From 681e9485241463e1e8d8cfd0a11fb252f49c997f Mon Sep 17 00:00:00 2001 From: Chunfeng Yun Date: Wed, 23 May 2018 16:53:20 +0800 Subject: usb: mtu3: fix warning of sleep in atomic context in notifier callback The notifier callbacks of extcon are called in atomic context, but the callbacks will call regulator_enable()/regulator_disable() which may sleep caused by mutex, so use work queue to call the sleep functions. Signed-off-by: Chunfeng Yun Signed-off-by: Greg Kroah-Hartman --- drivers/usb/mtu3/mtu3.h | 11 ++++++++++- drivers/usb/mtu3/mtu3_dr.c | 44 ++++++++++++++++++++++++++++++++++++-------- 2 files changed, 46 insertions(+), 9 deletions(-) (limited to 'drivers/usb') diff --git a/drivers/usb/mtu3/mtu3.h b/drivers/usb/mtu3/mtu3.h index a56fee05b04d..87823ac0d120 100644 --- a/drivers/usb/mtu3/mtu3.h +++ b/drivers/usb/mtu3/mtu3.h @@ -196,7 +196,12 @@ struct mtu3_gpd_ring { * @vbus: vbus 5V used by host mode * @edev: external connector used to detect vbus and iddig changes * @vbus_nb: notifier for vbus detection -* @vbus_nb: notifier for iddig(idpin) detection +* @vbus_work : work of vbus detection notifier, used to avoid sleep in +* notifier callback which is atomic context +* @vbus_event : event of vbus detecion notifier +* @id_nb : notifier for iddig(idpin) detection +* @id_work : work of iddig detection notifier +* @id_event : event of iddig detecion notifier * @is_u3_drd: whether port0 supports usb3.0 dual-role device or not * @manual_drd_enabled: it's true when supports dual-role device by debugfs * to switch host/device modes depending on user input. @@ -205,7 +210,11 @@ struct otg_switch_mtk { struct regulator *vbus; struct extcon_dev *edev; struct notifier_block vbus_nb; + struct work_struct vbus_work; + unsigned long vbus_event; struct notifier_block id_nb; + struct work_struct id_work; + unsigned long id_event; bool is_u3_drd; bool manual_drd_enabled; }; diff --git a/drivers/usb/mtu3/mtu3_dr.c b/drivers/usb/mtu3/mtu3_dr.c index 80083e092948..8c3bbf732bc4 100644 --- a/drivers/usb/mtu3/mtu3_dr.c +++ b/drivers/usb/mtu3/mtu3_dr.c @@ -174,16 +174,40 @@ static void ssusb_set_mailbox(struct otg_switch_mtk *otg_sx, } } -static int ssusb_id_notifier(struct notifier_block *nb, - unsigned long event, void *ptr) +static void ssusb_id_work(struct work_struct *work) { struct otg_switch_mtk *otg_sx = - container_of(nb, struct otg_switch_mtk, id_nb); + container_of(work, struct otg_switch_mtk, id_work); - if (event) + if (otg_sx->id_event) ssusb_set_mailbox(otg_sx, MTU3_ID_GROUND); else ssusb_set_mailbox(otg_sx, MTU3_ID_FLOAT); +} + +static void ssusb_vbus_work(struct work_struct *work) +{ + struct otg_switch_mtk *otg_sx = + container_of(work, struct otg_switch_mtk, vbus_work); + + if (otg_sx->vbus_event) + ssusb_set_mailbox(otg_sx, MTU3_VBUS_VALID); + else + ssusb_set_mailbox(otg_sx, MTU3_VBUS_OFF); +} + +/* + * @ssusb_id_notifier is called in atomic context, but @ssusb_set_mailbox + * may sleep, so use work queue here + */ +static int ssusb_id_notifier(struct notifier_block *nb, + unsigned long event, void *ptr) +{ + struct otg_switch_mtk *otg_sx = + container_of(nb, struct otg_switch_mtk, id_nb); + + otg_sx->id_event = event; + schedule_work(&otg_sx->id_work); return NOTIFY_DONE; } @@ -194,10 +218,8 @@ static int ssusb_vbus_notifier(struct notifier_block *nb, struct otg_switch_mtk *otg_sx = container_of(nb, struct otg_switch_mtk, vbus_nb); - if (event) - ssusb_set_mailbox(otg_sx, MTU3_VBUS_VALID); - else - ssusb_set_mailbox(otg_sx, MTU3_VBUS_OFF); + otg_sx->vbus_event = event; + schedule_work(&otg_sx->vbus_work); return NOTIFY_DONE; } @@ -398,6 +420,9 @@ int ssusb_otg_switch_init(struct ssusb_mtk *ssusb) { struct otg_switch_mtk *otg_sx = &ssusb->otg_switch; + INIT_WORK(&otg_sx->id_work, ssusb_id_work); + INIT_WORK(&otg_sx->vbus_work, ssusb_vbus_work); + if (otg_sx->manual_drd_enabled) ssusb_debugfs_init(ssusb); else @@ -412,4 +437,7 @@ void ssusb_otg_switch_exit(struct ssusb_mtk *ssusb) if (otg_sx->manual_drd_enabled) ssusb_debugfs_exit(ssusb); + + cancel_work_sync(&otg_sx->id_work); + cancel_work_sync(&otg_sx->vbus_work); } -- cgit v1.2.3