From ee708e6baacd3afdace9b721c25fbbe106cebb94 Mon Sep 17 00:00:00 2001 From: Alexandru Ardelean Date: Mon, 15 Feb 2021 12:40:38 +0200 Subject: iio: buffer: introduce support for attaching more IIO buffers With this change, calling iio_device_attach_buffer() will actually attach more buffers. Right now this doesn't do any validation of whether a buffer is attached twice; maybe that can be added later (if needed). Attaching a buffer more than once should yield noticeably bad results. The first buffer is the legacy buffer, so a reference is kept to it. At this point, accessing the data for the extra buffers (that are added after the first one) isn't possible yet. The iio_device_attach_buffer() is also changed to return an error code, which for now is -ENOMEM if the array could not be realloc-ed for more buffers. To adapt to this new change iio_device_attach_buffer() is called last in all place where it's called. The realloc failure is a bit difficult to handle during un-managed calls when unwinding, so it's better to have this as the last error in the setup_buffer calls. At this point, no driver should call iio_device_attach_buffer() directly, it should call one of the {devm_}iio_triggered_buffer_setup() or devm_iio_kfifo_buffer_setup() or devm_iio_dmaengine_buffer_setup() functions. This makes iio_device_attach_buffer() a bit easier to handle. Signed-off-by: Alexandru Ardelean Link: https://lore.kernel.org/r/20210215104043.91251-20-alexandru.ardelean@analog.com Signed-off-by: Jonathan Cameron --- drivers/iio/buffer/industrialio-triggered-buffer.c | 10 +++++++--- 1 file changed, 7 insertions(+), 3 deletions(-) (limited to 'drivers/iio/buffer/industrialio-triggered-buffer.c') diff --git a/drivers/iio/buffer/industrialio-triggered-buffer.c b/drivers/iio/buffer/industrialio-triggered-buffer.c index 92b8aea3e063..b2b1b7d27af4 100644 --- a/drivers/iio/buffer/industrialio-triggered-buffer.c +++ b/drivers/iio/buffer/industrialio-triggered-buffer.c @@ -50,8 +50,6 @@ int iio_triggered_buffer_setup_ext(struct iio_dev *indio_dev, goto error_ret; } - iio_device_attach_buffer(indio_dev, buffer); - indio_dev->pollfunc = iio_alloc_pollfunc(h, thread, IRQF_ONESHOT, @@ -72,10 +70,16 @@ int iio_triggered_buffer_setup_ext(struct iio_dev *indio_dev, buffer->attrs = buffer_attrs; + ret = iio_device_attach_buffer(indio_dev, buffer); + if (ret < 0) + goto error_dealloc_pollfunc; + return 0; +error_dealloc_pollfunc: + iio_dealloc_pollfunc(indio_dev->pollfunc); error_kfifo_free: - iio_kfifo_free(indio_dev->buffer); + iio_kfifo_free(buffer); error_ret: return ret; } -- cgit v1.2.3