Instead of suspending/resume the USB device at open()/close(), do it when the device is actually used. This way we can reduce the power consumption when a service is holding the video device and leaving it in an idle state. Reviewed-by: Tomasz Figa <tfiga@xxxxxxxxxxxx> Signed-off-by: Ricardo Ribalda <ribalda@xxxxxxxxxxxx> diff --git a/drivers/media/usb/uvc/uvc_v4l2.c b/drivers/media/usb/uvc/uvc_v4l2.c index 8d5002543e2c..b9642afabd9b 100644 --- a/drivers/media/usb/uvc/uvc_v4l2.c +++ b/drivers/media/usb/uvc/uvc_v4l2.c @@ -25,6 +25,46 @@ #include "uvcvideo.h" +/* ------------------------------------------------------------------------ + * UVC power management + */ + +static int uvc_pm_get(struct uvc_streaming *stream) +{ + int ret = 0; + + ret = usb_autopm_get_interface(stream->dev->intf); + if (ret) + return ret; + + mutex_lock(&stream->dev->lock); + if (!stream->dev->users) + ret = uvc_status_start(stream->dev, GFP_KERNEL); + if (!ret) + stream->dev->users++; + mutex_unlock(&stream->dev->lock); + + if (ret) + usb_autopm_put_interface(stream->dev->intf); + + return ret; +} + +static void uvc_pm_put(struct uvc_streaming *stream) +{ + mutex_lock(&stream->dev->lock); + if (WARN_ON(!stream->dev->users)) { + mutex_unlock(&stream->dev->lock); + return; + } + stream->dev->users--; + if (!stream->dev->users) + uvc_status_stop(stream->dev); + mutex_unlock(&stream->dev->lock); + + usb_autopm_put_interface(stream->dev->intf); +} + /* ------------------------------------------------------------------------ * UVC ioctls */ @@ -249,6 +289,9 @@ static int uvc_v4l2_try_format(struct uvc_streaming *stream, * developers test their webcams with the Linux driver as well as with * the Windows driver). */ + ret = uvc_pm_get(stream); + if (ret) + return ret; mutex_lock(&stream->mutex); if (stream->dev->quirks & UVC_QUIRK_PROBE_EXTRAFIELDS) probe->dwMaxVideoFrameSize = @@ -257,6 +300,7 @@ static int uvc_v4l2_try_format(struct uvc_streaming *stream, /* Probe the device. */ ret = uvc_probe_video(stream, probe); mutex_unlock(&stream->mutex); + uvc_pm_put(stream); if (ret < 0) return ret; @@ -468,7 +512,13 @@ static int uvc_v4l2_set_streamparm(struct uvc_streaming *stream, } /* Probe the device with the new settings. */ + ret = uvc_pm_get(stream); + if (ret) { + mutex_unlock(&stream->mutex); + return ret; + } ret = uvc_probe_video(stream, &probe); + uvc_pm_put(stream); if (ret < 0) { mutex_unlock(&stream->mutex); return ret; @@ -559,36 +609,29 @@ static int uvc_v4l2_open(struct file *file) { struct uvc_streaming *stream; struct uvc_fh *handle; - int ret = 0; stream = video_drvdata(file); uvc_dbg(stream->dev, CALLS, "%s\n", __func__); - ret = usb_autopm_get_interface(stream->dev->intf); - if (ret < 0) - return ret; - /* Create the device handle. */ handle = kzalloc(sizeof(*handle), GFP_KERNEL); - if (handle == NULL) { - usb_autopm_put_interface(stream->dev->intf); + if (!handle) return -ENOMEM; - } - mutex_lock(&stream->dev->lock); - if (stream->dev->users == 0) { - ret = uvc_status_start(stream->dev, GFP_KERNEL); - if (ret < 0) { - mutex_unlock(&stream->dev->lock); - usb_autopm_put_interface(stream->dev->intf); + /* + * If