kernel/drivers/iio/buffer/industrialio-buffer-dmaengine.c, branch linux-6.9.y

iio: buffer-dmaengine: export buffer alloc and free functions

2024-02-19T19:32:21Z

Export iio_dmaengine_buffer_free() and iio_dmaengine_buffer_alloc(). This is in preparation of introducing IIO backends support. This will allow us to allocate a buffer and control it's lifetime from a device different from the one holding the DMA firmware properties. Effectively, in this case the struct device holding the firmware information about the DMA channels is not the same as iio_dev->dev.parent (typical case). While at it, namespace the buffer-dmaengine exports and update the current user of these buffers. Signed-off-by: Nuno Sa Link: https://lore.kernel.org/r/20240210-iio-backend-v11-4-f5242a5fb42a@analog.com Reviewed-by: Andy Shevchenko Signed-off-by: Jonathan Cameron

iio: buffer-dmaengine: make use of the 'struct device *' argument

2024-01-23T22:06:56Z

Respect the @dev argument in devm_iio_dmaengine_buffer_setup() and bind the IIO DMA buffer lifetime to that device. For the only user of this function, the IIO parent device is the struct device being passed to the API so no real fix in here (just consistency with other IIO APIs). Signed-off-by: Nuno Sa Reviewed-by: David Lechner Link: https://lore.kernel.org/r/20240109-dmaengine_use_device-v1-1-1cbdb7fe9f29@analog.com Signed-off-by: Jonathan Cameron

iio: Don't silently expect attribute types

2022-11-23T19:44:04Z

The iio_triggered_buffer_setup_ext() and the devm_iio_kfifo_buffer_setup_ext() were changed by commit 15097c7a1adc ("iio: buffer: wrap all buffer attributes into iio_dev_attr") to silently expect that all attributes given in buffer_attrs array are device-attributes. This expectation was not forced by the API - and some drivers did register attributes created by IIO_CONST_ATTR(). When using IIO_CONST_ATTRs the added attribute "wrapping" does not copy the pointer to stored string constant and when the sysfs file is read the kernel will access to invalid location. Change the function signatures to expect an array of iio_dev_attrs to avoid similar errors in the future. Merge conflict resolved whilst applying due to patch crossing with two new drivers (kx022a accelerometer and ad4130 ADC). Signed-off-by: Matti Vaittinen Tested-by: Claudiu Beznea Link: https://lore.kernel.org/r/63f54787a684eb1232f1c5d275a09c786987fe4a.1664782676.git.mazziesaccount@gmail.com Signed-off-by: Jonathan Cameron

iio: dmaengine-buffer: Use sysfs_emit()

2022-01-23T18:03:36Z

sysfs_emit() is preferred over raw s*printf() for sysfs attributes since it knows about the sysfs buffer specifics and has some built-in checks for size and alignment. Use sysfs_emit() for the `length_align_bytes` buffer attribute. Signed-off-by: Lars-Peter Clausen Link: https://lore.kernel.org/r/20211216185217.1054495-3-lars@metafoo.de Signed-off-by: Jonathan Cameron

iio: buffer-dma: Use round_down() instead of rounddown()

2021-11-27T15:12:44Z

We know that the buffer's alignment will always be a power of two; therefore, we can use the faster round_down() macro. Signed-off-by: Paul Cercueil Reviewed-by: Alexandru Ardelean Link: https://lore.kernel.org/r/20211115141925.60164-4-paul@crapouillou.net Signed-off-by: Jonathan Cameron

iio: buffer-dmaengine: simplify __devm_iio_dmaengine_buffer_free()

2021-05-17T12:49:06Z

Use devm_add_action_or_reset() instead of devres_alloc() and devres_add(), which works the same. This will simplify the code. There is no functional changes. Signed-off-by: Yicong Yang Reviewed-by: Lars-Peter Clausen Reviewed-by: Nuno Sa Reviewed-by: Andy Shevchenko Link: https://lore.kernel.org/r/1617881896-3164-3-git-send-email-yangyicong@hisilicon.com Signed-off-by: Jonathan Cameron

iio: buffer: introduce support for attaching more IIO buffers

2021-03-11T20:47:05Z

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

iio: buffer: dmaengine: obtain buffer object from attribute

2021-03-11T20:47:04Z

The reference to the IIO buffer object is stored on the attribute object. So we need to unwind it to obtain it. Signed-off-by: Alexandru Ardelean Link: https://lore.kernel.org/r/20210215104043.91251-16-alexandru.ardelean@analog.com Signed-off-by: Jonathan Cameron

iio: buffer-dma,adi-axi-adc: introduce devm_iio_dmaengine_buffer_setup()

2021-03-11T20:47:02Z

This change does a conversion of the devm_iio_dmaengine_buffer_alloc() to devm_iio_dmaengine_buffer_setup(). This will allocate an IIO DMA buffer and attach it to the IIO device, similar to devm_iio_triggered_buffer_setup() (though the underlying code is different, the final logic is the same). Since the only user of the devm_iio_dmaengine_buffer_alloc() was the adi-axi-adc driver, this change does the replacement in a single go in the driver. Signed-off-by: Alexandru Ardelean Link: https://lore.kernel.org/r/20210215104043.91251-7-alexandru.ardelean@analog.com Signed-off-by: Jonathan Cameron

iio: buffer: dmaengine: unwrap the use of iio_buffer_set_attrs()

2020-11-21T14:52:57Z

The iio_buffer_set_attrs() helper will be removed in this series. So, just assign the attributes of the DMAEngine buffer logic directly. This is IIO buffer core context, so there is direct access to the buffer->attrs object. Signed-off-by: Alexandru Ardelean Reviewed-by: Andy Shevchenko Link: https://lore.kernel.org/r/20200929125949.69934-2-alexandru.ardelean@analog.com Signed-off-by: Jonathan Cameron