From: Swaminathan S <swami.iyer@xxxxxx> musb: fix for crash in DM646x USB when (CPPI)DMA is enabled Race condition exists between the cppi_interrupt handler and davinci_interrupt handler w.r.t completing a TX IO. Since DM646x has seperate DMA and USB endpoint interrupts cppi_interrupt handler needs to hold the lock while operating on the endpoint. Update over previous patch to avoid taking the lock if already taken. Tested on DM644x, DM355 and DM646x platforms. Signed-off-by: Swaminathan S <swami.iyer@xxxxxx> Acked-by: Sergei Shtylyov <sshtylyov@xxxxxxxxxxxxx> Acked-by: Anand Gadiyar <gadiyar@xxxxxx> --- drivers/usb/musb/cppi_dma.c | 6 ++++++ 1 files changed, 6 insertions(+), 0 deletions(-) diff --git a/drivers/usb/musb/cppi_dma.c b/drivers/usb/musb/cppi_dma.c index c3577bb..cc83ffa 100644 --- a/drivers/usb/musb/cppi_dma.c +++ b/drivers/usb/musb/cppi_dma.c @@ -1154,8 +1154,11 @@ irqreturn_t cppi_interrupt(int irq, void *dev_id) struct musb_hw_ep *hw_ep = NULL; u32 rx, tx; int i, index; + unsigned long flags; cppi = container_of(musb->dma_controller, struct cppi, controller); + if (cppi->irq) + spin_lock_irqsave(&musb->lock, flags); tibase = musb->ctrl_base; @@ -1285,6 +1288,9 @@ irqreturn_t cppi_interrupt(int irq, void *dev_id) /* write to CPPI EOI register to re-enable interrupts */ musb_writel(tibase, DAVINCI_CPPI_EOI_REG, 0); + if (cppi->irq) + spin_unlock_irqrestore(&musb->lock, flags); + return IRQ_HANDLED; } -- To unsubscribe from this list: send the line "unsubscribe linux-usb" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