the uvc evdev exists we cannot suspend when the device + * is idle. Otherwise we will miss button actions. + */ + if (stream->dev->input) { + int ret; + + ret = uvc_pm_get(stream); + if (ret) { kfree(handle); return ret; } } - stream->dev->users++; - mutex_unlock(&stream->dev->lock); - v4l2_fh_init(&handle->vfh, &stream->vdev); v4l2_fh_add(&handle->vfh); handle->chain = stream->chain; @@ -610,6 +653,12 @@ static int uvc_v4l2_release(struct file *file) if (uvc_has_privileges(handle)) uvc_queue_release(&stream->queue); + if (handle->is_streaming) + uvc_pm_put(stream); + + if (stream->dev->input) + uvc_pm_put(stream); + /* Release the file handle. */ uvc_dismiss_privileges(handle); v4l2_fh_del(&handle->vfh); @@ -617,12 +666,6 @@ static int uvc_v4l2_release(struct file *file) kfree(handle); file->private_data = NULL; - mutex_lock(&stream->dev->lock); - if (--stream->dev->users == 0) - uvc_status_stop(stream->dev); - mutex_unlock(&stream->dev->lock); - - usb_autopm_put_interface(stream->dev->intf); return 0; } @@ -849,9 +892,17 @@ static int uvc_ioctl_streamon(struct file *file, void *fh, if (handle->is_streaming) goto unlock; + + ret = uvc_pm_get(stream); + if (ret) + goto unlock; + ret = uvc_queue_streamon(&stream->queue, type); handle->is_streaming = !ret; + if (!handle->is_streaming) + uvc_pm_put(stream); + unlock: mutex_unlock(&stream->mutex); @@ -875,6 +926,9 @@ static int uvc_ioctl_streamoff(struct file *file, void *fh, ret = uvc_queue_streamoff(&stream->queue, type); handle->is_streaming = !!ret; + if (!handle->is_streaming) + uvc_pm_put(stream); + unlock: mutex_unlock(&stream->mutex); @@ -928,6 +982,7 @@ static int uvc_ioctl_g_input(struct file *file, void *fh, unsigned int *input) { struct uvc_fh *handle = fh; struct uvc_video_chain *chain = handle->chain; + struct uvc_streaming *stream = handle->stream; u8 *buf; int ret; @@ -941,9 +996,16 @@ static int uvc_ioctl_g_input(struct file *file, void *fh, unsigned int *input) if (!buf) return -ENOMEM; + ret = uvc_pm_get(stream); + if (ret) { + kfree(buf); + return ret; + } + ret = uvc_query_ctrl(chain->dev, UVC_GET_CUR, chain->selector->id, chain->dev->intfnum, UVC_SU_INPUT_SELECT_CONTROL, buf, 1); + uvc_pm_put(stream); if (!ret) *input = *buf - 1; @@ -956,6 +1018,7 @@ static int uvc_ioctl_s_input(struct file *file, void *fh, unsigned int input) { struct uvc_fh *handle = fh; struct uvc_video_chain *chain = handle->chain; + struct uvc_streaming *stream = handle->stream; u8 *buf; int ret; @@ -977,10 +1040,17 @@ static int uvc_ioctl_s_input(struct file *file, void *fh, unsigned int input) if (!buf) return -ENOMEM; + ret = uvc_pm_get(stream); + if (ret) { + kfree(buf); + return ret; + } + *buf = input + 1; ret = uvc_query_ctrl(chain->dev, UVC_SET_CUR, chain->selector->id, chain->dev->intfnum, UVC_SU_INPUT_SELECT_CONTROL, buf, 1); + uvc_pm_put(stream); kfree(buf); return ret; @@ -991,8 +1061,15 @@ static int uvc_ioctl_queryctrl(struct file *file, void *fh, { struct uvc_fh *handle = fh; struct uvc_video_chain *chain = handle->chain; + struct uvc_streaming *stream = handle->stream; + int ret; - return