From 5bf54506b036412e05e6ea0f000d627d775e7afc Mon Sep 17 00:00:00 2001 From: Moiz Sonasath Date: Mon, 27 Jun 2011 10:01:01 -0500 Subject: [PATCH] USB: OTG: Use work_queue in set_vbus for TWL6030 transciever With this commit: cccad6d4b103e53fb3d1fc1467f654ecb572d047 usb: otg: notifier: switch to atomic notifier Following dumps are observed on attach/detach for MUSB HOST mode and on a detach for MUSB Device mode. BUG: sleeping function called from invalid context at kernel/mutex.c:85 where, the source is: twl6030_usb_irq ->atomic_notifier_call_chain ->musb_otg_notifications ->twl6030_set_vbus ->twl_i2c_write_u8 ->mutex_lock This patch moves the i2c writes in set_vbus function to a work-queue thereby avoiding I2C writes in atomic context. Tested HOST and Device mode functionality on OMAP4460 Signed-off-by: Moiz Sonasath Signed-off-by: Greg Kroah-Hartman --- drivers/usb/otg/twl6030-usb.c | 30 ++++++++++++++++++++++++------ 1 file changed, 24 insertions(+), 6 deletions(-) diff --git a/drivers/usb/otg/twl6030-usb.c b/drivers/usb/otg/twl6030-usb.c index cfb5aa7..b4d2c09 100644 --- a/drivers/usb/otg/twl6030-usb.c +++ b/drivers/usb/otg/twl6030-usb.c @@ -95,11 +95,15 @@ struct twl6030_usb { struct regulator *usb3v3; + /* used to set vbus, in atomic path */ + struct work_struct set_vbus_work; + int irq1; int irq2; u8 linkstat; u8 asleep; bool irq_enabled; + bool vbus_enable; unsigned long features; }; @@ -370,20 +374,31 @@ static int twl6030_enable_irq(struct otg_transceiver *x) return 0; } -static int twl6030_set_vbus(struct otg_transceiver *x, bool enabled) +static void otg_set_vbus_work(struct work_struct *data) { - struct twl6030_usb *twl = xceiv_to_twl(x); + struct twl6030_usb *twl = container_of(data, struct twl6030_usb, + set_vbus_work); /* * Start driving VBUS. Set OPA_MODE bit in CHARGERUSB_CTRL1 * register. This enables boost mode. */ - if (enabled) + + if (twl->vbus_enable) twl6030_writeb(twl, TWL_MODULE_MAIN_CHARGE , 0x40, - CHARGERUSB_CTRL1); - else + CHARGERUSB_CTRL1); + else twl6030_writeb(twl, TWL_MODULE_MAIN_CHARGE , 0x00, - CHARGERUSB_CTRL1); + CHARGERUSB_CTRL1); +} + +static int twl6030_set_vbus(struct otg_transceiver *x, bool enabled) +{ + struct twl6030_usb *twl = xceiv_to_twl(x); + + twl->vbus_enable = enabled; + schedule_work(&twl->set_vbus_work); + return 0; } @@ -444,6 +459,8 @@ static int __devinit twl6030_usb_probe(struct platform_device *pdev) ATOMIC_INIT_NOTIFIER_HEAD(&twl->otg.notifier); + INIT_WORK(&twl->set_vbus_work, otg_set_vbus_work); + twl->irq_enabled = true; status = request_threaded_irq(twl->irq1, NULL, twl6030_usbotg_irq, IRQF_TRIGGER_FALLING | IRQF_TRIGGER_RISING, @@ -494,6 +511,7 @@ static int __exit twl6030_usb_remove(struct platform_device *pdev) regulator_put(twl->usb3v3); pdata->phy_exit(twl->dev); device_remove_file(twl->dev, &dev_attr_vbus); + cancel_work_sync(&twl->set_vbus_work); kfree(twl); return 0; -- 2.7.4