From patchwork Mon Dec 11 10:18:33 2017 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: Arnaud POULIQUEN X-Patchwork-Id: 10104537 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 87E1C602A7 for ; Mon, 11 Dec 2017 10:19:04 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 6C50629467 for ; Mon, 11 Dec 2017 10:19:04 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 601E82952B; Mon, 11 Dec 2017 10:19:04 +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=-1.9 required=2.0 tests=BAYES_00, RCVD_IN_DNSWL_NONE autolearn=ham version=3.3.1 Received: from alsa0.perex.cz (alsa0.perex.cz [77.48.224.243]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 58AF529467 for ; Mon, 11 Dec 2017 10:19:02 +0000 (UTC) Received: from alsa0.perex.cz (localhost [127.0.0.1]) by alsa0.perex.cz (Postfix) with ESMTP id 8D520266BEF; Mon, 11 Dec 2017 11:19:00 +0100 (CET) X-Original-To: alsa-devel@alsa-project.org Delivered-To: alsa-devel@alsa-project.org Received: by alsa0.perex.cz (Postfix, from userid 1000) id 2091E266BEF; Mon, 11 Dec 2017 11:18:59 +0100 (CET) Received: from mx07-00178001.pphosted.com (mx07-00178001.pphosted.com [62.209.51.94]) by alsa0.perex.cz (Postfix) with ESMTP id 7CB96266A74 for ; Mon, 11 Dec 2017 11:18:55 +0100 (CET) Received: from pps.filterd (m0046668.ppops.net [127.0.0.1]) by mx07-.pphosted.com (8.16.0.21/8.16.0.21) with SMTP id vBBAENhG021060; Mon, 11 Dec 2017 11:18:55 +0100 Received: from beta.dmz-eu.st.com (beta.dmz-eu.st.com [164.129.1.35]) by mx07-00178001.pphosted.com with ESMTP id 2er660s34p-1 (version=TLSv1 cipher=ECDHE-RSA-AES256-SHA bits=256 verify=NOT); Mon, 11 Dec 2017 11:18:55 +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 4BA1B4A; Mon, 11 Dec 2017 10:18:54 +0000 (GMT) Received: from Webmail-eu.st.com (Safex1hubcas24.st.com [10.75.90.94]) by zeta.dmz-eu.st.com (STMicroelectronics) with ESMTP id 14D852723; Mon, 11 Dec 2017 10:18:54 +0000 (GMT) Received: from SAFEX1HUBCAS22.st.com (10.75.90.92) by Safex1hubcas24.st.com (10.75.90.94) with Microsoft SMTP Server (TLS) id 14.3.352.0; Mon, 11 Dec 2017 11:18:53 +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; Mon, 11 Dec 2017 11:18:53 +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 Date: Mon, 11 Dec 2017 11:18:33 +0100 Message-ID: <1512987524-2901-3-git-send-email-arnaud.pouliquen@st.com> X-Mailer: git-send-email 2.7.4 In-Reply-To: <1512987524-2901-1-git-send-email-arnaud.pouliquen@st.com> References: <1512987524-2901-1-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=2017-12-11_04:, , signatures=0 Cc: devicetree@vger.kernel.org, alsa-devel@alsa-project.org, Alexandre Torgue , linux-iio@vger.kernel.org, arnaud.pouliquen@st.com, Maxime Coquelin , linux-arm-kernel@lists.infradead.org Subject: [alsa-devel] [PATCH v8 02/13] docs: driver-api: add iio hw consumer section X-BeenThere: alsa-devel@alsa-project.org X-Mailman-Version: 2.1.14 Precedence: list List-Id: "Alsa-devel mailing list for ALSA developers - http://www.alsa-project.org" List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: alsa-devel-bounces@alsa-project.org Sender: alsa-devel-bounces@alsa-project.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 Reviewed-by: Jonathan Cameron --- 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