pcmcia: use state machine for extended requery

The requery callback now also handles the addition of a second pseudo
multifunction device. Avoids messing with dev_{g,s}et_drvdata(), and
fixes any workqueue <-> skt_mutex deadlock.

Tested-by: Wolfram Sang <w.sang@pengutronix.de>
Signed-off-by: Dominik Brodowski <linux@dominikbrodowski.net>

diff --git a/drivers/pcmcia/ds.c b/drivers/pcmcia/ds.c
index 5400e20..9968c0d 100644 (file)
--- a/drivers/pcmcia/ds.c
+++ b/drivers/pcmcia/ds.c
@@ -244,23 +244,11 @@ static void pcmcia_release_dev(struct device *dev)
        kfree(p_dev);
 }
 
-static void pcmcia_add_device_later(struct pcmcia_socket *s, int mfc)
-{
-       if (!s->pcmcia_state.device_add_pending) {
-               dev_dbg(&s->dev, "scheduling to add %s secondary"
-                      " device to %d\n", mfc ? "mfc" : "pfc", s->sock);
-               s->pcmcia_state.device_add_pending = 1;
-               s->pcmcia_state.mfc_pfc = mfc;
-               schedule_work(&s->device_add);
-       }
-       return;
-}
 
 static int pcmcia_device_probe(struct device *dev)
 {
        struct pcmcia_device *p_dev;
        struct pcmcia_driver *p_drv;
-       struct pcmcia_device_id *did;
        struct pcmcia_socket *s;
        cistpl_config_t cis_config;
        int ret = 0;
@@ -273,18 +261,6 @@ static int pcmcia_device_probe(struct device *dev)
        p_drv = to_pcmcia_drv(dev->driver);
        s = p_dev->socket;
 
-       /* The PCMCIA code passes the match data in via dev_set_drvdata(dev)
-        * which is an ugly hack. Once the driver probe is called it may
-        * and often will overwrite the match data so we must save it first
-        *
-        * handle pseudo multifunction devices:
-        * there are at most two pseudo multifunction devices.
-        * if we're matching against the first, schedule a
-        * call which will then check whether there are two
-        * pseudo devices, and if not, add the second one.
-        */
-       did = dev_get_drvdata(&p_dev->dev);
-
        dev_dbg(dev, "trying to bind to %s\n", p_drv->drv.name);
 
        if ((!p_drv->probe) || (!p_dev->function_config) ||
@@ -314,9 +290,9 @@ static int pcmcia_device_probe(struct device *dev)
        }
 
        mutex_lock(&s->ops_mutex);
-       if (did && (did->match_flags & PCMCIA_DEV_ID_MATCH_DEVICE_NO) &&
+       if ((s->pcmcia_state.has_pfc) &&
            (p_dev->socket->device_count == 1) && (p_dev->device_no == 0))
-               pcmcia_add_device_later(p_dev->socket, 0);
+               pcmcia_parse_uevents(s, PCMCIA_UEVENT_REQUERY);
        mutex_unlock(&s->ops_mutex);
 
 put_module:
@@ -369,7 +345,6 @@ static int pcmcia_device_remove(struct device *dev)
 {
        struct pcmcia_device *p_dev;
        struct pcmcia_driver *p_drv;
-       struct pcmcia_device_id *did;
        int i;
 
        p_dev = to_pcmcia_dev(dev);
@@ -381,8 +356,7 @@ static int pcmcia_device_remove(struct device *dev)
         * pseudo multi-function card, we need to unbind
         * all devices
         */
-       did = dev_get_drvdata(&p_dev->dev);
-       if (did && (did->match_flags & PCMCIA_DEV_ID_MATCH_DEVICE_NO) &&
+       if ((p_dev->socket->pcmcia_state.has_pfc) &&
            (p_dev->socket->device_count > 0) &&
            (p_dev->device_no == 0))
                pcmcia_card_remove(p_dev->socket, p_dev);
@@ -528,8 +502,8 @@ struct pcmcia_device *pcmcia_device_add(struct pcmcia_socket *s, unsigned int fu
        p_dev->device_no = (s->device_count++);
        mutex_unlock(&s->ops_mutex);
 
-       /* max of 4 devices per card */
-       if (p_dev->device_no >= 4)
+       /* max of 2 devices per card */
+       if (p_dev->device_no >= 2)
                goto err_free;
 
        p_dev->socket = s;
@@ -652,22 +626,6 @@ static int pcmcia_card_add(struct pcmcia_socket *s)
 }
 
 
-static void pcmcia_delayed_add_device(struct work_struct *work)
-{
-       struct pcmcia_socket *s =
-               container_of(work, struct pcmcia_socket, device_add);
-       u8 mfc_pfc;
-
-       mutex_lock(&s->ops_mutex);
-       mfc_pfc = s->pcmcia_state.mfc_pfc;
-       s->pcmcia_state.device_add_pending = 0;
-       s->pcmcia_state.mfc_pfc = 0;
-       mutex_unlock(&s->ops_mutex);
-
-       dev_dbg(&s->dev, "adding additional device to %d\n", s->sock);
-       pcmcia_device_add(s, mfc_pfc);
-}
-
 static int pcmcia_requery_callback(struct device *dev, void * _data)
 {
        struct pcmcia_device *p_dev = to_pcmcia_dev(dev);
@@ -679,9 +637,10 @@ static int pcmcia_requery_callback(struct device *dev, void * _data)
        return 0;
 }
 
