iwlwifi: pcie: remove non-responsive device

If we fail to to grab NIC access because the device is not responding
(i.e. CSR_GP_CNTRL returns 0xFFFFFFFF), remove the device from the PCI
bus, to avoid any further damage, and to let the user space rescan.

In order to inform the userspace that a rescan is needed, we send a
kobject uevent with "INACCESSIBLE".

This functionality is disabled by default, but can be enabled via a
new module parameter called "remove_when_gone".  In the future we may
change this module parameter to include 3 modes instead: do nothing;
auto-rescan or; send uevent.

Signed-off-by: Luca Coelho <luciano.coelho@intel.com>
Signed-off-by: Rajat Jain <rajatja@google.com>

1 files changed, 6 insertions, 0 deletions

diff --git a/drivers/net/wireless/intel/iwlwifi/iwl-drv.c b/drivers/net/wireless/intel/iwlwifi/iwl-drv.c
index 4f451a6f20b9..c59ce4f8a5ed 100644
--- a/drivers/net/wireless/intel/iwlwifi/iwl-drv.c
+++ b/drivers/net/wireless/intel/iwlwifi/iwl-drv.c
@@ -1850,3 +1850,9 @@ MODULE_PARM_DESC(d0i3_timeout, "Timeout to D0i3 entry when idle (ms)");
 
 module_param_named(disable_11ac, iwlwifi_mod_params.disable_11ac, bool, 0444);
 MODULE_PARM_DESC(disable_11ac, "Disable VHT capabilities (default: false)");
+
+module_param_named(remove_when_gone,
+		   iwlwifi_mod_params.remove_when_gone, bool,
+		   0444);
+MODULE_PARM_DESC(remove_when_gone,
+		 "Remove dev from PCIe bus if it is deemed inaccessible (default: false)");