Received-SPF: pass (google.com: domain of linux-wireless-owner@vger.kernel.org designates 23.128.96.18 as permitted sender) client-ip=23.128.96.18;
Subject: Re: [PATCH] carl9170: remove P2P_GO support
To:     Christian Lamparter <chunkeey@gmail.com>,
        linux-wireless@vger.kernel.org
Cc:     Kalle Valo <kvalo@codeaurora.org>
References: <20200425092811.9494-1-chunkeey@gmail.com>
From:   =?UTF-8?Q?Frank_Sch=c3=a4fer?= <fschaefer.oss@googlemail.com>
Message-ID: <5ebf8e6d-d34b-aa92-d166-d8a5ca0b2c18@googlemail.com>
Date:   Sun, 26 Apr 2020 12:33:13 +0200
User-Agent: Mozilla/5.0 (X11; Linux i686; rv:68.0) Gecko/20100101
 Thunderbird/68.4.1
MIME-Version: 1.0
In-Reply-To: <20200425092811.9494-1-chunkeey@gmail.com>
Content-Type: text/plain; charset=utf-8; format=flowed
Content-Transfer-Encoding: 8bit
Content-Language: de-DE
Sender: linux-wireless-owner@vger.kernel.org
Precedence: bulk

Hi Christian,

Am 25.04.20 um 11:28 schrieb Christian Lamparter:
> This patch follows up on a bug-report by Frank Schäfer that
> discovered P2P GO wasn't working with wpa_supplicant.
> This patch removes part of the broken P2P GO support but
> keeps the vif switchover code in place.
Hmm... no way to fix it ?
P2P-GO seems to work fine with p2p_no_group_iface=1, so do you really 
think it's a good idea / required to remove the whole thing ?

> Cc: <stable@vger.kernel.org>
Are you sure about that ?
People might be using it...

Regards,
Frank

> Link: <https://lkml.kernel.org/r/3a9d86b6-744f-e670-8792-9167257edef8@googlemail.com>
> Reported-by: Frank Schäfer <fschaefer.oss@googlemail.com>
> Signed-off-by: Christian Lamparter <chunkeey@gmail.com>
> ---
>   drivers/net/wireless/ath/carl9170/fw.c   |  4 +---
>   drivers/net/wireless/ath/carl9170/main.c | 21 ++++-----------------
>   2 files changed, 5 insertions(+), 20 deletions(-)
>
> diff --git a/drivers/net/wireless/ath/carl9170/fw.c b/drivers/net/wireless/ath/carl9170/fw.c
> index 51934d191f33..1ab09e1c9ec5 100644
> --- a/drivers/net/wireless/ath/carl9170/fw.c
> +++ b/drivers/net/wireless/ath/carl9170/fw.c
> @@ -338,9 +338,7 @@ static int carl9170_fw(struct ar9170 *ar, const __u8 *data, size_t len)
>   		ar->hw->wiphy->interface_modes |= BIT(NL80211_IFTYPE_ADHOC);
>   
>   		if (SUPP(CARL9170FW_WLANTX_CAB)) {
> -			if_comb_types |=
> -				BIT(NL80211_IFTYPE_AP) |
> -				BIT(NL80211_IFTYPE_P2P_GO);
> +			if_comb_types |= BIT(NL80211_IFTYPE_AP);
>   
>   #ifdef CONFIG_MAC80211_MESH
>   			if_comb_types |=
> diff --git a/drivers/net/wireless/ath/carl9170/main.c b/drivers/net/wireless/ath/carl9170/main.c
> index 5914926a5c5b..816929fb5b14 100644
> --- a/drivers/net/wireless/ath/carl9170/main.c
> +++ b/drivers/net/wireless/ath/carl9170/main.c
> @@ -582,11 +582,10 @@ static int carl9170_init_interface(struct ar9170 *ar,
>   	ar->disable_offload |= ((vif->type != NL80211_IFTYPE_STATION) &&
>   	    (vif->type != NL80211_IFTYPE_AP));
>   
> -	/* While the driver supports HW offload in a single
> -	 * P2P client configuration, it doesn't support HW
> -	 * offload in the favourit, concurrent P2P GO+CLIENT
> -	 * configuration. Hence, HW offload will always be
> -	 * disabled for P2P.
> +	/* The driver used to have P2P GO+CLIENT support,
> +	 * but since this was dropped and we don't know if
> +	 * there are any gremlins lurking in the shadows,
> +	 * so best we keep HW offload disabled for P2P.
>   	 */
>   	ar->disable_offload |= vif->p2p;
>   
> @@ -639,18 +638,6 @@ static int carl9170_op_add_interface(struct ieee80211_hw *hw,
>   			if (vif->type == NL80211_IFTYPE_STATION)
>   				break;
>   
> -			/* P2P GO [master] use-case
> -			 * Because the P2P GO station is selected dynamically
> -			 * by all participating peers of a WIFI Direct network,
> -			 * the driver has be able to change the main interface
> -			 * operating mode on the fly.
> -			 */
> -			if (main_vif->p2p && vif->p2p &&
> -			    vif->type == NL80211_IFTYPE_AP) {
> -				old_main = main_vif;
> -				break;
> -			}
> -
>   			err = -EBUSY;
>   			rcu_read_unlock();