Re: [PATCH 3/4] staging: vc04_services: avoid the use of typedef for function pointers

[Gaston Gonzalez <gascoar@gmail.com>]

On Tue, Dec 21, 2021 at 07:22:05AM +0100, Greg KH wrote:
> On Mon, Dec 20, 2021 at 06:29:13PM -0300, Gaston Gonzalez wrote:
> > Replace the function pointer typedef vchiq_mmal_buffer_cb with
> > equivalent declaration to better align with the linux kernel coding
> > style.
> > 
> > While at it, realignments were done in some touched lines.
> > 
> > Signed-off-by: Gaston Gonzalez <gascoar@gmail.com>
> > ---
> >  .../vc04_services/vchiq-mmal/mmal-vchiq.c     | 24 +++++++++----------
> >  .../vc04_services/vchiq-mmal/mmal-vchiq.h     | 13 +++++-----
> >  2 files changed, 18 insertions(+), 19 deletions(-)
> 
> Same subject line as patch 1/4 :(
> 
> > 
> > diff --git a/drivers/staging/vc04_services/vchiq-mmal/mmal-vchiq.c b/drivers/staging/vc04_services/vchiq-mmal/mmal-vchiq.c
> > index 76d3f0399964..54e5ce245ae7 100644
> > --- a/drivers/staging/vc04_services/vchiq-mmal/mmal-vchiq.c
> > +++ b/drivers/staging/vc04_services/vchiq-mmal/mmal-vchiq.c
> > @@ -269,10 +269,10 @@ static void buffer_work_cb(struct work_struct *work)
> >  
> >  	atomic_dec(&msg_context->u.bulk.port->buffers_with_vpu);
> >  
> > -	msg_context->u.bulk.port->buffer_cb(msg_context->u.bulk.instance,
> > -					    msg_context->u.bulk.port,
> > -					    msg_context->u.bulk.status,
> > -					    msg_context->u.bulk.buffer);
> > +	msg_context->u.bulk.port->vchiq_mmal_buffer_cb(msg_context->u.bulk.instance,
> > +						       msg_context->u.bulk.port,
> > +						       msg_context->u.bulk.status,
> > +						       msg_context->u.bulk.buffer);
> >  }
> >  
> >  /* workqueue scheduled callback to handle receiving buffers
> > @@ -1327,13 +1327,12 @@ static int port_disable(struct vchiq_mmal_instance *instance,
> >  			mmalbuf = list_entry(buf_head, struct mmal_buffer,
> >  					     list);
> >  			list_del(buf_head);
> > -			if (port->buffer_cb) {
> > +			if (port->vchiq_mmal_buffer_cb) {
> >  				mmalbuf->length = 0;
> >  				mmalbuf->mmal_flags = 0;
> >  				mmalbuf->dts = MMAL_TIME_UNKNOWN;
> >  				mmalbuf->pts = MMAL_TIME_UNKNOWN;
> > -				port->buffer_cb(instance,
> > -						port, 0, mmalbuf);
> > +				port->vchiq_mmal_buffer_cb(instance, port, 0, mmalbuf);
> >  			}
> >  		}
> >  
> > @@ -1363,7 +1362,7 @@ static int port_enable(struct vchiq_mmal_instance *instance,
> >  
> >  	port->enabled = 1;
> >  
> > -	if (port->buffer_cb) {
> > +	if (port->vchiq_mmal_buffer_cb) {
> >  		/* send buffer headers to videocore */
> >  		hdr_count = 1;
> >  		list_for_each_safe(buf_head, q, &port->buffers) {
> > @@ -1454,9 +1453,10 @@ EXPORT_SYMBOL_GPL(vchiq_mmal_port_parameter_get);
> >   * enables a port and queues buffers for satisfying callbacks if we
> >   * provide a callback handler
> >   */
> > -int vchiq_mmal_port_enable(struct vchiq_mmal_instance *instance,
> > -			   struct vchiq_mmal_port *port,
> > -			   vchiq_mmal_buffer_cb buffer_cb)
> > +int vchiq_mmal_port_enable(struct vchiq_mmal_instance *instance, struct vchiq_mmal_port *port,
> > +			   void (*vchiq_mmal_buffer_cb)(struct vchiq_mmal_instance  *instance,
> > +							struct vchiq_mmal_port *port, int status,
> > +							struct mmal_buffer *buffer))
> >  {
> >  	int ret;
> >  
> > @@ -1469,7 +1469,7 @@ int vchiq_mmal_port_enable(struct vchiq_mmal_instance *instance,
> >  		goto unlock;
> >  	}
> >  
> > -	port->buffer_cb = buffer_cb;
> > +	port->vchiq_mmal_buffer_cb = vchiq_mmal_buffer_cb;
> >  
> >  	ret = port_enable(instance, port);
> >  
> > diff --git a/drivers/staging/vc04_services/vchiq-mmal/mmal-vchiq.h b/drivers/staging/vc04_services/vchiq-mmal/mmal-vchiq.h
> > index 1dc81ecf9268..39615ce6584a 100644
> > --- a/drivers/staging/vc04_services/vchiq-mmal/mmal-vchiq.h
> > +++ b/drivers/staging/vc04_services/vchiq-mmal/mmal-vchiq.h
> > @@ -42,11 +42,6 @@ struct vchiq_mmal_port_buffer {
> >  
> >  struct vchiq_mmal_port;
> >  
> > -typedef void (*vchiq_mmal_buffer_cb)(
> > -		struct vchiq_mmal_instance  *instance,
> > -		struct vchiq_mmal_port *port,
> > -		int status, struct mmal_buffer *buffer);
> > -
> >  struct vchiq_mmal_port {
> >  	u32 enabled:1;
> >  	u32 handle;
> > @@ -76,7 +71,9 @@ struct vchiq_mmal_port {
> >  	/* Count of buffers the VPU has yet to return */
> >  	atomic_t buffers_with_vpu;
> >  	/* callback on buffer completion */
> > -	vchiq_mmal_buffer_cb buffer_cb;
> > +	void (*vchiq_mmal_buffer_cb)(struct vchiq_mmal_instance  *instance,
> > +				     struct vchiq_mmal_port *port, int status,
> > +				     struct mmal_buffer *buffer);
> 
> There is no need to rename the function pointer at all.
> 
> >  	/* callback context */
> >  	void *cb_ctx;
> >  };
> > @@ -126,7 +123,9 @@ int vchiq_mmal_component_disable(
> >  int vchiq_mmal_port_enable(
> >  		struct vchiq_mmal_instance *instance,
> >  		struct vchiq_mmal_port *port,
> > -		vchiq_mmal_buffer_cb buffer_cb);
> > +		void (*vchiq_mmal_buffer_cb)(struct vchiq_mmal_instance  *instance,
> > +					     struct vchiq_mmal_port *port, int status,
> > +					     struct mmal_buffer *buffer));
> >  
> 
> Here is where using a typedef is ok.  Again, typedefs for function
> pointers is normal and keeps code smaller and easier to follow.
>

Ok, I had my doubts about this one just because that lines.

Will drop it.

thanks,

Gaston


> thanks,
> 
> greg k-h