> -----Original Message----- > From: Jarkko Nikula [mailto:jhnikula@xxxxxxxxx] > Sent: Wednesday, September 30, 2009 11:10 AM > To: Shilimkar, Santosh > Cc: hari n; Pandita, Vikram; linux-omap@xxxxxxxxxxxxxxx > Subject: Re: [OMAP3] ALSA driver 'suspend/resume' handlers > > On Tue, 29 Sep 2009 21:28:45 +0530 > "Shilimkar, Santosh" <santosh.shilimkar@xxxxxx> wrote: > > > > Having said that, there is also bug in the DMA driver which doesn't > > > disable the channel in linking cases. Since we use always hardware > > > synchronized method, hardware will take care of draining the buffer so > no > > > loss of data. > > > > > > So option B should be ok and USB case also would work as mentioned > above. > > > > Which option finally we converged on this issue? Shall we fix in the DMA > driver or you want to do this in ALSA? > > > For me it looks that at least the omap_stop_dma should be fixed to stop > ongoing transfer always when it's called. As the name suggest :-) Agree !! Have a look at below patch and let me know if it's ok. >From 6042ce380c36907b0740e208f243f00ca370d09e Mon Sep 17 00:00:00 2001 From: Santosh Shilimkar <santosh.shilimkar@xxxxxx> Date: Wed, 30 Sep 2009 11:26:24 +0530 Subject: [PATCH] ARM: OMAP: SDMA: Stop channel in omap_stop_dma() API for linking as well. OMAP sDMA driver API omap_stop_dma() doesn't really stop the dma when used in linking scenario. This patch fixes the same. Signed-off-by: Santosh Shilimkar <santosh.shilimkar@xxxxxx> Signed-off-by: Venkatraman S <svenkatr@xxxxxx> CC: Hari n <hari.zoom@xxxxxxxxx> CC: Jarkko Nikula <jhnikula@xxxxxxxxx> --- arch/arm/plat-omap/dma.c | 9 +++++---- 1 files changed, 5 insertions(+), 4 deletions(-) diff --git a/arch/arm/plat-omap/dma.c b/arch/arm/plat-omap/dma.c index fd3154a..633c123 100644 --- a/arch/arm/plat-omap/dma.c +++ b/arch/arm/plat-omap/dma.c @@ -975,6 +975,11 @@ void omap_stop_dma(int lch) { u32 l; + /* Disable the DMA channel */ + l = dma_read(CCR(lch)); + l &= ~OMAP_DMA_CCR_EN; + dma_write(l, CCR(lch)); + if (!omap_dma_in_1510_mode() && dma_chan[lch].next_lch != -1) { int next_lch, cur_lch = lch; char dma_chan_link_map[OMAP_DMA4_LOGICAL_DMA_CH_COUNT]; @@ -1000,10 +1005,6 @@ void omap_stop_dma(int lch) if (cpu_class_is_omap1()) dma_write(0, CICR(lch)); - l = dma_read(CCR(lch)); - l &= ~OMAP_DMA_CCR_EN; - dma_write(l, CCR(lch)); - dma_chan[lch].flags &= ~OMAP_DMA_ACTIVE; } EXPORT_SYMBOL(omap_stop_dma); -- 1.5.4.7 -- To unsubscribe from this list: send the line "unsubscribe linux-omap" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
