Messages in this thread | | | Date | Sun, 24 Jun 2007 13:44:06 -0600 | From | Robert Hancock <> | Subject | Re: character driver over PCI |
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ats wrote: > have a wireless network card over PCMCIA....i need to just access > the registers of this card and pass this register details to the user > application.Since i will not connect to the network at this stage i > preferred bypassing the network stack.Hence instead of a network > driver i went ahead writing a character driver. > > > I inserted the PCI module using insmod..That called PCI > probe....Inside PCI probe i registered by character driver by calling > register_chrdev().And i remapped the card memory by calling the > following sequence of functions. > > > pci_resource_start > request_mem_region > ioremap > > Then i created a device using mknod and called the open function of > the character driver.....Till here everything works fine.... > > > Once the device opened i made a readl call to read the mapped > memory..This fails..It gives me a segmentation fault.....If i call > readl in the probe function it works fine and reads the memory at that > location..However this call fails in open..What can be the reason... > > Have i proceeded the right way....Are there any additional things to > be set..Am working on linux 2.6 kernel > > Attached below is my prog
I don't see where it is trying to read anything in this code. The way in which you're doing that is likely the problem..
-- Robert Hancock Saskatoon, SK, Canada To email, remove "nospam" from hancockr@nospamshaw.ca Home Page: http://www.roberthancock.com/
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