PCMCIA insert on resume

PCMCIA insert on resume

[Rodolfo Giometti]

Hello,

I don't understand why, on resume, the function socket_resume() (in
drivers/pcmcia/cs.c) do:

       if (!(skt->state & SOCKET_PRESENT)) {
               skt->state &= ~SOCKET_SUSPEND;
               return socket_insert(skt);
       }

This cause a powered off socket before suspend to be powered on during
resume.

To avoid such (erroneous?) behaviour I propose this patch:

diff --git a/drivers/pcmcia/cs.c b/drivers/pcmcia/cs.c
index 729e37d..d69de74 100644
--- a/drivers/pcmcia/cs.c
+++ b/drivers/pcmcia/cs.c
@@ -562,10 +562,8 @@ static int socket_resume(struct pcmcia_socket *skt)
        skt->ops->init(skt);
        skt->ops->set_socket(skt, &skt->socket);
 
-       if (!(skt->state & SOCKET_PRESENT)) {
-               skt->state &= ~SOCKET_SUSPEND;
-               return socket_insert(skt);
-       }
+       if (!(skt->state & SOCKET_PRESENT))
+               goto resume_exit;
 
        ret = socket_setup(skt, SS_COMA, resume_delay);
        if (ret == CS_SUCCESS) {
@@ -599,6 +597,7 @@ static int socket_resume(struct pcmcia_socket *skt)
                socket_shutdown(skt);
        }
 
+resume_exit:
        skt->state &= ~SOCKET_SUSPEND;
 
        return CS_SUCCESS;

With this patch if the socket was powered down before the suspend, at
resume time it's not powered on and you need a "pccardctl insert" to
activate the socket.

Ciao,

Rodolfo

-- 

GNU/Linux Solutions                  e-mail:    giometti@enneenne.com
Linux Device Driver                             giometti@gnudd.com
Embedded Systems                     		giometti@linux.it
UNIX programming                     phone:     +39 349 2432127

Re: PCMCIA insert on resume

[Pavel Machek]

Hi!

> I don't understand why, on resume, the function socket_resume() (in
> drivers/pcmcia/cs.c) do:
> 
>        if (!(skt->state & SOCKET_PRESENT)) {
>                skt->state &= ~SOCKET_SUSPEND;
>                return socket_insert(skt);
>        }
> 
> This cause a powered off socket before suspend to be powered on during
> resume.
> 
> To avoid such (erroneous?) behaviour I propose this patch:
> 
> diff --git a/drivers/pcmcia/cs.c b/drivers/pcmcia/cs.c
> index 729e37d..d69de74 100644
> --- a/drivers/pcmcia/cs.c
> +++ b/drivers/pcmcia/cs.c
> @@ -562,10 +562,8 @@ static int socket_resume(struct pcmcia_socket *skt)
>         skt->ops->init(skt);
>         skt->ops->set_socket(skt, &skt->socket);
>  
> -       if (!(skt->state & SOCKET_PRESENT)) {
> -               skt->state &= ~SOCKET_SUSPEND;
> -               return socket_insert(skt);
> -       }
> +       if (!(skt->state & SOCKET_PRESENT))
> +               goto resume_exit;
>  
>         ret = socket_setup(skt, SS_COMA, resume_delay);
>         if (ret == CS_SUCCESS) {
> @@ -599,6 +597,7 @@ static int socket_resume(struct pcmcia_socket *skt)
>                 socket_shutdown(skt);
>         }
>  
> +resume_exit:
>         skt->state &= ~SOCKET_SUSPEND;
>  
>         return CS_SUCCESS;
> 
> With this patch if the socket was powered down before the suspend, at
> resume time it's not powered on and you need a "pccardctl insert" to
> activate the socket.

Seems okay to me, but I do not know much about pcmcia. Add
signed-off-by, changelog at the beggining, cc me, rafael and akpm... ?
							Pavel
-- 
(english) http://www.livejournal.com/~pavelmachek
(cesky, pictures) http://atrey.karlin.mff.cuni.cz/~pavel/picture/horses/blog.html

Re: PCMCIA insert on resume

[Rafael J. Wysocki]

On Saturday, 27 October 2007 09:45, Pavel Machek wrote:
> Hi!
> 
> > I don't understand why, on resume, the function socket_resume() (in
> > drivers/pcmcia/cs.c) do:
> > 
> >        if (!(skt->state & SOCKET_PRESENT)) {
> >                skt->state &= ~SOCKET_SUSPEND;
> >                return socket_insert(skt);
> >        }
> > 
> > This cause a powered off socket before suspend to be powered on during
> > resume.
> > 
> > To avoid such (erroneous?) behaviour I propose this patch:
> > 
> > diff --git a/drivers/pcmcia/cs.c b/drivers/pcmcia/cs.c
> > index 729e37d..d69de74 100644
> > --- a/drivers/pcmcia/cs.c
> > +++ b/drivers/pcmcia/cs.c
> > @@ -562,10 +562,8 @@ static int socket_resume(struct pcmcia_socket *skt)
> >         skt->ops->init(skt);
> >         skt->ops->set_socket(skt, &skt->socket);
> >  
> > -       if (!(skt->state & SOCKET_PRESENT)) {
> > -               skt->state &= ~SOCKET_SUSPEND;
> > -               return socket_insert(skt);
> > -       }
> > +       if (!(skt->state & SOCKET_PRESENT))
> > +               goto resume_exit;
> >  
> >         ret = socket_setup(skt, SS_COMA, resume_delay);
> >         if (ret == CS_SUCCESS) {
> > @@ -599,6 +597,7 @@ static int socket_resume(struct pcmcia_socket *skt)
> >                 socket_shutdown(skt);
> >         }
> >  
> > +resume_exit:
> >         skt->state &= ~SOCKET_SUSPEND;
> >  
> >         return CS_SUCCESS;
> > 
> > With this patch if the socket was powered down before the suspend, at
> > resume time it's not powered on and you need a "pccardctl insert" to
> > activate the socket.
> 
> Seems okay to me, but I do not know much about pcmcia. Add
> signed-off-by, changelog at the beggining, cc me, rafael and akpm... ?

Actually, there are some objections wrt this patch from Russell King.

Greetings,
Rafael