From patchwork Wed Aug 17 10:56:42 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Artur Rojek X-Patchwork-Id: 597996 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 0ECBAC2BB41 for ; Wed, 17 Aug 2022 10:57:29 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S239089AbiHQK51 (ORCPT ); Wed, 17 Aug 2022 06:57:27 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:52900 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S239077AbiHQK5Y (ORCPT ); Wed, 17 Aug 2022 06:57:24 -0400 Received: from relay12.mail.gandi.net (relay12.mail.gandi.net [217.70.178.232]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 90E1773908; Wed, 17 Aug 2022 03:57:23 -0700 (PDT) Received: (Authenticated sender: contact@artur-rojek.eu) by mail.gandi.net (Postfix) with ESMTPSA id AC28820000E; Wed, 17 Aug 2022 10:57:20 +0000 (UTC) From: Artur Rojek To: Paul Cercueil , Jonathan Cameron , Dmitry Torokhov , Chris Morgan Cc: linux-mips@vger.kernel.org, linux-iio@vger.kernel.org, linux-kernel@vger.kernel.org, linux-input@vger.kernel.org, Artur Rojek Subject: [PATCH 3/4] iio: add helper function for reading channel offset in buffer Date: Wed, 17 Aug 2022 12:56:42 +0200 Message-Id: <20220817105643.95710-4-contact@artur-rojek.eu> X-Mailer: git-send-email 2.37.2 In-Reply-To: <20220817105643.95710-1-contact@artur-rojek.eu> References: <20220817105643.95710-1-contact@artur-rojek.eu> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-input@vger.kernel.org This is useful for consumers that wish to parse raw buffer data. Tested-by: Paul Cercueil Signed-off-by: Artur Rojek --- drivers/iio/industrialio-buffer.c | 28 ++++++++++++++++++++++++++++ include/linux/iio/buffer.h | 4 ++++ 2 files changed, 32 insertions(+) diff --git a/drivers/iio/industrialio-buffer.c b/drivers/iio/industrialio-buffer.c index 228598b82a2f..cf23736610d9 100644 --- a/drivers/iio/industrialio-buffer.c +++ b/drivers/iio/industrialio-buffer.c @@ -691,6 +691,34 @@ static unsigned int iio_storage_bytes_for_si(struct iio_dev *indio_dev, return bytes; } +int iio_find_channel_offset_in_buffer(struct iio_dev *indio_dev, + const struct iio_chan_spec *chan, + struct iio_buffer *buffer) +{ + int length, offset = 0; + unsigned int si; + + if (chan->scan_index < 0 || + !test_bit(chan->scan_index, buffer->scan_mask)) { + return -EINVAL; + } + + for (si = 0; si < chan->scan_index; ++si) { + if (!test_bit(si, buffer->scan_mask)) + continue; + + length = iio_storage_bytes_for_si(indio_dev, si); + + /* Account for channel alignment. */ + if (offset % length) + offset += length - (offset % length); + offset += length; + } + + return offset; +} +EXPORT_SYMBOL_GPL(iio_find_channel_offset_in_buffer); + static unsigned int iio_storage_bytes_for_timestamp(struct iio_dev *indio_dev) { struct iio_dev_opaque *iio_dev_opaque = to_iio_dev_opaque(indio_dev); diff --git a/include/linux/iio/buffer.h b/include/linux/iio/buffer.h index 418b1307d3f2..b1db74772e77 100644 --- a/include/linux/iio/buffer.h +++ b/include/linux/iio/buffer.h @@ -16,6 +16,10 @@ enum iio_buffer_direction { IIO_BUFFER_DIRECTION_OUT, }; +int iio_find_channel_offset_in_buffer(struct iio_dev *indio_dev, + const struct iio_chan_spec *chan, + struct iio_buffer *buffer); + int iio_push_to_buffers(struct iio_dev *indio_dev, const void *data); int iio_pop_from_buffer(struct iio_buffer *buffer, void *data);