diff --git a/drivers/dma/dw_dmac.c b/drivers/dma/dw_dmac.c index decca1c3c83d..9b592b02b5f4 100644 --- a/drivers/dma/dw_dmac.c +++ b/drivers/dma/dw_dmac.c @@ -166,6 +166,38 @@ dwc_assign_cookie(struct dw_dma_chan *dwc, struct dw_desc *desc) return cookie; } +static void dwc_initialize(struct dw_dma_chan *dwc) +{ + struct dw_dma *dw = to_dw_dma(dwc->chan.device); + struct dw_dma_slave *dws = dwc->chan.private; + u32 cfghi = DWC_CFGH_FIFO_MODE; + u32 cfglo = DWC_CFGL_CH_PRIOR(dwc->priority); + + if (dwc->initialized == true) + return; + + if (dws) { + /* + * We need controller-specific data to set up slave + * transfers. + */ + BUG_ON(!dws->dma_dev || dws->dma_dev != dw->dma.dev); + + cfghi = dws->cfg_hi; + cfglo |= dws->cfg_lo & ~DWC_CFGL_CH_PRIOR_MASK; + } + + channel_writel(dwc, CFG_LO, cfglo); + channel_writel(dwc, CFG_HI, cfghi); + + /* Enable interrupts */ + channel_set_bit(dw, MASK.XFER, dwc->mask); + channel_set_bit(dw, MASK.BLOCK, dwc->mask); + channel_set_bit(dw, MASK.ERROR, dwc->mask); + + dwc->initialized = true; +} + /*----------------------------------------------------------------------*/ /* Called with dwc->lock held and bh disabled */ @@ -189,6 +221,8 @@ static void dwc_dostart(struct dw_dma_chan *dwc, struct dw_desc *first) return; } + dwc_initialize(dwc); + channel_writel(dwc, LLP, first->txd.phys); channel_writel(dwc, CTL_LO, DWC_CTLL_LLP_D_EN | DWC_CTLL_LLP_S_EN); @@ -959,10 +993,7 @@ static int dwc_alloc_chan_resources(struct dma_chan *chan) struct dw_dma_chan *dwc = to_dw_dma_chan(chan); struct dw_dma *dw = to_dw_dma(chan->device); struct dw_desc *desc; - struct dw_dma_slave *dws; int i; - u32 cfghi; - u32 cfglo; unsigned long flags; dev_vdbg(chan2dev(chan), "alloc_chan_resources\n"); @@ -975,26 +1006,6 @@ static int dwc_alloc_chan_resources(struct dma_chan *chan) dwc->completed = chan->cookie = 1; - cfghi = DWC_CFGH_FIFO_MODE; - cfglo = 0; - - dws = chan->private; - if (dws) { - /* - * We need controller-specific data to set up slave - * transfers. - */ - BUG_ON(!dws->dma_dev || dws->dma_dev != dw->dma.dev); - - cfghi = dws->cfg_hi; - cfglo = dws->cfg_lo & ~DWC_CFGL_CH_PRIOR_MASK; - } - - cfglo |= DWC_CFGL_CH_PRIOR(dwc->priority); - - channel_writel(dwc, CFG_LO, cfglo); - channel_writel(dwc, CFG_HI, cfghi); - /* * NOTE: some controllers may have additional features that we * need to initialize here, like "scatter-gather" (which @@ -1026,11 +1037,6 @@ static int dwc_alloc_chan_resources(struct dma_chan *chan) i = ++dwc->descs_allocated; } - /* Enable interrupts */ - channel_set_bit(dw, MASK.XFER, dwc->mask); - channel_set_bit(dw, MASK.BLOCK, dwc->mask); - channel_set_bit(dw, MASK.ERROR, dwc->mask); - spin_unlock_irqrestore(&dwc->lock, flags); dev_dbg(chan2dev(chan), @@ -1058,6 +1064,7 @@ static void dwc_free_chan_resources(struct dma_chan *chan) spin_lock_irqsave(&dwc->lock, flags); list_splice_init(&dwc->free_list, &list); dwc->descs_allocated = 0; + dwc->initialized = false; /* Disable interrupts */ channel_clear_bit(dw, MASK.XFER, dwc->mask); @@ -1335,6 +1342,8 @@ EXPORT_SYMBOL(dw_dma_cyclic_free); static void dw_dma_off(struct dw_dma *dw) { + int i; + dma_writel(dw, CFG, 0); channel_clear_bit(dw, MASK.XFER, dw->all_chan_mask); @@ -1345,6 +1354,9 @@ static void dw_dma_off(struct dw_dma *dw) while (dma_readl(dw, CFG) & DW_CFG_DMA_EN) cpu_relax(); + + for (i = 0; i < dw->dma.chancnt; i++) + dw->chan[i].initialized = false; } static int __init dw_probe(struct platform_device *pdev) @@ -1533,6 +1545,7 @@ static int dw_suspend_noirq(struct device *dev) dw_dma_off(platform_get_drvdata(pdev)); clk_disable(dw->clk); + return 0; } diff --git a/drivers/dma/dw_dmac_regs.h b/drivers/dma/dw_dmac_regs.h index c3419518d701..5eef6946a367 100644 --- a/drivers/dma/dw_dmac_regs.h +++ b/drivers/dma/dw_dmac_regs.h @@ -140,6 +140,7 @@ struct dw_dma_chan { u8 mask; u8 priority; bool paused; + bool initialized; spinlock_t lock;