uvc_query_v4l2_ctrl(chain, qc); + ret = uvc_pm_get(stream); + if (ret) + return ret; + ret = uvc_query_v4l2_ctrl(chain, qc); + uvc_pm_put(stream); + return ret; } static int uvc_ioctl_query_ext_ctrl(struct file *file, void *fh, @@ -1000,10 +1077,15 @@ static int uvc_ioctl_query_ext_ctrl(struct file *file, void *fh, { struct uvc_fh *handle = fh; struct uvc_video_chain *chain = handle->chain; + struct uvc_streaming *stream = handle->stream; struct v4l2_queryctrl qc = { qec->id }; int ret; + ret = uvc_pm_get(stream); + if (ret) + return ret; ret = uvc_query_v4l2_ctrl(chain, &qc); + uvc_pm_put(stream); if (ret) return ret; @@ -1049,6 +1131,7 @@ static int uvc_ioctl_g_ext_ctrls(struct file *file, void *fh, { struct uvc_fh *handle = fh; struct uvc_video_chain *chain = handle->chain; + struct uvc_streaming *stream = handle->stream; struct v4l2_ext_control *ctrl = ctrls->controls; unsigned int i; int ret; @@ -1073,22 +1156,30 @@ static int uvc_ioctl_g_ext_ctrls(struct file *file, void *fh, return 0; } + ret = uvc_pm_get(stream); + if (ret) + return ret; ret = uvc_ctrl_begin(chain); - if (ret < 0) + if (ret < 0) { + uvc_pm_put(stream); return ret; + } for (i = 0; i < ctrls->count; ++ctrl, ++i) { ret = uvc_ctrl_get(chain, ctrl); if (ret < 0) { uvc_ctrl_rollback(handle); ctrls->error_idx = i; - return ret; + goto done; } } ctrls->error_idx = 0; - return uvc_ctrl_rollback(handle); + ret = uvc_ctrl_rollback(handle); +done: + uvc_pm_put(stream); + return ret; } static int uvc_ioctl_s_try_ext_ctrls(struct uvc_fh *handle, @@ -1097,6 +1188,7 @@ static int uvc_ioctl_s_try_ext_ctrls(struct uvc_fh *handle, { struct v4l2_ext_control *ctrl = ctrls->controls; struct uvc_video_chain *chain = handle->chain; + struct uvc_streaming *stream = handle->stream; unsigned int i; int ret; @@ -1104,9 +1196,15 @@ static int uvc_ioctl_s_try_ext_ctrls(struct uvc_fh *handle, if (ret < 0) return ret; + ret = uvc_pm_get(stream); + if (ret) + return ret; + ret = uvc_ctrl_begin(chain); - if (ret < 0) + if (ret < 0) { + uvc_pm_put(stream); return ret; + } for (i = 0; i < ctrls->count; ++ctrl, ++i) { ret = uvc_ctrl_set(handle, ctrl); @@ -1114,16 +1212,20 @@ static int uvc_ioctl_s_try_ext_ctrls(struct uvc_fh *handle, uvc_ctrl_rollback(handle); ctrls->error_idx = ioctl == VIDIOC_S_EXT_CTRLS ? ctrls->count : i; - return ret; + goto done; } } ctrls->error_idx = 0; if (ioctl == VIDIOC_S_EXT_CTRLS) - return uvc_ctrl_commit(handle, ctrls); + ret = uvc_ctrl_commit(handle, ctrls); else - return uvc_ctrl_rollback(handle); + ret = uvc_ctrl_rollback(handle); + +done: + uvc_pm_put(stream); + return ret; } static int uvc_ioctl_s_ext_ctrls(struct file *file, void *fh, @@ -1147,8 +1249,16 @@ static int uvc_ioctl_querymenu(struct file *file, void *fh, { struct uvc_fh *handle = fh; struct uvc_video_chain *chain = handle->chain; + struct uvc_streaming *stream = handle->stream; + int ret; + + ret = uvc_pm_get(stream); + if (ret) + return ret; + ret = uvc_query_v4l2_menu(chain, qm); + uvc_pm_put(stream); - return uvc_query_v4l2_menu(chain, qm); + return ret; } static int uvc_ioctl_g_selection(struct file *file, void *fh, -- b4 0.11.0-dev-d93f8