| Message ID | 1455181722-32099-1-git-send-email-peter.ujfalusi@ti.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On 02/11/2016 10:08 AM, Peter Ujfalusi wrote: > We need the callback to support the dmaengine_terminate_sync(). > > Signed-off-by: Peter Ujfalusi <peter.ujfalusi@ti.com> Looks good, but I noticed a slight race condition in edma_completion_handler(). You need to fetch echan->desc while holding the vchan.lock. Otherwise this can race against terminate_all() and the callback might get scheduled even though terminate_all() completed and then there is a race where the synchronize() operation could be called before the callback gets scheduled, which means it doesn't do its intended job. Highly unlikely to happen, but theoretically possible. -- To unsubscribe from this list: send the line "unsubscribe linux-omap" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
On Thu, Feb 11, 2016 at 11:08:42AM +0200, Peter Ujfalusi wrote:
> We need the callback to support the dmaengine_terminate_sync().
Applied, thanks
diff --git a/drivers/dma/edma.c b/drivers/dma/edma.c index 2dac314a2d7a..290e1a721c5b 100644 --- a/drivers/dma/edma.c +++ b/drivers/dma/edma.c @@ -869,6 +869,13 @@ static int edma_terminate_all(struct dma_chan *chan) return 0; } +static void edma_synchronize(struct dma_chan *chan) +{ + struct edma_chan *echan = to_edma_chan(chan); + + vchan_synchronize(&echan->vchan); +} + static int edma_slave_config(struct dma_chan *chan, struct dma_slave_config *cfg) { @@ -1808,6 +1815,7 @@ static void edma_dma_init(struct edma_cc *ecc, bool legacy_mode) s_ddev->device_pause = edma_dma_pause; s_ddev->device_resume = edma_dma_resume; s_ddev->device_terminate_all = edma_terminate_all; + s_ddev->device_synchronize = edma_synchronize; s_ddev->src_addr_widths = EDMA_DMA_BUSWIDTHS; s_ddev->dst_addr_widths = EDMA_DMA_BUSWIDTHS; @@ -1833,6 +1841,7 @@ static void edma_dma_init(struct edma_cc *ecc, bool legacy_mode) m_ddev->device_pause = edma_dma_pause; m_ddev->device_resume = edma_dma_resume; m_ddev->device_terminate_all = edma_terminate_all; + m_ddev->device_synchronize = edma_synchronize; m_ddev->src_addr_widths = EDMA_DMA_BUSWIDTHS; m_ddev->dst_addr_widths = EDMA_DMA_BUSWIDTHS;
We need the callback to support the dmaengine_terminate_sync(). Signed-off-by: Peter Ujfalusi <peter.ujfalusi@ti.com> --- drivers/dma/edma.c | 9 +++++++++ 1 file changed, 9 insertions(+)