2006-05-31 10:37:38

by Jan Engelhardt

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Subject: parport and irq question

Hello,

standard parport probing gives:

# modprobe parport_pc
pnp: Device 00:0a activated.
parport: PnPBIOS parport detected.
parport0: PC-style at 0x378 (0x778), irq 7, dma 3
[PCSPP,TRISTATE,COMPAT,ECP,DMA]
ACPI: PCI Interrupt 0000:00:0c.0[A] -> GSI 16 (level, low) -> IRQ 185
PCI parallel port detected: 9710:9805, I/O at 0xc800(0xc400)
parport1: PC-style at 0xc800 (0xc400) [PCSPP,TRISTATE]
PCI parallel port detected: 9710:9805, I/O at 0xc000(0xbc00)
parport2: PC-style at 0xc000 (0xbc00) [PCSPP,TRISTATE]

Since I do not use parport0 but parport2 for regular work, I wanted to make
parport2 have the DMA channel, so I tried

# rmmod parport_pc
pnp: Device 00:0a disabled.

# modprobe parport_pc io=0x378,0xc800,0xc000 irq=100,101,7
parport 0x378 (WARNING): CTR: wrote 0x0c, read 0xff
parport 0x378 (WARNING): DATA: wrote 0xaa, read 0xff
parport 0x378: You gave this address, but there is probably no parallel
port there!
parport0: PC-style at 0x378, irq 100 [PCSPP,TRISTATE]
parport0: irq 100 in use, resorting to polled operation
parport1: PC-style at 0xc800, irq 101 [PCSPP,TRISTATE,EPP]
parport1: irq 101 in use, resorting to polled operation
parport2: PC-style at 0xc000 (0xc400), irq 7, dma 7
[PCSPP,TRISTATE,COMPAT,ECP,DMA]


Looks good so far, but what irq am I supposed to hand to the irq= parameter
for parport0 and parport1? Giving irq=-1,-1,7 is rejected. And what about
the "You gave this address, but there is probably no parallel port there?"
- there is one. It also appears when I try 0x778 instead of 0x378.



Jan Engelhardt
--


2006-05-31 16:55:47

by Brown, Len

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Subject: RE: parport and irq question

> what irq am I supposed to hand to the irq= parameter

does "auto" work any better?