From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-qt0-f193.google.com ([209.85.216.193]:42495 "EHLO mail-qt0-f193.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751112AbdLEU5F (ORCPT ); Tue, 5 Dec 2017 15:57:05 -0500 Received: by mail-qt0-f193.google.com with SMTP id g9so4075125qth.9 for ; Tue, 05 Dec 2017 12:57:04 -0800 (PST) From: mfornero@gmail.com To: jic23@kernel.org, lars@metafoo.de Cc: linux-iio@vger.kernel.org, Matt Fornero Subject: [PATCH v2] iio: buffer: Expose data available Date: Tue, 5 Dec 2017 15:56:56 -0500 Message-Id: <1512507416-21856-1-git-send-email-mfornero@gmail.com> In-Reply-To: <1512161180-30116-1-git-send-email-mfornero@gmail.com> References: <1512161180-30116-1-git-send-email-mfornero@gmail.com> Sender: linux-iio-owner@vger.kernel.org List-Id: linux-iio@vger.kernel.org From: Matt Fornero Add a sysfs attribute that exposes buffer data available to userspace. This attribute can be checked at runtime to determine the overall buffer fill level (across all allocated buffers). Signed-off-by: Matt Fornero --- v1 -> v2: - Use iio_buffer_data_available() for all buffers instead of only DMA buffers drivers/iio/industrialio-buffer.c | 15 +++++++++++++++ 1 file changed, 15 insertions(+) diff --git a/drivers/iio/industrialio-buffer.c b/drivers/iio/industrialio-buffer.c index d80f830..e7bdfa3 100644 --- a/drivers/iio/industrialio-buffer.c +++ b/drivers/iio/industrialio-buffer.c @@ -1121,6 +1121,18 @@ static ssize_t iio_buffer_store_watermark(struct device *dev, return ret ? ret : len; } +static ssize_t iio_dma_show_data_available(struct device *dev, + struct device_attribute *attr, + char *buf) +{ + struct iio_dev *indio_dev = dev_to_iio_dev(dev); + size_t bytes; + + bytes = iio_buffer_data_available(indio_dev->buffer); + + return sprintf(buf, "%llu\n", (unsigned long long)bytes); +} + static DEVICE_ATTR(length, S_IRUGO | S_IWUSR, iio_buffer_read_length, iio_buffer_write_length); static struct device_attribute dev_attr_length_ro = __ATTR(length, @@ -1131,11 +1143,14 @@ static DEVICE_ATTR(watermark, S_IRUGO | S_IWUSR, iio_buffer_show_watermark, iio_buffer_store_watermark); static struct device_attribute dev_attr_watermark_ro = __ATTR(watermark, S_IRUGO, iio_buffer_show_watermark, NULL); +static DEVICE_ATTR(data_available, S_IRUGO, + iio_dma_show_data_available, NULL); static struct attribute *iio_buffer_attrs[] = { &dev_attr_length.attr, &dev_attr_enable.attr, &dev_attr_watermark.attr, + &dev_attr_data_available.attr, }; int iio_buffer_alloc_sysfs_and_mask(struct iio_dev *indio_dev) -- 1.8.3.1