From c03da38d5d4b28f6ab559c4df8646dbda536b674 Mon Sep 17 00:00:00 2001 From: Daniel Mack Date: Mon, 26 May 2014 14:52:36 +0200 Subject: [PATCH] usb: musb: use is_host_active() to distinguish between host and gadget mode On AM33xx platforms, unplugging a device in the middle of an active transfer leads to a drop of MUSB_DEVCTL_HM in MUSB_DEVCTL before the system is informed about a disconnect. This consequently makes the musb core call the gadget code to handle the interrupt request, which then crashes the kernel because the relevant pointers haven't been set up for gadget mode. To fix this, use is_host_active() rather than (devctl & MUSB_DEVCTL_HM) in musb_interrupt() and musb_dma_completion() to detect whether the controller is in host or peripheral mode. This information is provided by the driver logic and does not rely on register contents. Signed-off-by: Daniel Mack Signed-off-by: Felipe Balbi --- drivers/usb/musb/musb_core.c | 16 +++++++--------- 1 file changed, 7 insertions(+), 9 deletions(-) diff --git a/drivers/usb/musb/musb_core.c b/drivers/usb/musb/musb_core.c index 61da471b7aed..3c6043c1b8ac 100644 --- a/drivers/usb/musb/musb_core.c +++ b/drivers/usb/musb/musb_core.c @@ -1517,7 +1517,7 @@ irqreturn_t musb_interrupt(struct musb *musb) devctl = musb_readb(musb->mregs, MUSB_DEVCTL); dev_dbg(musb->controller, "** IRQ %s usb%04x tx%04x rx%04x\n", - (devctl & MUSB_DEVCTL_HM) ? "host" : "peripheral", + is_host_active(musb) ? "host" : "peripheral", musb->int_usb, musb->int_tx, musb->int_rx); /* the core can interrupt us for multiple reasons; docs have @@ -1531,7 +1531,7 @@ irqreturn_t musb_interrupt(struct musb *musb) /* handle endpoint 0 first */ if (musb->int_tx & 1) { - if (devctl & MUSB_DEVCTL_HM) + if (is_host_active(musb)) retval |= musb_h_ep0_irq(musb); else retval |= musb_g_ep0_irq(musb); @@ -1545,7 +1545,7 @@ irqreturn_t musb_interrupt(struct musb *musb) /* musb_ep_select(musb->mregs, ep_num); */ /* REVISIT just retval = ep->rx_irq(...) */ retval = IRQ_HANDLED; - if (devctl & MUSB_DEVCTL_HM) + if (is_host_active(musb)) musb_host_rx(musb, ep_num); else musb_g_rx(musb, ep_num); @@ -1563,7 +1563,7 @@ irqreturn_t musb_interrupt(struct musb *musb) /* musb_ep_select(musb->mregs, ep_num); */ /* REVISIT just retval |= ep->tx_irq(...) */ retval = IRQ_HANDLED; - if (devctl & MUSB_DEVCTL_HM) + if (is_host_active(musb)) musb_host_tx(musb, ep_num); else musb_g_tx(musb, ep_num); @@ -1585,15 +1585,13 @@ MODULE_PARM_DESC(use_dma, "enable/disable use of DMA"); void musb_dma_completion(struct musb *musb, u8 epnum, u8 transmit) { - u8 devctl = musb_readb(musb->mregs, MUSB_DEVCTL); - /* called with controller lock already held */ if (!epnum) { #ifndef CONFIG_USB_TUSB_OMAP_DMA if (!is_cppi_enabled()) { /* endpoint 0 */ - if (devctl & MUSB_DEVCTL_HM) + if (is_host_active(musb)) musb_h_ep0_irq(musb); else musb_g_ep0_irq(musb); @@ -1602,13 +1600,13 @@ void musb_dma_completion(struct musb *musb, u8 epnum, u8 transmit) } else { /* endpoints 1..15 */ if (transmit) { - if (devctl & MUSB_DEVCTL_HM) + if (is_host_active(musb)) musb_host_tx(musb, epnum); else musb_g_tx(musb, epnum); } else { /* receive */ - if (devctl & MUSB_DEVCTL_HM) + if (is_host_active(musb)) musb_host_rx(musb, epnum); else musb_g_rx(musb, epnum); -- 2.20.1