Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1758630AbZLGAOA (ORCPT ); Sun, 6 Dec 2009 19:14:00 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1758440AbZLGAN4 (ORCPT ); Sun, 6 Dec 2009 19:13:56 -0500 Received: from kroah.org ([198.145.64.141]:34654 "EHLO coco.kroah.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1758460AbZLGANn (ORCPT ); Sun, 6 Dec 2009 19:13:43 -0500 X-Mailbox-Line: From gregkh@mini.kroah.org Sun Dec 6 16:06:56 2009 Message-Id: <20091207000656.289038717@mini.kroah.org> User-Agent: quilt/0.48-1 Date: Sun, 06 Dec 2009 16:01:03 -0800 From: Greg KH To: linux-kernel@vger.kernel.org, stable@kernel.org Cc: stable-review@kernel.org, torvalds@linux-foundation.org, akpm@linux-foundation.org, alan@lxorguk.ukuu.org.uk, Sergei Shtylyov Subject: [087/119] USB: musb_gadget: fix STALL handling References: <20091206235936.208334321@mini.kroah.org> Content-Disposition: inline; filename=usb-musb_gadget-fix-stall-handling.patch In-Reply-To: <20091207000938.GA24743@kroah.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 6953 Lines: 219 2.6.31-stable review patch. If anyone has any objections, please let us know. ------------------ From: Sergei Shtylyov commit cea83241b3a84499c4f9b12f8288f787e7aa6383 upstream. The driver incorrectly cancels the mass-storage device CSW request (which leads to device reset) due to giving back URB at the head of endpoint's queue after sending each STALL handshake; stop doing that and start checking for the queue being non-empty before stalling an endpoint and disallowing stall in such case in musb_gadget_set_halt() like the other gadget drivers do. Moreover, the driver starts Rx request despite of the endpoint being halted -- fix this by moving the SendStall bit check from musb_g_rx() to rxstate(). And we also sometimes get into rxstate() with DMA still active after clearing an endpoint's halt (not clear why), so bail out in this case, similarly to what txstate() does... While at it, also do the following changes : - in musb_gadget_set_halt(), remove pointless Tx FIFO flushing (the driver does not allow stalling with non-empty Tx FIFO anyway); - in rxstate(), stop pointlessly zeroing the 'csr' variable; - in musb_gadget_set_halt(), move the 'done' label to a more proper place; - in musb_g_rx(), eliminate the 'done' label completely... Signed-off-by: Sergei Shtylyov Signed-off-by: Greg Kroah-Hartman --- drivers/usb/musb/musb_gadget.c | 79 +++++++++++++++++------------------------ 1 file changed, 34 insertions(+), 45 deletions(-) --- a/drivers/usb/musb/musb_gadget.c +++ b/drivers/usb/musb/musb_gadget.c @@ -4,6 +4,7 @@ * Copyright 2005 Mentor Graphics Corporation * Copyright (C) 2005-2006 by Texas Instruments * Copyright (C) 2006-2007 Nokia Corporation + * Copyright (C) 2009 MontaVista Software, Inc. * * This program is free software; you can redistribute it and/or * modify it under the terms of the GNU General Public License @@ -436,14 +437,6 @@ void musb_g_tx(struct musb *musb, u8 epn csr |= MUSB_TXCSR_P_WZC_BITS; csr &= ~MUSB_TXCSR_P_SENTSTALL; musb_writew(epio, MUSB_TXCSR, csr); - if (dma_channel_status(dma) == MUSB_DMA_STATUS_BUSY) { - dma->status = MUSB_DMA_STATUS_CORE_ABORT; - musb->dma_controller->channel_abort(dma); - } - - if (request) - musb_g_giveback(musb_ep, request, -EPIPE); - break; } @@ -582,15 +575,25 @@ void musb_g_tx(struct musb *musb, u8 epn */ static void rxstate(struct musb *musb, struct musb_request *req) { - u16 csr = 0; const u8 epnum = req->epnum; struct usb_request *request = &req->request; struct musb_ep *musb_ep = &musb->endpoints[epnum].ep_out; void __iomem *epio = musb->endpoints[epnum].regs; unsigned fifo_count = 0; u16 len = musb_ep->packet_sz; + u16 csr = musb_readw(epio, MUSB_RXCSR); - csr = musb_readw(epio, MUSB_RXCSR); + /* We shouldn't get here while DMA is active, but we do... */ + if (dma_channel_status(musb_ep->dma) == MUSB_DMA_STATUS_BUSY) { + DBG(4, "DMA pending...