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path: root/sound/usb/line6/capture.h
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2015-01-28ALSA: line6: Reorganize PCM stream handlingTakashi Iwai
The current code deals with the stream start / stop solely via line6_pcm_acquire() and line6_pcm_release(). This was (supposedly) intended to avoid the races, but it doesn't work as expected. The concurrent acquire and release calls can be performed without proper protections, thus this might result in memory corruption. Furthermore, we can't take a mutex to protect the whole function because it can be called from the PCM trigger callback that is an atomic context. Also spinlock isn't appropriate because the function allocates with kmalloc with GFP_KERNEL. That is, these function just lead to singular problems. This is an attempt to reduce the existing races. First off, separate both the stream buffer management and the stream URB management. The former is protected via a newly introduced state_mutex while the latter is protected via each line6_pcm_stream lock. Secondly, the stream state are now managed in opened and running bit flags of each line6_pcm_stream. Not only this a bit clearer than previous combined bit flags, this also gives a better abstraction. These rewrites allows us to make common hw_params and hw_free callbacks for both playback and capture directions. For the monitor and impulse operations, still line6_pcm_acquire() and line6_pcm_release() are used. They call internally the corresponding functions for both playback and capture streams with proper lock or mutex. Unlike the previous versions, these function don't take the bit masks but the only single type value. Also they are supposed to be applied only as duplex operations. Tested-by: Chris Rorvick <chris@rorvick.com> Signed-off-by: Takashi Iwai <tiwai@suse.de>
2015-01-28ALSA: line6: Consolidate PCM stream buffer allocation and freeTakashi Iwai
The PCM stream buffer allocation and free are identical for both playback and capture streams. Provide single helper functions. These are used only in pcm.c, thus they can be even static. Tested-by: Chris Rorvick <chris@rorvick.com> Signed-off-by: Takashi Iwai <tiwai@suse.de>
2015-01-28ALSA: line6: Consolidate URB unlink and sync helpersTakashi Iwai
The codes to unlink and sync URBs are identical for both playback and capture streams. Consolidate to single helper functions. Tested-by: Chris Rorvick <chris@rorvick.com> Signed-off-by: Takashi Iwai <tiwai@suse.de>
2015-01-20ALSA: line6: Remove driver version from header commentChris Rorvick
The driver version string was removed in an ealier commit for being useless. These are equally useless. Signed-off-by: Chris Rorvick <chris@rorvick.com> Signed-off-by: Takashi Iwai <tiwai@suse.de>
2015-01-20ALSA: line6: Refer to manufacturer as "Line 6"Chris Rorvick
The correct spelling includes the space. Fix this in strings and comments that refer to the manufacturer. Signed-off-by: Chris Rorvick <chris@rorvick.com> Signed-off-by: Takashi Iwai <tiwai@suse.de>
2015-01-12ALSA: move line6 usb driver into sound/usbTakashi Iwai
Promote line6 driver from staging to sound/usb/line6 directory, and maintain through sound subsystem tree. This commit just moves the code and adapts Makefile / Kconfig. The further renames and misc cleanups will follow. Signed-off-by: Takashi Iwai <tiwai@suse.de>