Re: [PATCH] Bluetooth: Send HCI Set Event Mask Page 2 command only when needed

[Szymon Janc <szymon.janc@codecoup.pl>]

Hi Marcel,

On Friday, 9 June 2017 18:43:56 CEST Marcel Holtmann wrote:
> The Broadcom BCM20702 Bluetooth controller in ThinkPad-T530 devices
> report support for the Set Event Mask Page 2 command, but actually do
> return an error when trying to use it.
> 
>   < HCI Command: Read Local Supported Commands (0x04|0x0002) plen 0
> 
>   > HCI Event: Command Complete (0x0e) plen 68
> 
>        Read Local Supported Commands (0x04|0x0002) ncmd 1
>          Status: Success (0x00)
>          Commands: 162 entries
>            ...
>            Set Event Mask Page 2 (Octet 22 - Bit 2)
>            ...
> 
>   < HCI Command: Set Event Mask Page 2 (0x03|0x0063) plen 8
>          Mask: 0x0000000000000000
> 
>   > HCI Event: Command Complete (0x0e) plen 4
> 
>        Set Event Mask Page 2 (0x03|0x0063) ncmd 1
>          Status: Unknown HCI Command (0x01)
> 
> Since these controllers do not support any feature that would require
> the event mask page 2 to be modified, it is safe to not send this
> command at all. The default value is all bits set to zero.
> 
> T:  Bus=01 Lev=02 Prnt=02 Port=03 Cnt=03 Dev#=  9 Spd=12   MxCh= 0
> D:  Ver= 2.00 Cls=ff(vend.) Sub=01 Prot=01 MxPS=64 #Cfgs=  1
> P:  Vendor=0a5c ProdID=21e6 Rev= 1.12
> S:  Manufacturer=Broadcom Corp
> S:  Product=BCM20702A0
> S:  SerialNumber=F82FA8E8CFC0
> C:* #Ifs= 4 Cfg#= 1 Atr=e0 MxPwr=  0mA
> I:* If#= 0 Alt= 0 #EPs= 3 Cls=ff(vend.) Sub=01 Prot=01 Driver=btusb
> E:  Ad=81(I) Atr=03(Int.) MxPS=  16 Ivl=1ms
> E:  Ad=82(I) Atr=02(Bulk) MxPS=  64 Ivl=0ms
> E:  Ad=02(O) Atr=02(Bulk) MxPS=  64 Ivl=0ms
> I:* If#= 1 Alt= 0 #EPs= 2 Cls=ff(vend.) Sub=01 Prot=01 Driver=btusb
> E:  Ad=83(I) Atr=01(Isoc) MxPS=   0 Ivl=1ms
> E:  Ad=03(O) Atr=01(Isoc) MxPS=   0 Ivl=1ms
> I:  If#= 1 Alt= 1 #EPs= 2 Cls=ff(vend.) Sub=01 Prot=01 Driver=btusb
> E:  Ad=83(I) Atr=01(Isoc) MxPS=   9 Ivl=1ms
> E:  Ad=03(O) Atr=01(Isoc) MxPS=   9 Ivl=1ms
> I:  If#= 1 Alt= 2 #EPs= 2 Cls=ff(vend.) Sub=01 Prot=01 Driver=btusb
> E:  Ad=83(I) Atr=01(Isoc) MxPS=  17 Ivl=1ms
> E:  Ad=03(O) Atr=01(Isoc) MxPS=  17 Ivl=1ms
> I:  If#= 1 Alt= 3 #EPs= 2 Cls=ff(vend.) Sub=01 Prot=01 Driver=btusb
> E:  Ad=83(I) Atr=01(Isoc) MxPS=  25 Ivl=1ms
> E:  Ad=03(O) Atr=01(Isoc) MxPS=  25 Ivl=1ms
> I:  If#= 1 Alt= 4 #EPs= 2 Cls=ff(vend.) Sub=01 Prot=01 Driver=btusb
> E:  Ad=83(I) Atr=01(Isoc) MxPS=  33 Ivl=1ms
> E:  Ad=03(O) Atr=01(Isoc) MxPS=  33 Ivl=1ms
> I:  If#= 1 Alt= 5 #EPs= 2 Cls=ff(vend.) Sub=01 Prot=01 Driver=btusb
> E:  Ad=83(I) Atr=01(Isoc) MxPS=  49 Ivl=1ms
> E:  Ad=03(O) Atr=01(Isoc) MxPS=  49 Ivl=1ms
> I:* If#= 2 Alt= 0 #EPs= 2 Cls=ff(vend.) Sub=ff Prot=ff Driver=btusb
> E:  Ad=84(I) Atr=02(Bulk) MxPS=  32 Ivl=0ms
> E:  Ad=04(O) Atr=02(Bulk) MxPS=  32 Ivl=0ms
> I:* If#= 3 Alt= 0 #EPs= 0 Cls=fe(app. ) Sub=01 Prot=01 Driver=(none)
> 
> Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
> ---
>  net/bluetooth/hci_core.c | 17 +++++++++++++++--
>  1 file changed, 15 insertions(+), 2 deletions(-)
> 
> diff --git a/net/bluetooth/hci_core.c b/net/bluetooth/hci_core.c
> index 7655b4005dfb..93806b959039 100644
> --- a/net/bluetooth/hci_core.c
> +++ b/net/bluetooth/hci_core.c
> @@ -548,6 +548,7 @@ static void hci_set_event_mask_page_2(struct hci_request
> *req) {
>  	struct hci_dev *hdev = req->hdev;
>  	u8 events[8] = { 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00 };
> +	bool changed = false;
> 
>  	/* If Connectionless Slave Broadcast master role is supported
>  	 * enable all necessary events for it.
> @@ -557,6 +558,7 @@ static void hci_set_event_mask_page_2(struct hci_request
> *req) events[1] |= 0x80;	/* Synchronization Train Complete */
>  		events[2] |= 0x10;	/* Slave Page Response Timeout */
>  		events[2] |= 0x20;	/* CSB Channel Map Change */
> +		changed = true;
>  	}
> 
>  	/* If Connectionless Slave Broadcast slave role is supported
> @@ -567,13 +569,24 @@ static void hci_set_event_mask_page_2(struct
> hci_request *req) events[2] |= 0x02;	/* CSB Receive */
>  		events[2] |= 0x04;	/* CSB Timeout */
>  		events[2] |= 0x08;	/* Truncated Page Complete */
> +		changed = true;
>  	}
> 
>  	/* Enable Authenticated Payload Timeout Expired event if supported */
> -	if (lmp_ping_capable(hdev) || hdev->le_features[0] & HCI_LE_PING)
> +	if (lmp_ping_capable(hdev) || hdev->le_features[0] & HCI_LE_PING) {
>  		events[2] |= 0x80;
> +		changed = true;
> +	}
> 
> -	hci_req_add(req, HCI_OP_SET_EVENT_MASK_PAGE_2, sizeof(events), events);
> +	/* Some Broadcom based controllers indicate support for Set Event
> +	 * Mask Page 2 command, but then actually do not support it. Since
> +	 * the default value is all bits set to zero, the command is only
> +	 * required if the event mask has to be changed. In case no change
> +	 * to the event mask is needed, skip this command.
> +	 */
> +	if (changed)
> +		hci_req_add(req, HCI_OP_SET_EVENT_MASK_PAGE_2,
> +			    sizeof(events), events);
>  }
> 
>  static int hci_init3_req(struct hci_request *req, unsigned long opt)

Applied to bluetooth-next tree. Thanks.

-- 
pozdrawiam
Szymon Janc