From: Dmitry Osipenko Date: Sat, 11 May 2013 16:30:53 +0000 (+0400) Subject: dma: tegra: avoid channel lock up after free X-Git-Tag: next-20130617~70^2~2^2~1 X-Git-Url: https://git.karo-electronics.de/?a=commitdiff_plain;h=e914746058444209faf0dfec14fb45d77a6db477;p=karo-tx-linux.git dma: tegra: avoid channel lock up after free Lock scenario: Channel 1 was allocated and prepared as slave_sg, used and freed. Now preparation of cyclic dma on channel 1 will fail with err "DMA configuration conflict" because tdc->isr_handler still setted to handle_once_dma_done. This happens because tegra_dma_abort_all() won't be called on channel freeing if pending list is empty and channel not busy. We need to clear isr_handler on channel freeing to avoid locking. Signed-off-by: Dmitry Osipenko Acked-by: Stephen Warren Acked-by: Laxman Dewangan Signed-off-by: Vinod Koul --- diff --git a/drivers/dma/tegra20-apb-dma.c b/drivers/dma/tegra20-apb-dma.c index 5953547a5f75..f137914d7b16 100644 --- a/drivers/dma/tegra20-apb-dma.c +++ b/drivers/dma/tegra20-apb-dma.c @@ -1191,6 +1191,7 @@ static void tegra_dma_free_chan_resources(struct dma_chan *dc) list_splice_init(&tdc->free_dma_desc, &dma_desc_list); INIT_LIST_HEAD(&tdc->cb_desc); tdc->config_init = false; + tdc->isr_handler = NULL; spin_unlock_irqrestore(&tdc->lock, flags); while (!list_empty(&dma_desc_list)) {