2019-06-11 12:28:05

by Sven Eckelmann

[permalink] [raw]
Subject: [PATCH] ath10k: fix max antenna gain unit

From: Sven Eckelmann <[email protected]>

Most of the txpower for the ath10k firmware is stored as twicepower (0.5 dB
steps). This isn't the case for max_antenna_gain - which is still expected
by the firmware as dB.

The firmware is converting it from dB to the internal (twicepower)
representation when it calculates the limits of a channel. This can be seen
in tpc_stats when configuring "12" as max_antenna_gain. Instead of the
expected 12 (6 dB), the tpc_stats shows 24 (12 dB).

Tested on QCA9888 and IPQ4019 with firmware 10.4-3.5.3-00057.

Fixes: 02256930d9b8 ("ath10k: use proper tx power unit")
Signed-off-by: Sven Eckelmann <[email protected]>
---
Cc: Michal Kazior <[email protected]>

drivers/net/wireless/ath/ath10k/mac.c | 6 +++---
1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/drivers/net/wireless/ath/ath10k/mac.c b/drivers/net/wireless/ath/ath10k/mac.c
index 9c703d287333..35d026a2772a 100644
--- a/drivers/net/wireless/ath/ath10k/mac.c
+++ b/drivers/net/wireless/ath/ath10k/mac.c
@@ -1008,7 +1008,7 @@ static int ath10k_monitor_vdev_start(struct ath10k *ar, int vdev_id)
arg.channel.min_power = 0;
arg.channel.max_power = channel->max_power * 2;
arg.channel.max_reg_power = channel->max_reg_power * 2;
- arg.channel.max_antenna_gain = channel->max_antenna_gain * 2;
+ arg.channel.max_antenna_gain = channel->max_antenna_gain;

reinit_completion(&ar->vdev_setup_done);

@@ -1450,7 +1450,7 @@ static int ath10k_vdev_start_restart(struct ath10k_vif *arvif,
arg.channel.min_power = 0;
arg.channel.max_power = chandef->chan->max_power * 2;
arg.channel.max_reg_power = chandef->chan->max_reg_power * 2;
- arg.channel.max_antenna_gain = chandef->chan->max_antenna_gain * 2;
+ arg.channel.max_antenna_gain = chandef->chan->max_antenna_gain;

if (arvif->vdev_type == WMI_VDEV_TYPE_AP) {
arg.ssid = arvif->u.ap.ssid;
@@ -3105,7 +3105,7 @@ static int ath10k_update_channel_list(struct ath10k *ar)
ch->min_power = 0;
ch->max_power = channel->max_power * 2;
ch->max_reg_power = channel->max_reg_power * 2;
- ch->max_antenna_gain = channel->max_antenna_gain * 2;
+ ch->max_antenna_gain = channel->max_antenna_gain;
ch->reg_class_id = 0; /* FIXME */

/* FIXME: why use only legacy modes, why not any
--
2.20.1


2019-06-11 16:55:36

by Ben Greear

[permalink] [raw]
Subject: Re: [PATCH] ath10k: fix max antenna gain unit

On 6/11/19 5:19 AM, Sven Eckelmann wrote:
> From: Sven Eckelmann <[email protected]>
>
> Most of the txpower for the ath10k firmware is stored as twicepower (0.5 dB
> steps). This isn't the case for max_antenna_gain - which is still expected
> by the firmware as dB.
>
> The firmware is converting it from dB to the internal (twicepower)
> representation when it calculates the limits of a channel. This can be seen
> in tpc_stats when configuring "12" as max_antenna_gain. Instead of the
> expected 12 (6 dB), the tpc_stats shows 24 (12 dB).
>
> Tested on QCA9888 and IPQ4019 with firmware 10.4-3.5.3-00057.

I did a visual inspection of wave-1 firmware source and it appears this change would be correct
for it as well.

I would also suggest updating the comments in the wmi.h structure to document the
units.

Thanks,
Ben

>
> Fixes: 02256930d9b8 ("ath10k: use proper tx power unit")
> Signed-off-by: Sven Eckelmann <[email protected]>
> ---
> Cc: Michal Kazior <[email protected]>
>
> drivers/net/wireless/ath/ath10k/mac.c | 6 +++---
> 1 file changed, 3 insertions(+), 3 deletions(-)
>
> diff --git a/drivers/net/wireless/ath/ath10k/mac.c b/drivers/net/wireless/ath/ath10k/mac.c
> index 9c703d287333..35d026a2772a 100644
> --- a/drivers/net/wireless/ath/ath10k/mac.c
> +++ b/drivers/net/wireless/ath/ath10k/mac.c
> @@ -1008,7 +1008,7 @@ static int ath10k_monitor_vdev_start(struct ath10k *ar, int vdev_id)
> arg.channel.min_power = 0;
> arg.channel.max_power = channel->max_power * 2;
> arg.channel.max_reg_power = channel->max_reg_power * 2;
> - arg.channel.max_antenna_gain = channel->max_antenna_gain * 2;
> + arg.channel.max_antenna_gain = channel->max_antenna_gain;
>
> reinit_completion(&ar->vdev_setup_done);
>
> @@ -1450,7 +1450,7 @@ static int ath10k_vdev_start_restart(struct ath10k_vif *arvif,
> arg.channel.min_power = 0;
> arg.channel.max_power = chandef->chan->max_power * 2;
> arg.channel.max_reg_power = chandef->chan->max_reg_power * 2;
> - arg.channel.max_antenna_gain = chandef->chan->max_antenna_gain * 2;
> + arg.channel.max_antenna_gain = chandef->chan->max_antenna_gain;
>
> if (arvif->vdev_type == WMI_VDEV_TYPE_AP) {
> arg.ssid = arvif->u.ap.ssid;
> @@ -3105,7 +3105,7 @@ static int ath10k_update_channel_list(struct ath10k *ar)
> ch->min_power = 0;
> ch->max_power = channel->max_power * 2;
> ch->max_reg_power = channel->max_reg_power * 2;
> - ch->max_antenna_gain = channel->max_antenna_gain * 2;
> + ch->max_antenna_gain = channel->max_antenna_gain;
> ch->reg_class_id = 0; /* FIXME */
>
> /* FIXME: why use only legacy modes, why not any
>


--
Ben Greear <[email protected]>
Candela Technologies Inc http://www.candelatech.com