ath5k: Fix eeprom checksum check for custom sized eeproms (Closes: #563136)

svn path=/dists/trunk/linux-2.6/; revision=14898

2 files changed, 105 insertions, 0 deletions

diff --git a/debian/patches/bugfix/all/ath5k-Fix-eeprom-checksum-check-for-custom-sized-eeproms.patch b/debian/patches/bugfix/all/ath5k-Fix-eeprom-checksum-check-for-custom-sized-eeproms.patch
new file mode 100644
index 000000000000..7965f096f8a3
--- /dev/null
+++ b/debian/patches/bugfix/all/ath5k-Fix-eeprom-checksum-check-for-custom-sized-eeproms.patch
@@ -0,0 +1,104 @@
+From 608ad4393323f00eab79828bdfda3ff1d520532e Mon Sep 17 00:00:00 2001
+From: Luis R. Rodriguez <lrodriguez@atheros.com>
+Date: Mon, 28 Dec 2009 15:40:42 -0800
+Subject: [PATCH] ath5k: Fix eeprom checksum check for custom sized eeproms
+
+Commit 8bf3d79bc401ca417ccf9fc076d3295d1a71dbf5 enabled EEPROM
+checksum checks to avoid bogus bug reports but failed to address
+updating the code to consider devices with custom EEPROM sizes.
+Devices with custom sized EEPROMs have the upper limit size stuffed
+in the EEPROM. Use this as the upper limit instead of the static
+default size. In case of a checksum error also provide back the
+max size and whether or not this was the default size or a custom
+one. If the EEPROM is busted we add a failsafe check to ensure
+we don't loop forever or try to read bogus areas of hardware.
+
+For details refer to the bugzilla entry:
+
+http://bugzilla.kernel.org/show_bug.cgi?id=14874
+
+Cc: stable@kernel.org
+Cc: David Quan <david.quan@atheros.com>
+Reported-by: Joshua Covington <joshuacov@googlemail.com>
+Signed-off-by: Luis R. Rodriguez <lrodriguez@atheros.com>
+---
+ drivers/net/wireless/ath/ath5k/eeprom.c |   32 ++++++++++++++++++++++++++++--
+ drivers/net/wireless/ath/ath5k/eeprom.h |    8 +++++++
+ 2 files changed, 37 insertions(+), 3 deletions(-)
+
+diff --git a/drivers/net/wireless/ath/ath5k/eeprom.c b/drivers/net/wireless/ath/ath5k/eeprom.c
+index 5d1c867..6a3f4da 100644
+--- a/drivers/net/wireless/ath/ath5k/eeprom.c
++++ b/drivers/net/wireless/ath/ath5k/eeprom.c
+@@ -97,7 +97,7 @@ ath5k_eeprom_init_header(struct ath5k_hw *ah)
+ 	struct ath5k_eeprom_info *ee = &ah->ah_capabilities.cap_eeprom;
+ 	int ret;
+ 	u16 val;
+-	u32 cksum, offset;
++	u32 cksum, offset, eep_max = AR5K_EEPROM_INFO_MAX;
+ 
+ 	/*
+ 	 * Read values from EEPROM and store them in the capability structure
+@@ -116,12 +116,38 @@ ath5k_eeprom_init_header(struct ath5k_hw *ah)
+ 	 * Validate the checksum of the EEPROM date. There are some
+ 	 * devices with invalid EEPROMs.
+ 	 */
+-	for (cksum = 0, offset = 0; offset < AR5K_EEPROM_INFO_MAX; offset++) {
++	AR5K_EEPROM_READ(AR5K_EEPROM_SIZE_UPPER, val);
++	if (val) {
++		eep_max = (val & AR5K_EEPROM_SIZE_UPPER_MASK) <<
++			   AR5K_EEPROM_SIZE_ENDLOC_SHIFT;
++		AR5K_EEPROM_READ(AR5K_EEPROM_SIZE_LOWER, val);
++		eep_max = (eep_max | val) - AR5K_EEPROM_INFO_BASE;
++
++		/*
++		 * Fail safe check to prevent stupid loops due
++		 * to busted EEPROMs. XXX: This value is likely too
++		 * big still, waiting on a better value.
++		 */
++		if (eep_max > (3 * AR5K_EEPROM_INFO_MAX)) {
++			ATH5K_ERR(ah->ah_sc, "Invalid max custom EEPROM size: "
++				  "%d (0x%04x) max expected: %d (0x%04x)\n",
++				  eep_max, eep_max,
++				  3 * AR5K_EEPROM_INFO_MAX,
++				  3 * AR5K_EEPROM_INFO_MAX);
++			return -EIO;
++		}
++	}
++
++	for (cksum = 0, offset = 0; offset < eep_max; offset++) {
+ 		AR5K_EEPROM_READ(AR5K_EEPROM_INFO(offset), val);
+ 		cksum ^= val;
+ 	}
+ 	if (cksum != AR5K_EEPROM_INFO_CKSUM) {
+-		ATH5K_ERR(ah->ah_sc, "Invalid EEPROM checksum 0x%04x\n", cksum);
++		ATH5K_ERR(ah->ah_sc, "Invalid EEPROM "
++			  "checksum: 0x%04x eep_max: 0x%04x (%s)\n",
++			  cksum, eep_max,
++			  eep_max == AR5K_EEPROM_INFO_MAX ?
++				"default size" : "custom size");
+ 		return -EIO;
+ 	}
+ 
+diff --git a/drivers/net/wireless/ath/ath5k/eeprom.h b/drivers/net/wireless/ath/ath5k/eeprom.h
+index 0123f35..473a483 100644
+--- a/drivers/net/wireless/ath/ath5k/eeprom.h
++++ b/drivers/net/wireless/ath/ath5k/eeprom.h
+@@ -37,6 +37,14 @@
+ #define AR5K_EEPROM_RFKILL_POLARITY_S	1
+ 
+ #define AR5K_EEPROM_REG_DOMAIN		0x00bf	/* EEPROM regdom */
++
++/* FLASH(EEPROM) Defines for AR531X chips */
++#define AR5K_EEPROM_SIZE_LOWER		0x1b /* size info -- lower */
++#define AR5K_EEPROM_SIZE_UPPER		0x1c /* size info -- upper */
++#define AR5K_EEPROM_SIZE_UPPER_MASK	0xfff0
++#define AR5K_EEPROM_SIZE_UPPER_SHIFT	4
++#define AR5K_EEPROM_SIZE_ENDLOC_SHIFT	12
++
+ #define AR5K_EEPROM_CHECKSUM		0x00c0	/* EEPROM checksum */
+ #define AR5K_EEPROM_INFO_BASE		0x00c0	/* EEPROM header */
+ #define AR5K_EEPROM_INFO_MAX		(0x400 - AR5K_EEPROM_INFO_BASE)
+-- 
+1.6.3.3
+
diff --git a/debian/patches/series/5 b/debian/patches/series/5
index 068dbbb62e3a..f3637f88d9af 100644
--- a/debian/patches/series/5
+++ b/debian/patches/series/5
@@ -6,3 +6,4 @@
 + bugfix/all/sfc-QT2025C-Work-around-PHY-firmware-initialisation.patch
 + bugfix/all/sfc-QT2025C-Add-error-message-for-suspected-bad-SFP-cable.patch
 + bugfix/all/sfc-Disable-TX-descriptor-prefetch-watchdog.patch
++ bugfix/all/ath5k-Fix-eeprom-checksum-check-for-custom-sized-eeproms.patch