Re: [PATCH 3/4] media: renesas: Use state cleanup macros

Laurent Pinchart
2024-09-24T17:24:57Z

On Sun, Sep 22, 2024 at 12:15:19PM +0200, Niklas Söderlund wrote:
> Hi Tomi,
>
> Thanks for your work. I like the scoped management.
>
> On 2024-09-17 17:09:31 +0300, Tomi Valkeinen wrote:
> > From: Tomi Valkeinen <tomi.valkeinen+renesas@ideasonboard.com>
> >
> > Use the new subdev state cleanup macros.
> >
> > Signed-off-by: Tomi Valkeinen <tomi.valkeinen+renesas@ideasonboard.com>
> > ---
> > drivers/media/platform/renesas/rcar-csi2.c | 14 ++++----------
> > drivers/media/platform/renesas/rzg2l-cru/rzg2l-csi2.c | 9 ++++-----
> > drivers/media/platform/renesas/rzg2l-cru/rzg2l-ip.c | 9 ++-------
> > 3 files changed, 10 insertions(+), 22 deletions(-)
> >
> > diff --git a/drivers/media/platform/renesas/rcar-csi2.c b/drivers/media/platform/renesas/rcar-csi2.c
> > index c419ddb4c5a2..03ef6566271f 100644
> > --- a/drivers/media/platform/renesas/rcar-csi2.c
> > +++ b/drivers/media/platform/renesas/rcar-csi2.c
> > @@ -1163,27 +1163,24 @@ static void rcsi2_stop(struct rcar_csi2 *priv)
> > static int rcsi2_s_stream(struct v4l2_subdev *sd, int enable)
> > {
> > struct rcar_csi2 *priv = sd_to_csi2(sd);
> > - struct v4l2_subdev_state *state;
> > int ret = 0;
> >
> > if (!priv->remote)
> > return -ENODEV;
> >
> > - state = v4l2_subdev_lock_and_get_active_state(&priv->subdev);
> > + CLASS(v4l2_subdev_lock_and_get_active_state, state)(&priv->subdev);
> >
> > if (enable && priv->stream_count == 0) {
> > ret = rcsi2_start(priv, state);
> > if (ret)
> > - goto out;
> > + return ret;
>
> As ret is now only used in this branch maybe we can move the declaration
> of it here? At least I think you should remove the assignment to 0 above
> as that behavior is not needed anymore but, at lest to me, keeping it
> indicates there is an intent in initializing it.
>
> With that fixed,
>
> Reviewed-by: Niklas Söderlund <niklas.soderlund+renesas@ragnatech.se>
>
> > } else if (!enable && priv->stream_count == 1) {
> > rcsi2_stop(priv);
> > }
> >
> > priv->stream_count += enable ? 1 : -1;
> > -out:
> > - v4l2_subdev_unlock_state(state);
> >
> > - return ret;
> > + return 0;
> > }
> >
> > static int rcsi2_set_pad_format(struct v4l2_subdev *sd,
> > @@ -1274,18 +1271,15 @@ static irqreturn_t rcsi2_irq(int irq, void *data)
> >
> > static irqreturn_t rcsi2_irq_thread(int irq, void *data)
> > {
> > - struct v4l2_subdev_state *state;
> > struct rcar_csi2 *priv = data;
> >
> > - state = v4l2_subdev_lock_and_get_active_state(&priv->subdev);
> > + CLASS(v4l2_subdev_lock_and_get_active_state, state)(&priv->subdev);
> >
> > rcsi2_stop(priv);
> > usleep_range(1000, 2000);
> > if (rcsi2_start(priv, state))
> > dev_warn(priv->dev, "Failed to restart CSI-2 receiver\n");
> >
> > - v4l2_subdev_unlock_state(state);
> > -
> > return IRQ_HANDLED;
> > }
> >
> > diff --git a/drivers/media/platform/renesas/rzg2l-cru/rzg2l-csi2.c b/drivers/media/platform/renesas/rzg2l-cru/rzg2l-csi2.c
> > index e68fcdaea207..63b846f3e468 100644
> > --- a/drivers/media/platform/renesas/rzg2l-cru/rzg2l-csi2.c
> > +++ b/drivers/media/platform/renesas/rzg2l-cru/rzg2l-csi2.c
> > @@ -238,7 +238,6 @@ static int rzg2l_csi2_calc_mbps(struct rzg2l_csi2 *csi2)
> > struct v4l2_subdev *source = csi2->remote_source;
> > const struct rzg2l_csi2_format *format;
> > const struct v4l2_mbus_framefmt *fmt;
> > - struct v4l2_subdev_state *state;
> > struct v4l2_ctrl *ctrl;
> > u64 mbps;
> >
> > @@ -250,10 +249,10 @@ static int rzg2l_csi2_calc_mbps(struct rzg2l_csi2 *csi2)
> > return -EINVAL;
> > }
> >
> > - state = v4l2_subdev_lock_and_get_active_state(&csi2->subdev);
> > - fmt = v4l2_subdev_state_get_format(state, RZG2L_CSI2_SINK);
> > - format = rzg2l_csi2_code_to_fmt(fmt->code);
> > - v4l2_subdev_unlock_state(state);
> > + scoped_v4l2_subdev_lock_and_get_active_state(&csi2->subdev) {
> > + fmt = v4l2_subdev_state_get_format(state, RZG2L_CSI2_SINK);

fmt could also become a local variable.

Now that I'm looking at this, another issue with
scoped_v4l2_subdev_lock_and_get_active_state() is that it creates a
non-const state variable, while there are use cases for const states.
I'm increasingly thinking we should use __free(), as neither the
scoped_* macro nor CLASS() allow the caller to indicate if the local
variable should be const or not.

> > + format = rzg2l_csi2_code_to_fmt(fmt->code);
> > + }
> >
> > /*
> > * Calculate hsfreq in Mbps
> > diff --git a/drivers/media/platform/renesas/rzg2l-cru/rzg2l-ip.c b/drivers/media/platform/renesas/rzg2l-cru/rzg2l-ip.c
> > index ac8ebae4ed07..0b9e8a7cf22a 100644
> > --- a/drivers/media/platform/renesas/rzg2l-cru/rzg2l-ip.c
> > +++ b/drivers/media/platform/renesas/rzg2l-cru/rzg2l-ip.c
> > @@ -36,14 +36,9 @@ static const struct rzg2l_cru_ip_format *rzg2l_cru_ip_code_to_fmt(unsigned int c
> >
> > struct v4l2_mbus_framefmt *rzg2l_cru_ip_get_src_fmt(struct rzg2l_cru_dev *cru)
> > {
> > - struct v4l2_subdev_state *state;
> > - struct v4l2_mbus_framefmt *fmt;
> > + CLASS(v4l2_subdev_lock_and_get_active_state, state)(&cru->ip.subdev);
> >
> > - state = v4l2_subdev_lock_and_get_active_state(&cru->ip.subdev);
> > - fmt = v4l2_subdev_state_get_format(state, 1);
> > - v4l2_subdev_unlock_state(state);
> > -
> > - return fmt;
> > + return v4l2_subdev_state_get_format(state, 1);
> > }
> >
> > static int rzg2l_cru_ip_s_stream(struct v4l2_subdev *sd, int enable)
> >

--
Regards,

Laurent Pinchart