uwb: don't unbind the radio controller driver when resetting
Use pre_reset and post_reset methods to avoid unbinding the radio
controller driver after a uwb_rc_reset_all() call. This avoids a
deadlock in uwb_rc_rm() when waiting for the uwb event thread to stop.
Signed-off-by: David Vrabel <david.vrabel@csr.com>
diff --git a/drivers/uwb/hwa-rc.c b/drivers/uwb/hwa-rc.c
index 18009c9..158e98d 100644
--- a/drivers/uwb/hwa-rc.c
+++ b/drivers/uwb/hwa-rc.c
@@ -881,6 +881,24 @@
uwb_rc_put(uwb_rc); /* when creating the device, refcount = 1 */
}
+static int hwarc_pre_reset(struct usb_interface *iface)
+{
+ struct hwarc *hwarc = usb_get_intfdata(iface);
+ struct uwb_rc *uwb_rc = hwarc->uwb_rc;
+
+ uwb_rc_pre_reset(uwb_rc);
+ return 0;
+}
+
+static int hwarc_post_reset(struct usb_interface *iface)
+{
+ struct hwarc *hwarc = usb_get_intfdata(iface);
+ struct uwb_rc *uwb_rc = hwarc->uwb_rc;
+
+ uwb_rc_post_reset(uwb_rc);
+ return 0;
+}
+
/** USB device ID's that we handle */
static struct usb_device_id hwarc_id_table[] = {
/* D-Link DUB-1210 */
@@ -897,9 +915,11 @@
static struct usb_driver hwarc_driver = {
.name = "hwa-rc",
+ .id_table = hwarc_id_table,
.probe = hwarc_probe,
.disconnect = hwarc_disconnect,
- .id_table = hwarc_id_table,
+ .pre_reset = hwarc_pre_reset,
+ .post_reset = hwarc_post_reset,
};
static int __init hwarc_driver_init(void)
diff --git a/drivers/uwb/reset.c b/drivers/uwb/reset.c
index 8de856f..e39b3209 100644
--- a/drivers/uwb/reset.c
+++ b/drivers/uwb/reset.c
@@ -323,17 +323,16 @@
struct uwb_rc *rc = evt->rc;
int ret;
- /* Need to prevent the RC hardware module going away while in
- the rc->reset() call. */
- if (!try_module_get(rc->owner))
- return 0;
-
dev_info(&rc->uwb_dev.dev, "resetting radio controller\n");
ret = rc->reset(rc);
- if (ret)
+ if (ret) {
dev_err(&rc->uwb_dev.dev, "failed to reset hardware: %d\n", ret);
-
- module_put(rc->owner);
+ goto error;
+ }
+ return 0;
+error:
+ /* Nothing can be done except try the reset again. */
+ uwb_rc_reset_all(rc);
return ret;
}
@@ -360,3 +359,37 @@
uwbd_event_queue(evt);
}
EXPORT_SYMBOL_GPL(uwb_rc_reset_all);
+
+void uwb_rc_pre_reset(struct uwb_rc *rc)
+{
+ rc->stop(rc);
+ uwbd_flush(rc);
+
+ mutex_lock(&rc->uwb_dev.mutex);
+ rc->beaconing = -1;
+ rc->scanning = -1;
+ mutex_unlock(&rc->uwb_dev.mutex);
+
+ uwb_rsv_remove_all(rc);
+}
+EXPORT_SYMBOL_GPL(uwb_rc_pre_reset);
+
+void uwb_rc_post_reset(struct uwb_rc *rc)
+{
+ int ret;
+
+ ret = rc->start(rc);
+ if (ret)
+ goto error;
+ ret = uwb_rc_mac_addr_set(rc, &rc->uwb_dev.mac_addr);
+ if (ret)
+ goto error;
+ ret = uwb_rc_dev_addr_set(rc, &rc->uwb_dev.dev_addr);
+ if (ret)
+ goto error;
+ return;
+error:
+ /* Nothing can be done except try the reset again. */
+ uwb_rc_reset_all(rc);
+}
+EXPORT_SYMBOL_GPL(uwb_rc_post_reset);
diff --git a/drivers/uwb/rsv.c b/drivers/uwb/rsv.c
index ce00946..3d76efe 100644
--- a/drivers/uwb/rsv.c
+++ b/drivers/uwb/rsv.c
@@ -659,6 +659,25 @@
uwb_rsv_sched_update(rsv->rc);
}
+/**
+ * uwb_rsv_remove_all - remove all reservations
+ * @rc: the radio controller
+ *
+ * A DRP IE update is not done.
