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path: root/sound/firewire/dice/dice-transaction.c
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2014-12-10ALSA: dice: Support for non SYT-Match sampling clock source modeTakashi Sakamoto
This commit allows this driver to handle devices with non SYT-Match sampling clock source. When sampling clock source is SYT-Match mode, devices handle 'presentation timestamp' in received packets and generates sampling clock according to the information. In this case, driver is synchronization master and must transfer correct value in SYT field of each packets in outgoing stream, then the outgoing stream is a master stream. On the other hand, non SYT-Match mode, devices do this. So drivers must pick up the value in SYT field of incoming packets and use the value for outgoing stream. Currently firewire-lib module achieve this work. Furthermore, without SYT-Match and internal clock source, the sampling rate should be fixed for the other devices connected to the handled device. This commit add a restriction of sampling rate at this situation. With these implementations, this driver has no need to set clock source. This commit remove set function. Signed-off-by: Takashi Sakamoto <o-takashi@sakamocchi.jp> Acked-by: Clemens Ladisch <clemens@ladisch.de> Signed-off-by: Takashi Iwai <tiwai@suse.de>
2014-12-01ALSA: dice: fix semicolon.cocci warningsFengguang Wu
sound/firewire/dice/dice-transaction.c:34:2-3: Unneeded semicolon Removes unneeded semicolon. Generated by: scripts/coccinelle/misc/semicolon.cocci CC: Takashi Sakamoto <o-takashi@sakamocchi.jp> Signed-off-by: Fengguang Wu <fengguang.wu@intel.com> Signed-off-by: Takashi Iwai <tiwai@suse.de>
2014-11-29ALSA: dice: Split transaction functionality into a fileTakashi Sakamoto
This commit adds a file with some helper functions for transaction, and move some codes into the file with some arrangements. For Dice chipset, well-known FCP or AV/C commands are not used to control devices. It's achieved by read/write transactions into specific addresses. Dice's address area is split into 5 areas. Each area has its own role. The offset for each area can be got by reading head of the address area. By reading these areas, drivers can get to know device status. By writing these areas, drivers can change device status. Dice has a specific mechanism called as 'notification'. When device status is changed, Dice devices tells the event by sending transaction. This notification is sent to an address which drivers register in advance. But this causes an issue to drivers. To handle the notification, drivers need to allocate its own callback function to the address region in host controller. This region is exclusive. For the other applications, drivers must give a mechanism to read the received notification. For this purpose, Dice driver already implements hwdep interface. Dice chipset doesn't allow drivers to register several addresses. In this reason, when this driver is applied to a device, the other drivers should _not_ try to register its own address to the device. Signed-off-by: Takashi Sakamoto <o-takashi@sakamocchi.jp> Signed-off-by: Takashi Iwai <tiwai@suse.de>