[lkml]   [2011]   [Aug]   [10]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
Messages in this thread
    SubjectRe: [PATCH 5/8] staging: vme: add functions for bridge module refcounting
    On 10/08/11 10:15, Emilio G. Cota wrote:
    > On Wed, Aug 10, 2011 at 08:39:07 +0100, Martyn Welch wrote:
    >> And I think you need to go and do a grep of the code and find out where those
    >> functions are actually used, rather than blindly relying on the comment.
    > (snip)
    >> Go grep the code.
    > /me greps once again..
    > RapidIO: there are no rapidIO drivers upstream, only switches
    > and rionet, which does not manage RapidIO devices (it just sends
    > Ethernet packets on top of RapidIO's messaging). So obviously
    > there aren't any callers.

    Yes there are. In rio-driver.c for a start:

    * rio_device_probe - Tell if a RIO device structure has a matching RIO
    device id structure
    * @dev: the RIO device structure to match against
    * return 0 and set rio_dev->driver when drv claims rio_dev, else error
    static int rio_device_probe(struct device *dev)
    struct rio_driver *rdrv = to_rio_driver(dev->driver);
    struct rio_dev *rdev = to_rio_dev(dev);
    int error = -ENODEV;
    const struct rio_device_id *id;

    if (!rdev->driver && rdrv->probe) {
    if (!rdrv->id_table)
    return error;
    id = rio_match_device(rdrv->id_table, rdev);
    if (id)
    error = rdrv->probe(rdev, id);
    if (error >= 0) {
    rdev->driver = rdrv;
    error = 0;
    } else
    return error;

    Doing what Manohar suggested and I have agreed with.

    > PCI: pci_dev_get() referenced in 60 files. Another way of
    > explicitly incrementing the refcount of a pci device is with
    > pci_get_device(), which searches in the device list for a
    > particular one by its vendor/device ID. This function is
    > referenced in 127 files.

    Again, in pci-driver.c:

    static int pci_device_probe(struct device * dev)
    int error = 0;
    struct pci_driver *drv;
    struct pci_dev *pci_dev;

    drv = to_pci_driver(dev->driver);
    pci_dev = to_pci_dev(dev);
    error = __pci_device_probe(drv, pci_dev);
    if (error)

    return error;

    Again, doing as Manohar suggested.

    For those drivers using pci_get_device() - P313 of the Linux Device Drivers
    3rd Ed, under "Old-style PCI Probing". Not a mechanism currently supported for
    the VME bus.

    > USB: usb_get_dev() referenced in 75 files.

    I've already explained that I don't think the USB bus is good for comparison
    due to very real differences in bus topology and use.

    > There are also lots of direct calls to get_device() from .probe
    > methods of devices not tied to a particular bus.

    Which may therefore have nothing to do with a bus.

    > Guess that was enough grepping.

    It seems not quite.

    >> Suitable bug fixes are welcome.
    > I sent a fix (as part of an admittedly large patchset) in
    > Nov 2010[1], ie 9 months ago, you were sick at the time and
    > told me you'd have a look at the changes later[2], which
    > unfortunately never happened, even after pinging you off-list.

    Some of those patches were applied:;a=history;f=drivers/staging/vme;hb=HEAD

    The remaining patches completely changed the VME bus model. I said at the time
    I wasn't overly happy with the model you had put forward. Take this as my review:

    - I am not happy with the proposed alternative model.

    Sorry for not getting back to you sooner. I'm afraid my TODO list sometimes
    ends up acting as a stack rather than a FIFO.

    > Anyway let's forget that, Manohar's patches are what matters now.

    Will do.


    Martyn Welch (Principal Software Engineer) | Registered in England and
    GE Intelligent Platforms | Wales (3828642) at 100
    T +44(0)127322748 | Barbirolli Square, Manchester,
    E | M2 3AB VAT:GB 927559189

     \ /
      Last update: 2011-08-10 11:53    [W:0.026 / U:0.608 seconds]
    ©2003-2017 Jasper Spaans. hosted at Digital OceanAdvertise on this site