Re: [PATCH 2/3] pci: bcm43xx avoid pci_find_device

Michael Buesch
2006-06-05T20:36:15Z

On Monday 05 June 2006 22:18, Jiri Slaby wrote:
> bcm43xx avoid pci_find_device
>
> Change pci_find_device to safer pci_get_device with support for more
> devices.

I am wondering about the reference count.
>From docbook:

256 * pci_get_device - begin or continue searching for a PCI device by vendor/device id
257 * @vendor: PCI vendor id to match, or %PCI_ANY_ID to match all vendor ids
258 * @device: PCI device id to match, or %PCI_ANY_ID to match all device ids
259 * @from: Previous PCI device found in search, or %NULL for new search.
260 *
261 * Iterates through the list of known PCI devices. If a PCI device is
262 * found with a matching @vendor and @device, the reference count to the
^^^^^^^^^^^^^^^^^^^^^^
263 * device is incremented and a pointer to its device structure is returned.
^^^^^^^^^^^^^^^^^^^^^
264 * Otherwise, %NULL is returned. A new search is initiated by passing %NULL
265 * to the @from argument. Otherwise if @from is not %NULL, searches continue
266 * from next device on the global list. The reference count for @from is
267 * always decremented if it is not %NULL.

Who is going to decrement it, once the device is not used anymore.
"not used anymore" is ifconfig down in the case of bcm43xx.
You will call pci_get_device on each ifconfig up.

> Signed-off-by: Jiri Slaby <jirislaby@gmail.com>
>
> ---
> commit 4b73c16f5411d97360d5f26f292ffddeb670ff75
> tree 6e43c8bd02498eb1ceec6bdc64277fa8408da9e2
> parent d59f9ea8489749f59cd0c7333a4784cab964daa8
> author Jiri Slaby <ku@bellona.localdomain> Mon, 05 Jun 2006 22:01:03 +0159
> committer Jiri Slaby <ku@bellona.localdomain> Mon, 05 Jun 2006 22:01:03 +0159
>
> drivers/net/wireless/bcm43xx/bcm43xx_main.c | 21 ++++++++++++++++-----
> 1 files changed, 16 insertions(+), 5 deletions(-)
>
> diff --git a/drivers/net/wireless/bcm43xx/bcm43xx_main.c b/drivers/net/wireless/bcm43xx/bcm43xx_main.c
> index 22b8fa6..d1a9975 100644
> --- a/drivers/net/wireless/bcm43xx/bcm43xx_main.c
> +++ b/drivers/net/wireless/bcm43xx/bcm43xx_main.c
> @@ -2133,6 +2133,13 @@ out:
> return err;
> }
>
> +#ifdef CONFIG_BCM947XX
> +static struct pci_device_id bcm43xx_47xx_ids[] = {
> + { PCI_DEVICE(PCI_VENDOR_ID_BROADCOM, 0x4324) },
> + { 0 }
> +};
> +#endif
> +
> static int bcm43xx_initialize_irq(struct bcm43xx_private *bcm)
> {
> int res;
> @@ -2142,11 +2149,15 @@ static int bcm43xx_initialize_irq(struct
> bcm->irq = bcm->pci_dev->irq;
> #ifdef CONFIG_BCM947XX
> if (bcm->pci_dev->bus->number == 0) {
> - struct pci_dev *d = NULL;
> - /* FIXME: we will probably need more device IDs here... */
> - d = pci_find_device(PCI_VENDOR_ID_BROADCOM, 0x4324, NULL);
> - if (d != NULL) {
> - bcm->irq = d->irq;
> + struct pci_dev *d;
> + struct pci_device_id *id;
> + for (id = bcm43xx_47xx_ids; id->vendor; id++) {
> + d = pci_get_device(id->vendor, id->device, NULL);
> + if (d != NULL) {
> + bcm->irq = d->irq;
> + pci_dev_put(d);
> + break;
> + }
> }
> }
> #endif
>

--
Greetings Michael.