Hi Rahul, thanks for the feedback, I will add it to the driver. > My personal recommendation is to just have a single DMA buffer allocated > for the mcp2200 instance rather than having to call the allocator and > release the memory per command. I added an 16-byte Array hid_report to the mcp2000 struct. When I need the report, I do the following: struct mcp_set_clear_outputs *cmd; mutex_lock(&mcp->lock); cmd = (struct mcp_set_clear_outputs *) mcp->hid_report Do you think this is a valid implementation or do I really have to add a pointer to the mcp2200 struct instead of the 16 byte array and allocate another 16 byte for it in the probe function? > The reason you run into this is likely because of the action added to > devm conflicting with hid_device_remove.... > > I recommend not depending on devm for teardown rather than making a stub > remove function to work around the issue. I am not sure, if I have understand this correctly, but basically I already have a stub remove function (which is empty). First the remove function gets called, then the unregister function and everything is cleaned up correctly. Did I get this right or do you have any other recommendation for me? So, do I need any adaptions, or can we go with the empty remove function? Best regards, Johannes
