diff options
Diffstat (limited to 'drivers/net/wireless/iwlwifi/iwl-4965-commands.h')
| -rw-r--r-- | drivers/net/wireless/iwlwifi/iwl-4965-commands.h | 147 |
1 files changed, 118 insertions, 29 deletions
diff --git a/drivers/net/wireless/iwlwifi/iwl-4965-commands.h b/drivers/net/wireless/iwlwifi/iwl-4965-commands.h index 7988c752a66..9237f8b3bb8 100644 --- a/drivers/net/wireless/iwlwifi/iwl-4965-commands.h +++ b/drivers/net/wireless/iwlwifi/iwl-4965-commands.h @@ -1615,6 +1615,10 @@ struct iwl4965_link_quality_cmd { /* * REPLY_BT_CONFIG = 0x9b (command, has simple generic response) + * + * 3945 and 4965 support hardware handshake with Bluetooth device on + * same platform. Bluetooth device alerts wireless device when it will Tx; + * wireless device can delay or kill its own Tx to accomodate. */ struct iwl4965_bt_cmd { u8 flags; @@ -1857,20 +1861,47 @@ struct iwl4965_ct_kill_config { * *****************************************************************************/ +/** + * struct iwl4965_scan_channel - entry in REPLY_SCAN_CMD channel table + * + * One for each channel in the scan list. + * Each channel can independently select: + * 1) SSID for directed active scans + * 2) Txpower setting (for rate specified within Tx command) + * 3) How long to stay on-channel (behavior may be modified by quiet_time, + * quiet_plcp_th, good_CRC_th) + * + * To avoid uCode errors, make sure the following are true (see comments + * under struct iwl4965_scan_cmd about max_out_time and quiet_time): + * 1) If using passive_dwell (i.e. passive_dwell != 0): + * active_dwell <= passive_dwell (< max_out_time if max_out_time != 0) + * 2) quiet_time <= active_dwell + * 3) If restricting off-channel time (i.e. max_out_time !=0): + * passive_dwell < max_out_time + * active_dwell < max_out_time + */ struct iwl4965_scan_channel { - /* type is defined as: - * 0:0 active (0 - passive) - * 1:4 SSID direct - * If 1 is set then corresponding SSID IE is transmitted in probe + /* + * type is defined as: + * 0:0 1 = active, 0 = passive + * 1:4 SSID direct bit map; if a bit is set, then corresponding + * SSID IE is transmitted in probe request. * 5:7 reserved */ u8 type; - u8 channel; + u8 channel; /* band is selected by iwl4965_scan_cmd "flags" field */ struct iwl4965_tx_power tpc; - __le16 active_dwell; - __le16 passive_dwell; + __le16 active_dwell; /* in 1024-uSec TU (time units), typ 5-50 */ + __le16 passive_dwell; /* in 1024-uSec TU (time units), typ 20-500 */ } __attribute__ ((packed)); +/** + * struct iwl4965_ssid_ie - directed scan network information element + * + * Up to 4 of these may appear in REPLY_SCAN_CMD, selected by "type" field + * in struct iwl4965_scan_channel; each channel may select different ssids from + * among the 4 entries. SSID IEs get transmitted in reverse order of entry. + */ struct iwl4965_ssid_ie { u8 id; u8 len; @@ -1884,40 +1915,98 @@ struct iwl4965_ssid_ie { /* * REPLY_SCAN_CMD = 0x80 (command) + * + * The hardware scan command is very powerful; the driver can set it up to + * maintain (relatively) normal network traffic while doing a scan in the + * background. The max_out_time and suspend_time control the ratio of how + * long the device stays on an associated network channel ("service channel") + * vs. how long it's away from the service channel, i.e. tuned to other channels + * for scanning. + * + * max_out_time is the max time off-channel (in usec), and suspend_time + * is how long (in "extended beacon" format) that the scan is "suspended" + * after returning to the service channel. That is, suspend_time is the + * time that we stay on the service channel, doing normal work, between + * scan segments. The driver may set these parameters differently to support + * scanning when associated vs. not associated, and light vs. heavy traffic + * loads when associated. + * + * After receiving this command, the device's scan engine does the following; + * + * 1) Sends SCAN_START notification to driver + * 2) Checks to see if it has time to do scan for one channel + * 3) Sends NULL packet, with power-save (PS) bit set to 1, + * to tell AP that we're going off-channel + * 4) Tunes to first channel in scan list, does active or passive scan + * 5) Sends SCAN_RESULT notification to