7 @@ struct iio_backend_ops { > const struct iio_chan_spec *chan, char *buf); > int (*interface_type_get)(struct iio_backend *back, > enum iio_backend_interface_type *type); > + int (*data_size_set)(struct iio_backend *back, ssize_t size); > }; > > int iio_backend_chan_enable(struct iio_backend *back, unsigned int chan); > @@ -152,6 +154,7 @@ ssize_t iio_backend_ext_info_get(struct iio_dev *indio_dev, uintptr_t private, > > int iio_backend_interface_type_get(struct iio_backend *back, > enum iio_backend_interface_type *type); > +ssize_t iio_backend_data_size_set(struct iio_backend *back, ssize_t size); > int iio_backend_extend_chan_spec(struct iio_dev *indio_dev, > struct iio_backend *back, > struct iio_chan_spec *chan);