diff options
| author | Ben Cahill <ben.m.cahill@intel.com> | 2007-11-29 11:09:45 +0800 |
|---|---|---|
| committer | David S. Miller <davem@davemloft.net> | 2008-01-28 15:05:15 -0800 |
| commit | 796083cb1d45d52d40ae2c933afcfc56d91ef427 (patch) | |
| tree | c5dc4a5e7d6437a2a073ee15996f3b1e3ff7e657 /drivers/net/wireless/iwlwifi/iwl-4965.c | |
| parent | 7762635547ad31ecb045e7073989e76ae13e6c54 (diff) | |
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>
Diffstat (limited to 'drivers/net/wireless/iwlwifi/iwl-4965.c')
| -rw-r--r-- | drivers/net/wireless/iwlwifi/iwl-4965.c | 9 |
1 files changed, 9 insertions, 0 deletions
diff --git a/drivers/net/wireless/iwlwifi/iwl-4965.c b/drivers/net/wireless/iwlwifi/iwl-4965.c index 5dee8e512c7..7d95de9d034 100644 --- a/drivers/net/wireless/iwlwifi/iwl-4965.c +++ b/drivers/net/wireless/iwlwifi/iwl-4965.c @@ -4687,14 +4687,23 @@ struct pci_device_id iwl4965_hw_card_ids[] = { {0} }; +/* + * 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. + */ int iwl4965_eeprom_acquire_semaphore(struct iwl4965_priv *priv) { u16 count; int rc; for (count = 0; count < EEPROM_SEM_RETRY_LIMIT; count++) { + /* Request semaphore */ iwl4965_set_bit(priv, CSR_HW_IF_CONFIG_REG, CSR_HW_IF_CONFIG_REG_BIT_EEPROM_OWN_SEM); + + /* See if we got it */ rc = iwl4965_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, |