1 files changed, 41 insertions, 9 deletions

diff --git a/drivers/net/wireless/iwlwifi/iwl-eeprom.c b/drivers/net/wireless/iwlwifi/iwl-eeprom.c
index 402733638f50..c8397962632c 100644
--- a/drivers/net/wireless/iwlwifi/iwl-eeprom.c
+++ b/drivers/net/wireless/iwlwifi/iwl-eeprom.c
@@ -142,6 +142,45 @@ static const u8 iwl_eeprom_band_7[] = {       /* 5.2 ht40 channel */
  *
 ******************************************************************************/
 
+/*
+ * The device's EEPROM semaphore prevents conflicts between driver and uCode
+ * when accessing the EEPROM; each access is a series of pulses to/from the
+ * EEPROM chip, not a single event, so even reads could conflict if they
+ * weren't arbitrated by the semaphore.
+ */
+static int iwl_eeprom_acquire_semaphore(struct iwl_priv *priv)
+{
+        u16 count;
+        int ret;
+
+        for (count = 0; count < EEPROM_SEM_RETRY_LIMIT; count++) {
+                /* Request semaphore */
+                iwl_set_bit(priv, CSR_HW_IF_CONFIG_REG,
+                            CSR_HW_IF_CONFIG_REG_BIT_EEPROM_OWN_SEM);
+
+                /* See if we got it */
+                ret = iwl_poll_bit(priv, CSR_HW_IF_CONFIG_REG,
+                                CSR_HW_IF_CONFIG_REG_BIT_EEPROM_OWN_SEM,
+                                CSR_HW_IF_CONFIG_REG_BIT_EEPROM_OWN_SEM,
+                                EEPROM_SEM_TIMEOUT);
+                if (ret >= 0) {
+                        IWL_DEBUG_EEPROM(priv,
+                                "Acquired semaphore after %d tries.\n",
+                                count+1);
+                        return ret;
+                }
+        }
+
+        return ret;
+}
+
+static void iwl_eeprom_release_semaphore(struct iwl_priv *priv)
+{
+        iwl_clear_bit(priv, CSR_HW_IF_CONFIG_REG,
+                CSR_HW_IF_CONFIG_REG_BIT_EEPROM_OWN_SEM);
+
+}
+
 static int iwl_eeprom_verify_signature(struct iwl_priv *priv)
 {
         u32 gp = iwl_read32(priv, CSR_EEPROM_GP) & CSR_EEPROM_GP_VALID_MSK;
@@ -421,7 +460,7 @@ int iwl_eeprom_init(struct iwl_priv *priv, u32 hw_rev)
         }
 
         /* Make sure driver (instead of uCode) is allowed to read EEPROM */
-        ret = priv->cfg->ops->lib->eeprom_ops.acquire_semaphore(priv);
+        ret = iwl_eeprom_acquire_semaphore(priv);
         if (ret < 0) {
                 IWL_ERR(priv, "Failed to acquire EEPROM semaphore.\n");
                 ret = -ENOENT;
@@ -488,7 +527,7 @@ int iwl_eeprom_init(struct iwl_priv *priv, u32 hw_rev)
 
         ret = 0;
 done:
-        priv->cfg->ops->lib->eeprom_ops.release_semaphore(priv);
+        iwl_eeprom_release_semaphore(priv);
 
 err:
         if (ret)
@@ -711,13 +750,6 @@ int iwl_init_channel_map(struct iwl_priv *priv)
                                              flags & EEPROM_CHANNEL_RADAR))
                                        ? "" : "not ");
 
-                        /* Set the tx_power_user_lmt to the highest power
-                         * supported by any channel */
-                        if (eeprom_ch_info[ch].max_power_avg >
-                                                priv->tx_power_user_lmt)
-                                priv->tx_power_user_lmt =
-                                    eeprom_ch_info[ch].max_power_avg;
-
                         ch_info++;
                 }
         }