From 307ba6dd73254fe7d2ce27db64ffd90e1bb3c6c0 Mon Sep 17 00:00:00 2001 From: David Vrabel Date: Fri, 7 Nov 2008 17:37:33 +0000 Subject: 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 --- drivers/uwb/hwa-rc.c | 22 +++++++++++++++- drivers/uwb/reset.c | 49 ++++++++++++++++++++++++++++++------ drivers/uwb/rsv.c | 29 +++++++++++++++------- drivers/uwb/umc-bus.c | 62 ++++++++++++++++++++++++++++++++-------------- drivers/uwb/uwb-internal.h | 1 + drivers/uwb/whc-rc.c | 30 ++++++++++++++++++---- include/linux/uwb.h | 2 ++ include/linux/uwb/umc.h | 2 ++ 8 files changed, 155 insertions(+), 42 deletions(-) diff --git a/drivers/uwb/hwa-rc.c b/drivers/uwb/hwa-rc.c index 18009c99577d..158e98d08af9 100644 --- a/drivers/uwb/hwa-rc.c +++ b/drivers/uwb/hwa-rc.c @@ -881,6 +881,24 @@ static void hwarc_disconnect(struct usb_interface *iface) 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 @@ MODULE_DEVICE_TABLE(usb, hwarc_id_table); 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 8de856fa7958..e39b32099af3 100644 --- a/drivers/uwb/reset.c +++ b/drivers/uwb/reset.c @@ -323,17 +323,16 @@ int uwbd_msg_handle_reset(struct uwb_event *evt) 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 @@ void uwb_rc_reset_all(struct uwb_rc *rc) 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 ce0094657d3d..3d76efe26acc 100644 --- a/drivers/uwb/rsv.c +++ b/drivers/uwb/rsv.c @@ -659,6 +659,25 @@ static void uwb_rsv_timer(unsigned long arg) 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 @@ int uwb_rsv_setup(struct uwb_rc *rc) 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 2d8d62d9f53e..5ad36164c13b 100644 --- a/drivers/uwb/umc-bus.c +++ b/drivers/uwb/umc-bus.c @@ -11,23 +11,48 @@ #include #include -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 @@ static int umc_bus_unbind_helper(struct device *dev, void *data) 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 @@ static int umc_bus_rescan_helper(struct device *dev, void *data) 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 @@ static void umc_bus_rescan(void) * 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 @@ static int umc_device_probe(struct device *dev) 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 4c2449679978..af95541dabcd 100644 --- a/drivers/uwb/uwb-internal.h +++ b/drivers/uwb/uwb-internal.h @@ -248,6 +248,7 @@ extern struct device_attribute dev_attr_scan; 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 6c454eadd307..e0d66938ccd8 100644 --- a/drivers/uwb/whc-rc.c +++ b/drivers/uwb/whc-rc.c @@ -394,7 +394,7 @@ void whcrc_stop_rc(struct uwb_rc *rc) 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 @@ static void whcrc_remove(struct umc_dev *umc_dev) 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 @@ static struct pci_device_id whcrc_id_table[] = { 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) diff --git a/include/linux/uwb.h b/include/linux/uwb.h index 881f0c5b6d28..c4854848999d 100644 --- a/include/linux/uwb.h +++ b/include/linux/uwb.h @@ -540,6 +540,8 @@ void uwb_rc_rm(struct uwb_rc *); void uwb_rc_neh_grok(struct uwb_rc *, void *, size_t); void uwb_rc_neh_error(struct uwb_rc *, int); void uwb_rc_reset_all(struct uwb_rc *rc); +void uwb_rc_pre_reset(struct uwb_rc *rc); +void uwb_rc_post_reset(struct uwb_rc *rc); /** * uwb_rsv_is_owner - is the owner of this reservation the RC? diff --git a/include/linux/uwb/umc.h b/include/linux/uwb/umc.h index 36a39e34f8d7..4b4fc0f43855 100644 --- a/include/linux/uwb/umc.h +++ b/include/linux/uwb/umc.h @@ -89,6 +89,8 @@ struct umc_driver { void (*remove)(struct umc_dev *); int (*suspend)(struct umc_dev *, pm_message_t state); int (*resume)(struct umc_dev *); + int (*pre_reset)(struct umc_dev *); + int (*post_reset)(struct umc_dev *); struct device_driver driver; }; -- cgit v1.2.3