diff options
Diffstat (limited to 'extras/recipes-kernel/linux/linux-omap/linus/0013-ueagle-atm-fix-PHY-signal-initialization-race.patch')
| -rw-r--r-- | extras/recipes-kernel/linux/linux-omap/linus/0013-ueagle-atm-fix-PHY-signal-initialization-race.patch | 100 |
1 files changed, 100 insertions, 0 deletions
diff --git a/extras/recipes-kernel/linux/linux-omap/linus/0013-ueagle-atm-fix-PHY-signal-initialization-race.patch b/extras/recipes-kernel/linux/linux-omap/linus/0013-ueagle-atm-fix-PHY-signal-initialization-race.patch new file mode 100644 index 00000000..e62a9d8c --- /dev/null +++ b/extras/recipes-kernel/linux/linux-omap/linus/0013-ueagle-atm-fix-PHY-signal-initialization-race.patch @@ -0,0 +1,100 @@ +From c23a13703fb00384d49a00875fc12a5e00f1946a Mon Sep 17 00:00:00 2001 +From: Dan Williams <dcbw@redhat.com> +Date: Sun, 19 Dec 2010 08:17:50 +0000 +Subject: [PATCH 13/65] ueagle-atm: fix PHY signal initialization race + +A race exists when initializing ueagle-atm devices where the generic atm +device may not yet be created before the driver attempts to initialize +it's PHY signal state, which checks whether the atm device has been +created or not. This often causes the sysfs 'carrier' attribute to be +'1' even though no signal has actually been found. + +uea_probe + usbatm_usb_probe + driver->bind (uea_bind) + uea_boot + kthread_run(uea_kthread) uea_kthread + usbatm_atm_init uea_start_reset + atm_dev_register UPDATE_ATM_SIGNAL + +UPDATE_ATM_SIGNAL checks whether the ATM device has been created and if +not, will not update the PHY signal state. Because of the race that +does not always happen in time, and the PHY signal state remains +ATM_PHY_SIG_FOUND even though no signal exists. + +To fix the race, just create the kthread during initialization, and only +after initialization is complete, start the thread that reboots the +device and initializes PHY state. + +[ 3030.490931] uea_probe: calling usbatm_usb_probe +[ 3030.490946] ueagle-atm 8-2:1.0: usbatm_usb_probe: trying driver ueagle-atm with vendor=1110, product=9031, ifnum 0 +[ 3030.493691] uea_bind: setting usbatm +[ 3030.496932] usb 8-2: [ueagle-atm] using iso mode +[ 3030.497283] ueagle-atm 8-2:1.0: usbatm_usb_probe: using 3021 byte buffer for rx channel 0xffff880125953508 + <kthread already started before usbatm_usb_probe() has returned> +[ 3030.497292] usb 8-2: [ueagle-atm] (re)booting started + <UPDATE_ATM_SIGNAL checks whether ATM device has been created yet before setting PHY state> +[ 3030.497298] uea_start_reset: atm dev (null) + <and since it hasn't been created yet PHY state is not set> +[ 3030.497306] ueagle-atm 8-2:1.0: usbatm_usb_probe: using 3392 byte buffer for tx channel 0xffff8801259535b8 +[ 3030.497374] usbatm_usb_probe: about to init +[ 3030.497379] usbatm_usb_probe: calling usbatm_atm_init + <atm device finally gets created> +[ 3030.497384] usbatm_atm_init: creating atm device! + +Signed-off-by: Dan Williams <dcbw@redhat.com> +Signed-off-by: David S. Miller <davem@davemloft.net> +--- + drivers/usb/atm/ueagle-atm.c | 22 +++++++++++++++++++--- + 1 files changed, 19 insertions(+), 3 deletions(-) + +diff --git a/drivers/usb/atm/ueagle-atm.c b/drivers/usb/atm/ueagle-atm.c +index 44447f5..99ac70e 100644 +--- a/drivers/usb/atm/ueagle-atm.c ++++ b/drivers/usb/atm/ueagle-atm.c +@@ -2206,8 +2206,11 @@ static int uea_boot(struct uea_softc *sc) + goto err1; + } + +- sc->kthread = kthread_run(uea_kthread, sc, "ueagle-atm"); +- if (sc->kthread == ERR_PTR(-ENOMEM)) { ++ /* Create worker thread, but don't start it here. Start it after ++ * all usbatm generic initialization is done. ++ */ ++ sc->kthread = kthread_create(uea_kthread, sc, "ueagle-atm"); ++ if (IS_ERR(sc->kthread)) { + uea_err(INS_TO_USBDEV(sc), "failed to create thread\n"); + goto err2; + } +@@ -2624,6 +2627,7 @@ static struct usbatm_driver uea_usbatm_driver = { + static int uea_probe(struct usb_interface *intf, const struct usb_device_id *id) + { + struct usb_device *usb = interface_to_usbdev(intf); ++ int ret; + + uea_enters(usb); + uea_info(usb, "ADSL device founded vid (%#X) pid (%#X) Rev (%#X): %s\n", +@@ -2637,7 +2641,19 @@ static int uea_probe(struct usb_interface *intf, const struct usb_device_id *id) + if (UEA_IS_PREFIRM(id)) + return uea_load_firmware(usb, UEA_CHIP_VERSION(id)); + +- return usbatm_usb_probe(intf, id, &uea_usbatm_driver); ++ ret = usbatm_usb_probe(intf, id, &uea_usbatm_driver); ++ if (ret == 0) { ++ struct usbatm_data *usbatm = usb_get_intfdata(intf); ++ struct uea_softc *sc = usbatm->driver_data; ++ ++ /* Ensure carrier is initialized to off as early as possible */ ++ UPDATE_ATM_SIGNAL(ATM_PHY_SIG_LOST); ++ ++ /* Only start the worker thread when all init is done */ ++ wake_up_process(sc->kthread); ++ } ++ ++ return ret; + } + + static void uea_disconnect(struct usb_interface *intf) +-- +1.6.6.1 + |