From patchwork Tue Nov 28 15:05:46 2017 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: Arnaud POULIQUEN X-Patchwork-Id: 10080525 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork.web.codeaurora.org (Postfix) with ESMTP id 02D7060353 for ; Tue, 28 Nov 2017 15:08:28 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id F3A8C29357 for ; Tue, 28 Nov 2017 15:08:27 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id E81942935E; Tue, 28 Nov 2017 15:08:27 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-6.9 required=2.0 tests=BAYES_00,RCVD_IN_DNSWL_HI autolearn=ham version=3.3.1 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id D720A29357 for ; Tue, 28 Nov 2017 15:08:26 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753749AbdK1PIZ (ORCPT ); Tue, 28 Nov 2017 10:08:25 -0500 Received: from mx08-00178001.pphosted.com ([91.207.212.93]:10733 "EHLO mx07-00178001.pphosted.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1753484AbdK1PIV (ORCPT ); Tue, 28 Nov 2017 10:08:21 -0500 Received: from pps.filterd (m0046660.ppops.net [127.0.0.1]) by mx08-.pphosted.com (8.16.0.21/8.16.0.21) with SMTP id vASF4QSW008006; Tue, 28 Nov 2017 16:06:07 +0100 Received: from beta.dmz-eu.st.com (beta.dmz-eu.st.com [164.129.1.35]) by mx08-00178001.pphosted.com with ESMTP id 2eexh9gaug-1 (version=TLSv1 cipher=ECDHE-RSA-AES256-SHA bits=256 verify=NOT); Tue, 28 Nov 2017 16:06:07 +0100 Received: from zeta.dmz-eu.st.com (zeta.dmz-eu.st.com [164.129.230.9]) by beta.dmz-eu.st.com (STMicroelectronics) with ESMTP id A5F2D34; Tue, 28 Nov 2017 15:06:06 +0000 (GMT) Received: from Webmail-eu.st.com (Safex1hubcas21.st.com [10.75.90.44]) by zeta.dmz-eu.st.com (STMicroelectronics) with ESMTP id 81EC45315; Tue, 28 Nov 2017 15:06:06 +0000 (GMT) Received: from SAFEX1HUBCAS22.st.com (10.75.90.93) by SAFEX1HUBCAS21.st.com (10.75.90.44) with Microsoft SMTP Server (TLS) id 14.3.352.0; Tue, 28 Nov 2017 16:06:06 +0100 Received: from localhost (10.201.23.162) by Webmail-ga.st.com (10.75.90.48) with Microsoft SMTP Server (TLS) id 14.3.352.0; Tue, 28 Nov 2017 16:06:06 +0100 From: Arnaud Pouliquen To: Rob Herring , Mark Rutland , Jonathan Cameron , Hartmut Knaack , Lars-Peter Clausen , Peter Meerwald-Stadler , Jaroslav Kysela , Takashi Iwai , Liam Girdwood , Mark Brown CC: , , , , Maxime Coquelin , Alexandre Torgue , Subject: [PATCH v5 02/13] docs: driver-api: add iio hw consumer section Date: Tue, 28 Nov 2017 16:05:46 +0100 Message-ID: <1511881557-28596-3-git-send-email-arnaud.pouliquen@st.com> X-Mailer: git-send-email 2.7.4 In-Reply-To: <1511881557-28596-1-git-send-email-arnaud.pouliquen@st.com> References: <1511881557-28596-1-git-send-email-arnaud.pouliquen@st.com> MIME-Version: 1.0 X-Originating-IP: [10.201.23.162] X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10432:, , definitions=2017-11-28_10:, , signatures=0 Sender: linux-iio-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-iio@vger.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP This adds a section about the Hardware consumer API of the IIO subsystem to the driver API documentation. Signed-off-by: Arnaud Pouliquen --- V4->V5: Minor formating fixes. Documentation/driver-api/iio/hw-consumer.rst | 51 ++++++++++++++++++++++++++++ Documentation/driver-api/iio/index.rst | 1 + 2 files changed, 52 insertions(+) create mode 100644 Documentation/driver-api/iio/hw-consumer.rst diff --git a/Documentation/driver-api/iio/hw-consumer.rst b/Documentation/driver-api/iio/hw-consumer.rst new file mode 100644 index 0000000..8facce6 --- /dev/null +++ b/Documentation/driver-api/iio/hw-consumer.rst @@ -0,0 +1,51 @@ +=========== +HW consumer +=========== +An IIO device can be directly connected to another device in hardware. in this +case the buffers between IIO provider and IIO consumer are handled by hardware. +The Industrial I/O HW consumer offers a way to bond these IIO devices without +software buffer for data. The implementation can be found under +:file:`drivers/iio/buffer/hw-consumer.c` + + +* struct :c:type:`iio_hw_consumer` — Hardware consumer structure +* :c:func:`iio_hw_consumer_alloc` — Allocate IIO hardware consumer +* :c:func:`iio_hw_consumer_free` — Free IIO hardware consumer +* :c:func:`iio_hw_consumer_enable` — Enable IIO hardware consumer +* :c:func:`iio_hw_consumer_disable` — Disable IIO hardware consumer + + +HW consumer setup +================= + +As standard IIO device the implementation is based on IIO provider/consumer. +A typical IIO HW consumer setup looks like this:: + + static struct iio_hw_consumer *hwc; + + static const struct iio_info adc_info = { + .read_raw = adc_read_raw, + }; + + static int adc_read_raw(struct iio_dev *indio_dev, + struct iio_chan_spec const *chan, int *val, + int *val2, long mask) + { + ret = iio_hw_consumer_enable(hwc); + + /* Acquire data */ + + ret = iio_hw_consumer_disable(hwc); + } + + static int adc_probe(struct platform_device *pdev) + { + hwc = devm_iio_hw_consumer_alloc(&iio->dev); + } + +More details +============ +.. kernel-doc:: include/linux/iio/hw-consumer.h +.. kernel-doc:: drivers/iio/buffer/industrialio-hw-consumer.c + :export: + diff --git a/Documentation/driver-api/iio/index.rst b/Documentation/driver-api/iio/index.rst index e5c3922..7fba341 100644 --- a/Documentation/driver-api/iio/index.rst +++ b/Documentation/driver-api/iio/index.rst @@ -15,3 +15,4 @@ Contents: buffers triggers triggered-buffers + hw-consumer