On 10/08/11 10:33, Manohar Vanga wrote: > This patch adds a list which keeps track of all registered VME > buses. This is required for adding refcounting later to bridge > modules, something that is not currently implemented. > > This is based on the changes introduced by Emilio G. Cota in the > patch: > > https://lkml.org/lkml/2010/10/25/486 > > Signed-off-by: Manohar Vanga <manohar.vanga@xxxxxxx> Looks OK: Acked-by: Martyn Welch <martyn.welch@xxxxxx> > --- > drivers/staging/vme/vme.c | 46 ++++++++++++++++++++----------------- > drivers/staging/vme/vme_bridge.h | 1 + > 2 files changed, 26 insertions(+), 21 deletions(-) > > diff --git a/drivers/staging/vme/vme.c b/drivers/staging/vme/vme.c > index 15a6161..f811d07 100644 > --- a/drivers/staging/vme/vme.c > +++ b/drivers/staging/vme/vme.c > @@ -34,9 +34,10 @@ > #include "vme.h" > #include "vme_bridge.h" > > -/* Bitmask and mutex to keep track of bridge numbers */ > +/* Bitmask and list of registered buses both protected by common mutex */ > static unsigned int vme_bus_numbers; > -static DEFINE_MUTEX(vme_bus_num_mtx); > +static LIST_HEAD(vme_bus_list); > +static DEFINE_MUTEX(vme_buses_lock); > > static void __exit vme_exit(void); > static int __init vme_init(void); > @@ -1309,11 +1310,12 @@ EXPORT_SYMBOL(vme_slot_get); > > /* - Bridge Registration --------------------------------------------------- */ > > -/* call with vme_bus_num_mtx held */ > -static int __vme_alloc_bus_num(int bus_num) > +/* call with vme_buses_lock held */ > +static int __vme_add_bus(struct vme_bridge *bridge) > { > int num; > int i; > + int bus_num = bridge->num; > > if (bus_num == -1) { > /* try to find a free bus number */ > @@ -1335,25 +1337,29 @@ static int __vme_alloc_bus_num(int bus_num) > } > num = bus_num; > } > + bridge->num = num; > + list_add_tail(&bridge->bus_list, &vme_bus_list); > vme_bus_numbers |= 1 << num; > - return num; > + return 0; > } > > -static int vme_alloc_bus_num(int bus_num) > +static int vme_add_bus(struct vme_bridge *bridge) > { > - int num; > + int ret; > > - mutex_lock(&vme_bus_num_mtx); > - num = __vme_alloc_bus_num(bus_num); > - mutex_unlock(&vme_bus_num_mtx); > - return num; > + mutex_lock(&vme_buses_lock); > + ret = __vme_add_bus(bridge); > + mutex_unlock(&vme_buses_lock); > + > + return ret; > } > > -static void vme_free_bus_num(int bus) > +static void vme_remove_bus(struct vme_bridge *bridge) > { > - mutex_lock(&vme_bus_num_mtx); > - vme_bus_numbers &= ~(0x1 << bus); > - mutex_unlock(&vme_bus_num_mtx); > + mutex_lock(&vme_buses_lock); > + vme_bus_numbers &= ~(1 << bridge->num); > + list_del(&bridge->bus_list); > + mutex_unlock(&vme_buses_lock); > } > > int vme_register_bridge(struct vme_bridge *bridge) > @@ -1362,12 +1368,10 @@ int vme_register_bridge(struct vme_bridge *bridge) > int retval; > int i; > > - retval = vme_alloc_bus_num(bridge->num); > - if (retval < 0) > + retval = vme_add_bus(bridge); > + if (retval) > return retval; > > - bridge->num = retval; > - > /* This creates 32 vme "slot" devices. This equates to a slot for each > * ID available in a system conforming to the ANSI/VITA 1-1994 > * specification. > @@ -1398,7 +1402,7 @@ err_reg: > dev = &bridge->dev[i]; > device_unregister(dev); > } > - vme_free_bus_num(bridge->num); > + vme_remove_bus(bridge); > return retval; > } > EXPORT_SYMBOL(vme_register_bridge); > @@ -1413,7 +1417,7 @@ void vme_unregister_bridge(struct vme_bridge *bridge) > dev = &bridge->dev[i]; > device_unregister(dev); > } > - vme_free_bus_num(bridge->num); > + vme_remove_bus(bridge); > } > EXPORT_SYMBOL(vme_unregister_bridge); > > diff --git a/drivers/staging/vme/vme_bridge.h b/drivers/staging/vme/vme_bridge.h > index a9084f0..8959670 100644 > --- a/drivers/staging/vme/vme_bridge.h > +++ b/drivers/staging/vme/vme_bridge.h > @@ -112,6 +112,7 @@ struct vme_bridge { > /* Bridge Info - XXX Move to private structure? */ > struct device *parent; /* Parent device (eg. pdev->dev for PCI) */ > void *driver_priv; /* Private pointer for the bridge driver */ > + struct list_head bus_list; /* list of VME buses */ > > struct device dev[VME_SLOTS_MAX]; /* Device registered with > * device model on VME bus -- Martyn Welch (Principal Software Engineer) | Registered in England and GE Intelligent Platforms | Wales (3828642) at 100 T +44(0)127322748 | Barbirolli Square, Manchester, E martyn.welch@xxxxxx | M2 3AB VAT:GB 927559189 _______________________________________________ devel mailing list devel@xxxxxxxxxxxxxxxxxxxxxx http://driverdev.linuxdriverproject.org/mailman/listinfo/devel
