From patchwork Fri Apr 5 15:00:07 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Nuno Sa X-Patchwork-Id: 13619143 Received: from mx0b-00128a01.pphosted.com (mx0a-00128a01.pphosted.com [148.163.135.77]) (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 5E82E16F27A; Fri, 5 Apr 2024 14:57:16 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=148.163.135.77 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1712329038; cv=none; b=lALvVIUEYyuWHLy/rGHCMYbIK/w47bqkayTs0AVdrcAj9jVG8qcfBvF+1c1rjFZ1q3YxJlUY/6b80SzhwpZhK5etN+gOl7s0VUEcbTUFV9w4mNyuXU9aw9FO1K6DkpCYBK0zuQt7v4l7g7xEVIblVDc0y3pvShHJPPwyuf3jYbM= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1712329038; c=relaxed/simple; bh=xgAmECrFsUTtJCoji/lM3kzwfT9+MC3hA0V2gf7cX68=; h=From:Date:Subject:MIME-Version:Content-Type:Message-ID:References: In-Reply-To:To:CC; b=FPRI2Az79POnmSQCSbc4ANes+8ILUeK5Z7Sg1QMpfsS7OKpqG+VrXCKPI+uJVnnz0d5BLOLCnQP2VjLtspecGr6X/k7h6zrqef8Nd7XcXwk6vO0mcRjv8+0hCIrmPHOZT6BnbaEws3bXSJMJs/bMIRnSLo7IQuYfZFaVIkh/DWI= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=analog.com; spf=pass smtp.mailfrom=analog.com; dkim=pass (2048-bit key) header.d=analog.com header.i=@analog.com header.b=nTMXixRq; arc=none smtp.client-ip=148.163.135.77 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=analog.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=analog.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=analog.com header.i=@analog.com header.b="nTMXixRq" Received: from pps.filterd (m0375855.ppops.net [127.0.0.1]) by mx0b-00128a01.pphosted.com (8.17.1.24/8.17.1.24) with ESMTP id 435EeV2O002582; Fri, 5 Apr 2024 10:56:58 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=analog.com; h= from:date:subject:mime-version:content-type :content-transfer-encoding:message-id:references:in-reply-to:to :cc; s=DKIM; bh=kYL1KZM3x8Q8eUpSr+bjTkFGUBqI96OjKx+ouiwycZA=; b= nTMXixRqZVaacNvILm9XNgOPo6aPh2N3dXJ3G4fu6F/4mZf2/L3QSpjj1PeLTAQD Y7XIbXhSxILxwefotmIcBr7C527g4B4Ti5MQmJ8cCW5c7P9w8GXgDVPIe57vIFPn qscKhVFduQIYgiI8TuFTAVhLsk1jiaPo73gHkPqqPSdWlRQF3n9m17Sz8osQUwFg onGJ0ujZHjAjbiMLr6uuH2+dwFkT3FQmbd6kQYrcZgtPo3nEy5WOVeUjQ/68zxR4 Vdnd25NseY3ZXdTz1VuoYn0WqyhQx5LAbeDGEhZTBIH3JdKu7oWSMQov4ON3zbkC B7xLHRotCRyPpvlzfpZeuw== Received: from nwd2mta3.analog.com ([137.71.173.56]) by mx0b-00128a01.pphosted.com (PPS) with ESMTPS id 3xak96r2k4-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Fri, 05 Apr 2024 10:56:58 -0400 (EDT) Received: from ASHBMBX9.ad.analog.com (ASHBMBX9.ad.analog.com [10.64.17.10]) by nwd2mta3.analog.com (8.14.7/8.14.7) with ESMTP id 435Euul7022821 (version=TLSv1/SSLv3 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=FAIL); Fri, 5 Apr 2024 10:56:56 -0400 Received: from ASHBCASHYB4.ad.analog.com (10.64.17.132) by ASHBMBX9.ad.analog.com (10.64.17.10) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.2.986.14; Fri, 5 Apr 2024 10:56:55 -0400 Received: from ASHBMBX8.ad.analog.com (10.64.17.5) by ASHBCASHYB4.ad.analog.com (10.64.17.132) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.2.986.14; Fri, 5 Apr 2024 10:56:55 -0400 Received: from zeus.spd.analog.com (10.66.68.11) by ashbmbx8.ad.analog.com (10.64.17.5) with Microsoft SMTP Server id 15.2.986.14 via Frontend Transport; Fri, 5 Apr 2024 10:56:55 -0400 Received: from [127.0.0.1] ([10.44.3.56]) by zeus.spd.analog.com (8.15.1/8.15.1) with ESMTP id 435EuSI7019011; Fri, 5 Apr 2024 10:56:50 -0400 From: Nuno Sa Date: Fri, 5 Apr 2024 17:00:07 +0200 Subject: [PATCH v2 09/11] iio: backend: add new functionality Precedence: bulk X-Mailing-List: linux-iio@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Message-ID: <20240405-iio-backend-axi-dac-v2-9-293bab7d5552@analog.com> References: <20240405-iio-backend-axi-dac-v2-0-293bab7d5552@analog.com> In-Reply-To: <20240405-iio-backend-axi-dac-v2-0-293bab7d5552@analog.com> To: , CC: Dragos Bogdan , Lars-Peter Clausen , Michael Hennerich , "Jonathan Cameron" , Rob Herring , "Krzysztof Kozlowski" , Conor Dooley , Olivier Moysan X-Mailer: b4 0.13.0 X-Developer-Signature: v=1; a=ed25519-sha256; t=1712329201; l=12010; i=nuno.sa@analog.com; s=20231116; h=from:subject:message-id; bh=xgAmECrFsUTtJCoji/lM3kzwfT9+MC3hA0V2gf7cX68=; b=+95THANXGfKNXRYHb1Typv/Ol3V3CMkDltLj643MMYxUBNQnMcOAo3Y0OqQUhCJwNguQu3SlQ Eqg6TJ/qks/CdUrexRDGH59KEUz4pJl1R1DSgaa/cc8jwYQBrQ8MSTp X-Developer-Key: i=nuno.sa@analog.com; a=ed25519; pk=3NQwYA013OUYZsmDFBf8rmyyr5iQlxV/9H4/Df83o1E= X-ADIRuleOP-NewSCL: Rule Triggered X-Proofpoint-ORIG-GUID: RYEN8pfUEQ5fxG60HsKfhOfRf7Brg4yn X-Proofpoint-GUID: RYEN8pfUEQ5fxG60HsKfhOfRf7Brg4yn X-Proofpoint-Virus-Version: vendor=baseguard engine=ICAP:2.0.272,Aquarius:18.0.1011,Hydra:6.0.619,FMLib:17.11.176.26 definitions=2024-04-05_16,2024-04-05_01,2023-05-22_02 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 priorityscore=1501 lowpriorityscore=0 clxscore=1015 mlxlogscore=870 impostorscore=0 suspectscore=0 spamscore=0 adultscore=0 phishscore=0 mlxscore=0 malwarescore=0 bulkscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.19.0-2404010003 definitions=main-2404050106 This adds the needed backend ops for supporting a backend inerfacing with an high speed dac. The new ops are: * data_source_set(); * set_sampling_freq(); * extend_chan_spec(); * ext_info_set(); * ext_info_get(). Also to note the new helpers that are meant to be used by the backends when extending an IIO channel (adding extended info): * iio_backend_ext_info_set(); * iio_backend_ext_info_get(). Signed-off-by: Nuno Sa --- drivers/iio/industrialio-backend.c | 179 +++++++++++++++++++++++++++++++++++++ include/linux/iio/backend.h | 49 ++++++++++ 2 files changed, 228 insertions(+) diff --git a/drivers/iio/industrialio-backend.c b/drivers/iio/industrialio-backend.c index 2fea2bbbe47f..ac554798897f 100644 --- a/drivers/iio/industrialio-backend.c +++ b/drivers/iio/industrialio-backend.c @@ -29,6 +29,7 @@ * * Copyright (C) 2023-2024 Analog Devices Inc. */ +#include "asm-generic/errno-base.h" #define dev_fmt(fmt) "iio-backend: " fmt #include @@ -43,10 +44,12 @@ #include #include +#include struct iio_backend { struct list_head entry; const struct iio_backend_ops *ops; + struct device *frontend_dev; struct device *dev; struct module *owner; void *priv; @@ -186,6 +189,44 @@ int iio_backend_data_format_set(struct iio_backend *back, unsigned int chan, } EXPORT_SYMBOL_NS_GPL(iio_backend_data_format_set, IIO_BACKEND); +/** + * iio_backend_data_source_set - Select data source + * @back: Backend device + * @chan: Channel number + * @data: Data source + * + * A given backend may have different sources to stream/sync data. This allows + * to choose that source. + * + * RETURNS: + * 0 on success, negative error number on failure. + */ +int iio_backend_data_source_set(struct iio_backend *back, unsigned int chan, + enum iio_backend_data_source data) +{ + if (data >= IIO_BACKEND_DATA_SOURCE_MAX) + return -EINVAL; + + return iio_backend_op_call(back, data_source_set, chan, data); +} +EXPORT_SYMBOL_NS_GPL(iio_backend_data_source_set, IIO_BACKEND); + +/** + * iio_backend_set_sampling_freq - Set channel sampling rate + * @back: Backend device + * @chan: Channel number + * @sample_rate_hz: Sample rate + * + * RETURNS: + * 0 on success, negative error number on failure. + */ +int iio_backend_set_sampling_freq(struct iio_backend *back, unsigned int chan, + u64 sample_rate_hz) +{ + return iio_backend_op_call(back, set_sample_rate, chan, sample_rate_hz); +} +EXPORT_SYMBOL_NS_GPL(iio_backend_set_sampling_freq, IIO_BACKEND); + static void iio_backend_free_buffer(void *arg) { struct iio_backend_buffer_pair *pair = arg; @@ -231,6 +272,142 @@ int devm_iio_backend_request_buffer(struct device *dev, } EXPORT_SYMBOL_NS_GPL(devm_iio_backend_request_buffer, IIO_BACKEND); +static struct iio_backend *iio_backend_from_indio_dev_parent(const struct device *dev) +{ + struct iio_backend *back = ERR_PTR(-ENODEV), *iter; + + /* + * We deliberately go through all backends even after finding a match. + * The reason is that we want to catch frontend devices which have more + * than one backend in which case returning the first we find is bogus. + * For those cases, frontends need to explicitly define + * get_iio_backend() in struct iio_info. + */ + guard(mutex)(&iio_back_lock); + list_for_each_entry(iter, &iio_back_list, entry) { + if (dev == iter->frontend_dev) { + if (!IS_ERR(back)) { + dev_warn(dev, + "Multiple backends! get_iio_backend() needs to be implemented"); + return ERR_PTR(-ENODEV); + } + + back = iter; + } + } + + return back; +} + +/** + * iio_backend_ext_info_get - IIO ext_info read callback + * @indio_dev: IIO device + * @private: Data private to the driver + * @chan: IIO channel + * @buf: Buffer where to place the attribute data + * + * This helper is intended to be used by backends that extend an IIO channel + * (through iio_backend_extend_chan_spec()) with extended info. In that case, + * backends are not supposed to give their own callbacks (as they would not have + * a way to get the backend from indio_dev). This is the getter. + * + * RETURNS: + * Number of bytes written to buf, negative error number on failure. + */ +ssize_t iio_backend_ext_info_get(struct iio_dev *indio_dev, uintptr_t private, + const struct iio_chan_spec *chan, char *buf) +{ + struct iio_backend *back; + + if (indio_dev->info->get_iio_backend) + back = indio_dev->info->get_iio_backend(indio_dev, chan); + else + back = iio_backend_from_indio_dev_parent(indio_dev->dev.parent); + if (IS_ERR(back)) + return PTR_ERR(back); + + return iio_backend_op_call(back, ext_info_get, private, chan, buf); +} +EXPORT_SYMBOL_NS_GPL(iio_backend_ext_info_get, IIO_BACKEND); + +/** + * iio_backend_ext_info_set - IIO ext_info write callback + * @indio_dev: IIO device + * @private: Data private to the