Messages in this thread | | | Date | Wed, 14 Sep 2005 16:28:49 +0400 | From | Manu Abraham <> | Subject | Re: PCI driver |
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Jiri Slaby wrote:
> Manu Abraham napsal(a): > >> Jiri Slaby wrote: >> >>> Manu Abraham napsal(a): >>> >>>> Jiri Slaby wrote: >>>> >>>>> Manu Abraham napsal(a): >>>>> >>>>>> Now that i have been trying to implement the driver using the new >>>>>> PCI API, i feel a bit lost at the different changes gone into the >>>>>> PCI API. So if someone could give me a brief idea how a minimal >>>>>> PCI probe routine should consist of, that would be quite helpful. >>>>> >>>>> >>>>> >>>>> >>>>> >>>>> >>>>> Maybe, you want to read http://lwn.net/Kernel/LDD3/, chapter 12, >>>>> pages 311+. >>>>> >>>> >>>> I have been updating myself from LDD2 to LDD3. What i was wondering >>>> was in what order should i be calling the functions. >>> >>> >>> >>> >>> You won't call anything, kernel does. You only register driver. >>> struct pcitbl {venids, devids} >>> >>> struct driver ... = {probe=a, remove=b, tbl=pcitbl}; >>> a() { if device from pcitbl is in the system (or has been added >>> before some little time) this function is called} >>> b() {if the device was removed from system: modules and hotplug: >>> never called; modules: so if modules unload; if both: if the device >>> was removed on the fly, or module unload} >>> >>> module_init() { register_driver(driver)} >>> module_exit() { unregister_driver(driver); } >>> >> >> I was wondering whether pci_enable_device() should come first or >> pci_dev_put() in the probe routine. > > pci_dev_put? No, it counts down reference count, so you would loose > the structure. You do NOT do pci_dev_put anymore with pci probing (but > some very very specific cases).
Oh, i thought after a pci_dev_get() one does a pci_dev_put() I wrote something like this, i was now confused with what to do with pci_get_drvdata() and pci_set_drvdata() I am not very sure whether i am doing it right in the first place, since my mapped memory seems to be wrong, but first i have to clear up about pci_get/set_drvdata().
Manu
static int mantis_pci_probe(*struct* pci_dev *pdev, const *struct* pci_device_id *mantis_pci_table) { *struct* mantis_pci *mantis; u8 revision, latency;
pdev = pci_get_device(PCI_VENDOR_ID_MANTIS, PCI_DEVICE_ID_MANTIS_R11, NULL); *if* (pdev) { dprintk(verbose, MANTIS_DEBUG, 1, "Found a mantis chip"); *if* ((mantis = (*struct* mantis_pci *) kmalloc(*sizeof* (*struct* mantis_pci), GFP_KERNEL)) == NULL) { dprintk(verbose, MANTIS_ERROR, 1, "Out of memory"); *return* -ENOMEM; } *if* (pci_enable_device(pdev) < 0) { dprintk(verbose, MANTIS_ERROR, 1, "Could not enable device"); kfree(mantis); *return* -ENODEV; } mantis->pdev = pdev; mantis->mantis_addr = pci_resource_start(pdev, 0); *if* (!request_mem_region(pci_resource_start(pdev, 0), pci_resource_len(pdev, 0), DRIVER_NAME)) { kfree(mantis); *return* -EBUSY; } pci_read_config_byte(mantis->pdev, PCI_CLASS_REVISION, &revision); pci_read_config_byte(mantis->pdev, PCI_LATENCY_TIMER, &latency); mantis->mantis_mmio = ioremap(mantis->mantis_addr, 0x1000); mmwrite(0, MANTIS_INT_STAT); //* Clear interrupts *// *if* (request_irq(mantis->pdev->irq, (void *) mantis_pci_irq, SA_SHIRQ | SA_INTERRUPT, DRIVER_NAME, (void *) mantis) < 0) { dprintk(verbose, MANTIS_ERROR, 1, "Mantis IRQ registration failed"); release_mem_region(pci_resource_start(mantis->pdev, 0), pci_resource_len(mantis->pdev, 0)); pci_disable_device(pdev); kfree(mantis); } pci_dev_put(pdev);
}
*return* 0; }
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