iwlwifi: validate enhanced tx power entry
Validate enhanced tx power entry read from EEPROM before applying the
tx power value. Different versions of EEPROM might contain different size
of table; always a good idea to make sure the entry is valid before
applying to the targeted channel.
Signed-off-by: Wey-Yi Guy <wey-yi.w.guy@intel.com>
Signed-off-by: Reinette Chatre <reinette.chatre@intel.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
diff --git a/drivers/net/wireless/iwlwifi/iwl-eeprom.c b/drivers/net/wireless/iwlwifi/iwl-eeprom.c
index 8a0709e..143728c 100644
--- a/drivers/net/wireless/iwlwifi/iwl-eeprom.c
+++ b/drivers/net/wireless/iwlwifi/iwl-eeprom.c
@@ -913,6 +913,16 @@
enhanced_txpower = (struct iwl_eeprom_enhanced_txpwr *)
iwl_eeprom_query_addr(priv, offset);
+ /*
+ * check for valid entry -
+ * different version of EEPROM might contain different set
+ * of enhanced tx power table
+ * always check for valid entry before process
+ * the information
+ */
+ if (!enhanced_txpower->common || enhanced_txpower->reserved)
+ continue;
+
for (element = 0; element < eeprom_section_count; element++) {
if (enhinfo[section].is_common)
max_txpower_avg =
diff --git a/drivers/net/wireless/iwlwifi/iwl-eeprom.h b/drivers/net/wireless/iwlwifi/iwl-eeprom.h
index 5ba5a4e..5cd2b66 100644
--- a/drivers/net/wireless/iwlwifi/iwl-eeprom.h
+++ b/drivers/net/wireless/iwlwifi/iwl-eeprom.h
@@ -127,19 +127,21 @@
* Enhanced regulatory tx power portion of eeprom image can be broken down
* into individual structures; each one is 8 bytes in size and contain the
* following information
+ * @common: (desc + channel) not used by driver, should _NOT_ be "zero"
* @chain_a_max_pwr: chain a max power in 1/2 dBm
* @chain_b_max_pwr: chain b max power in 1/2 dBm
* @chain_c_max_pwr: chain c max power in 1/2 dBm
+ * @reserved: not used, should be "zero"
* @mimo2_max_pwr: mimo2 max power in 1/2 dBm
* @mimo3_max_pwr: mimo3 max power in 1/2 dBm
*
*/
struct iwl_eeprom_enhanced_txpwr {
- u16 reserved;
+ u16 common;
s8 chain_a_max;
s8 chain_b_max;
s8 chain_c_max;
- s8 reserved1;
+ s8 reserved;
s8 mimo2_max;
s8 mimo3_max;
} __attribute__ ((packed));