[PATCH] ath10k: fix invalid NSS for 4x4 devices

[PATCH] ath10k: fix invalid NSS for 4x4 devices

[Rajkumar Manoharan]

The number of spatial streams that are derived from chain mask
for 4x4 devices is using wrong bitmask and conditional check.
This is affecting downlink throughput for QCA99x0 devices. Earlier
cfg_tx_chainmask is not filled by default until user configured it
and so get_nss_from_chainmask never be called. This issue is exposed
by recent commit 166de3f1895d ("ath10k: remove supported chain mask").
By default maximum supported chain mask is filled in cfg_tx_chainmask.

Cc: stable@vger.kernel.org
Fixes: 5572a95b4b ("ath10k: apply chainmask settings to vdev on
creation")
Signed-off-by: Rajkumar Manoharan <rmanohar@qti.qualcomm.com>
---
 drivers/net/wireless/ath/ath10k/mac.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/net/wireless/ath/ath10k/mac.c b/drivers/net/wireless/ath/ath10k/mac.c
index a7411fe..95a55405 100644
--- a/drivers/net/wireless/ath/ath10k/mac.c
+++ b/drivers/net/wireless/ath/ath10k/mac.c
@@ -4225,7 +4225,7 @@ static int ath10k_config(struct ieee80211_hw *hw, u32 changed)
 
 static u32 get_nss_from_chainmask(u16 chain_mask)
 {
-	if ((chain_mask & 0x15) == 0x15)
+	if ((chain_mask & 0xf) == 0xf)
 		return 4;
 	else if ((chain_mask & 0x7) == 0x7)
 		return 3;
-- 
2.6.2

Re: [PATCH] ath10k: fix invalid NSS for 4x4 devices

[Ben Greear]

I'm a bit embarrassed about that 0x15..thanks for catching that!

Ben

On 11/02/2015 10:21 PM, Rajkumar Manoharan wrote:
> The number of spatial streams that are derived from chain mask
> for 4x4 devices is using wrong bitmask and conditional check.
> This is affecting downlink throughput for QCA99x0 devices. Earlier
> cfg_tx_chainmask is not filled by default until user configured it
> and so get_nss_from_chainmask never be called. This issue is exposed
> by recent commit 166de3f1895d ("ath10k: remove supported chain mask").
> By default maximum supported chain mask is filled in cfg_tx_chainmask.
>
> Cc: stable@vger.kernel.org
> Fixes: 5572a95b4b ("ath10k: apply chainmask settings to vdev on
> creation")
> Signed-off-by: Rajkumar Manoharan <rmanohar@qti.qualcomm.com>
> ---
>   drivers/net/wireless/ath/ath10k/mac.c | 2 +-
>   1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/drivers/net/wireless/ath/ath10k/mac.c b/drivers/net/wireless/ath/ath10k/mac.c
> index a7411fe..95a55405 100644
> --- a/drivers/net/wireless/ath/ath10k/mac.c
> +++ b/drivers/net/wireless/ath/ath10k/mac.c
> @@ -4225,7 +4225,7 @@ static int ath10k_config(struct ieee80211_hw *hw, u32 changed)
>
>   static u32 get_nss_from_chainmask(u16 chain_mask)
>   {
> -	if ((chain_mask & 0x15) == 0x15)
> +	if ((chain_mask & 0xf) == 0xf)
>   		return 4;
>   	else if ((chain_mask & 0x7) == 0x7)
>   		return 3;
>

-- 
Ben Greear <greearb@candelatech.com>
Candela Technologies Inc  http://www.candelatech.com

Re: [PATCH] ath10k: fix invalid NSS for 4x4 devices

[Kalle Valo]

Rajkumar Manoharan <rmanohar@qti.qualcomm.com> writes:

> The number of spatial streams that are derived from chain mask
> for 4x4 devices is using wrong bitmask and conditional check.
> This is affecting downlink throughput for QCA99x0 devices. Earlier
> cfg_tx_chainmask is not filled by default until user configured it
> and so get_nss_from_chainmask never be called. This issue is exposed
> by recent commit 166de3f1895d ("ath10k: remove supported chain mask").
> By default maximum supported chain mask is filled in cfg_tx_chainmask.
>
> Cc: stable@vger.kernel.org
> Fixes: 5572a95b4b ("ath10k: apply chainmask settings to vdev on
> creation")
> Signed-off-by: Rajkumar Manoharan <rmanohar@qti.qualcomm.com>

I'm planning to send this to 4.3-rc releases.

-- 
Kalle Valo

Re: [PATCH] ath10k: fix invalid NSS for 4x4 devices

[Kalle Valo]

Rajkumar Manoharan <rmanohar@qti.qualcomm.com> writes:

> The number of spatial streams that are derived from chain mask
> for 4x4 devices is using wrong bitmask and conditional check.
> This is affecting downlink throughput for QCA99x0 devices. Earlier
> cfg_tx_chainmask is not filled by default until user configured it
> and so get_nss_from_chainmask never be called. This issue is exposed
> by recent commit 166de3f1895d ("ath10k: remove supported chain mask").
> By default maximum supported chain mask is filled in cfg_tx_chainmask.
>
> Cc: stable@vger.kernel.org
> Fixes: 5572a95b4b ("ath10k: apply chainmask settings to vdev on
> creation")
> Signed-off-by: Rajkumar Manoharan <rmanohar@qti.qualcomm.com>

Applied to ath-current, thanks.

-- 
Kalle Valo