From 569637796f56aba48defaee0736ecfd5f94487be Mon Sep 17 00:00:00 2001
From: proski <proski@0192ed92-7a03-0410-a25b-9323aeb14dbd>
Date: Wed, 30 Jul 2008 21:33:40 +0000
Subject: [PATCH] Protect against probing AR2425 if HAL doesn't support it

AR2424 and AR2425 share the same PCI ID.  Probing AR2425 with HAL that
doesn't support it is problematic.  It causes an unhandled NMI and puts
the device to a non-functional state.  After that, even HAL that
supports AR2425 won't be able to use the device until the system is
rebooted.

Reject AR2425 devices if HAL doesn't positively indicate support for
them.


git-svn-id: http://madwifi-project.org/svn/madwifi/trunk@3825 0192ed92-7a03-0410-a25b-9323aeb14dbd
---
 ath/if_ath_pci.c | 19 +++++++++++++++++++
 1 file changed, 19 insertions(+)

diff --git a/ath/if_ath_pci.c b/ath/if_ath_pci.c
index f9ccd1e..2e77378 100644
--- a/ath/if_ath_pci.c
+++ b/ath/if_ath_pci.c
@@ -190,6 +190,25 @@ ath_pci_probe(struct pci_dev *pdev, const struct pci_device_id *id)
 		goto bad1;
 	}
 
+/*
+ * Reject new MAC revisions if HAL doesn't support AR2425.  Ideally, it could
+ * be done in the PCI ID table, but AR2424 and AR2425 share the same vendor ID
+ * 168c:001c.
+ */
+#ifndef AH_SUPPORT_2425
+#define AR5K_SREV		0x4020	/* MAC revision */
+#define AR5K_SREV_CUTOFF	0xE0	/* Cutoff revision */
+	{
+		u_int32_t mac_rev = readl(mem + AR5K_SREV);
+		if (mac_rev > AR5K_SREV_CUTOFF)
+		{
+			printk(KERN_ERR "%s: HAL doesn't support MAC revision "
+			       "0x%02x\n", dev_info, mac_rev);
+			goto bad2;
+		}
+	}
+#endif
+
 	dev = alloc_netdev(sizeof(struct ath_pci_softc), "wifi%d", ether_setup);
 	if (dev == NULL) {
 		printk(KERN_ERR "%s: no memory for device state\n", dev_info);