From ca88fc2ef0d790a1da37804219102336f7622b97 Mon Sep 17 00:00:00 2001 From: Daniel Mack Date: Wed, 2 Apr 2014 13:58:28 +0200 Subject: [PATCH] usb: musb: add a work_struct to recover from babble errors Handle BABBLE interrupt error conditions from a work struct handler. This indirection is necessary as we can't be certain that the phy functions don't sleep. Platform layer implementation may pass a babble error down to the core in order to handle it. Signed-off-by: Daniel Mack Signed-off-by: Felipe Balbi --- drivers/usb/musb/musb_core.c | 35 +++++++++++++++++++++++++++++++++++ drivers/usb/musb/musb_core.h | 1 + 2 files changed, 36 insertions(+) diff --git a/drivers/usb/musb/musb_core.c b/drivers/usb/musb/musb_core.c index 07576907e2c6..61da471b7aed 100644 --- a/drivers/usb/musb/musb_core.c +++ b/drivers/usb/musb/musb_core.c @@ -848,6 +848,10 @@ b_host: } } + /* handle babble condition */ + if (int_usb & MUSB_INTR_BABBLE) + schedule_work(&musb->recover_work); + #if 0 /* REVISIT ... this would be for multiplexing periodic endpoints, or * supporting transfer phasing to prevent exceeding ISO bandwidth @@ -1746,6 +1750,34 @@ static void musb_irq_work(struct work_struct *data) } } +/* Recover from babble interrupt conditions */ +static void musb_recover_work(struct work_struct *data) +{ + struct musb *musb = container_of(data, struct musb, recover_work); + int status; + + musb_platform_reset(musb); + + usb_phy_vbus_off(musb->xceiv); + udelay(100); + + usb_phy_vbus_on(musb->xceiv); + udelay(100); + + /* + * When a babble condition occurs, the musb controller removes the + * session bit and the endpoint config is lost. + */ + if (musb->dyn_fifo) + status = ep_config_from_table(musb); + else + status = ep_config_from_hw(musb); + + /* start the session again */ + if (status == 0) + musb_start(musb); +} + /* -------------------------------------------------------------------------- * Init support */ @@ -1913,6 +1945,7 @@ musb_init_controller(struct device *dev, int nIrq, void __iomem *ctrl) /* Init IRQ workqueue before request_irq */ INIT_WORK(&musb->irq_work, musb_irq_work); + INIT_WORK(&musb->recover_work, musb_recover_work); INIT_DELAYED_WORK(&musb->deassert_reset_work, musb_deassert_reset); INIT_DELAYED_WORK(&musb->finish_resume_work, musb_host_finish_resume); @@ -2008,6 +2041,7 @@ fail4: fail3: cancel_work_sync(&musb->irq_work); + cancel_work_sync(&musb->recover_work); cancel_delayed_work_sync(&musb->finish_resume_work); cancel_delayed_work_sync(&musb->deassert_reset_work); if (musb->dma_controller) @@ -2073,6 +2107,7 @@ static int musb_remove(struct platform_device *pdev) dma_controller_destroy(musb->dma_controller); cancel_work_sync(&musb->irq_work); + cancel_work_sync(&musb->recover_work); cancel_delayed_work_sync(&musb->finish_resume_work); cancel_delayed_work_sync(&musb->deassert_reset_work); musb_free(musb); diff --git a/drivers/usb/musb/musb_core.h b/drivers/usb/musb/musb_core.h index 5514e4c82932..47e88747e3a7 100644 --- a/drivers/usb/musb/musb_core.h +++ b/drivers/usb/musb/musb_core.h @@ -297,6 +297,7 @@ struct musb { irqreturn_t (*isr)(int, void *); struct work_struct irq_work; + struct work_struct recover_work; struct delayed_work deassert_reset_work; struct delayed_work finish_resume_work; u16 hwvers; -- 2.30.2