[PATCH 04/31] staging: wfx: wait for SCAN_CMPL after a SCAN_STOP

From: Jerome Pouiller
Date: Fri Sep 10 2021 - 12:06:01 EST


From: Jérôme Pouiller <jerome.pouiller@xxxxxxxxxx>

When the device has finished a scan request, it send a scan complete
("SCAN_COMPL") indication. It is also possible to abort a scan request
with a "SCAN_STOP" message. A SCAN_COMPL is also send in this case.

The driver limits the delay to make a scan request. A timeout happens
almost never but is theoretically possible. Currently, if it happens
the driver does not wait for the SCAN_COMPL. Then, when the driver
starts the next scan request, the device may return -EBUSY (scan
requests often occur back-to-back).

This patch give a chance to the device to send a SCAN_COMPL after a scan
timeout.

Signed-off-by: Jérôme Pouiller <jerome.pouiller@xxxxxxxxxx>
---
drivers/staging/wfx/scan.c | 24 ++++++++++++++++--------
1 file changed, 16 insertions(+), 8 deletions(-)

diff --git a/drivers/staging/wfx/scan.c b/drivers/staging/wfx/scan.c
index fb47c7cddf2f..1e03b130049b 100644
--- a/drivers/staging/wfx/scan.c
+++ b/drivers/staging/wfx/scan.c
@@ -58,23 +58,31 @@ static int send_scan_req(struct wfx_vif *wvif,
reinit_completion(&wvif->scan_complete);
ret = hif_scan(wvif, req, start_idx, i - start_idx, &timeout);
if (ret) {
- wfx_tx_unlock(wvif->wdev);
- return -EIO;
+ ret = -EIO;
+ goto err_scan_start;
}
ret = wait_for_completion_timeout(&wvif->scan_complete, timeout);
- if (req->channels[start_idx]->max_power != wvif->vif->bss_conf.txpower)
- hif_set_output_power(wvif, wvif->vif->bss_conf.txpower);
- wfx_tx_unlock(wvif->wdev);
if (!ret) {
dev_notice(wvif->wdev->dev, "scan timeout\n");
hif_stop_scan(wvif);
- return -ETIMEDOUT;
+ ret = wait_for_completion_timeout(&wvif->scan_complete, 1 * HZ);
+ if (!ret)
+ dev_err(wvif->wdev->dev, "scan didn't stop\n");
+ ret = -ETIMEDOUT;
+ goto err_timeout;
}
if (wvif->scan_abort) {
dev_notice(wvif->wdev->dev, "scan abort\n");
- return -ECONNABORTED;
+ ret = -ECONNABORTED;
+ goto err_timeout;
}
- return i - start_idx;
+ ret = i - start_idx;
+err_timeout:
+ if (req->channels[start_idx]->max_power != wvif->vif->bss_conf.txpower)
+ hif_set_output_power(wvif, wvif->vif->bss_conf.txpower);
+err_scan_start:
+ wfx_tx_unlock(wvif->wdev);
+ return ret;
}

/*
--
2.33.0