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 checking 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()'s 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... --- Resending with the correct patch summary... This patch is atop of the Linus' tree plus 3 more patches posted earlier that haven't made it into any tree yet: http://marc.info/?l=linux-usb&m=123502258502676 http://marc.info/?l=linux-usb&m=123558766411239 http://marc.info/?l=linux-usb&m=123516211401715 It's a replacement (inexact -- it doesn't try to address issue with halting gadget by host) for 3 patches posted by Swaminathan Subbramanian in December: http://marc.info/?l=linux-usb&m=122831218103530 http://marc.info/?l=linux-usb&m=122838184202655 http://marc.info/?l=linux-usb&m=122840747806532 drivers/usb/musb/musb_gadget.c | 79 +++++++++++++++++------------------------ 1 files changed, 34 insertions(+), 45 deletions(-) Index: linux-2.6/drivers/usb/musb/musb_gadget.c =================================================================== --- linux-2.6.orig/drivers/usb/musb/musb_gadget.c +++ linux-2.6/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. <[email protected]> * * This program is free software; you can redistribute it and/or * modify it under the terms of the GNU General Public License @@ -435,14 +436,6 @@ 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; } @@ -581,15 +574,25 @@ 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; @@ -760,19 +763,10 @@ 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) { @@ -794,7 +788,7 @@ 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)) { @@ -825,22 +819,15 @@ 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)); @@ -848,8 +835,6 @@ 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; } @@ -1243,7 +1228,7 @@ 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) @@ -1259,24 +1244,29 @@ 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) @@ -1299,14 +1289,13 @@ 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; } _______________________________________________ Davinci-linux-open-source mailing list [email protected] http://linux.davincidsp.com/mailman/listinfo/davinci-linux-open-source