\n"); + return; + } + + if (csr & MUSB_RXCSR_P_SENDSTALL) { + DBG(5, "%s stalling, RXCSR %04x\n", + musb_ep->end_point.name, csr); + return; + } if (is_cppi_enabled() && musb_ep->dma) { struct dma_controller *c = musb->dma_controller; @@ -761,19 +764,10 @@ void musb_g_rx(struct musb *musb, u8 epn csr, dma ? " (dma)" : "", request); if (csr & MUSB_RXCSR_P_SENTSTALL) { - if (dma_channel_status(dma) == MUSB_DMA_STATUS_BUSY) { - dma->status = MUSB_DMA_STATUS_CORE_ABORT; - (void) musb->dma_controller->channel_abort(dma); - request->actual += musb_ep->dma->actual_len; - } - csr |= MUSB_RXCSR_P_WZC_BITS; csr &= ~MUSB_RXCSR_P_SENTSTALL; musb_writew(epio, MUSB_RXCSR, csr); - - if (request) - musb_g_giveback(musb_ep, request, -EPIPE); - goto done; + return; } if (csr & MUSB_RXCSR_P_OVERRUN) { @@ -795,7 +789,7 @@ void musb_g_rx(struct musb *musb, u8 epn DBG((csr & MUSB_RXCSR_DMAENAB) ? 4 : 1, "%s busy, csr %04x\n", musb_ep->end_point.name, csr); - goto done; + return; } if (dma && (csr & MUSB_RXCSR_DMAENAB)) { @@ -826,22 +820,15 @@ void musb_g_rx(struct musb *musb, u8 epn if ((request->actual < request->length) && (musb_ep->dma->actual_len == musb_ep->packet_sz)) - goto done; + return; #endif musb_g_giveback(musb_ep, request, 0); request = next_request(musb_ep); if (!request) - goto done; - - /* don't start more i/o till the stall clears */ - musb_ep_select(mbase, epnum); - csr = musb_readw(epio, MUSB_RXCSR); - if (csr & MUSB_RXCSR_P_SENDSTALL) - goto done; + return; } - /* analyze request if the ep is hot */ if (request) rxstate(musb, to_musb_request(request)); @@ -849,8 +836,6 @@ void musb_g_rx(struct musb *musb, u8 epn DBG(3, "packet waiting for %s%s request\n", musb_ep->desc ? "" : "inactive ", musb_ep->end_point.name); - -done: return; } @@ -1244,7 +1229,7 @@ int musb_gadget_set_halt(struct usb_ep * void __iomem *mbase; unsigned long flags; u16 csr; - struct musb_request *request = NULL; + struct musb_request *request; int status = 0; if (!ep) @@ -1260,24 +1245,29 @@ int musb_gadget_set_halt(struct usb_ep * musb_ep_select(mbase, epnum); - /* cannot portably stall with non-empty FIFO */ request = to_musb_request(next_request(musb_ep)); - if (value && musb_ep->is_in) { - csr = musb_readw(epio, MUSB_TXCSR); - if (csr & MUSB_TXCSR_FIFONOTEMPTY) { - DBG(3, "%s fifo busy, cannot halt\n", ep->name); - spin_unlock_irqrestore(&musb->lock, flags); - return -EAGAIN; + if (value) { + if (request) { + DBG(3, "request in progress, cannot halt %s\n", + ep->name); + status = -EAGAIN; + goto done; + } + /* Cannot portably stall with non-empty FIFO */ + if (musb_ep->is_in) { + csr = musb_readw(epio, MUSB_TXCSR); + if (csr & MUSB_TXCSR_FIFONOTEMPTY) { + DBG(3, "FIFO busy, cannot halt %s\n", ep->name); + status = -EAGAIN; + goto done; + } } - } /* set/clear the stall and toggle bits */ DBG(2, "%s: %s stall\n", ep->name, value ? "set" : "clear"); if (musb_ep->is_in) { csr = musb_readw(epio, MUSB_TXCSR); - if (csr & MUSB_TXCSR_FIFONOTEMPTY) - csr |= MUSB_TXCSR_FLUSHFIFO; csr |= MUSB_TXCSR_P_WZC_BITS | MUSB_TXCSR_CLRDATATOG; if (value) @@ -1300,14 +1290,13 @@ int musb_gadget_set_halt(struct usb_ep * musb_writew(epio, MUSB_RXCSR, csr); } -done: - /* maybe start the first request in the queue */ if (!musb_ep->busy && !value && request) { DBG(3, "restarting the request\n"); musb_ep_restart(musb, request); } +done: spin_unlock_irqrestore(&musb->lock, flags); return status; } -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/