Re: Specifing rate control algorithm?

[jketreno <jketreno@linux.intel.com>]

Johannes Berg wrote:
> On Thu, 2007-05-10 at 09:17 -0700, James Ketrenos wrote:
> 
>> This commit simply adds an optional rate control algorithm name
>> parameter to ieeee80211_register_hw.
> 
> Why don't we just add a char *preferred_rate_control; to the hw
> definition structure instead? That way, we can even show it in
> sys/debugfs later so the user will still know what the driver preferred
> after changing it.
> 
> johannes

How's this?


[PATCH] mac80211: Add preferred_rate_control to ieee80211_hw

There may be a hardware specific rate control algorithm a driver wishes
to use.  Currently, however, the stack assigns the first loaded
algorithm to all drivers calling ieee80211_register_hw.

This commit simply adds an preferred_rate_control to ieee80211_hw and
updates ieee80211_register_hw to use it.

Signed-off-by: James Ketrenos <jketreno@linux.intel.com>
---
 include/net/mac80211.h   |    4 ++++
 net/mac80211/ieee80211.c |   10 +++++++---
 2 files changed, 11 insertions(+), 3 deletions(-)

diff --git a/include/net/mac80211.h b/include/net/mac80211.h
index ef9b613..f9ad839 100644
--- a/include/net/mac80211.h
+++ b/include/net/mac80211.h
@@ -533,6 +533,10 @@ struct ieee80211_hw {
 	/* Number of available hardware TX queues for data packets.
 	 * WMM requires at least four queues. */
 	int queues;
+
+	/* Preferred rate control algorithm. Leave as NULL for stack
+	 * to select algorithm */
+	char *preferred_rate_control;
 };
 
 static inline void SET_IEEE80211_DEV(struct ieee80211_hw *hw, struct device *dev)
diff --git a/net/mac80211/ieee80211.c b/net/mac80211/ieee80211.c
index 873ccb0..6dcc002 100644
--- a/net/mac80211/ieee80211.c
+++ b/net/mac80211/ieee80211.c
@@ -4875,10 +4875,14 @@ int ieee80211_register_hw(struct ieee80211_hw *hw)
 
 	ieee80211_debugfs_add_netdev(IEEE80211_DEV_TO_SUB_IF(local->mdev));
 
-	result = ieee80211_init_rate_ctrl_alg(local, NULL);
+	result = ieee80211_init_rate_ctrl_alg(local, 
+					      hw->preferred_rate_control);
+
 	if (result < 0) {
-		printk(KERN_DEBUG "%s: Failed to initialize rate control "
-		       "algorithm\n", local->mdev->name);
+		printk(KERN_DEBUG "%s: Failed to initialize %s rate control "
+		       "algorithm\n", local->mdev->name,
+		       hw->preferred_rate_control ? 
+		       hw->preferred_rate_control : "default");
 		goto fail_rate;
 	}
 
-- 
1.5.1.3