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Commit aa584ca4 authored by Dominik Brodowski's avatar Dominik Brodowski
Browse files

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: default avatarWolfram Sang <w.sang@pengutronix.de>
Signed-off-by: default avatarDominik Brodowski <linux@dominikbrodowski.net>
parent af461fc1

drivers/pcmcia/ds.c

+22 −70
Original line number Diff line number Diff line
@@ -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;

include/pcmcia/ss.h

+3 −8
Original line number Diff line number Diff line
@@ -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;