firewire: ohci: add module parameter to activate quirk fixes
authorStefan Richter <stefanr@s5r6.in-berlin.de>
Sun, 21 Feb 2010 16:58:29 +0000 (17:58 +0100)
committerStefan Richter <stefanr@s5r6.in-berlin.de>
Wed, 24 Feb 2010 19:36:55 +0000 (20:36 +0100)
This way, we can advise users of precompiled kernel packages to test
existing quirk fixes on chips which have not been listed yet, without
them having to build a kernel from source.

Note, to use this feature on a machine with more than one controller,
steps like these are necessary:
# lspci | grep 1394
# ls /sys/bus/pci/drivers/firewire_ohci/
# echo -n "0000:03:02.0" > /sys/bus/pci/drivers/firewire_ohci/unbind
# echo 2 > /sys/module/firewire_ohci/parameters/quirks
# echo -n "0000:03:02.0" > /sys/bus/pci/drivers/firewire_ohci/bind
# echo 0 > /sys/module/firewire_ohci/parameters/quirks

The parameter can also be used to switch off quirk flags that were
hardwired into firewire-ohci's quirks table.  Simply specify a non-zero
quirks value but without any known flags, e.g. 0x100.

Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
drivers/firewire/ohci.c

index 3dc2e8529a42c66621b33e2db75e494a2c20d6f0..9815137b7c7d8be249cf1d015a4b48aba830db76 100644 (file)
@@ -246,6 +246,15 @@ static const struct {
        {PCI_VENDOR_ID_APPLE,   PCI_DEVICE_ID_APPLE_UNI_N_FW, QUIRK_BE_HEADERS},
 };
 
+/* This overrides anything that was found in ohci_quirks[]. */
+static int param_quirks;
+module_param_named(quirks, param_quirks, int, 0644);
+MODULE_PARM_DESC(quirks, "Chip quirks (default = 0"
+       ", nonatomic cycle timer = "    __stringify(QUIRK_CYCLE_TIMER)
+       ", reset packet generation = "  __stringify(QUIRK_RESET_PACKET)
+       ", AR/selfID endianess = "      __stringify(QUIRK_BE_HEADERS)
+       ")");
+
 #ifdef CONFIG_FIREWIRE_OHCI_DEBUG
 
 #define OHCI_PARAM_DEBUG_AT_AR         1
@@ -2370,6 +2379,8 @@ static int __devinit pci_probe(struct pci_dev *dev,
                        ohci->quirks = ohci_quirks[i].flags;
                        break;
                }
+       if (param_quirks)
+               ohci->quirks = param_quirks;
 
        ar_context_init(&ohci->ar_request_ctx, ohci,
                        OHCI1394_AsReqRcvContextControlSet);