Hi Niklas, On 5/17/19 10:07 PM, Niklas Söderlund wrote: > Prepare for multiple video streams from the same sensor by adding a use > counter to each subdevice. The counter is increase for every s_stream(1) > and decremented for every s_stream(0) call. > > The subdevice stream is not started or stopped unless the usage count go > from 0 to 1 (started) or from 1 to 0 (stopped). This allow for multiple > s_stream() calls to try to either start or stop the device while only > the first/last call will actually effect the state of the device. > > Signed-off-by: Niklas Söderlund <niklas.soderlund@xxxxxxxxxxxx> This patch won't be required if the following series gets accepted https://patchwork.linuxtv.org/cover/62233/ Since helpers takes care that s_stream(true) won't be called twice without s_stream(false) (and the opposite is also true). Regards, Helen > --- > drivers/media/platform/vimc/vimc-debayer.c | 8 ++++++++ > drivers/media/platform/vimc/vimc-scaler.c | 8 ++++++++ > drivers/media/platform/vimc/vimc-sensor.c | 7 +++++++ > 3 files changed, 23 insertions(+) > > diff --git a/drivers/media/platform/vimc/vimc-debayer.c b/drivers/media/platform/vimc/vimc-debayer.c > index 281f9c1a7249ad1d..624fc23ce3077d40 100644 > --- a/drivers/media/platform/vimc/vimc-debayer.c > +++ b/drivers/media/platform/vimc/vimc-debayer.c > @@ -56,6 +56,7 @@ struct vimc_deb_device { > struct vimc_ent_device ved; > struct v4l2_subdev sd; > struct device *dev; > + atomic_t use_count; > /* The active format */ > struct v4l2_mbus_framefmt sink_fmt; > u32 src_code; > @@ -337,6 +338,9 @@ static int vimc_deb_s_stream(struct v4l2_subdev *sd, int enable) > const struct v4l2_format_info *pix_info; > unsigned int frame_size; > > + if (atomic_inc_return(&vdeb->use_count) != 1) > + return 0; > + > if (vdeb->src_frame) > return 0; > > @@ -374,6 +378,9 @@ static int vimc_deb_s_stream(struct v4l2_subdev *sd, int enable) > return -ENOMEM; > > } else { > + if (atomic_dec_return(&vdeb->use_count) != 0) > + return 0; > + > if (!vdeb->src_frame) > return 0; > > @@ -562,6 +569,7 @@ static int vimc_deb_comp_bind(struct device *comp, struct device *master, > vdeb->ved.process_frame = vimc_deb_process_frame; > dev_set_drvdata(comp, &vdeb->ved); > vdeb->dev = comp; > + atomic_set(&vdeb->use_count, 0); > > /* Initialize the frame format */ > vdeb->sink_fmt = sink_fmt_default; > diff --git a/drivers/media/platform/vimc/vimc-scaler.c b/drivers/media/platform/vimc/vimc-scaler.c > index 8aecf8e920310608..37d2020d987a7d80 100644 > --- a/drivers/media/platform/vimc/vimc-scaler.c > +++ b/drivers/media/platform/vimc/vimc-scaler.c > @@ -45,6 +45,7 @@ struct vimc_sca_device { > struct vimc_ent_device ved; > struct v4l2_subdev sd; > struct device *dev; > + atomic_t use_count; > /* NOTE: the source fmt is the same as the sink > * with the width and hight multiplied by mult > */ > @@ -213,6 +214,9 @@ static int vimc_sca_s_stream(struct v4l2_subdev *sd, int enable) > const struct v4l2_format_info *pix_info; > unsigned int frame_size; > > + if (atomic_inc_return(&vsca->use_count) != 1) > + return 0; > + > if (vsca->src_frame) > return 0; > > @@ -242,6 +246,9 @@ static int vimc_sca_s_stream(struct v4l2_subdev *sd, int enable) > return -ENOMEM; > > } else { > + if (atomic_dec_return(&vsca->use_count) != 0) > + return 0; > + > if (!vsca->src_frame) > return 0; > > @@ -396,6 +403,7 @@ static int vimc_sca_comp_bind(struct device *comp, struct device *master, > vsca->ved.process_frame = vimc_sca_process_frame; > dev_set_drvdata(comp, &vsca->ved); > vsca->dev = comp; > + atomic_set(&vsca->use_count, 0); > > /* Initialize the frame format */ > vsca->sink_fmt = sink_fmt_default; > diff --git a/drivers/media/platform/vimc/vimc-sensor.c b/drivers/media/platform/vimc/vimc-sensor.c > index baca9ca67ce0af0b..36c3cea85a185f4b 100644 > --- a/drivers/media/platform/vimc/vimc-sensor.c > +++ b/drivers/media/platform/vimc/vimc-sensor.c > @@ -34,6 +34,7 @@ struct vimc_sen_device { > struct vimc_ent_device ved; > struct v4l2_subdev sd; > struct device *dev; > + atomic_t use_count; > struct tpg_data tpg; > struct task_struct *kthread_sen; > u8 *frame; > @@ -197,6 +198,9 @@ static int vimc_sen_s_stream(struct v4l2_subdev *sd, int enable) > const struct v4l2_format_info *pix_info; > unsigned int frame_size; > > + if (atomic_inc_return(&vsen->use_count) != 1) > + return 0; > + > if (vsen->kthread_sen) > /* tpg is already executing */ > return 0; > @@ -218,6 +222,8 @@ static int vimc_sen_s_stream(struct v4l2_subdev *sd, int enable) > vimc_sen_tpg_s_format(vsen); > > } else { > + if (atomic_dec_return(&vsen->use_count) != 0) > + return 0; > > vfree(vsen->frame); > vsen->frame = NULL; > @@ -367,6 +373,7 @@ static int vimc_sen_comp_bind(struct device *comp, struct device *master, > vsen->ved.process_frame = vimc_sen_process_frame; > dev_set_drvdata(comp, &vsen->ved); > vsen->dev = comp; > + atomic_set(&vsen->use_count, 0); > > /* Initialize the frame format */ > vsen->mbus_format = fmt_default; >
