diff options
| author | Konrad Leszczynski <konrad.leszczynski@intel.com> | 2016-02-24 10:47:12 +0000 |
|---|---|---|
| committer | Badhri Jagan Sridharan <badhri@google.com> | 2017-05-03 18:06:18 +0000 |
| commit | 4f8785184972bf230383dfbbda3e1c0b21dc2312 (patch) | |
| tree | 951f92dec833cb3084d9c6505bd8e4616677fa35 /drivers/usb/gadget/function | |
| parent | 69a14c17de7edbaa354d56bbd25718a6e2cd6089 (diff) | |
ANDROID: usb: gadget: f_audio_source: disable the CPU C-states upon playback
Due to the issue with the isoc transfers being interrupted
by the CPU going into the idle state, the C-states will be
disabled for the playback time.
Change-Id: If4e52673606923d7e33a1d1dbe0192b8ad24f78c
Signed-off-by: Konrad Leszczynski <konrad.leszczynski@intel.com>
Signed-off-by: Russ Weight <russell.h.weight@intel.com>
Diffstat (limited to 'drivers/usb/gadget/function')
| -rw-r--r-- | drivers/usb/gadget/function/f_audio_source.c | 11 |
1 files changed, 11 insertions, 0 deletions
diff --git a/drivers/usb/gadget/function/f_audio_source.c b/drivers/usb/gadget/function/f_audio_source.c index db7903d19c43..8124af33b738 100644 --- a/drivers/usb/gadget/function/f_audio_source.c +++ b/drivers/usb/gadget/function/f_audio_source.c @@ -17,6 +17,7 @@ #include <linux/device.h> #include <linux/usb/audio.h> #include <linux/wait.h> +#include <linux/pm_qos.h> #include <sound/core.h> #include <sound/initval.h> #include <sound/pcm.h> @@ -268,6 +269,8 @@ struct audio_dev { /* number of frames sent since start_time */ s64 frames_sent; struct audio_source_config *config; + /* for creating and issuing QoS requests */ + struct pm_qos_request pm_qos; }; static inline struct audio_dev *func_to_audio(struct usb_function *f) @@ -740,6 +743,10 @@ static int audio_pcm_open(struct snd_pcm_substream *substream) runtime->hw.channels_max = 2; audio->substream = substream; + + /* Add the QoS request and set the latency to 0 */ + pm_qos_add_request(&audio->pm_qos, PM_QOS_CPU_DMA_LATENCY, 0); + return 0; } @@ -749,6 +756,10 @@ static int audio_pcm_close(struct snd_pcm_substream *substream) unsigned long flags; spin_lock_irqsave(&audio->lock, flags); + + /* Remove the QoS request */ + pm_qos_remove_request(&audio->pm_qos); + audio->substream = NULL; spin_unlock_irqrestore(&audio->lock, flags); |