driver + * 6) Checks to see if it has time to do scan on *next* channel in list + * 7) Repeats 4-6 until it no longer has time to scan the next channel + * before max_out_time expires + * 8) Returns to service channel + * 9) Sends NULL packet with PS=0 to tell AP that we're back + * 10) Stays on service channel until suspend_time expires + * 11) Repeats entire process 2-10 until list is complete + * 12) Sends SCAN_COMPLETE notification + * + * For fast, efficient scans, the scan command also has support for staying on + * a channel for just a short time, if doing active scanning and getting no + * responses to the transmitted probe request. This time is controlled by + * quiet_time, and the number of received packets below which a channel is + * considered "quiet" is controlled by quiet_plcp_threshold. + * + * For active scanning on channels that have regulatory restrictions against + * blindly transmitting, the scan can listen before transmitting, to make sure + * that there is already legitimate activity on the channel. If enough + * packets are cleanly received on the channel (controlled by good_CRC_th, + * typical value 1), the scan engine starts transmitting probe requests. + * + * Driver must use separate scan commands for 2.4 vs. 5 GHz bands. + * + * To avoid uCode errors, see timing restrictions described under + * struct iwl4965_scan_channel. */ struct iwl4965_scan_cmd { __le16 len; u8 reserved0; - u8 channel_count; - __le16 quiet_time; /* dwell only this long on quiet chnl - * (active scan) */ - __le16 quiet_plcp_th; /* quiet chnl is < this # pkts (typ. 1) */ - __le16 good_CRC_th; /* passive -> active promotion threshold */ - __le16 rx_chain; - __le32 max_out_time; /* max usec to be out of associated (service) - * chnl */ - __le32 suspend_time; /* pause scan this long when returning to svc - * chnl. - * 3945 -- 31:24 # beacons, 19:0 additional usec, - * 4965 -- 31:22 # beacons, 21:0 additional usec. - */ - __le32 flags; - __le32 filter_flags; - + u8 channel_count; /* # channels in channel list */ + __le16 quiet_time; /* dwell only this # millisecs on quiet channel + * (only for active scan) */ + __le16 quiet_plcp_th; /* quiet chnl is < this # pkts (typ. 1) */ + __le16 good_CRC_th; /* passive -> active promotion threshold */ + __le16 rx_chain; /* RXON_RX_CHAIN_* */ + __le32 max_out_time; /* max usec to be away from associated (service) + * channel */ + __le32 suspend_time; /* pause scan this long (in "extended beacon + * format") when returning to service chnl: + * 3945; 31:24 # beacons, 19:0 additional usec, + * 4965; 31:22 # beacons, 21:0 additional usec. + */ + __le32 flags; /* RXON_FLG_* */ + __le32 filter_flags; /* RXON_FILTER_* */ + + /* For active scans (set to all-0s for passive scans). + * Does not include payload. Must specify Tx rate; no rate scaling. */ struct iwl4965_tx_cmd tx_cmd; + + /* For directed active scans (set to all-0s otherwise) */ struct iwl4965_ssid_ie direct_scan[PROBE_OPTION_MAX]; - u8 data[0]; /* - * The channels start after the probe request payload and are of type: + * Probe request frame, followed by channel list. + * + * Size of probe request frame is specified by byte count in tx_cmd. + * Channel list follows immediately after probe request frame. + * Number of channels in list is specified by channel_count. + * Each channel in list is of type: * * struct iwl4965_scan_channel channels[0]; * * NOTE: Only one band of channels can be scanned per pass. You - * can not mix 2.4GHz channels and 5.2GHz channels and must - * request a scan multiple times (not concurrently) - * + * must not mix 2.4GHz channels and 5.2GHz channels, and you must wait + * for one scan to complete (i.e. receive SCAN_COMPLETE_NOTIFICATION) + * before requesting another scan. */ + u8 data[0]; } __attribute__ ((packed)); /* Can abort will notify by complete notification with abort status. */ @@ -2087,7 +2176,7 @@ struct statistics_rx_non_phy { __le32 interference_data_flag; /* flag for interference data * availability. 1 when data is * available. */ - __le32 channel_load; /* counts RX Enable time */ + __le32 channel_load; /* counts RX Enable time in uSec */ __le32 dsp_false_alarms; /* DSP false alarm (both OFDM * and CCK) counter */ __le32 beacon_rssi_a; |