2011-05-20 10:53:37     Multiple SPI devices with SMP

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2011-05-20 10:53:37     Multiple SPI devices with SMP

Andre Berggren (SWEDEN)

Message: 100780   


We use a custom board based on ezkit bf561


We have enabled SMP and have two devices connected on the same SPI bus.


One device is a cusom device that we access several times per second. To this device we use the spidev driver.


The other  device is a SPI flash using the m25p80 driver.


I have tried adding spi_lock_bus() and spi_unlock_bus() calls to both drivers but if we access the flash while an application periodically using the other device the system hangs and then reboot.


Is this a ded end or will it be possible to atleast get it stable. I don't care about access tims at the moment.




2011-05-23 21:28:14     Re: Multiple SPI devices with SMP

Mike Frysinger (UNITED STATES)

Message: 100803   


what version of software are you using exactly ?  please run `make bugreport` and post the tarball as an attachment.


what SPI bus are you using ?  the on-chip Blackfin SPI bus ?


how are you hooking up these devices ?  over the SPI connector or the U-connector on the bottom of the board ?


the Blackfin SPI driver should work under SMP.  if it doesnt, it's a bug and we want to fix it.  but we'll need info in order to reproduce things.


using the spi_lock funcs should have no bearing at all here.