iwlwifi: document scan command

Document scan command.

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>
This commit is contained in:
Ben Cahill 2008-01-14 17:46:17 -08:00 committed by David S. Miller
parent 87e4f7dfe5
commit 3058f02137
2 changed files with 232 additions and 54 deletions

View file

@ -1020,6 +1020,10 @@ struct iwl3945_rate_scaling_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 iwl3945_bt_cmd {
u8 flags;
@ -1258,20 +1262,47 @@ struct iwl3945_ct_kill_config {
*
*****************************************************************************/
/**
* struct iwl3945_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 iwl3945_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 iwl3945_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 iwl3945_scan_cmd "flags" field */
struct iwl3945_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 iwl3945_ssid_ie - directed scan network information element
*
* Up to 4 of these may appear in REPLY_SCAN_CMD, selected by "type" field
* in struct iwl3945_scan_channel; each channel may select different ssids from
* among the 4 entries. SSID IEs get transmitted in reverse order of entry.
*/
struct iwl3945_ssid_ie {
u8 id;
u8 len;
@ -1285,40 +1316,98 @@ struct iwl3945_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, 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 iwl3945_scan_channel.
*/
struct iwl3945_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 */
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 reserved1;
__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;
__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 channel:
* 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 iwl3945_tx_cmd tx_cmd;
/* For directed active scans (set to all-0s otherwise) */
struct iwl3945_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 iwl3945_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. */

View file

@ -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;