mirror of
https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
synced 2026-05-08 12:52:40 -04:00
e19bdbaa31
DMA operates in Double Buffer Mode (DBM) when the transfer is cyclic and there are at least two periods. When DBM is enabled, the DMA toggles between two memory targets (SxM0AR and SxM1AR), indicated by the SxSCR.CT bit (Current Target). There is no need to update the next memory address if two periods are configured, as SxM0AR and SxM1AR are already properly set up before the transfer begins in the stm32_dma_start_transfer() function. This avoids unnecessary updates to SxM0AR/SxM1AR, thereby preventing potential Transfer Errors. Specifically, when the channel is enabled, SxM0AR and SxM1AR can only be written if SxSCR.CT=1 and SxSCR.CT=0, respectively. Otherwise, a Transfer Error interrupt is triggered, and the stream is automatically disabled. Signed-off-by: Amelie Delaunay <amelie.delaunay@foss.st.com> Link: https://lore.kernel.org/r/20250624-stm32_dma_dbm_fix-v1-1-337c40d6c93e@foss.st.com Signed-off-by: Vinod Koul <vkoul@kernel.org>
Linux kernel
============
There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.
In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``. The formatted documentation can also be read online at:
https://www.kernel.org/doc/html/latest/
There are various text files in the Documentation/ subdirectory,
several of them using the reStructuredText markup notation.
Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.