Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752475AbaJBMcJ (ORCPT ); Thu, 2 Oct 2014 08:32:09 -0400 Received: from ns.mm-sol.com ([37.157.136.199]:47242 "EHLO extserv.mm-sol.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752396AbaJBMcG (ORCPT ); Thu, 2 Oct 2014 08:32:06 -0400 From: "Ivan T. Ivanov" To: Jonathan Cameron Cc: "Ivan T. Ivanov" , Lars-Peter Clausen , Sachin Kamat , Srinivas Pandruvada , John Stultz , linux-iio@vger.kernel.org, svarbanov@mm-sol.com, linux-kernel@vger.kernel.org, linux-arm-msm@vger.kernel.org Subject: [PATCH] iio: inkern: Add of_xlate function to struct iio_dev Date: Thu, 2 Oct 2014 15:32:08 +0300 Message-Id: <1412253128-32165-1-git-send-email-iivanov@mm-sol.com> X-Mailer: git-send-email 1.9.1 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org When #iio-cells is greater than '0', the driver could provide a custom of_xlate function that reads the *args* and returns the appropriate index in registered IIO channels array. Add simple translation function, suitable for the most 1:1 mapped channels in IIO chips, and use it when driver did not provide custom implementation. Signed-off-by: Ivan T. Ivanov --- drivers/iio/inkern.c | 32 +++++++++++++++++++++++++++----- include/linux/iio/iio.h | 8 ++++++++ 2 files changed, 35 insertions(+), 5 deletions(-) diff --git a/drivers/iio/inkern.c b/drivers/iio/inkern.c index f084610..6c3e478 100644 --- a/drivers/iio/inkern.c +++ b/drivers/iio/inkern.c @@ -100,6 +100,28 @@ static int iio_dev_node_match(struct device *dev, void *data) return dev->of_node == data && dev->type == &iio_device_type; } +/** + * __of_iio_simple_xlate - translate iiospec to the IIO channel index + * @indio_dev: pointer to the iio_dev structure + * @iiospec: IIO specifier as found in the device tree + * + * This is simple translation function, suitable for the most 1:1 mapped + * channels in IIO chips. This function performs only one sanity check: + * whether IIO index is less than num_channels (that is specified in the + * iio_dev). + */ +static int __of_iio_simple_xlate(struct iio_dev *indio_dev, + const struct of_phandle_args *iiospec) +{ + if (!iiospec->args_count) + return 0; + + if (iiospec->args[0] >= indio_dev->num_channels) + return -EINVAL; + + return iiospec->args[0]; +} + static int __of_iio_channel_get(struct iio_channel *channel, struct device_node *np, int index) { @@ -122,18 +144,18 @@ static int __of_iio_channel_get(struct iio_channel *channel, indio_dev = dev_to_iio_dev(idev); channel->indio_dev = indio_dev; - index = iiospec.args_count ? iiospec.args[0] : 0; - if (index >= indio_dev->num_channels) { - err = -EINVAL; + if (!indio_dev->of_xlate) + indio_dev->of_xlate = __of_iio_simple_xlate; + index = indio_dev->of_xlate(indio_dev, &iiospec); + if (index < 0) goto err_put; - } channel->channel = &indio_dev->channels[index]; return 0; err_put: iio_device_put(indio_dev); - return err; + return index; } static struct iio_channel *of_iio_channel_get(struct device_node *np, int index) diff --git a/include/linux/iio/iio.h b/include/linux/iio/iio.h index 15dc6bc..d5bb219 100644 --- a/include/linux/iio/iio.h +++ b/include/linux/iio/iio.h @@ -13,6 +13,7 @@ #include #include #include +#include /* IIO TODO LIST */ /* * Provide means of adjusting timer accuracy. @@ -413,6 +414,11 @@ struct iio_buffer_setup_ops { * @currentmode: [DRIVER] current operating mode * @dev: [DRIVER] device structure, should be assigned a parent * and owner + * @of_xlate: [DRIVER] function pointer to obtain channel specifier + * index. When #iio-cells is greater than '0', the driver + * could provide a custom of_xlate function that reads + * the *args* and returns the appropriate index in + * registered IIO channels array. * @event_interface: [INTERN] event chrdevs associated with interrupt lines * @buffer: [DRIVER] any buffer present * @buffer_list: [INTERN] list of all buffers currently attached @@ -451,6 +457,8 @@ struct iio_dev { int currentmode; struct device dev; + int (*of_xlate)(struct iio_dev *indio_dev, + const struct of_phandle_args *iiospec); struct iio_event_interface *event_interface; struct iio_buffer *buffer; -- 1.9.1 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/