carl9170: improve site survey

The firmware keeps track of channel usage. This data can
be used by the automatic channel selection to find the
*best* channel.

Survey data from wlan22
	frequency:                      2412 MHz [in use]
	noise:                          -86 dBm
	channel active time:            3339608 ms
	channel busy time:              270982 ms
	channel transmit time:          121515 ms
Survey data from wlan22
	frequency:                      2417 MHz
	noise:                          -86 dBm
	channel active time:            70 ms
	channel busy time:              2 ms
	channel transmit time:          1 ms

Signed-off-by: Christian Lamparter <chunkeey@googlemail.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

1 files changed, 31 insertions, 0 deletions

diff --git a/drivers/net/wireless/ath/carl9170/cmd.c b/drivers/net/wireless/ath/carl9170/cmd.c
index cdfc94c371b4..9970bf8edc40 100644
--- a/drivers/net/wireless/ath/carl9170/cmd.c
+++ b/drivers/net/wireless/ath/carl9170/cmd.c
@@ -165,6 +165,37 @@ int carl9170_bcn_ctrl(struct ar9170 *ar, const unsigned int vif_id,
         return __carl9170_exec_cmd(ar, cmd, true);
 }
 
+int carl9170_collect_tally(struct ar9170 *ar)
+{
+        struct carl9170_tally_rsp tally;
+        struct survey_info *info;
+        unsigned int tick;
+        int err;
+
+        err = carl9170_exec_cmd(ar, CARL9170_CMD_TALLY, 0, NULL,
+                                sizeof(tally), (u8 *)&tally);
+        if (err)
+                return err;
+
+        tick = le32_to_cpu(tally.tick);
+        if (tick) {
+                ar->tally.active += le32_to_cpu(tally.active) / tick;
+                ar->tally.cca += le32_to_cpu(tally.cca) / tick;
+                ar->tally.tx_time += le32_to_cpu(tally.tx_time) / tick;
+                ar->tally.rx_total += le32_to_cpu(tally.rx_total);
+                ar->tally.rx_overrun += le32_to_cpu(tally.rx_overrun);
+
+                if (ar->channel) {
+                        info = &ar->survey[ar->channel->hw_value];
+
+                        info->channel_time = ar->tally.active / 1000;
+                        info->channel_time_busy = ar->tally.cca / 1000;
+                        info->channel_time_tx = ar->tally.tx_time / 1000;
+                }
+        }
+        return 0;
+}
+
 int carl9170_powersave(struct ar9170 *ar, const bool ps)
 {
         struct carl9170_cmd *cmd;