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@@ -769,3 +769,63 @@ int s3c2410_dma_request(enum dma_ch channel,
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return chan->number | DMACH_LOW_LEVEL;
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}
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+
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+EXPORT_SYMBOL(s3c2410_dma_request);
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+
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+/* s3c2410_dma_free
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+ *
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+ * release the given channel back to the system, will stop and flush
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+ * any outstanding transfers, and ensure the channel is ready for the
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+ * next claimant.
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+ *
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+ * Note, although a warning is currently printed if the freeing client
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+ * info is not the same as the registrant's client info, the free is still
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+ * allowed to go through.
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+*/
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+
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+int s3c2410_dma_free(enum dma_ch channel, struct s3c2410_dma_client *client)
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+{
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+ struct s3c2410_dma_chan *chan = s3c_dma_lookup_channel(channel);
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+ unsigned long flags;
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+
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+ if (chan == NULL)
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+ return -EINVAL;
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+
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+ local_irq_save(flags);
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+
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+ if (chan->client != client) {
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+ printk(KERN_WARNING "dma%d: possible free from different client (channel %p, passed %p)\n",
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+ channel, chan->client, client);
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+ }
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+
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+ /* sort out stopping and freeing the channel */
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+
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+ if (chan->state != S3C2410_DMA_IDLE) {
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+ pr_debug("%s: need to stop dma channel %p\n",
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+ __func__, chan);
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+
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+ /* possibly flush the channel */
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+ s3c2410_dma_ctrl(channel, S3C2410_DMAOP_STOP);
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+ }
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+
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+ chan->client = NULL;
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+ chan->in_use = 0;
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+
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+ if (chan->irq_claimed)
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+ free_irq(chan->irq, (void *)chan);
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+
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+ chan->irq_claimed = 0;
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+
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+ if (!(channel & DMACH_LOW_LEVEL))
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+ s3c_dma_chan_map[channel] = NULL;
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+
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+ local_irq_restore(flags);
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+
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+ return 0;
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+}
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+
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+EXPORT_SYMBOL(s3c2410_dma_free);
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+
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+static int s3c2410_dma_dostop(struct s3c2410_dma_chan *chan)
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+{
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+ unsigned long flags;
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