kernel/drivers/iio/industrialio-buffer.c, branch linux-6.18.y

iio: buffer: Fix wait_queue not being removed

2026-03-19T15:08:47Z

commit 064234044056c93a3719d6893e6e5a26a94a61b6 upstream. In the edge case where the IIO device is unregistered while we're buffering, we were directly returning an error without removing the wait queue. Instead, set 'ret' and break out of the loop. Fixes: 9eeee3b0bf19 ("iio: Add output buffer support") Signed-off-by: Nuno Sá Reviewed-by: David Lechner Cc: Signed-off-by: Jonathan Cameron Signed-off-by: Greg Kroah-Hartman

iio: buffer: support getting dma channel from the buffer

2025-10-13T07:38:08Z

Add a new buffer accessor .get_dma_dev() in order to get the struct device responsible for actually providing the dma channel. We cannot assume that we can use the parent of the IIO device for mapping the DMA buffer. This becomes important on systems (like the Xilinx/AMD zynqMP Ultrascale) where memory (or part of it) is mapped above the 32 bit range. On such systems and given that a device by default has a dma mask of 32 bits we would then need to rely on bounce buffers (to swiotlb) for mapping memory above the dma mask limit. In the process, add an iio_buffer_get_dma_dev() helper function to get the proper DMA device. Cc: stable@vger.kernel.org Reviewed-by: David Lechner Signed-off-by: Nuno Sá Signed-off-by: Jonathan Cameron

iio: core: mark scan_timestamp as __private

2024-12-28T14:28:14Z

Since there are no more direct accesses to the indio_dev->scan_timestamp value, it can be marked as __private and use the macro ACCESS_PRIVATE() in order to access it. Like this, static checkers will be able to inform in case someone tries to either write to the value, or read its value directly. Signed-off-by: Vasileios Amoiridis Link: https://patch.msgid.link/20241214191421.94172-5-vassilisamir@gmail.com Signed-off-by: Jonathan Cameron

module: Convert symbol namespace to string literal

2024-12-02T19:34:44Z

Clean up the existing export namespace code along the same lines of commit 33def8498fdd ("treewide: Convert macro and uses of __section(foo) to __section("foo")") and for the same reason, it is not desired for the namespace argument to be a macro expansion itself. Scripted using git grep -l -e MODULE_IMPORT_NS -e EXPORT_SYMBOL_NS | while read file; do awk -i inplace ' /^#define EXPORT_SYMBOL_NS/ { gsub(/__stringify$ns$/, "ns"); print; next; } /^#define MODULE_IMPORT_NS/ { gsub(/__stringify$ns$/, "ns"); print; next; } /MODULE_IMPORT_NS/ { $0 = gensub(/MODULE_IMPORT_NS$([^)]*)$/, "MODULE_IMPORT_NS(\"\\1\")", "g"); } /EXPORT_SYMBOL_NS/ { if ($0 ~ /(EXPORT_SYMBOL_NS[^(]*)$([^,]+),/) { if ($0 !~ /(EXPORT_SYMBOL_NS[^(]*)\(([^,]+), ([^)]+)$/ && $0 !~ /(EXPORT_SYMBOL_NS[^(]*)/ && $0 !~ /^my/) { getline line; gsub(/[[:space:]]*\\$/, ""); gsub(/[[:space:]]/, "", line); $0 = $0 " " line; } $0 = gensub(/(EXPORT_SYMBOL_NS[^(]*)$([^,]+), ([^)]+)$/, "\\1(\\2, \"\\3\")", "g"); } } { print }' $file; done Requested-by: Masahiro Yamada Signed-off-by: Peter Zijlstra (Intel) Link: https://mail.google.com/mail/u/2/#inbox/FMfcgzQXKWgMmjdFwwdsfgxzKpVHWPlc Acked-by: Greg KH Signed-off-by: Linus Torvalds

iio: core: annotate masklength as __private

2024-08-03T09:13:43Z

Now that all users are using the proper accessors, we can mark masklength as __private so that no one tries to write. We also get help from checkers in warning us in case someone does it. To access the private field from IIO core code, we need to use the ACCESS_PRIVATE() macro. Signed-off-by: Nuno Sa Link: https://patch.msgid.link/20240726-dev-iio-masklength-private3-v1-23-82913fc0fb87@analog.com Signed-off-by: Jonathan Cameron

iio: buffer: make use of iio_get_masklength()

