Messages in this thread | | | Date | Wed, 12 Oct 2011 14:51:53 +0100 | From | Alan Cox <> | Subject | Re: Using serial driver 16550A in poll mode without interrupt connected |
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> Driver is probed with no IRQ (NO_IRQ = -1 on Microblaze) > 83e00000.serial: ttyS0 at MMIO 0x83e01003 (irq = -1) is a 16550A
Zero means no IRQ. NO_IRQ is a legacy internal thing for the old IDE code so not something other code should be using. Setting the IRQ to -1 is bogus and will confuse the rest of the kernel.
> Is it possible to use serial driver without IRQ - or blocking IRQ, etc.?
Within limits - it kills your power management and data rates because of the continual polling.
Alan
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