On Wed, Feb 24, 2016 at 07:09:57PM +0800, Huang, Tao wrote: Please don't top post, reply in line with needed context. This allows readers to readily follow the flow of conversation and understand what you are talking about and also helps ensure that everything in the discussion is being addressed. > Another way to solve this bug is add runtime PM support while spi setup. > Some other chips may have some problem, for example mt65xx and orion, > which access hardware register too. No, this is telling you you're doing something wrong - setup() might be called while another transfer is in progress so you shouldn't be changing the hardware setup (see Documentation/spi/spi-summary). This means that you normally shouldn't be writing to registers there. Moving this to prepare_message() instead is probably what you want. -------------- next part -------------- A non-text attachment was scrubbed... Name: signature.asc Type: application/pgp-signature Size: 473 bytes Desc: not available URL: <http://lists.infradead.org/pipermail/linux-rockchip/attachments/20160226/8daa5a5b/attachment.sig>