From 436bbd431d41e0fd3bfedb0312ab764b291ddf82 Mon Sep 17 00:00:00 2001 From: Christian Schmidt Date: Wed, 22 Aug 2007 14:01:19 -0700 Subject: [PATCH] Add blacklisting capability to serial_pci to avoid misdetection of serial ports The serial_pci driver tries to guess serial ports on unknown devices based on the PCI class (modem or serial). On certain softmodems (AC'97 modems) this can lead to the recognition of non-existing serial ports. This patch adds a blacklist of PCI IDs that are to be ignored by the driver. [akpm@linux-foundation.org: cleanups] Signed-off-by: Christian Schmidt Cc: Bjorn Helgaas Cc: Russell King Cc: Yinghai Lu Acked-by: Alan Cox Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- drivers/serial/8250_pci.c | 17 +++++++++++++++++ 1 file changed, 17 insertions(+) diff --git a/drivers/serial/8250_pci.c b/drivers/serial/8250_pci.c index fd76542c5977..e3140e5b16cc 100644 --- a/drivers/serial/8250_pci.c +++ b/drivers/serial/8250_pci.c @@ -1652,6 +1652,10 @@ static struct pciserial_board pci_boards[] __devinitdata = { }, }; +static const struct pci_device_id softmodem_blacklist[] = { + { PCI_VDEVICE ( AL, 0x5457 ), }, /* ALi Corporation M5457 AC'97 Modem */ +}; + /* * Given a complete unknown PCI device, try to use some heuristics to * guess what the configuration might be, based on the pitiful PCI @@ -1660,6 +1664,7 @@ static struct pciserial_board pci_boards[] __devinitdata = { static int __devinit serial_pci_guess_board(struct pci_dev *dev, struct pciserial_board *board) { + const struct pci_device_id *blacklist; int num_iomem, num_port, first_port = -1, i; /* @@ -1674,6 +1679,18 @@ serial_pci_guess_board(struct pci_dev *dev, struct pciserial_board *board) (dev->class & 0xff) > 6) return -ENODEV; + /* + * Do not access blacklisted devices that are known not to + * feature serial ports. + */ + for (blacklist = softmodem_blacklist; + blacklist < softmodem_blacklist + ARRAY_SIZE(softmodem_blacklist); + blacklist++) { + if (dev->vendor == blacklist->vendor && + dev->device == blacklist->device) + return -ENODEV; + } + num_iomem = num_port = 0; for (i = 0; i < PCI_NUM_BAR_RESOURCES; i++) { if (pci_resource_flags(dev, i) & IORESOURCE_IO) { -- 2.34.1