Hi Laurent,
Thanks a lot for the thorough review.
On Thu, 2021-01-14 at 04:06 +0200, Laurent Pinchart wrote:
> Hi Ezequiel,
>
> Thank you for the patch.
>
> On Tue, Jan 12, 2021 at 10:23:29AM -0300, Ezequiel Garcia wrote:
> > The use of v4l2_async_notifier_add_subdev is discouraged.
>
> It's not yet, that only happens at the end of the series :-)
>
> s/is discouraged/will be discouraged/
>
Makes sense. Will change this on all the commits.
> > Drivers are instead encouraged to use a helper such as
> > v4l2_async_notifier_add_i2c_subdev.
> >
> > This fixes a misuse of the API, as v4l2_async_notifier_add_subdev
> > should get a kmalloc'ed struct v4l2_async_subdev,
> > removing some boilerplate code while at it.
> >
> > Use the appropriate helper: v4l2_async_notifier_add_i2c_subdev
> > or v4l2_async_notifier_add_fwnode_remote_subdev, which handles
> > the needed setup, instead of open-coding it.
> >
> > Using v4l2-async to allocate the driver-specific structs,
> > requires to change struct ceu_subdev so the embedded
> > struct v4l2_async_subdev is now the first element.
> >
> > Signed-off-by: Ezequiel Garcia <ezequiel@xxxxxxxxxxxxx>
> > ---
> > drivers/media/platform/renesas-ceu.c | 89 ++++++++++------------------
> > 1 file changed, 31 insertions(+), 58 deletions(-)
> >
> > diff --git a/drivers/media/platform/renesas-ceu.c b/drivers/media/platform/renesas-ceu.c
> > index 4a633ad0e8fa..18485812a21e 100644
> > --- a/drivers/media/platform/renesas-ceu.c
> > +++ b/drivers/media/platform/renesas-ceu.c
> > @@ -152,8 +152,8 @@ static inline struct ceu_buffer *vb2_to_ceu(struct vb2_v4l2_buffer *vbuf)
> > * ceu_subdev - Wraps v4l2 sub-device and provides async subdevice.
> > */
> > struct ceu_subdev {
> > - struct v4l2_subdev *v4l2_sd;
> > struct v4l2_async_subdev asd;
> > + struct v4l2_subdev *v4l2_sd;
> >
> > /* per-subdevice mbus configuration options */
> > unsigned int mbus_flags;
> > @@ -174,7 +174,7 @@ struct ceu_device {
> > struct v4l2_device v4l2_dev;
> >
> > /* subdevices descriptors */
> > - struct ceu_subdev *subdevs;
> > + struct ceu_subdev **subdevs;
> > /* the subdevice currently in use */
> > struct ceu_subdev *sd;
> > unsigned int sd_index;
> > @@ -1195,7 +1195,7 @@ static int ceu_enum_input(struct file *file, void *priv,
> > if (inp->index >= ceudev->num_sd)
> > return -EINVAL;
> >
> > - ceusd = &ceudev->subdevs[inp->index];
> > + ceusd = ceudev->subdevs[inp->index];
> >
> > inp->type = V4L2_INPUT_TYPE_CAMERA;
> > inp->std = 0;
> > @@ -1230,7 +1230,7 @@ static int ceu_s_input(struct file *file, void *priv, unsigned int i)
> > return 0;
> >
> > ceu_sd_old = ceudev->sd;
> > - ceudev->sd = &ceudev->subdevs[i];
> > + ceudev->sd = ceudev->subdevs[i];
> >
> > /*
> > * Make sure we can generate output image formats and apply
> > @@ -1423,7 +1423,7 @@ static int ceu_notify_complete(struct v4l2_async_notifier *notifier)
> > * ceu formats.
> > */
> > if (!ceudev->sd) {
> > - ceudev->sd = &ceudev->subdevs[0];
> > + ceudev->sd = ceudev->subdevs[0];
> > ceudev->sd_index = 0;
> > }
> >
> > @@ -1465,28 +1465,6 @@ static const struct v4l2_async_notifier_operations ceu_notify_ops = {
> > .complete = ceu_notify_complete,
> > };
> >
> > -/*
> > - * ceu_init_async_subdevs() - Initialize CEU subdevices and async_subdevs in
> > - * ceu device. Both DT and platform data parsing use
> > - * this routine.
> > - *
> > - * Returns 0 for success, -ENOMEM for failure.
