From: Adam Belay <ambx1@neo.rr.com>
On Mon, Jul 19, 2004 at 10:02:37AM +0200, Dominik Brodowski wrote:
> Hi Adam,
>
> On Mon, Jul 05, 2004 at 10:47:04PM +0000, Adam Belay wrote:
> > > - I like many ideas in your patches -- large parts of them, though, are
> > > "double work" as similar things have already been submitted (by me)
> > > to Russell on the linux-pcmcia mailing list. What's missing in my current
> > > patches [proof-of-concepts do exist and had been announced both on lkml
> > > and on said linux-pcmcia list, though] is the exporting of product and
> > > manufactor ID and "vers_1" strings, because that needs better resource
> > > handling.
> > > - the resource_ready handling is "racy", at least. Resources can disappear
> > > again.
> >
> > Could you provide an example of how resources will disappear again?
>
> /etc/pcmcia/config.opts may include
>
> include memory 0xc0000-0xfffff
> exclude memory 0xc0000-0xfffff
>
> even though it wouldn't make sense.
Hmm, ok.
> It is, but partly because used ioports and iomem are not 100% accounted in
> /proc/ioports and /proc/iomem. I'm eagerly awaiting the creation of a PNP-
> and/or ACPI-based resource core "backend", like you proposed at Kernel
> Summit last year, IIRC, which possibly allows the PCMCIA core on x86{,_64}
> to "trust" the resources not in the resource database to be available for
> PCMCIA's use.
I appreciate the interest. It's currently under development.
>
> > It was to add minimal support for a much needed feature while introducing
> > as few potential bugs as possible to a stable kernel series. I see 2.7 as
> > the time for rewrites. With that in mind, I consider your patches to be a
> > great solution, but I'm worried about changing internal ds functionality
> > during 2.6.
>
> However, adding pcmcia devices at the place you suggest causes resource
> headaches and makes merging my patches in 2.7. much more difficult. So,
> could we work to a compromise patch where PCMCIA sysfs device structs are
> only registered at "bind" time [as long as Russell agrees, that is...]?
>
> Also, what do we need the "hotplug" export for? I'd like to avoid backwards
> compatibility trouble in future, and as users _need_ to run cardmgr hotplug
> seems to be without usage now.
>
> Dominik
I agree that the current resources_ready flag could create potential problems.
I've created another patch against the previous three that removes its usage,
and relies entirely on DS_BIND_REQUEST. Devices are now removed but never
added during hardware events. As for "hotplug", I was just trying to create
a complete driver model implementation. I don't expect it to be used much now,
but it is an official driver model feature.
Signed-off-by: Andrew Morton <akpm@osdl.org>
---
25-akpm/drivers/pcmcia/ds.c | 37 +------------------------------------
1 files changed, 1 insertion(+), 36 deletions(-)
diff -puN drivers/pcmcia/ds.c~driver-model-and-sysfs-support-for-pcmcia-update drivers/pcmcia/ds.c
--- 25/drivers/pcmcia/ds.c~driver-model-and-sysfs-support-for-pcmcia-update 2004-07-26 22:23:58.985835960 -0700
+++ 25-akpm/drivers/pcmcia/ds.c 2004-07-26 22:23:58.990835200 -0700
@@ -108,9 +108,6 @@ typedef struct user_info_t {
struct pcmcia_bus_socket *socket;
} user_info_t;
-static LIST_HEAD(pcmcia_sockets);
-static DECLARE_MUTEX(pcmcia_socket_mutex);
-
/* Socket state information */
struct pcmcia_bus_socket {
atomic_t refcount;
@@ -124,7 +121,6 @@ struct pcmcia_bus_socket {
struct pcmcia_socket *parent;
struct list_head devices;
struct semaphore device_mutex;
- struct list_head socket_list;
};
#define DS_SOCKET_PRESENT 0x01
@@ -141,8 +137,6 @@ static int major_dev = -1;
extern struct proc_dir_entry *proc_pccard;
-static int resources_ready;
-
/*====================================================================*/
/* code which was in cs.c before */
@@ -521,9 +515,6 @@ static int pcmcia_bus_insert_card(struct
if (!(s->state & DS_SOCKET_PRESENT))
return CS_NO_CARD;
- if (!resources_ready && !(s->parent->features & SS_CAP_STATIC_MAP))
- return CS_NO_CARD;
-
down(&s->device_mutex);
if (!list_empty(&s->devices)) {
ret = -EBUSY;
@@ -639,18 +630,6 @@ int pcmcia_bus_hotplug(struct device *pd
#endif /* CONFIG_HOTPLUG */
-static void pcmcia_rescan_sockets(void)
-{
- struct pcmcia_bus_socket *s;
-
- down(&pcmcia_socket_mutex);
-
- list_for_each_entry(s, &pcmcia_sockets, socket_list)
- pcmcia_bus_insert_card(s);
-
- up(&pcmcia_socket_mutex);
-}
-
/*======================================================================
These manage a ring buffer of events pending for one user process
@@ -733,7 +712,6 @@ static int ds_event(event_t event, int p
case CS_EVENT_CARD_INSERTION:
s->state |= DS_SOCKET_PRESENT;
- pcmcia_bus_insert_card(s);
handle_event(s, event);
break;
@@ -1182,12 +1160,6 @@ static int ds_ioctl(struct inode * inode
switch (cmd) {
case DS_ADJUST_RESOURCE_INFO:
ret = pcmcia_adjust_resource_info(s->handle, &buf.adjust);
- /*
- * We can't read CIS information until user space has given us the
- * memory resource locations. Therefore, we wait until now.
- */
- if ((ret == CS_SUCCESS) && (buf.adjust.Resource == RES_MEMORY_RANGE))
- resources_ready = 1;
break;
case DS_GET_CARD_SERVICES_INFO:
ret = pcmcia_get_card_services_info(&buf.servinfo);
@@ -1260,7 +1232,7 @@ static int ds_ioctl(struct inode * inode
break;
case DS_BIND_REQUEST:
if (!capable(CAP_SYS_ADMIN)) return -EPERM;
- pcmcia_rescan_sockets();
+ pcmcia_bus_insert_card(s);
err = bind_request(s, &buf.bind_info);
break;
case DS_GET_DEVICE_INFO:
@@ -1332,10 +1304,6 @@ static int __devinit pcmcia_bus_add_sock
memset(s, 0, sizeof(struct pcmcia_bus_socket));
atomic_set(&s->refcount, 1);
- down(&pcmcia_socket_mutex);
- list_add_tail(&s->socket_list, &pcmcia_sockets);
- up(&pcmcia_socket_mutex);
-
/*
* Ugly. But we want to wait for the socket threads to have started up.
* We really should let the drivers themselves drive some of this..
@@ -1397,10 +1365,7 @@ static void pcmcia_bus_remove_socket(str
pcmcia_deregister_client(socket->pcmcia->handle);
- down(&pcmcia_socket_mutex);
pcmcia_bus_remove_card(socket->pcmcia);
- list_del(&socket->pcmcia->socket_list);
- up(&pcmcia_socket_mutex);
socket->pcmcia->state |= DS_SOCKET_DEAD;
pcmcia_put_bus_socket(socket->pcmcia);
_