ath9k: Remove ath9k rate control

There is no benefit in retaining the legacy rate control module
in the driver codebase.

It is known to be buggy and has less than optimal performance
in real-world environments compared with minstrel. The only
reason that it was kept when we made the switch to minstrel
as default was that it showed higher throughput numbers in a
clean/ideal environment.

This is no longer the case and minstrel can push ath9k to
the same throughput levels. In TCP, with 3-stream cards, more than
295 Mbps can be obtained in open air, with 2-stream cards,
210 Mbps is easily reached. To test performance issues,
instead of using a broken rate control module, it is better
to use the fixed-rate interface provided by mac80211 anyway.

The ath9k RC has not received any bug fixes in years and is
just bit-rotting away - this patch removes it.

Signed-off-by: Sujith Manoharan <c_manoha@qca.qualcomm.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

1 files changed, 1 insertions, 13 deletions

diff --git a/drivers/net/wireless/ath/ath9k/init.c b/drivers/net/wireless/ath/ath9k/init.c
index 00e0f606a0d3..67411d21c9a5 100644
--- a/drivers/net/wireless/ath/ath9k/init.c
+++ b/drivers/net/wireless/ath/ath9k/init.c
@@ -1100,19 +1100,11 @@ static int __init ath9k_init(void)
 {
 	int error;
 
-	/* Register rate control algorithm */
-	error = ath_rate_control_register();
-	if (error != 0) {
-		pr_err("Unable to register rate control algorithm: %d\n",
-		       error);
-		goto err_out;
-	}
-
 	error = ath_pci_init();
 	if (error < 0) {
 		pr_err("No PCI devices found, driver not installed\n");
 		error = -ENODEV;
-		goto err_rate_unregister;
+		goto err_out;
 	}
 
 	error = ath_ahb_init();
@@ -1125,9 +1117,6 @@ static int __init ath9k_init(void)
 
  err_pci_exit:
 	ath_pci_exit();
-
- err_rate_unregister:
-	ath_rate_control_unregister();
  err_out:
 	return error;
 }
@@ -1138,7 +1127,6 @@ static void __exit ath9k_exit(void)
 	is_ath9k_unloaded = true;
 	ath_ahb_exit();
 	ath_pci_exit();
-	ath_rate_control_unregister();
 	pr_info("%s: Driver unloaded\n", dev_info);
 }
 module_exit(ath9k_exit);