[PATCH 15/22] pcmcia: use state machine for extended requery
Dominik Brodowski
linux at dominikbrodowski.net
Sun Jan 24 12:32:45 EST 2010
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.
Signed-off-by: Dominik Brodowski <linux at dominikbrodowski.net>
---
drivers/pcmcia/ds.c | 92 ++++++++++++--------------------------------------
include/pcmcia/ss.h | 11 ++----
2 files changed, 25 insertions(+), 78 deletions(-)
diff --git a/drivers/pcmcia/ds.c b/drivers/pcmcia/ds.c
index 3105650..1b16a0f 100644
--- 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
--- 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;
--
1.6.3.3
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