On Saturday 07 March 2009, Sergei Shtylyov wrote: > 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.
Also, the semantics of mass storage stall are not the same as the USB ch9 semantics ... that's why the set_wedge() operation is now defined. Could you take another whack at this, and include set_wedge()? I'll give this an eyeballing anyway, on the grounds that at least some parts of this are probably right already ... just, the mass storage support can't be exactly correct. - Dave > > 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; > } > > -- > To unsubscribe from this list: send the line "unsubscribe linux-usb" in > the body of a message to [email protected] > More majordomo info at http://vger.kernel.org/majordomo-info.html > > _______________________________________________ Davinci-linux-open-source mailing list [email protected] http://linux.davincidsp.com/mailman/listinfo/davinci-linux-open-source