2024-07-29T19:31:07Z

Use iio_get_masklength() to access '.masklength' so it can be annotated as __private when there are no more direct users of it. While at it, remove some unneeded line breaks. Signed-off-by: Nuno Sa Reviewed-by: Alexandru Ardelean Link: https://patch.msgid.link/20240702-dev-iio-masklength-private-v1-3-98193bf536a6@analog.com Signed-off-by: Jonathan Cameron

iio: core: Add new DMABUF interface infrastructure

2024-06-30T10:29:17Z

Add the necessary infrastructure to the IIO core to support a new optional DMABUF based interface. With this new interface, DMABUF objects (externally created) can be attached to a IIO buffer, and subsequently used for data transfer. A userspace application can then use this interface to share DMABUF objects between several interfaces, allowing it to transfer data in a zero-copy fashion, for instance between IIO and the USB stack. The userspace application can also memory-map the DMABUF objects, and access the sample data directly. The advantage of doing this vs. the read() interface is that it avoids an extra copy of the data between the kernel and userspace. This is particularly userful for high-speed devices which produce several megabytes or even gigabytes of data per second. As part of the interface, 3 new IOCTLs have been added: IIO_BUFFER_DMABUF_ATTACH_IOCTL(int fd): Attach the DMABUF object identified by the given file descriptor to the buffer. IIO_BUFFER_DMABUF_DETACH_IOCTL(int fd): Detach the DMABUF object identified by the given file descriptor from the buffer. Note that closing the IIO buffer's file descriptor will automatically detach all previously attached DMABUF objects. IIO_BUFFER_DMABUF_ENQUEUE_IOCTL(struct iio_dmabuf *): Request a data transfer to/from the given DMABUF object. Its file descriptor, as well as the transfer size and flags are provided in the "iio_dmabuf" structure. These three IOCTLs have to be performed on the IIO buffer's file descriptor, obtained using the IIO_BUFFER_GET_FD_IOCTL() ioctl. Signed-off-by: Paul Cercueil Co-developed-by: Nuno Sa Signed-off-by: Nuno Sa Link: https://patch.msgid.link/20240620122726.41232-4-paul@crapouillou.net Signed-off-by: Jonathan Cameron

iio: add support for multiple scan types per channel

2024-06-04T18:53:08Z

This adds new fields to the iio_channel structure to support multiple scan types per channel. This is useful for devices that support multiple resolution modes or other modes that require different data formats of the raw data. To make use of this, drivers need to implement the new callback get_current_scan_type() to resolve the scan type for a given channel based on the current state of the driver. There is a new scan_type_ext field in the iio_channel structure that should be used to store the scan types for any channel that has more than one. There is also a new flag has_ext_scan_type that acts as a type discriminator for the scan_type/ext_scan_type union. A union is used so that we don't grow the size of the iio_channel structure and also makes it clear that scan_type and ext_scan_type are mutually exclusive. The buffer code is the only code in the IIO core code that is using the scan_type field. This patch updates the buffer code to use the new iio_channel_validate_scan_type() function to ensure it is returning the correct scan type for the current state of the device when reading the sysfs attributes. The buffer validation code is also update to validate any additional scan types that are set in the scan_type_ext field. Part of that code is refactored to a new function to avoid duplication. Some userspace tools may need to be updated to re-read the scan type after writing any other attribute. During testing, we noticed that we had to restart iiod to get it to re-read the scan type after enabling oversampling on the ad7380 driver. Signed-off-by: David Lechner Reviewed-by: Nuno Sa Link: https://lore.kernel.org/r/20240530-iio-add-support-for-multiple-scan-types-v3-3-cbc4acea2cfa@baylibre.com Signed-off-by: Jonathan Cameron

iio: buffer: use struct iio_scan_type to simplify code

2024-06-04T18:53:08Z

By using struct iio_scan_type, we can simplify the code by removing lots of duplicate pointer dereferences. This make the code a bit easier to read. This also prepares for a future where channels may have more than one scan_type. Signed-off-by: David Lechner Reviewed-by: Nuno Sa Link: https://lore.kernel.org/r/20240530-iio-add-support-for-multiple-scan-types-v3-2-cbc4acea2cfa@baylibre.com Signed-off-by: Jonathan Cameron

iio: buffer: initialize masklength accumulator to 0

2024-04-29T19:53:24Z

Since masklength is marked as [INTERN], no drivers should assign it and the value will always be 0. Therefore, the local ml accumulator variable in iio_buffers_alloc_sysfs_and_mask() will always start out as 0. This changes the code to explicitly set ml to 0 to make it clear that drivers should not be trying to override the masklength field. Signed-off-by: David Lechner Link: https://lore.kernel.org/r/20240425-b4-iio-masklength-cleanup-v1-3-d3d16318274d@baylibre.com Signed-off-by: Jonathan Cameron