The VSP1 library driver offers support for programming the VSP using display lists. Display lists are created in a pool and users can get them and use them to program the VSP. Once done the display list shall be returned to the display list pool. The correct management of the display list pool is left to the user of the helpers, and it's helpful to add a few checks to detect invalid usage patterns, such as a double release or a non-returned display list. Add two counters to detect double releases of a display list, and a counter to the display list to make sure that once it is reset all the display lists have been returned. Tested with vsp-tests 170 tests: 165 passed, 0 failed, 5 skipped However I got a (hopefully unrelated) warning: [ 795.547528] [<000000007d841fd6>] vsp1_irq_handler [ 795.552448] Disabling IRQ #43 [ 795.653324] vsp1 fea20000.vsp: Underrun occurred at WPF1 (total underruns 1) Signed-off-by: Jacopo Mondi <jacopo.mondi+renesas@xxxxxxxxxxxxxxxx> --- Changes in v2: - Use a boolean to keep track of DL state - minor changes - Link to v1: https://lore.kernel.org/r/20250529-vsp1_dl_list_count-v1-0-40c6d0e20592@xxxxxxxxxxxxxxxx --- Jacopo Mondi (2): media: vsp1: vsp1_dl: Detect double list release media: vsp1: vsp1_dl: Count display lists drivers/media/platform/renesas/vsp1/vsp1_dl.c | 19 +++++++++++++++++++ 1 file changed, 19 insertions(+) --- base-commit: 4d2c3d70799f5eb210003613766bbd113bbebc1a change-id: 20250529-vsp1_dl_list_count-156d27a2d5b1 Best regards, -- Jacopo Mondi <jacopo.mondi+renesas@xxxxxxxxxxxxxxxx>