delay_usecs has no effect with espi and spidev

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delay_usecs has no effect with espi and spidev

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derrictubbs
Contributor I

I'm using the spidev userspace driver on a t1040d4rdb platform with 4.1 kernel.  Changing .delay_usecs on the transfer structure is having no effect on the chip select and the chip select is going high simultaneously with the falling edge of the last clock pulse.  Has anyone had any luck setting the delay or does anyone know why this isn't working.  I looked in the espi driver code and it directly calls udelay with the value of .delay_usecs.  I have hard-coded a value in there now to see if ti changes anything but I can't get on the box to try the change at the moment (I work remote to the box and am having some unrelated networking issues at the moment).

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yipingwang
NXP TechSupport
NXP TechSupport

Hello Derric Tubbs,

Please refer to Documentation/spi/spidev_test.c in Linux Kernel source code, please refer to delay parameter specified through the command line.


Have a great day,
TIC

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