+ */
+void uwb_rsv_remove_all(struct uwb_rc *rc)
+{
+ struct uwb_rsv *rsv, *t;
+
+ mutex_lock(&rc->rsvs_mutex);
+ list_for_each_entry_safe(rsv, t, &rc->reservations, rc_node) {
+ uwb_rsv_remove(rsv);
+ }
+ mutex_unlock(&rc->rsvs_mutex);
+
+ cancel_work_sync(&rc->rsv_update_work);
+}
+
void uwb_rsv_init(struct uwb_rc *rc)
{
INIT_LIST_HEAD(&rc->reservations);
@@ -682,14 +701,6 @@
void uwb_rsv_cleanup(struct uwb_rc *rc)
{
- struct uwb_rsv *rsv, *t;
-
- mutex_lock(&rc->rsvs_mutex);
- list_for_each_entry_safe(rsv, t, &rc->reservations, rc_node) {
- uwb_rsv_remove(rsv);
- }
- mutex_unlock(&rc->rsvs_mutex);
-
- cancel_work_sync(&rc->rsv_update_work);
+ uwb_rsv_remove_all(rc);
destroy_workqueue(rc->rsv_workq);
}
diff --git a/drivers/uwb/umc-bus.c b/drivers/uwb/umc-bus.c
index 2d8d62d..5ad3616 100644
--- a/drivers/uwb/umc-bus.c
+++ b/drivers/uwb/umc-bus.c
@@ -11,23 +11,48 @@
#include <linux/uwb/umc.h>
#include <linux/pci.h>
-static int umc_bus_unbind_helper(struct device *dev, void *data)
+static int umc_bus_pre_reset_helper(struct device *dev, void *data)
{
- struct device *parent = data;
+ int ret = 0;
- if (dev->parent == parent && dev->driver)
- device_release_driver(dev);
- return 0;
+ if (dev->driver) {
+ struct umc_dev *umc = to_umc_dev(dev);
+ struct umc_driver *umc_drv = to_umc_driver(dev->driver);
+
+ if (umc_drv->pre_reset)
+ ret = umc_drv->pre_reset(umc);
+ else
+ device_release_driver(dev);
+ }
+ return ret;
+}
+
+static int umc_bus_post_reset_helper(struct device *dev, void *data)
+{
+ int ret = 0;
+
+ if (dev->driver) {
+ struct umc_dev *umc = to_umc_dev(dev);
+ struct umc_driver *umc_drv = to_umc_driver(dev->driver);
+
+ if (umc_drv->post_reset)
+ ret = umc_drv->post_reset(umc);
+ } else
+ ret = device_attach(dev);
+
+ return ret;
}
/**
* umc_controller_reset - reset the whole UMC controller
* @umc: the UMC device for the radio controller.
*
- * Drivers will be unbound from all UMC devices belonging to the
- * controller and then the radio controller will be rebound. The
- * radio controller is expected to do a full hardware reset when it is
- * probed.
+ * Drivers or all capabilities of the controller will have their
+ * pre_reset methods called or be unbound from their device. Then all
+ * post_reset methods will be called or the drivers will be rebound.
+ *
+ * Radio controllers must provide pre_reset and post_reset methods and
+ * reset the hardware in their start method.
*
* If this is called while a probe() or remove() is in progress it
* will return -EAGAIN and not perform the reset.