> > - */
> > -static int ceu_init_async_subdevs(struct ceu_device *ceudev, unsigned int n_sd)
> > -{
> > - /* Reserve memory for 'n_sd' ceu_subdev descriptors. */
> > - ceudev->subdevs = devm_kcalloc(ceudev->dev, n_sd,
> > - sizeof(*ceudev->subdevs), GFP_KERNEL);
>
> I may be missing something, but it looks like the subdevs array isn't
> allocated anymore. It turned to an array of pointers, but it still need
> allocation.
>
Oops. Thanks for spotting this.
> > - if (!ceudev->subdevs)
> > - return -ENOMEM;
> > -
> > - ceudev->sd = NULL;
> > - ceudev->sd_index = 0;
> > - ceudev->num_sd = 0;
> > -
> > - return 0;
> > -}
> > -
> > /*
> > * ceu_parse_platform_data() - Initialize async_subdevices using platform
> > * device provided data.
> > @@ -1495,6 +1473,7 @@ static int ceu_parse_platform_data(struct ceu_device *ceudev,
> > const struct ceu_platform_data *pdata)
> > {
> > const struct ceu_async_subdev *async_sd;
> > + struct v4l2_async_subdev *asd;
> > struct ceu_subdev *ceu_sd;
> > unsigned int i;
> > int ret;
> > @@ -1502,29 +1481,26 @@ static int ceu_parse_platform_data(struct ceu_device *ceudev,
> > if (pdata->num_subdevs == 0)
> > return -ENODEV;
> >
> > - ret = ceu_init_async_subdevs(ceudev, pdata->num_subdevs);
> > - if (ret)
> > - return ret;
> > + ceudev->sd = NULL;
> > + ceudev->sd_index = 0;
> > + ceudev->num_sd = 0;
>
> ceudev is kzalloc()ed, so I think you could skip this.
>
Right.
> >
> > for (i = 0; i < pdata->num_subdevs; i++) {
> >
> > /* Setup the ceu subdevice and the async subdevice. */
> > async_sd = &pdata->subdevs[i];
> > - ceu_sd = &ceudev->subdevs[i];
> > -
> > - INIT_LIST_HEAD(&ceu_sd->asd.list);
> > -
> > - ceu_sd->mbus_flags = async_sd->flags;
> > - ceu_sd->asd.match_type = V4L2_ASYNC_MATCH_I2C;
> > - ceu_sd->asd.match.i2c.adapter_id = async_sd->i2c_adapter_id;
> > - ceu_sd->asd.match.i2c.address = async_sd->i2c_address;
> > -
> > - ret = v4l2_async_notifier_add_subdev(&ceudev->notifier,
> > - &ceu_sd->asd);
> > - if (ret) {
> > + asd = v4l2_async_notifier_add_i2c_subdev(&ceudev->notifier,
> > + async_sd->i2c_adapter_id,
> > + async_sd->i2c_address,
> > + sizeof(*ceu_sd));
> > + if (IS_ERR(asd)) {
> > + ret = PTR_ERR(asd);
> > v4l2_async_notifier_cleanup(&ceudev->notifier);
> > return ret;
> > }
> > + ceu_sd = to_ceu_subdev(asd);
> > + ceu_sd->mbus_flags = async_sd->flags;
> > + ceudev->subdevs[i] = ceu_sd;
> > }
> >
> > return pdata->num_subdevs;
> > @@ -1536,7 +1512,8 @@ static int ceu_parse_platform_data(struct ceu_device *ceudev,
> > static int ceu_parse_dt(struct ceu_device *ceudev)
> > {
> > struct device_node *of = ceudev->dev->of_node;
> > - struct device_node *ep, *remote;
> > + struct device_node *ep;
> > + struct v4l2_async_subdev *asd;
> > struct ceu_subdev *ceu_sd;
> > unsigned int i;
> > int num_ep;
> > @@ -1546,9 +1523,9 @@ static int ceu_parse_dt(struct ceu_device *ceudev)
> > if (!num_ep)
> > return -ENODEV;
> >
> > - ret = ceu_init_async_subdevs(ceudev, num_ep);
> > - if (ret)
> > - return ret;
> > + ceudev->sd = NULL;
> > + ceudev->sd_index = 0;
> > + ceudev->num_sd = 0;
>
> Same here, I think this could be skipped.
>
Yup.
Thanks,
Ezequiel
