Hi, > -----Original Message----- > From: linux-bluetooth-owner@xxxxxxxxxxxxxxx [mailto:linux-bluetooth- > owner@xxxxxxxxxxxxxxx] On Behalf Of Johan Hedberg > Sent: Thursday, January 05, 2012 4:20 PM > To: Aj, SanthoshX > Cc: linux-bluetooth@xxxxxxxxxxxxxxx; Holtmann, Marcel; Nair, Rashmi G > Subject: Re: [PATCH] Breaks in A2DP playback during device search > > Hi, > > On Thu, Jan 05, 2012, Aj, SanthoshX wrote: > > From 8ecb4074305613a113d1c8dd220ab856c5f7ebc1 Mon Sep 17 00:00:00 2001 > > From: Santhosh <santhoshx.aj@xxxxxxxxx> > > Date: Wed, 4 Jan 2012 12:44:37 +0530 > > Subject: [PATCH] To change the latency of controller > > This change is done to fix the a2dp breaks as the IMC controller > > expects the latency to be set explicitly by calling HCI QoS setup > > > > --- > > audio/device.c | 7 +++ > > common/Android.mk | 3 +- > > common/android_bluez.c | 111 ++++++++++++++++++++++++++++++++++++++- > -------- > > 3 files changed, 98 insertions(+), 23 deletions(-) > > As was previously mentioned by others patches to this list are expected > to be against the upstream git tree. This looks like something else. One > thing I'd like to add though: > > > +static int vendor_high_priority(int fd, uint16_t handle) { > > + unsigned char hci_sleep_cmd[] = { > > + 0x01, // HCI command packet > > + 0x57, 0xfc, // HCI_Write_High_Priority_Connection > > + 0x02, // Length > > + 0x00, 0x00 // Handle > > + }; > > + > > + hci_sleep_cmd[4] = (uint8_t)handle; > > + hci_sleep_cmd[5] = (uint8_t)(handle >> 8); > > + > > + int ret = write(fd, hci_sleep_cmd, sizeof(hci_sleep_cmd)); > > + if (ret < 0) { > > + error("write(): %s (%d)]", strerror(errno), errno); > > + return -1; > > + } else if (ret != sizeof(hci_sleep_cmd)) { > > + error("write(): unexpected length %d", ret); > > + return -1; > > + } > > + return 0; > > +} > > When you need to need to create a mechanism which controls some aspect > of an RFCOMM, L2CAP or ACL link your first option should be to consider > implementing it as a socket option. If that's not possible (though in > this case I think it is) then the only other alternative is to abstract > it behind the adapter_ops interface since the core daemon shouldn't any > longer do direct HCI access. So you'd implement sending this command in > hciops and then add the appropriate mgmt command and add support for it > into mgmtops.c and the kernel. I work in TI (with Chen Ganir and Ilia Kolominsky), We encountered the same dilemma and suggested a solution using Flow specification. The Flow Specification HCI relates to an ACL handle and not a specific L2CAP channel. If we intend to configure the Flow Spec using socket option then different profiles might overrun each other settings. The other option of using the mgmt is not too good either. Since this command is "Link" related and not "Adapter/Device" related, the daemon dbus API would have to receive the ACL handle as parameter or introduce a new property on Device node which might not exist. Note that one can create an L2CAP socket without interfacing the daemon. My humble opinion is to set the Flow Spec per socket (l2cap/rfcomm) using socket options. Store it per channel and send accumulated flow spec on every change per ACL. - channel changed its flow sepc - channel with flow spec was closed All done in the kernel, no changes to the daemon. Kind Regards, Amir Hadar -- To unsubscribe from this list: send the line "unsubscribe linux-bluetooth" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
