Re: [PATCH] misc: fastrpc: add ioctl for attaching to sensors pd

[Jonathan Marek]

On 9/7/20 8:33 AM, Greg Kroah-Hartman wrote:
> On Mon, Aug 31, 2020 at 08:32:59PM -0400, Jonathan Marek wrote:
> > Initializing sensors requires attaching to pd 2. Add an ioctl for that.
> >
> > This corresponds to FASTRPC_INIT_ATTACH_SENSORS in the downstream driver.
> >
> > Signed-off-by: Jonathan Marek <jonathan@xxxxxxxx>
> > ---
> >   drivers/misc/fastrpc.c      | 9 ++++++---
> >   include/uapi/misc/fastrpc.h | 5 +++--
> >   2 files changed, 9 insertions(+), 5 deletions(-)
> >
> > diff --git a/drivers/misc/fastrpc.c b/drivers/misc/fastrpc.c
> > index 7939c55daceb..ea5e9ca0d705 100644
> > --- a/drivers/misc/fastrpc.c
> > +++ b/drivers/misc/fastrpc.c
> > @@ -1276,7 +1276,7 @@ static int fastrpc_dmabuf_alloc(struct fastrpc_user *fl, char __user *argp)
> >   	return 0;
> >   }
> >   
> > -static int fastrpc_init_attach(struct fastrpc_user *fl)
> > +static int fastrpc_init_attach(struct fastrpc_user *fl, int pd)
> >   {
> >   	struct fastrpc_invoke_args args[1];
> >   	int tgid = fl->tgid;
> > @@ -1287,7 +1287,7 @@ static int fastrpc_init_attach(struct fastrpc_user *fl)
> >   	args[0].fd = -1;
> >   	args[0].reserved = 0;
> >   	sc = FASTRPC_SCALARS(FASTRPC_RMID_INIT_ATTACH, 1, 0);
> > -	fl->pd = 0;
> > +	fl->pd = pd;
> >   
> >   	return fastrpc_internal_invoke(fl, true, FASTRPC_INIT_HANDLE,
> >   				       sc, &args[0]);
> > @@ -1477,7 +1477,10 @@ static long fastrpc_device_ioctl(struct file *file, unsigned int cmd,
> >   		err = fastrpc_invoke(fl, argp);
> >   		break;
> >   	case FASTRPC_IOCTL_INIT_ATTACH:
> > -		err = fastrpc_init_attach(fl);
> > +		err = fastrpc_init_attach(fl, 0);
> > +		break;
> > +	case FASTRPC_IOCTL_INIT_ATTACH_SNS:
> > +		err = fastrpc_init_attach(fl, 2);
>
> Shouldn't you have #defines for those magic numbers somewhere?  What
> does 0 and 2 mean?

This is based off a downstream driver which also uses magic numbers, 
although I can make an educated guess about the meaning.

Srini do you have any suggestions for how to name these values?

> thanks,
>
> greg k-h