driver + * @chan: IIO channel + * @buf: Buffer holding the sysfs attribute + * @len: Buffer length + * + * This helper is intended to be used by backends that extend an IIO channel + * (trough iio_backend_extend_chan_spec()) with extended info. In that case, + * backends are not supposed to give their own callbacks (as they would not have + * a way to get the backend from indio_dev). This is the setter. + * + * RETURNS: + * Buffer length on success, negative error number on failure. + */ +ssize_t iio_backend_ext_info_set(struct iio_dev *indio_dev, uintptr_t private, + const struct iio_chan_spec *chan, + const char *buf, size_t len) +{ + struct iio_backend *back; + + if (indio_dev->info->get_iio_backend) + back = indio_dev->info->get_iio_backend(indio_dev, chan); + else + back = iio_backend_from_indio_dev_parent(indio_dev->dev.parent); + if (IS_ERR(back)) + return PTR_ERR(back); + + return iio_backend_op_call(back, ext_info_set, private, chan, buf, len); +} +EXPORT_SYMBOL_NS_GPL(iio_backend_ext_info_set, IIO_BACKEND); + +/** + * iio_backend_extend_chan_spec - Extend an IIO channel + * @indio_dev: IIO device + * @back: Backend device + * @chan: IIO channel + * + * Some backends may have their own functionalities and hence capable of + * extending a frontend's channel. + * + * RETURNS: + * 0 on success, negative error number on failure. + */ +int iio_backend_extend_chan_spec(struct iio_dev *indio_dev, + struct iio_backend *back, + struct iio_chan_spec *chan) +{ + const struct iio_chan_spec_ext_info *frontend_ext_info = chan->ext_info; + const struct iio_chan_spec_ext_info *back_ext_info; + int ret; + + ret = iio_backend_op_call(back, extend_chan_spec, chan); + if (ret) + return ret; + /* + * Let's keep things simple for now. Don't allow to overwrite the + * frontend's extended info. If ever needed, we can support appending + * it. + */ + if (frontend_ext_info && chan->ext_info != frontend_ext_info) + return -EOPNOTSUPP; + if (!chan->ext_info) + return 0; + + /* Don't allow backends to get creative and force their own handlers */ + for (back_ext_info = chan->ext_info; back_ext_info->name; back_ext_info++) { + if (back_ext_info->read != iio_backend_ext_info_get) + return -EINVAL; + if (back_ext_info->write != iio_backend_ext_info_set) + return -EINVAL; + } + + return 0; +} +EXPORT_SYMBOL_NS_GPL(iio_backend_extend_chan_spec, IIO_BACKEND); + static void iio_backend_release(void *arg) { struct iio_backend *back = arg; @@ -263,6 +440,8 @@ static int __devm_iio_backend_get(struct device *dev, struct iio_backend *back) "Could not link to supplier(%s)\n", dev_name(back->dev)); + back->frontend_dev = dev; + dev_dbg(dev, "Found backend(%s) device\n", dev_name(back->dev)); return 0; diff --git a/include/linux/iio/backend.h b/include/linux/iio/backend.h index a6d79381866e..9d144631134d 100644 --- a/include/linux/iio/backend.h +++ b/include/linux/iio/backend.h @@ -4,6 +4,7 @@ #include +struct iio_chan_spec; struct fwnode_handle; struct iio_backend; struct device; @@ -15,6 +16,26 @@ enum iio_backend_data_type { IIO_BACKEND_DATA_TYPE_MAX }; +enum iio_backend_data_source { + IIO_BACKEND_INTERNAL_CONTINUOS_WAVE, + IIO_BACKEND_EXTERNAL, + IIO_BACKEND_DATA_SOURCE_MAX +}; + +/** + * IIO_BACKEND_EX_INFO - Helper