@@ -35,14 +60,13 @@
int umc_controller_reset(struct umc_dev *umc)
{
struct device *parent = umc->dev.parent;
- int ret;
+ int ret = 0;
- if (down_trylock(&parent->sem))
+ if(down_trylock(&parent->sem))
return -EAGAIN;
- bus_for_each_dev(&umc_bus_type, NULL, parent, umc_bus_unbind_helper);
- ret = device_attach(&umc->dev);
- if (ret == 1)
- ret = 0;
+ ret = device_for_each_child(parent, parent, umc_bus_pre_reset_helper);
+ if (ret >= 0)
+ device_for_each_child(parent, parent, umc_bus_post_reset_helper);
up(&parent->sem);
return ret;
@@ -75,10 +99,10 @@
if (!dev->driver)
ret = device_attach(dev);
- return ret < 0 ? ret : 0;
+ return ret;
}
-static void umc_bus_rescan(void)
+static void umc_bus_rescan(struct device *parent)
{
int err;
@@ -86,7 +110,7 @@
* We can't use bus_rescan_devices() here as it deadlocks when
* it tries to retake the dev->parent semaphore.
*/
- err = bus_for_each_dev(&umc_bus_type, NULL, NULL, umc_bus_rescan_helper);
+ err = device_for_each_child(parent, NULL, umc_bus_rescan_helper);
if (err < 0)
printk(KERN_WARNING "%s: rescan of bus failed: %d\n",
KBUILD_MODNAME, err);
@@ -120,7 +144,7 @@
if (err)
put_device(dev);
else
- umc_bus_rescan();
+ umc_bus_rescan(dev->parent);
return err;
}
diff --git a/drivers/uwb/uwb-internal.h b/drivers/uwb/uwb-internal.h
index 4c24496..af95541 100644
--- a/drivers/uwb/uwb-internal.h
+++ b/drivers/uwb/uwb-internal.h
@@ -248,6 +248,7 @@
void uwb_rsv_init(struct uwb_rc *rc);
int uwb_rsv_setup(struct uwb_rc *rc);
void uwb_rsv_cleanup(struct uwb_rc *rc);
+void uwb_rsv_remove_all(struct uwb_rc *rc);
void uwb_rsv_set_state(struct uwb_rsv *rsv, enum uwb_rsv_state new_state);
void uwb_rsv_remove(struct uwb_rsv *rsv);
diff --git a/drivers/uwb/whc-rc.c b/drivers/uwb/whc-rc.c
index 6c454ea..e0d6693 100644
--- a/drivers/uwb/whc-rc.c
+++ b/drivers/uwb/whc-rc.c
@@ -394,7 +394,7 @@
le_writel(0, whcrc->rc_base + URCCMD);
whci_wait_for(&umc_dev->dev, whcrc->rc_base + URCSTS,
- URCSTS_HALTED, 0, 40, "URCSTS.HALTED");
+ URCSTS_HALTED, URCSTS_HALTED, 100, "URCSTS.HALTED");
}
static void whcrc_init(struct whcrc *whcrc)
@@ -488,6 +488,24 @@
d_printf(1, &umc_dev->dev, "freed whcrc %p\n", whcrc);
}
+static int whcrc_pre_reset(struct umc_dev *umc)
+{
+ struct whcrc *whcrc = umc_get_drvdata(umc);
+ struct uwb_rc *uwb_rc = whcrc->uwb_rc;
+
+ uwb_rc_pre_reset(uwb_rc);
+ return 0;
+}
+
+static int whcrc_post_reset(struct umc_dev *umc)
+{
+ struct whcrc *whcrc = umc_get_drvdata(umc);
+ struct uwb_rc *uwb_rc = whcrc->uwb_rc;
+
+ uwb_rc_post_reset(uwb_rc);
+ return 0;
+}
+
/* PCI device ID's that we handle [so it gets loaded] */
static struct pci_device_id whcrc_id_table[] = {
{ PCI_DEVICE_CLASS(PCI_CLASS_WIRELESS_WHCI, ~0) },
@@ -496,10 +514,12 @@
MODULE_DEVICE_TABLE(pci, whcrc_id_table);
static struct umc_driver whcrc_driver = {
- .name = "whc-rc",
- .cap_id = UMC_CAP_ID_WHCI_RC,
- .probe = whcrc_probe,
- .remove = whcrc_remove,
+ .name = "whc-rc",
+ .cap_id = UMC_CAP_ID_WHCI_RC,
+ .probe = whcrc_probe,
+ .remove = whcrc_remove,
+ .pre_reset = whcrc_pre_reset,
+ .post_reset = whcrc_post_reset,
};
static int __init whcrc_driver_init(void)