iwlwifi: add comments to EEPROM stuff
Add comments to EEPROM stuff.
Signed-off-by: Ben Cahill <ben.m.cahill@intel.com>
Signed-off-by: Zhu Yi <yi.zhu@intel.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
diff --git a/drivers/net/wireless/iwlwifi/iwl-3945.c b/drivers/net/wireless/iwlwifi/iwl-3945.c
index 953a9be..51b9030 100644
--- a/drivers/net/wireless/iwlwifi/iwl-3945.c
+++ b/drivers/net/wireless/iwlwifi/iwl-3945.c
@@ -2202,6 +2202,7 @@
&rate_cmd);
}
+/* Called when initializing driver */
int iwl3945_hw_set_hw_setting(struct iwl3945_priv *priv)
{
memset((void *)&priv->hw_setting, 0,
@@ -2284,6 +2285,14 @@
{0}
};
+/*
+ * Clear the OWNER_MSK, to establish driver (instead of uCode running on
+ * embedded controller) as EEPROM reader; each read 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 some ownership mechanism. Here, the driver
+ * simply claims ownership, which should be safe when this function is called
+ * (i.e. before loading uCode!).
+ */
inline int iwl3945_eeprom_acquire_semaphore(struct iwl3945_priv *priv)
{
_iwl3945_clear_bit(priv, CSR_EEPROM_GP, CSR_EEPROM_GP_IF_OWNER_MSK);