for an IIO extended channel attribute + * @_name: Attribute name + * @_shared: Whether the attribute is shared between all channels + * @_what: Data private to the driver + */ +#define IIO_BACKEND_EX_INFO(_name, _shared, _what) { \ + .name = (_name), \ + .shared = (_shared), \ + .read = iio_backend_ext_info_get, \ + .write = iio_backend_ext_info_set, \ + .private = (_what), \ +} + /** * struct iio_backend_data_fmt - Backend data format * @type: Data type. @@ -35,8 +56,13 @@ struct iio_backend_data_fmt { * @chan_enable: Enable one channel. * @chan_disable: Disable one channel. * @data_format_set: Configure the data format for a specific channel. + * @data_source_set: Configure the data source for a specific channel. + * @set_sample_rate: Configure the sampling rate for a specific channel. * @request_buffer: Request an IIO buffer. * @free_buffer: Free an IIO buffer. + * @extend_chan_spec: Extend an IIO channel. + * @ext_info_set: Extended info setter. + * @ext_info_get: Extended info getter. **/ struct iio_backend_ops { int (*enable)(struct iio_backend *back); @@ -45,10 +71,21 @@ struct iio_backend_ops { int (*chan_disable)(struct iio_backend *back, unsigned int chan); int (*data_format_set)(struct iio_backend *back, unsigned int chan, const struct iio_backend_data_fmt *data); + int (*data_source_set)(struct iio_backend *back, unsigned int chan, + enum iio_backend_data_source data); + int (*set_sample_rate)(struct iio_backend *back, unsigned int chan, + u64 sample_rate_hz); struct iio_buffer *(*request_buffer)(struct iio_backend *back, struct iio_dev *indio_dev); void (*free_buffer)(struct iio_backend *back, struct iio_buffer *buffer); + int (*extend_chan_spec)(struct iio_backend *back, + struct iio_chan_spec *chan); + int (*ext_info_set)(struct iio_backend *back, uintptr_t private, + const struct iio_chan_spec *chan, + const char *buf, size_t len); + int (*ext_info_get)(struct iio_backend *back, uintptr_t private, + const struct iio_chan_spec *chan, char *buf); }; int iio_backend_chan_enable(struct iio_backend *back, unsigned int chan); @@ -56,10 +93,22 @@ int iio_backend_chan_disable(struct iio_backend *back, unsigned int chan); int devm_iio_backend_enable(struct device *dev, struct iio_backend *back); int iio_backend_data_format_set(struct iio_backend *back, unsigned int chan, const struct iio_backend_data_fmt *data); +int iio_backend_data_source_set(struct iio_backend *back, unsigned int chan, + enum iio_backend_data_source data); +int iio_backend_set_sampling_freq(struct iio_backend *back, unsigned int chan, + u64 sample_rate_hz); int devm_iio_backend_request_buffer(struct device *dev, struct iio_backend *back, struct iio_dev *indio_dev); +ssize_t iio_backend_ext_info_set(struct iio_dev *indio_dev, uintptr_t private, + const struct iio_chan_spec *chan, + const char *buf, size_t len); +ssize_t iio_backend_ext_info_get(struct iio_dev *indio_dev, uintptr_t private, + const struct iio_chan_spec *chan, char *buf); +int iio_backend_extend_chan_spec(struct iio_dev *indio_dev, + struct iio_backend *back, + struct iio_chan_spec *chan); void *iio_backend_get_priv(const struct iio_backend *conv); struct iio_backend *devm_iio_backend_get(struct device *dev, const char *name); struct iio_backend *