+
 static void pcmcia_requery(struct pcmcia_socket *s)
 {
-       int present;
+       int present, has_pfc;
 
        mutex_lock(&s->ops_mutex);
        present = s->pcmcia_state.present;
@@ -723,6 +682,15 @@ static void pcmcia_requery(struct pcmcia_socket *s)
                }
        }
 
+       /* If the PCMCIA device consists of two pseudo devices,
+        * call pcmcia_device_add() -- which will fail if both
+        * devices are already registered. */
+       mutex_lock(&s->ops_mutex);
+       has_pfc = s->pcmcia_state.has_pfc;
+       mutex_unlock(&s->ops_mutex);
+       if (has_pfc)
+               pcmcia_device_add(s, 0);
+
        /* we re-scan all devices, not just the ones connected to this
         * socket. This does not matter, though. */
        if (bus_rescan_devices(&pcmcia_bus_type))
@@ -746,9 +714,6 @@ static int pcmcia_load_firmware(struct pcmcia_device *dev, char * filename)
        struct pcmcia_socket *s = dev->socket;
        const struct firmware *fw;
        int ret = -ENOMEM;
-       int no_funcs;
-       int old_funcs;
-       cistpl_longlink_mfc_t mfc;
 
        if (!filename)
                return -EINVAL;
@@ -775,22 +740,8 @@ static int pcmcia_load_firmware(struct pcmcia_device *dev, char * filename)
                /* update information */
                pcmcia_device_query(dev);
 
-               /* does this cis override add or remove functions? */
-               old_funcs = s->functions;
-
-               if (!pccard_read_tuple(s, BIND_FN_ALL, CISTPL_LONGLINK_MFC, &mfc))
-                       no_funcs = mfc.nfn;
-               else
-                       no_funcs = 1;
-               s->functions = no_funcs;
-
-               if (old_funcs > no_funcs)
-                       pcmcia_card_remove(s, dev);
-               else if (no_funcs > old_funcs) {
-                       mutex_lock(&s->ops_mutex);
-                       pcmcia_add_device_later(s, 1);
-                       mutex_unlock(&s->ops_mutex);
-               }
+               /* requery (as number of functions might have changed) */
+               pcmcia_parse_uevents(s, PCMCIA_UEVENT_REQUERY);
        }
  release:
        release_firmware(fw);
@@ -857,6 +808,9 @@ static inline int pcmcia_devmatch(struct pcmcia_device *dev,
        if (did->match_flags & PCMCIA_DEV_ID_MATCH_DEVICE_NO) {
                if (dev->device_no != did->device_no)
                        return 0;
+               mutex_lock(&dev->socket->ops_mutex);
+               dev->socket->pcmcia_state.has_pfc = 1;
+               mutex_unlock(&dev->socket->ops_mutex);
        }
 
        if (did->match_flags & PCMCIA_DEV_ID_MATCH_FUNC_ID) {
@@ -905,8 +859,6 @@ static inline int pcmcia_devmatch(struct pcmcia_device *dev,
                        return 0;
        }
 
-       dev_set_drvdata(&dev->dev, did);
-
        return 1;
 }
 
@@ -1300,6 +1252,7 @@ static int ds_event(struct pcmcia_socket *skt, event_t event, int priority)
 
        case CS_EVENT_CARD_INSERTION:
                mutex_lock(&s->ops_mutex);
+               s->pcmcia_state.has_pfc = 0;
                s->pcmcia_state.present = 1;
                destroy_cis_cache(s); /* to be on the safe side... */
                mutex_unlock(&s->ops_mutex);
@@ -1411,7 +1364,6 @@ static int __devinit pcmcia_bus_add_socket(struct device *dev,
        init_waitqueue_head(&socket->queue);
 #endif
        INIT_LIST_HEAD(&socket->devices_list);
-       INIT_WORK(&socket->device_add, pcmcia_delayed_add_device);
        memset(&socket->pcmcia_state, 0, sizeof(u8));
        socket->device_count = 0;
 

diff --git a/include/pcmcia/ss.h b/include/pcmcia/ss.h
index ea5dec8..32896a7 100644 (file)
--- a/include/pcmcia/ss.h
+++ b/include/pcmcia/ss.h
@@ -230,18 +230,13 @@ struct pcmcia_socket {
                u8                      busy:1;
                /* pcmcia module is being unloaded */
                u8                      dead:1;
-               /* a multifunction-device add event is pending */
-               u8                      device_add_pending:1;
-               /* the pending event adds a mfc (1) or pfc (0) */
-               u8                      mfc_pfc:1;
+               /* the PCMCIA card consists of two pseudo devices */
+               u8                      has_pfc:1;
 
-               u8                      reserved:3;
+               u8                      reserved:4;
        } pcmcia_state;
 
 
-       /* for adding further pseudo-multifunction devices */
-       struct work_struct              device_add;
-
 #ifdef CONFIG_PCMCIA_IOCTL
        struct user_info_t              *user;
        wait_queue_head_t               queue;