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authorLinus Torvalds <torvalds@linux-foundation.org>2026-08-19 10:09:22 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2026-08-19 10:09:22 -0700
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Merge tag 'media/v7.3-1' of git://git.kernel.org/pub/scm/linux/kernel/git/mchehab/linux-mediagrafted
Pull media updates from Mauro Carvalho Chehab: - v4l2-core: added ISP statistics support and per-block validation - v4l2-core: Allow unknown HDR10 white point and luminance - New camera sensors: Sony IMX678 and IMX471m, Himax HM1092 IR sensor - New codec: Milos: VPU v2.0 codec support - isp driver: gained support for Dreamchip RPPX1 ISP framework - vsp1 driver: gained support for RZ/T2H and RZ/N2H - Novalake driver: gained CVS support for new NVL hardware - dvb-core: fix feed leak on failed DMX_ADD_PID - several driver fixes, cleanups and minor improvements * tag 'media/v7.3-1' of git://git.kernel.org/pub/scm/linux/kernel/git/mchehab/linux-media: (308 commits) media: ipu-bridge: check all DMI entries when overriding sensor rotation media: v4l2-async: avoid deleting unlinked ASC entry on link error media: rzg2l-cru: Align bytesperline to hardware DMA stride requirement media: intel/ipu6: fix async notifier cleanup leak on parse error media: staging/ipu7: fix async notifier UAF on probe error path media: amd: isp4: fix self-deadlock in isp4sd_pwron_and_init() error path media: amd: isp4: release partial allocations in isp4if_alloc_fw_gpumem() media: rcar-isp: Fix VSPX reference leaks media: rcar-isp: Release ISPCORE resources media: i2c: imx415: Release runtime PM reference on VBLANK error media: i2c: imx415: Return test pattern write errors media: renesas: vsp1: Declare index variables in for loop statement media: renesas: vsp1: Make reset control optional to support platforms without a reset line media: dt-bindings: media: renesas,vsp1: Document RZ/T2H and RZ/N2H SoCs media: dt-bindings: media: renesas,fcp: Document RZ/T2H and RZ/N2H SoCs media: nxp: imx8-isi: Add additional 32-bit RGB format support media: nxp: imx8-isi: Add 16-bit raw Bayer format support media: nxp: imx8-isi: Implement per-stream reference counting for multiplexed streams media: nxp: imx8-isi: Use BIT_ULL() for 64-bit stream masks media: nxp: imx8-isi: Correct color map between V4L2 and ISI ...
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+In-kernel API for FPGA Programming
+==================================
+
+Overview
+--------
+
+The in-kernel API for FPGA programming is a combination of APIs from
+FPGA manager, bridge, and regions. The actual function used to
+trigger FPGA programming is fpga_region_program_fpga().
+
+fpga_region_program_fpga() uses functionality supplied by
+the FPGA manager and bridges. It will:
+
+ * lock the region's mutex
+ * lock the mutex of the region's FPGA manager
+ * build a list of FPGA bridges if a method has been specified to do so
+ * disable the bridges
+ * program the FPGA using info passed in :c:expr:`fpga_region->info`.
+ * re-enable the bridges
+ * release the locks
+
+The struct fpga_image_info specifies what FPGA image to program. It is
+allocated/freed by fpga_image_info_alloc() and freed with
+fpga_image_info_free()
+
+How to program an FPGA using a region
+-------------------------------------
+
+When the FPGA region driver probed, it was given a pointer to an FPGA manager
+driver so it knows which manager to use. The region also either has a list of
+bridges to control during programming or it has a pointer to a function that
+will generate that list. Here's some sample code of what to do next::
+
+ #include <linux/fpga/fpga-mgr.h>
+ #include <linux/fpga/fpga-region.h>
+
+ struct fpga_image_info *info;
+ int ret;
+
+ /*
+ * First, alloc the struct with information about the FPGA image to
+ * program.
+ */
+ info = fpga_image_info_alloc(dev);
+ if (!info)
+ return -ENOMEM;
+
+ /* Set flags as needed, such as: */
+ info->flags = FPGA_MGR_PARTIAL_RECONFIG;
+
+ /*
+ * Indicate where the FPGA image is. This is pseudo-code; you're
+ * going to use one of these three.
+ */
+ if (image is in a scatter gather table) {
+
+ info->sgt = [your scatter gather table]
+
+ } else if (image is in a buffer) {
+
+ info->buf = [your image buffer]
+ info->count = [image buffer size]
+
+ } else if (image is in a firmware file) {
+
+ info->firmware_name = devm_kstrdup(dev, firmware_name,
+ GFP_KERNEL);
+
+ }
+
+ /* Add info to region and do the programming */
+ region->info = info;
+ ret = fpga_region_program_fpga(region);
+
+ /* Deallocate the image info if you're done with it */
+ region->info = NULL;
+ fpga_image_info_free(info);
+
+ if (ret)
+ return ret;
+
+ /* Now enumerate whatever hardware has appeared in the FPGA. */
+
+API for programming an FPGA
+---------------------------
+
+* fpga_region_program_fpga() - Program an FPGA
+* fpga_image_info() - Specifies what FPGA image to program
+* fpga_image_info_alloc() - Allocate an FPGA image info struct
+* fpga_image_info_free() - Free an FPGA image info struct
+
+.. kernel-doc:: drivers/fpga/fpga-region.c
+ :functions: fpga_region_program_fpga
+
+FPGA Manager flags
+
+.. kernel-doc:: include/linux/fpga/fpga-mgr.h
+ :doc: FPGA Manager flags
+
+.. kernel-doc:: include/linux/fpga/fpga-mgr.h
+ :functions: fpga_image_info
+
+.. kernel-doc:: drivers/fpga/fpga-mgr.c
+ :functions: fpga_image_info_alloc
+
+.. kernel-doc:: drivers/fpga/fpga-mgr.c
+ :functions: fpga_image_info_free