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Diffstat (limited to 'target/linux/brcm2708/patches-4.4/0406-dmaengine-bcm2835-Fix-polling-for-completion-of-DMA-.patch')
-rw-r--r--target/linux/brcm2708/patches-4.4/0406-dmaengine-bcm2835-Fix-polling-for-completion-of-DMA-.patch68
1 files changed, 0 insertions, 68 deletions
diff --git a/target/linux/brcm2708/patches-4.4/0406-dmaengine-bcm2835-Fix-polling-for-completion-of-DMA-.patch b/target/linux/brcm2708/patches-4.4/0406-dmaengine-bcm2835-Fix-polling-for-completion-of-DMA-.patch
deleted file mode 100644
index 77d5d86ddc..0000000000
--- a/target/linux/brcm2708/patches-4.4/0406-dmaengine-bcm2835-Fix-polling-for-completion-of-DMA-.patch
+++ /dev/null
@@ -1,68 +0,0 @@
-From 1f38f6d05f4d79a6d13dba29db962e434d4fbb57 Mon Sep 17 00:00:00 2001
-From: Eric Anholt <eric@anholt.net>
-Date: Fri, 3 Jun 2016 19:29:11 -0700
-Subject: [PATCH] dmaengine: bcm2835: Fix polling for completion of DMA with
- interrupts masked.
-
-The tx_status hook is supposed to be safe to call from interrupt
-context, but it wouldn't ever return completion for the last transfer,
-meaning you couldn't poll for DMA completion with interrupts masked.
-
-This fixes IRQ handling for bcm2835's DSI1, which requires using the
-DMA engine to write its registers due to a bug in the AXI bridge.
-
-Signed-off-by: Eric Anholt <eric@anholt.net>
----
- drivers/dma/bcm2835-dma.c | 24 +++++++++++++++++++-----
- 1 file changed, 19 insertions(+), 5 deletions(-)
-
---- a/drivers/dma/bcm2835-dma.c
-+++ b/drivers/dma/bcm2835-dma.c
-@@ -588,16 +588,16 @@ static enum dma_status bcm2835_dma_tx_st
- struct virt_dma_desc *vd;
- enum dma_status ret;
- unsigned long flags;
-+ u32 residue;
-
- ret = dma_cookie_status(chan, cookie, txstate);
-- if (ret == DMA_COMPLETE || !txstate)
-+ if (ret == DMA_COMPLETE)
- return ret;
-
- spin_lock_irqsave(&c->vc.lock, flags);
- vd = vchan_find_desc(&c->vc, cookie);
- if (vd) {
-- txstate->residue =
-- bcm2835_dma_desc_size(to_bcm2835_dma_desc(&vd->tx));
-+ residue = bcm2835_dma_desc_size(to_bcm2835_dma_desc(&vd->tx));
- } else if (c->desc && c->desc->vd.tx.cookie == cookie) {
- struct bcm2835_desc *d = c->desc;
- dma_addr_t pos;
-@@ -609,11 +609,25 @@ static enum dma_status bcm2835_dma_tx_st
- else
- pos = 0;
-
-- txstate->residue = bcm2835_dma_desc_size_pos(d, pos);
-+ residue = bcm2835_dma_desc_size_pos(d, pos);
-+
-+ /*
-+ * If our non-cyclic transfer is done, then report
-+ * complete and trigger the next tx now. This lets
-+ * the dmaengine API be used synchronously from an IRQ
-+ * handler.
-+ */
-+ if (!d->cyclic && residue == 0) {
-+ vchan_cookie_complete(&c->desc->vd);
-+ bcm2835_dma_start_desc(c);
-+ ret = dma_cookie_status(chan, cookie, txstate);
-+ }
- } else {
-- txstate->residue = 0;
-+ residue = 0;
- }
-
-+ dma_set_residue(txstate, residue);
-+
- spin_unlock_irqrestore(&c->vc.lock, flags);
-
- return ret;